Author: jgscott2008

Chronic Inflammation and Cardiovascular Disease

All of the following discussion is taken from an excellent review paper: The Role of Inflammation in Cardiovascular Disease. It is not easy reading, so I’m going translate it into language that’s simpler for non-physicians to understand.

The cells that line the arteries in the body, including the arteries in the heart are called the vascular endothelium. In normal people, the endothelium has anti-inflammatory and antithrombotic (anti-clot forming) properties. It controls which molecules can cross it and which cannot. The endothelium also controls the smooth muscle contraction and relaxation which dilates or constricts the arteries. This takes place through the balance between the release of substances which dilate the arteries, such as nitric oxide (NO), and substances that constrict the arteries such as endothelin.

Effects of chronic inflammation on endothelium

Chronic inflammation from any cause reduces nitric oxide and endothelin, resulting in damage to the junctions between the endothelial cells. This allows larger molecules, like cholesterol to cross into the endothelial cells. When chronic inflammation is present, LDL (bad cholesterol) metabolism is shifted from large- and medium-size LDL particles towards small and dense LDL particles. These particles cause more atherosclerosis than larger ones because they are not cleared as well by the liver LDL receptors. They thus tend to persist in the circulation. These small dense LDL particles accumulate underneath the endothelium. These particles induce a local inflammatory response. White blood cells called macrophages engulf the LDL particles and release inflammatory cytokines. Many of these macrophages die forming a necrotic core. This stimulates the the formation of a fibrous collagen cap in the wall of the arteries over the LDL particles and dead macrophages.

From systemic inflammation to focal atherosclerosis

Even though inflammation is systemic, atheromatous plaques are focal. They tend to occur where arteries branch or on side branches because these areas are exposed to disturbed blood flow.

Stable vs unstable plaques

The plaques with the fibrous collagen caps when initially formed are stable. If chronic inflammation stops, then they remain stable and do not cause narrowing of the coronary arteries. If chronic inflammation persists then more macrophages continue to release inflammatory cytokines. These inflammatory molecules start to thin some of the fibrous caps making them unstable and prone to rupture.

What happens when a plaque ruptures?

When a plaque ruptures it exposes the interior of the plaque to the bloodstream. This activates the blood clotting system and a clot forms that can obstruct the artery. If it completely obstructs the artery it causes a classic heart attack, also called a STEMI (ST elevation myocardial infarction). The ST refers to a part of an electrocardiogram called the ST segment. In a classic heart attack there is elevation of the ST segments on the electrocardiogram. The elevation makes the electrocardiogram look like firemen’s hats. Here is an example of an electrocardiogram with marked elevation of the ST segments.

If the clot does not completely obstruct the artery the ST segments do not show elevation, but some damage to the heart muscle still happens. The symptoms of this kind of heart attack are similar to a classic heart attack with chest pain radiating to the arm or neck. This kind of heart attack is called an NSTEMI (Non-ST Elevation MI. It is usually detected by measuring enzymes that are released by the injured heart muscle.

Plaques that partially obstruct arteries

Even plaques that are stable and not in danger of rupture can get large enough to partially obstruct arteries in the heart. When these plaques obstruct more than 50% of the diameter of the artery they can cause symptoms. When a person exercises the heart muscle needs more blood and the obstruction limits the blood flow. In this case a person may get chest pain with exercise (angina) that goes away when they sit down and rest.

Strokes

Chronic inflammation causes exactly the same kind of changes in the carotid arteries and other arteries in the brain. Rupture of a plaque in these vessels can cause a stroke. Sometimes platelets adhere to a ruptured plaque in an artery that causes a transient obstruction of the artery that is then washed away by the blood stream. That results in temporary stroke symptoms that resolve in 5-10 minutes. This is called a TIA (Transient Ischemic Attack). A TIA can be a warning signal of risk of a bigger stroke. People who have TIA’s should be immediately evaluated for risk of a bigger stroke.

Treatment of vascular inflammation

Statins are a class of medicine that we used to think work primarily by lowering LDL cholesterol. It was later found that statins have a powerful anti-inflammatory effect. This may well be the major reason that statins reduce the risk of heart attack and stroke.

Bottom Line

Chronic inflammation results in changes in the endothelium of arteries in the heart and brain. These changes allow LDL cholesterol to accumulate in the endothelium causing fibrous plaques. Continued inflammation causes these plaques to become unstable and prone to rupture. Ruptured plaques cause blood clots to form which can lead to heart attacks and strokes. Statins have a powerful anti-inflammatory effect which may be the main reason they reduce the risk of heart attacks and strokes.

Inflammation: Pathway to Chronic Diseases

Inflammation is activation of the immune system in response to threat or injury to the body. Acute inflammation mobilizes the immune system to repair an injury or fight an infection. Once healing takes place the immune system goes back to baseline. Chronic inflammation, however, involves long term activation of the immune system caused by some ongoing stress to the body. More and more, researchers are beginning to show that chronic inflammation is the common pathway to many diseases. There are multiple causes of chronic inflammation. In this post I will write about the causes of chronic inflammation. I will also do a series of posts about the many diseases that chronic inflammation causes. These posts will be based on the structure of an excellent book: Inflamed – Deep Medicine and the Anatomy of Injustice. It is not easy to read because it is disturbing but I highly recommend it. I will also write about a test to measure chronic inflammation. I will write about things you can do to decrease chronic inflammation if you have it and how to prevent it if you don’t. There are many causes of chronic inflammation that have to do with the structure of our society. These are things an individual cannot control. These societal causes will take ongoing efforts by all of us to change some of the toxic structures of society.

The Process of Inflammation

The inflammatory process starts with damage or threat of damage to the body. That can be an infection, a wound, or perceived threat of such. The immune system mobilizes white blood cells called macrophages to the injured area or site of infection. The cells of the immune system also release a cascade of messenger molecules called cytokines that amplify inflammation. These include interleukin 1ß, interleukin- 6 and tumor necrosis factor -α. The liver also releases a protein called c-reactive protein. When the threat is neutralized the immune system helps the body start to heal by releasing anti-inflammatory cytokines including interleukin (IL)-1 receptor antagonist, IL-4, IL-10, IL-11, and IL-13.

In chronic inflammation the pro-inflammatory cytokines continue to predominate and the c-reactive protein continues to be elevated.

Causes of Chronic Inflammation

Causes an individual can do something about

Low levels of physical activity.
Having a BMI at or above 30 , especially when excess weight is deep within your belly (visceral fat). The best way to measure belly fat is to use a tape measure to measure your waist at the widest point. Increased belly fat is greater than 35 inches for women or greater than 40 inches for men
An imbalance of healthy and unhealthy bacteria in your intestine (dysbiosis). Dysbiosis can be caused by antibiotics and by eating foods low in soluble fiber.
Regularly eating foods that cause inflammation, especially highly processed foods, or foods high in sugar or salt
Inadequate sleep
Using tobacco products.
Regularly drinking too much alcohol
Periodontal disease (gum infection) and tooth decay
Perceived stress

Societal Causes

Experience of racism (structural or personal)
Poverty
Homelessness
Worry about debt
Work stress
Exposure to air pollution
Exposure to chemicals (pesticides and herbicides for farm workers, glyphosphate (RoundUp) for everyone, microplastics in our bloodstreams for everyone. Every day, we are surrounded by thousands of synthetic chemicals. They are in our food, clothes, tools, furniture, toys, cosmetics and medicines. We know the health effects of only a few of these).

Diseases caused by chronic inflammation

Cardiovascular Disease (coronary artery disease, heart attacks, congestive heart failure)
Strokes
Type 2 diabetes
Cancer (multiple types)
Inflammatory bowel disease (crohns disease, ulcerative colitis)
Rheumatoid Arthritis
Lupus and similar autoimmune diseases
Asthma
COPD
Pulmonary fibrosis
Depression

Tests to measure chronic inflammation

All of the inflammatory cytokines can be measured but those are expensive tests. A simple inexpensive test that measures inflammation, both acute and chronic is high sensitivity CRP. It will also be high with an acute infection or injury, but will return to normal after the infection or injury have resolved. If it remains elevated when you are not sick or injured it is a sign of chronic inflammation. It may be worth asking your doctor to order this test if you have any of the individual or societal risk factors for chronic inflammation. A normal hs-CRP is less than 0.55 mg/dl in men and less than 1.0 mg/dl in women. If your hs-CRP is high in the absence of acute infection or injury, that can serve as motivation to make lifestyle changes to decrease your chronic inflammation and put you in a population that has less risk of developing any of the diseases associated with chronic inflammation.

Anti-inflammatory lifestyle

Exercise regularly. The CDC recommends 30 minutes of moderate exercise (walking briskly) for 30 minutes at least 5 days a week.
Eat mostly unprocessed or minimally processed foods and avoid sugary drinks or foods with added sugar or high fructose corn syrup. Also include foods with high soluble fiber such as beans, carrots, sweet potatoes, nuts, berries and most fruits (not fruit juice). Organic foods, while more expensive, have no residual pesticides or herbicides. If you eat meat buy grass fed beef, and pasture raised chicken and pork. Eat more plant-based foods than meat.
Avoid taking antibiotics as much as possible
Sleep. Average at least 8 hours a night
Floss your teeth daily, brush twice a day and see your dentist every 6 months
If you don’t smoke, don’t start and if you do smoke quit.
It is better not to drink alcohol at all, but if you do limit it to 1 drink a day or less.
Learn meditation or self hypnosis to manage stress. There are good books and videos, but an in person course is best if it is available.
Drink only filtered water and not bottled water in plastic bottles
Gas stoves cause significant indoor air pollution. If possible switch to an electric stove. Induction type burners actually heat more quickly than gas. If you have to use a gas stove, be sure to turn the ventilator fan on and open a window if possible.

Bottom Line

Chronic inflammation is the common pathway for many chronic diseases. There are many individual strategies that reduce or prevent chronic inflammation. Many of these strategies are not possible for people with socioeconomic problems. The stress black people experience from structural and individual racism, homelessness or inadequate housing, anxiety over debt, exposure to environmental synthetic chemicals, and exposure to air pollution are societal problems that we all have a responsibility to address.

My next post will deal with chronic inflammation and cardiovascular disease.

Private Equity and Healthcare – A Match Not Made in Heaven

A recent article in the Washington Post reported on a hospital system, Steward Healthcare, that was started by a private equity firm, Cerberus, in 2010. It was based in Dallas and owned 30 hospitals across the country. It recently filed for bankruptcy, leaving patients to suffer and some to even die.

This is only the tip of an iceberg. Private equity funds have increasingly purchased healthcare organizations. According to the Lown Institute At least 386 hospitals are now owned by private equity firms, comprising 30% of for-profit hospitals in the U.S. In this post I will discuss effects of private equity ownership of hospitals on the quality and cost of care.

Private equity firms are businesses that seek large investors by having a very large minimum investment, so investors usually include both wealthy individuals and large institutional investors like pension funds, insurance companies, endowments, and sovereign wealth funds. Typical large private equity firms are Cerberus, Bain Capital, Apollo Global Management, TPG, KKR and Blackstone. Private equity firms are different from venture capitalists, who provide a cash infusion to small startups and hope they blossom into the next Facebook. Nor are they stock traders making split-second decisions to buy or sell shares in public companies. Rather, private equity funds aim to take control of a business for a relatively short time, restructure it and resell the company at a profit. Investors in private equity firms expect to make a much larger profit than typically provided by the stock market.

Private equity firms claim they are good for healthcare systems because they provide needed capital for investment in better quality care. Let’s look at the data and see if this is true. Remember that the purpose of a private equity fund is to make a large return for its investors. Its purpose is not to improve healthcare delivery.

Cost

A recent review of 55 studies of cost and quality of care in hospitals and nursing homes owned by private equity firms in the British Medical Journal found that costs to patients and insurers were increased in those institutions owned by private equity firms compared to non-equity owned institutions.

Quality of Care

The review in BMJ also found that effects on quality of care in private equity owned institutions was mixed to harmful. A recent study reported in the Journal of the American Medical Association reported higher complication rates in private equity owned hospitals. Here is a quote from the key points in the JAMA article:

“Private equity acquisition was associated with a 25.4% increase in hospital-acquired conditions, which was driven by falls and central line–associated bloodstream infections. Medicare beneficiaries at private equity hospitals were modestly younger, less likely to have dual eligibility for Medicare and Medicaid, and transferred more to other acute care hospitals relative to controls.“

Financial Engineering

Private equity firms use some money from investors and borrow the rest to purchase hospital systems. That’s why they are known as leveraged buyouts. They then saddle the hospital systems with the debt. In other words, they have very little “skin in the game.” They do well whether the hospital does or not.

Short Term Goals

Private equity firms make most of their profits when they sell the hospital or hospital system, and they look to exit within 5-8 years. Thus they look for ways to cut costs quickly like reducing staff or selling the hospital real estate.

Moral Hazard

Private equity firms can make a big profit and pay big dividends to investors even if the hospital goes bankrupt or struggles to survive and is unable to provide the services they did before. See this report about how this happened to one hospital system: Shell game. This is different from most investments where the success of the investor depends on how well the target company does.

Financialization of Hospitals

Financialization is a pattern in which profits come primarily through financial channels rather than through trade and commodity production. In healthcare that means that profits come from buying and selling hospitals rather than from the provision of medical care. This has happened for non-profit hospitals as well as for profit hospitals. For non-profits financialization has occurred by purchasing smaller hospitals, creating large medical systems that dominate the market. The acceleration of the acquisition and selling of for-profit hospitals by private equity firms started in the mid 1990’s and continues to accelerate.

Nursing Homes

In 2022 private equity firms owned 5% of nursing homes. As the purchasing trend accelerates, that number is almost certainly higher now. Studies show that private equity ownership results in an 11% increase in mortality, a 6% decrease in mobility, an 8% increase in bedsores and a 10% increase in pain. (Owner Incentives and Performance in Healthcare: Private Equity Investment in Nursing Homes)

Bottom Line

The preponderance of evidence shows that Private equity ownership of healthcare institutions results in lower quality and higher cost healthcare. It is only the worst aspect of financialization of healthcare that has occurred in the US. There are things the US could to about this if the political will were there. Here is a list of solutions from the Lown Institute:

Joint Liability. Currently PE firms can put all of their debt on the balance sheet of the firm they acquire, letting them off the hook for this debt and making it harder for the acquired company to succeed. “Requiring private equity firms to share in the responsibility of the debt…would prevent them from making huge profits while they are saddling hospitals and nursing homes with debts that ultimately impact worker pay and cut off care to patients,” write Stewart and Baker.
Regulate mergers. Private equity acquisitions often go under the radar because the acquisitions are small enough to not be reported to authorities. But the U.S. Federal Trade Commission could be more aggressive in evaluating mergers and buyouts by PE, as they have done recently in Texas, where a PE firm has been buying up numerous anesthesia practices.
Transparency of PE ownership. It can be hard to know when hospitals are bought by a PE firm. The Department of Health and Human Services could require disclosure of PE ownership for hospitals as they have done for nursing homes.
Remove tax loopholes. The carried interest loophole allows PE management fees to be taxed at as capital gains, which is a lower rate than corporate income. Closing this loophole would remove a big incentive that makes PE buyouts so attractive for firms.

If it becomes less lucrative for private equity firms to purchase and sell healthcare institutions then they will concentrate their investments elsewhere. That would be good for all of us.

Medicare Disadvantage – One More Time

The Medicare enrollment period has started and ends December 7. TV and social media are filled with ads about Medicare Advantage plans, which I continue to call Medicare Disadvantage plans. At present more than 50% of Medicare beneficiaries are enrolled in one of these plans. Because of a government crackdown on these plans, many insurance companies no longer offer them, and if your plan has been canceled you have a one time opportunity to return to traditional Medicare with the ability to purchase a supplemental plan without underwriting (underwriting means the insurance company can consider your prior health conditions and can deny coverage or charge you a lot more). If you decide to switch back to traditional Medicare while your Medicare Advantage plan is still available, you will not be able to purchase a supplemental plan without underwriting. That can get very expensive! Medicare Advantage plans give you lots of extra benefits as long as you stay healthy. If you get sick you end up paying a lot more! I did a post some time ago about what I call Medicare Disadvantage plans. Nothing has changed since I wrote that post Here is a link to that post: MEDICARE DISADVANTAGE PLANS: LOOK FOR THE FINE PRINT. If you are considering changing your Medicare plan, it is worth reading again.

Antivaxxers – What Motivates Them?

The scientific evidence is clear that vaccines, starting with the smallpox vaccine developed by Edward Jenner in 1796 have saved millions of lives. Mild adverse reactions such as fever, sore arm and fatigue are relatively common. Serious adverse reaction to any and all vaccines in use today are extremely rare, on the order of one in a million. These serious reactions are almost always severe allergic reactions that occur immediately and can be treated successfully.

Despite the overwhelming evidence of the safety and efficacy of vaccines, there have always been people who were opposed to vaccines starting with the smallpox vaccine in the 1790’s. Recently, perhaps due to the influence of social media, there are an increasing number of people who think that vaccines are harmful and refuse them for themselves and their children. These beliefs tend to be strongly held and not very amenable to change even when they are presented with the scientific evidence.

In this post I’m going to write about the reasons antivaxxers give for refusing vaccines and explore some possible reasons that it is so hard to change these erroneous beliefs.

Concerns about Safety of Vaccines

Autism

In 1998 Andrew Wakefield and twelve other authors authored a paper that was published in the New England Journal of Medicine suggesting that the MMR vaccine was associated with autism. The paper was eventually found to be based on fraudulent data and it was retracted. In the aftermath of the Wakefield article several large well designed studies showed no evidence of a connection between MMR or any other vaccine with autism. Nonetheless many people opposed to vaccines continue to site the discredited Wakefield paper.

Pertussis Vaccine

In the 1950’s there were some reports of children developing seizures after pertussis immunizations. An extensive review of these cases found no evidence that pertussis vaccine was the cause of the seizures. Because of public concern, the pertussis vaccine was reformulated so that it did not contain dead pertussis bacteria. This is now called acellular pertussis vaccine so that the combined diphtheria tetanus and acellular pertussis vaccine is abbreviated DTaP.

Thimerosal

In the 1960’s some people became concerned that some of the components of vaccines were toxic. The biggest concern was about a preservative called thimerosal, which contained a small amount of mercury. The vast majority of studies showed no evidence of any association between thimerosal exposure in vaccines and any adverse neurologic outcomes, but a few studies showed a slight association. Since 2001, no vaccines contain thimerosal.

Aluminum

Many vaccines contain a small amount of aluminum which serves to as an adjuvant, which means it increases the effectiveness of the vaccine. In large doses aluminum can cause neurological problems and autoimmune diseases. Some people have been concerned about the safety of aluminum in vaccines. Some people think Aluminum in vaccines causes autism. Aluminum is present in food and water in much higher doses than that present in vaccines. It is poorly absorbed and what is absorbed is quickly excreted in the urine. An FDA analysis shows that the body burden of aluminum following injections of aluminum-containing vaccines never exceeds safe US regulatory thresholds based on orally ingested aluminum even for low birth-weight infants. As noted previously a possible link to autism has been disproved by several large well designed studies.

Formaldehyde

Some people have expressed concern that formaldehyde in vaccines is toxic for children. Formaldehyde has a long history of safe use in the manufacture of certain viral and bacterial vaccines. It is used to inactivate viruses so they don’t cause disease and to detoxify bacterial toxins, such as the toxin used to make diphtheria vaccine. Almost all the formaldehyde is removed in the manufacturing process, but tiny amounts can remain. The body actually makes more formaldehyde which it uses in DNA synthesis than the tiny amount that remains in vaccines.

Lack of Trust

Although all of these concerns about toxins in vaccines have been addressed or disproved, there are still some people who lack trust in the vaccine manufacturers, the medical system and the CDC whose Advisory Committee on Immunization Practices (ACIP) makes recommendations for vaccine administration. Because of this mistrust, no amount of evidence from these groups will convince these people that vaccines are safe.

Religious Objections to vaccines

Although no major religions are opposed to vaccines, certain religious groups refuse vaccination. One common religious objection is that certain vaccines are manufactured by growing virus in fetal fibroblast cells from an aborted fetus. These cells were originally obtained from two aborted fetuses in the 1960’s. The cells have been cultured since then, so it is not necessary to obtain any more cells from fetuses. The viruses are separated from the cells, so that vaccines contain no fetal tissue. The vaccines that are grown in fetal fibroblast cells are the live virus vaccines including measles, mumps, rubella, chicken pox, the Imovax vaccine for rabies and the Janssen vaccine for COVID-19.

Opposition to Mandates

Americans are overwhelmingly supportive of all vaccination mandates with support ranging from a high 90 percent of respondents for DTaP, polio, chickenpox, and MMR to a low of 68 percent for COVID-19. Support of the HPV vaccine is somewhat lower, but still more than 50%. A smaller number of people feel that they should not be forced to vaccinate themselves or their children through state mandates. Some of this group may be willing to receive vaccinations if they feel they have a choice.

Philosophical Objections

There is a group of people who see some benefit in having their children contract certain preventable diseases. Some parents believe that natural immunity is better for their children than is immunity acquired through vaccinations. Others express the belief that if their child contracts a preventable disease, it will be beneficial for the child in the long term, as it will help make the child’s immune system stronger as he grows into adulthood. Some parents believe that the diseases for which we vaccinate are not very prevalent so their children are at minimal risk of contracting these diseases. For this reason, they also believe that the possible negative side effects of vaccine administration outweigh the benefits of the vaccines. Many parents do not see the preventable diseases as serious or life-threatening and would prefer to not put extra chemicals into their children’s bodies. Other parents think if their children have healthy diets and lifestyles they are at a decreased risk of contracting preventable childhood diseases. They also are under the assumption that if they were to contract one of the diseases that it would be easily treatable. Although all of this sounds reasonable on the surface it is absolutely wrong. See the good reasons to administer vaccinations in one of the sections below.

Conspiracy Theorists

Some people have a worldview that it’s commonplace for groups of elites to conduct elaborate and sinister hoaxes on the public, and to do so in near-perfect secrecy. They think this is just how the world works, and to believe anything else is naïve. There is a very strong correlation’s between conspiracy thinking and vaccine resistance.

Beliefs about conspiracies are very difficult to change. Evidence presented against the conspiracy by health care professionals are seen as part of the conspiracy. Conspiracy beliefs about vaccines can include believing the pharmaceutical companies or the CDC are covering up adverse effects of vaccines including that they cause autism.

Desire for Additional Information

Some parents are concerned about what they have seen on social media about vaccines and just want more information from health professionals about the safety and reasons for vaccines. This type of vaccine hesitancy is the most amenable for change by providing honest and clear information about the safety of vaccines.

The Good Reasons to Give Recommended Vaccines

It is true that many (but not all) of the diseases preventable by vaccines were relatively mild in most children. Prior to vaccines, however, 30 per cent of children died before the age of 5 from infectious diseases that are treatable or preventable today. Parents today have never seen a child with diphtheria, whooping cough, or tetanus. These were diseases that killed children prior to the vaccines and they could recur if enough people refuse vaccines.

Polio

The polio virus attacks the nervous system in children. It was a feared disease in the late 19th and early 20th century. In an outbreak in the early 1950’s. Over 2000 people died and many children had permanent paralysis. Paralysis of the respiratory system led to many children being placed in external respirators called iron lungs. Epidemics tended to occur in the summer. Parents kept children away from public gatherings like swimming pools and movie theaters. On April 12, 1955 the Salk vaccine was introduced and mass immunizations began, often in schools. Cases dropped dramatically. Several years later the Sabin oral polio vaccine was introduced. It was so effective that polio was completely eradicated in the United States. Polio vaccine is therefore no longer recommended for children in the US. Pockets of polio virus infection remain in other parts of the world. The most recent cases were in Gaza during the Israeli invasion of Gaza. Emergency vaccination of children in Gaza were carried out and the disease was brought under control.

Measles

Although measles is a relatively mild disease for most children it can be very severe and cause death for some. Before the introduction of measles vaccine in 1963 and widespread vaccination, major epidemics occurred approximately every two to three years and caused an estimated 2.6 million deaths each year.

Mumps

Mumps prior to the mumps vaccine was very common and mild in most children. Complications of mumps include inflammation of the testes, ovaries and pancreas, hearing loss, meningitis, and encephalitis. These are more common in adults than in children. Mumps was one of the most common causes of aseptic meningitis and hearing loss in children in the United States prior to the introduction of the vaccine.

Rubella

Rubella (German measles) is a mild disease but if contracted by a pregnant mother can result in severe fetal deformities and sometimes still birth. The rubella vaccine prevents rubella infection.

Influenza

Influenza occurs in epidemics. One strain in 1918 caused a pandemic with millions of deaths. There are always deaths from influenza in unvaccinated people every year. Influenza vaccine is effective in preventing or reducing the severity of illness. The influenza virus develops new mutations easily, so the vaccine has to be changed every year. The flu season in the southern hemisphere occurs during our summer, so flu vaccines for the northern hemisphere are developed based on the strains found to be circulating in the southern hemisphere flu season. This process can cause some variation in the effectiveness of the flu vaccine from year to year, but it always offers some protection and reduces the severity of illness from influenza virus.

Haemophilus Influenza

Before the Haemophilus influenza vaccine, this bacteria was the leading cause of bacterial meningitis, joint infection and ear infection in children. This vaccine was introduced after I was already in practice. I treated one case of bacterial meningitis in a child and several joint infections caused by H-flu. After widespread vaccination, I never saw another case.

Varicella (Chicken Pox)

Varicella is a very infectious disease in childhood. There are a few people, especially young infants who have severe disease requiring hospitalization. In the 25 years before the varicella vaccine was available there were over 2000 deaths from varicella. Giving the vaccine at 12-15 months of age protects vulnerable infants, and older people with chronic disease.

Human Papilloma Virus

The human papilloma virus (HPV) , which is transmitted by sexual intercourse, causes cervical cancer in some infected women. The HPV vaccine, given to preadolescent girls and boys prevents 90 % of cervical cancer in women.

Respiratory Syncytial Virus (RSV)

Most children and adults with RSV have mild cold-like symptoms with cough. About 3 per cent of babies with RSV have severe disease and require hospitalization and sometimes have to be placed on a mechanical ventilator. Young infants are more at risk as well as older adults, especially those with chronic disease. There is a vaccine for both babies and adults that is very effective at preventing RSV.

Rotavirus

Rotavirus is a highly contagious virus that infects the lining of the intestines. Symptoms include: High fever, Severe and persistent vomiting, and Diarrhea. It can usually be treated at home, but can cause severe dehydration. Prior to the availability of the oral rotavirus vaccine rotavirus was a leading cause of severe diarrhea in infants and children. There were 70,000 hospitalizations a year for rotavirus and 20-60 deaths per year. The oral vaccine is very effective at preventing rotavirus infection.

Hepatitis b

Hepatitis b can be contacted through sexual intercourse or by contaminated needles. Unlike hepatitis C, there is no effective treatment for hepatitis b. Hepatitis b can cause cirrhosis of the liver as well as liver cancer. Initially the vaccine was given only to high risk people, but it turned out that we were really bad at identifying who was at risk. Hepatitis b vaccine is now given to all babies and it has essentially eliminated hepatitis b.

Pneumoccocus

Before the vaccine, every year pneumococcus caused about 700 cases of meningitis, 17,000 cases of bloodstream infections, 200 deaths and 5 million ear infections in children. The pneumococcus vaccine is very effective at preventing these infections.

Meningococcus

Meningococcus is a bacterium that can cause meningitis or blood stream infection (sepsis). When it occurs It can be treated with antibiotics if caught quickly enough but it progresses so rapidly that people are deathly ill by the time they make it to the doctor. There is now a vaccine to prevent meningococcus infection. It is recommended for all adolescents between ages 11 and 12.

Shingles

Shingles is a reactivation in adults of childhood infection with chicken pox. It is a painful blistering rash along the distribution of a nerve on one side of the body. It can occur on any part of the body. Some people have persistent pain long after the rash is gone. This is called post herpetic neuralgia. Two doses of the vaccine called Shingrix is 98% effective at protecting adults from developing shingles. It is recommended for all adults age 50 and over.

Bottom Line

People can be opposed to receiving vaccines for themselves or their children for many reasons. Some people who just want more information can often be convinced of the safety of vaccines and then agree to be vaccinated. Other reasons such as mistrust of medical and public health sources of information and conspiracy thinking are very resistant to change. Philosophical objections including the belief that getting childhood illnesses gives better immunity and the low risk of infection of vaccine preventable diseases obviates the need for vaccinations are also resistant to change. The diseases that current vaccines prevent, although often mild in most people all have caused hospitalizations and deaths in the period prior to vaccine availability. All current vaccines have been shown to be very safe and associated with only mild transient side effects. Serious reactions to vaccines are extremely rare (on the order of one in a million) and are almost all amenable to treatment.

Mosquito Borne Diseases: Risks, Prevention & Treatment

Diseases carried by mosquitos have been in the news recently. Dr. Fauci had West Nile virus, which is carried by mosquitos. Some parks in Massachusetts have started an evening curfew because of cases of Eastern Equine Encephalitis, another mosquito borne disease. Mosquito borne diseases are rare in the US, but worldwide, mosquitos are the deadliest animal in the world. Worldwide, mosquito borne diseases kill 2.7 million people a year, 90% of which occur in Africa. As climate change causes increased global warming we are likely to see an increase in mosquito borne diseases in the US. In this post I will catalog all the mosquito borne diseases, which species of mosquitos carry them, and what areas have the most risk. Only a few species of mosquitos transmit diseases, but that information is primarily useful for epidemiologists and public health specialists. When a mosquito bites you, you are not going to know what species it is!

West Nile Virus

West Nile Virus is the most common disease transmitted by mosquitos, primarily by mosquitos of the culex species. Mosquitos get infected from birds and birds can get infected from infected mosquitos, so the disease passes back and forth between birds and mosquitos. People who get infected with West Nile cannot transmit it back to mosquitos that bite them.

Symptoms

Most people infected with West Nile virus do not have any symptoms but about 1 in 5 people who are infected develop a fever, headache, weakness, muscle pain, or joint pain, gastrointestinal symptoms and a transient rash. The illness usually lasts a few days, but can last for weeks. About 1 out of 150 infected people develop serious illness that invades the brain and spinal cord. This is called neuroinvasive illness. Sometimes this is fatal and if a person survives it they are likely to have permanent disability.

Species of mosquitos that carry it

Culex especially culex tarsalis

Treatment

There is no treatment or vaccine, so avoiding mosquito bites is the only way to keep from getting it when it has been identified in your area. I will write about the ways to avoid mosquito bites near the end of this post.

Who is at risk?

Cases are primarily in the summer and fall. Cases of West Nile disease have been reported across the continental United States. The CDC keeps track of human cases and cases identified in dead birds. West Nile virus occurs in epidemics in some years with few cases in others. So far in 2024 in the US there have been 289 cases of people with non-neuroinvasive West Nile illness and 189 cases of the serious neuroinvasive disease. Since 80% of infected people have no symptoms, that means the number of people with non-neuroinvasive infection so far this year is likely 5 x 289 = 1445. That is still a tiny percentage of the entire US population. Here is a link to the CDC web page showing 2024 West Nile cases by state and by county: West Nile Current Year Data (20240. If you live in an area where West Nile virus has has been identified in birds or humans, then you are at some increased risk.

Eastern Equine Encephalitis

The virus is maintained in fresh water hardwood swamps by birds and a particular species of mosquito called Culiseta melanura. This mosquito almost exclusively bites birds, so is not a significant risk to humans. The problem comes when infected birds are bitten by other species of mosquitos that do bite humans. Those species can infect humans.

Symptoms

Fortunately this is a rare disease. Thirty per cent of people infected with this virus die. Those who survive often have serious neurological problems. Symptoms are fever, headache, vomiting, diarrhea, seizures, behavioral changes, and drowsiness.

Species that transmit the disease to humans

Aedes, Coquillettidia, and Culex

Treatment

There is no vaccine or treatment for Eastern Equine Encephalitis. Avoiding mosquito bites is the only prevention. More about how to avoid mosquito bites later in this post.

Who is at risk?

Most cases are in the Eastern US. There have been only 4 cases so far this year according to the CDC data, but there was a death from a case just in the last few days in New Hampshire. The states that have recorded cases so far this year are Vermont, Massachusetts, New Jersey, Wisconsin and now New Hampshire. People who live in the northeast may need to be especially careful this year.

Cache Valley Virus

This virus is named for the Cache Valley in Utah where it was first recorded. It is very rare. Less than 10 cases have ever been reported. It has been reported in Illinois, Michigan, Missouri, New York, North Carolina, and Wisconsin. It is a severe disease.

Symptoms

Symptoms include stiff neck, confusion, loss of coordination, difficulty speaking, or seizures.

Species that transmit the disease

The virus has been found in several species (Anopheles, Culiseta, Coquillettidia). The main species that transmits the disease is not known.

Treatment

There is no vaccine or treatment. Avoiding mosquito bites is the only prevention. More about how to avoid mosquito bites later in this post.

Who is at risk?

This disease is so rare that there is no particular region of the US that is at risk. Mosquitos carrying the Cache Valley virus have been found in many additional locations in North America and in parts of Central America.

Jamestown Canyon Virus

The virus is maintained by mosquitos biting infected animals, mostly deer. Mosquitos cannot transmit disease from biting infected humans, so humans are considered a “dead end” host.

Symptoms

This is another relatively rare disease, but more frequent than Cache Valley Virus. Most infected people do not have symptoms, but a few people get severe neuroinvasive disease. The CDC counts only the severe cases, so the number of cases substantially underestimate the number of people infected. There are about 23 severe cases reported a year, mostly in the spring through fall. Symptoms include fever, fatigue and headache. Some people have respiratory symptoms such as cough, sore throat or runny nose. Symptoms of severe disease can include stiff neck, confusion, loss of coordination, difficulty speaking, or seizures. Death is rare from this disease.

Species that transmit the disease

Aedes, Culex, Coquillettidia

Treatment

There is no vaccine or treatment. Avoiding mosquito bites is the only prevention.

Who is at risk

Jamestown virus is found through most of the US, but Minnesota and Wisconsin have reported more than half of the cases. Again, there is no vaccine or treatment. Prevention is again the best option.

LaCrosse Virus

La Crosse virus circulates in the environment between tree hole breeding mosquitoes and small mammals, such as chipmunks or squirrels.

Symptoms

Most infected people do not have symptoms, but the disease can be severe especially in children under 16 years of age. Initial symptoms can include fever (usually lasting 2-3 days), headache, nausea, vomiting, fatigue , and lethargy. Symptoms of severe disease include high fever, headache, neck stiffness, stupor, disorientation, coma, seizures, muscle weakness, vision loss, numbness, and paralysis. Most patients recover but death from LaCrosse virus happens rarely.

Species that transmit the disease

Eastern tree hole mosquito (Aedes triseriatus). The tree hole mosquito is found almost exclusively in wooded or shady areas, and usually does not fly more than 200 yards from the area where it developed.

Treatment

There is no vaccine or treatment Avoiding mosquito bites is the only prevention.

Who is at risk?

Most cases occur in the upper Midwestern, mid-Atlantic, and southeastern states. LaCrosse virus is a rare disease. So far in 2024 there have been 13 cases of LaCrosse disease reported from Tennessee, North Carolina and South Carolina.

St Louis Encephalitis

St Louis Encephalitis virus circulates in the environment between mosquitos and birds.

Symptoms

Most infected people do not have symptoms. Severe disease usually occurs in older or immunocompromised people. Symptoms are fever, headache, dizziness, nausea, and generalized weakness. People with severe disease can develop stiff neck, confusion, disorientation, dizziness, tremors, and unsteadiness. 5-20% of infected people die from this disease. The risk of dying increases with age.

Species that transmit the infection

Culex

Treatment

There is no vaccine or treatment. Avoiding mosquito bites is the only prevention.

Who is at risk

In recent years sporadic cases and outbreaks have occurred in the Southwest. This is a rare disease and there have been no cases reported in 2024. In some years there are outbreaks primarily in urban areas. Again there is no vaccine or treatment for St Louis Encephalitis.

Dengue

Unlike many of the diseases discussed previously, Dengue virus circulates between humans and mosquitos. Mosquitos who bite infected people then spread the virus by biting other people. People can get Dengue multiple times.

Symptoms

Most infected people have no symptoms but 1 in 4 have symptoms which include Fever and bone and muscle pain. The pain can be severe. Dengue is also known as “break bone fever.” About 1 in 10 people who get sick have severe Dengue. Severe Dengue can result in shock, internal bleeding, and death. People with Dengue who have any of the following symptoms should go immediately to a hospital emergency department: belly pain or tenderness; vomiting; bleeding from the nose or gums; vomiting blood or blood in the stool.

Species that transmit the infection

Aedes.aegypti and Aedes.albopictus

Treatment

There is a vaccine for Dengue but it is only recommended for children who have already had one episode of Dengue. It is not available in the US. The only treatment is hospitalization and supportive care for severe illness.

Who is at risk?

Most Dengue in the US is in travelers from endemic areas. Endemic areas include the Caribbean, Central America, South America, Southeast Asia and the Pacific Islands. Many of these are popular tourist destinations, so the biggest risk for US citizens is travel to one of these regions. There have been some local outbreaks of Dengue in the US in Florida, Hawaii, Texas, Arizona, and California.

Treatment

Once again, other than the vaccine for children who have already had Dengue, treatment is supportive hospital care for people with severe Dengue. Travelers to endemic Dengue areas should use mosquito bite preventive measures, discussed further later in this post.

Chikungunya

Chikungunya virus, like Dengue, circulates in mosquitos and humans. Mosquitos become infected by biting a person with chikungunya virus and then spread the virus by biting other humans.

Symptoms

The most common symptoms are fever and joint pain and can include headache, muscle pain, joint swelling, or rash. Most patients feel better within a week, but joint pain can be severe and disabling and might persist for months. Death from chikungunya virus is rare.

Species that transmit the disease

Aedes.Stegomyia, Aedes.aegypti and Aedes.albopictus

Treatment

There is a vaccine for chikungunya. Travelers traveling to endemic areas may want to consider vaccination. There is no specific treatment. Avoiding mosquito bites is the only prevention.

Who is at risk?

There have been no cases of chikungunya in the US and US territories since 2019. Travelers to endemic areas are at risk. Endemic areas include Africa, the Americas, Asia, Europe, and islands in the Indian and Pacific Oceans. Travelers should check with the CDC travel website to see if outbreaks are occurring at their destinations.

Zika Virus

Like Dengue and chikungunya, Zika circulates between mosquitos and humans. If a mosquito bites a person infected with Zika virus in the first week of infection, the mosquito carries Zika to the next person it bites. Zika can also be transmitted through sex and can be transmitted from a pregnant mother to her fetus. Zika can cause severe birth defects when a pregnant mother is infected.

Symptoms

Most infected people have no symptoms, and when symptoms occur they tend to be mild. They include fever, rash, headache, joint pain, conjunctivitis (red eyes) and muscle pain. Symptoms are rarely severe enough to need hospitalization. The biggest problem with Zika is the birth defects caused by infection of pregnant women.

Species that transmit the disease

Aedes. aegypti and Aedes. albopictus

Treatment

There is no vaccine or treatment for Zika virus.

Who is at risk?

There have been no local cases of Zika in the US or US territories since 2019. People most at risk are travelers to countries that have outbreaks. Outbreaks occur in Mexico and South America and in certain countries in Africa and India. Other countries including the US have the Aedes species that can transmit Zika. Travelers to these areas should check with the CDC about current Zika outbreaks.

Yellow Fever

Yellow fever virus is maintained in forests between mosquitos and monkeys. People who work in forests where monkeys live can contract the virus this way. Mosquitos biting infected people can also spread the virus when mosquitos bite other people. Epidemics in urban areas occur this way.

Symptoms

Most people infected with yellow fever virus will either have no symptoms or mild symptoms and completely recover. Symptoms can include sudden onset of fever, chills, severe headache, back pain, general body aches, nausea, vomiting, fatigue, and weakness. Most people who develop symptoms improve within one week. A few people will develop a more severe form of the disease. Severe symptoms include high fever, yellow skin or eyes (jaundice), bleeding, shock, and organ failure. Among those who develop severe disease, 30-60% die

Species that transmit the disease

Primarily Aedes Aegypti

Treatment

There is an effective vaccine for prevention of yellow fever. Travelers going to an endemic yellow fever region should receive the vaccine before they travel. There is no treatment once someone has yellow fever.

Who is at risk?

There is no local transmission of yellow fever in the US. Yellow fever in travelers only rarely occurs. Yellow fever is endemic in Africa and South America.

Malaria

Malaria is caused by a parasite that resides in the liver and then infects red blood cells. It is maintained by circulation between mosquitos and humans. Mosquitos get infected from biting humans with malaria and then can transmit the parasite by biting other humans.

Symptoms

Malaria symptoms range from very mild illness to severe disease and even death. Early symptoms can include: Fever and flu-like illness, Chills, Headache, muscle aches, and tiredness. Nausea, vomiting, and diarrhea may also occur. If not treated quickly, the infection can become severe. Severe symptoms can include kidney failure, seizures, mental confusion, coma and death.

Species that transmit the disease

Anopheles

Treatment

Malaria can be treated successfully with several different drugs depending on the type and resistance. There are drugs that travelers can take if they are traveling to an area where malaria is present that will prevent infection. The newest development is a malaria vaccine that can be given to children in endemic malaria regions.

Who is at risk?

There is virtually no local transmission of malaria in the US in modern times. In a typical year, the U.S. reports about 2,000 cases of malaria, almost all of which are in travelers who have been to an endemic region. Malaria occurs only in tropical regions and below 6,500 feet above sea level. Most cases of malaria occur in sub-Saharan Africa, but it also occurs in parts of Oceania (such as Papua New Guinea) and in parts of Central and South America and Southeast Asia. Worldwide, malaria has caused 608,000 deaths in the past year. Malaria is one of the world’s most severe public health problems, with nearly half of the world’s population at risk for infection.

How to prevent mosquito bites.

Indoors

Make sure all windows have screens and any holes in the screens are patched. Use air conditioning if you have it during the spring and summer when mosquitos are most active.

Outdoors

Mosquitos lay eggs in standing water. Remove or empty any receptacles outside that allow water to pool such as saucers under flower pots. Tightly cover any water storage containers. If you have a birdbath, use a battery or solar powered agitator. Mosquitos only lay eggs in still water.

Residential outdoor misting systems that use permethrin provide good mosquito control and are safe for humans, birds and animals. They are somewhat expensive, however.

Use an EPA-registered insect repellant with one of the following ingredients:

DEET (Has been shown to be non-toxic for humans and repels but does not kill insects)
Picaridin (known as KBR 3023 and icaridin outside the United States)
IR3535
Oil of lemon eucalyptus (OLE)—A plant-derived ingredient (must be applied more frequently than DEET)
Para-menthane-diol (PMD)
2-undecanone—A plant-derived ingredient

Wear loose long sleeved shirts and long pants when outside when mosquitos are active

Treat items such as boots, pants, socks, and tents with permethrin or buy permethrin-treated clothing and gear.

Bottom Line

Mosquitos transmit many diseases, but all of these are quite rare in the US. Global warming may well increase mosquito transmitted diseases in the US in the future. The vast majority of mosquito bites in the US are just a nuisance and do not transmit disease. In other parts of the world mosquito disease transmission is a major public health problem. Travelers to areas where mosquito borne diseases are prevalent should use mosquito bite prevention strategies, especially EPA-approved insect repellents. Travelers to areas endemic for yellow fever should be vaccinated prior to travel. Travelers to malaria prevalent regions should start preventive medicine 1 week before and continue 1 week after travel.

Update on Diagnosis and Treatment of Alzheimers Disease

There are some new developments in the diagnosis of Alzheimer’s disease. These developments mean more people may be eligible for the new treatments for Alzheimer’ disease. In this post I will write about the new blood tests for Alzheimer’s disease and also revisit the available treatments. This will be an update of my previous post New Treatment for Early Alzheimer’s Disease – What You Need to Know.

Blood tests for Alzheimer’s disease

The monoclonal antibody treatments for Alzheimer’s disease only work if patients have evidence of amyloid proteins in their brains. Prior to the new blood tests, the only way to tell if patients had the amyloid protein was either to measure it in spinal fluid (which means a spinal tap) or to see it on a PET scan (which is a very expensive type of scan). The FDA has approved a new blood test that has been shown to work as well as a spinal tap or PET scan. It measures a protein called ptau217. The test is called the ALZpath ultra-sensitive pTau217 test. Because it requires just a blood sample, that means a lot more people will get the test and if positive will be eligible for treatment with the new monoclonal antibody treatments. This is a somewhat mixed blessing as I will outline below.

Theories of the cause of Alzheimer’s disease

On November 3, 1906, a clinical psychiatrist and neuroanatomist, Alois Alzheimer, reported “A peculiar severe disease process of the cerebral cortex” to the 37th Meeting of South-West German Psychiatrists in Tubingen, Germany. He described a 50-year-old woman whom he had followed from her admission for paranoia, progressive sleep and memory disturbance, aggression, and confusion, until her death 5 years later. His report noted distinctive plaques and neurofibrillary tangles in the brain at autopsy. In 1909 he presented two more patients with a similar history and pathology in the brain after death. These were all relatively young patients, so the name Alzheimer’s disease originally was applied to patients who developed dementia in their 50’s and 60’s (it was also called “pre-senile dementia.”

In later years it was discovered that many people who developed dementia at any age, including advanced age had the same plaques and neurofibrillary tangles when their brains were examined after they died. It turned out that 90 % of people who had dementia had these plaques and neurofibrillary tangles in their brains found at autopsy..

The Toxic Protein Hypothesis

The composition of the plaques turned out to be a protein called amyloid protein and the neurofibrillary tangles were composed of another protein called tau. The theory was that accumulation of these proteins was toxic to brain cells and that this toxic effect caused dementia. Because dementia is associated with age, it was hypothesized that in predisposed individuals gradual accumulation of these proteins in brain cells over many years eventually results in dementia.

There is one problem with this hypothesis. Several studies have followed aging people over time and measured the presence or absence of dementia. People in all these studies have agreed to have their brains studied after they died. In all of these studies anywhere from 12% to 30% of people who never had dementia during their long lifetimes (many were in their 80’s or older when they died) had plaques and neurofibrillary tangles that met the criteria for Alzheimer’s disease. It appears that the accumulation of amyloid and tau proteins is associated with Alzheimer’s dementia, but not necessarily the main cause of it.

Treatments based on the toxic protein hypthesis

There are three monoclonal antibodies now approved by the FDA for the treatment of Alzheimer’s disease. They newest ones are lecanemab and donanemab. They both target the amyloid beta protein that accumulates in people with Alzheimer’s disease. They are both used in people with mild cognitive impairment and they do reduce the beta amyloid protein as shown by follow up spinal fluid testing and/or PET scanning. Unfortunately, they only have a modest effect on slowing progression from mild cognitive impairment to Alzheimer’s disease. The cognitive test used in the studies of both drugs is called the Clinical Dementia Rating–Sum of Boxes. The range of this test is 0-18. Only people with mild cognitive impairment were included in the trials. The treatment group in the lecanemab trial got lecanemab, which has to be given by iv infusion every two weeks for 18 months. The placebo group got a saline infusion every two weeks. In both the placebo group and the treatment group, the scores on the dementia test got worse by 18 months, but the dementia scores for the treatment group did not increase as much as the placebo group. The absolute difference in the scores was about 14%. This was a statistically significant difference in slowing the progression of mild cognitive impairment to Alzheimer’s disease, but it’s not a very big difference.

Side effects of monoclonal antibody treatment

Both approved monoclonal antibody treatments attack the amyloid beta protein and produce an inflammatory response in the brain. This resulted in brain edema and/or micro hemorrhages in 17% of the treatment group vs 9% of the placebo group. Also nearly a quarter of the treatment group had reactions to the infusion. Most of the people with brain hemorrhages or edema did not have symptoms but some had headache, visual disturbance and confusion.

Expense of monoclonal antibody treatment

Lecanemab, which goes by the trade name Leqimbi is priced by the manufacturer at $26,500 per year. The other approved monoclonal antibody, aducanumab is priced at $28,200 per year. The UK has not approved either of these drugs because they don’t feel the modest benefit justifies the cost. The UK also points out that we have no idea what the long term effects of either one of these drugs might be.

Other treatments for Alzheimer’s disease

The other major class of drugs that has been used for Alzheimer’s disease are the cholinesterase inhibitors. The theory behind using these drugs is that nerve cells that produce a neurotransmitter called acetyl choline are diminished in Alzheimer’s disease. The cholinesterase inhibitors have the effect of increasing levels of acetyl choline in the brain because they inhibit the enzymes that break it down. These drugs are donazepil (Aricept), rivastigmine (Excelon), memantine in combination with donazepil (Namzeric), galantamine (Razadyne) and tacrine (Cognex).

These medicines don’t work very well Fourteen out of 100 patients with mild to moderate Alzheimer’s disease have some improvement in thinking skills. Side effects, especially nausea and vomiting are common. None of these medicines has been shown to work any better than the others in the class.

Genetics

There is no specific Alzheimer gene. Almost 80 genetic sequences have been identified that either decrease or increase the risk of Alzheimer’s disease. If you have a first degree relative who has had or has Alzheimer’s disease, then your risk is increased somewhat. Each of these sequences has only a minimal effect by itself, so you would have to have a lot of them to substantially increase the risk of Alzheimer’s disease. It is estimated that genetics accounts for less than 5% of Alzheimer’s disease.

Integrated theory of cause of Alzheimer’s disease

In doing research for this post, I discovered a very interesting paper by Richard Armstrong that reviews current theories of the cause of Alzheimer’s disease and proposes a new integrated theory that accounts for everything we know about Alzheimer’s disease so far. Here is a link to that paper if you would like to read the whole thing: Review article: What causes alzheimer’s disease?. It is from a Polish neurological journal, but the article is in english.

On the basis of current evidence Dr Armstrong believes that the primary factor in Alzheimer’s disease is an age-dependent breakdown of anatomical systems and pathways within the brain and the consequent loss of synapses. The degree of this aging effect depends on the amount of lifetime stress (also called allostatic load). The brain is the ultimate recipient of stress through hormonal changes resulting from high blood pressure, diabetes, cardiovascular disease, and immunological problems. The result of all this is gradual disconnection of synapses, degeneration of nerve cells, and the expression of genes determining various reactive and breakdown products such as Aβ and tau. The brain has a protective mechanism that removes breakdown products, and this protective mechanism continues to function and prevents the accumulation of Aβ and tau. As a person enters old age and the effects of excessive body stress accumulate, then senile plaques and neurofibrillary tangles begin to form as the brain’s protective systems get overwhelmed. In this theory, accumulation of Aβ and tau are the result of loss of synapses and connections in the brain rather than the cause. By the time these proteins can be detected in the spinal fluid or blood, the process of brain degeneration is already well underway. It is no wonder that targeting these proteins with monoclonal antibodies only modestly slows but does not reverse the progression of mild cognitive deficit to full blown Alzheimer’s disease.

If Doctor Armstrong’s theory is correct, then we should see a markedly increased risk of developing Alzheimer’s Disease with aging in people with certain chronic conditions. Here are some numbers:

Metabolic Syndrome

Metabolic syndrome is defined by having at least three of the following five conditions:

Excess abdominal fat (Waist circumference greater than 40 inches for men or 35 inches for women)
High blood pressure (Systolic greater than 140 or diastolic greater than 90)
High blood sugar (fasting blood sugar greater than 100 mg/dl)
high blood triglycerides (fasting triglycerides greater than 150 mg/dl)
Low HDL cholesterol (less than 40 mg/dl)

People with metabolic syndrome have 11.5 times the risk of developing Alzheimer’s disease as they age as people without metabolic syndrome. About one in every three adults in the US has metabolic syndrome.

Type 2 diabetes

A recent review of the literature found that type 2 diabetes increases the risk of eventually developing Alzheimer’s disease by 56%.

Coronary artery disease

People with coronary artery disease, especially at a relatively young age have a 26% increased risk of eventually developing Alzheimer’s disease.

Sedentary Lifestyle

In a study from the UK the more hours a person spent sedentary, the higher the risk of all cause dementia. Since Alzheimer’s disease accounts for the vast majority of dementia, we can assume that the more hours per day you spend on the couch, the greater the risk of eventually developing Alzheimer’s disease.

Social Networks

Many longitudinal studies show that maintenance of supportive social networks (family, friends) decreases the risk of development of Alzheimer’s disease. Conversely loneliness increases the risk of developing Alzheimer’s disease

Heavy alcohol consumption

Light to moderate alcohol consumption (2 drinks a day for men and 1 drink a day for women actually decreases the risk of developing Alzheimer’s disease. Heavy alcohol consumption (4 drinks a day or greater for men and 3 drinks a day or greater for women) increases the risk of developing Alzheimer’s disease by 300%!

Bottom Line

The new blood tests help diagnose people with mild cognitive impairment who are at high risk of progressing to Alzheimer’s disease. This is only helpful if there are good treatments to prevent progression to Alzheimer’s disease. Unfortunately, the best current treatments modestly slow the progression from mild cognitive impairment to Alzheimer’s disease but do not reverse or prevent the progression. These monoclonal antibody treatments have significant side effects that include microhemorrhages and brain edema. At present there is no medical treatment to reverse or prevent Alzheimer’s disease.

Dr. Armstrong has proposed a theory that the non-hereditary form of Alzheimer’s disease results from loss of synaptic connections in the brain from chronic lifetime body stress and that the amyloid protein accumulations are the result rather than the cause of loss of synaptic connections in the brain. This theory is supported by the fact that people with lifestyle related chronic diseases (metabolic syndrome, diabetes, heart disease, sedentary lifestyle, lack of meaningful mental activity, loneliness, heavy alcohol intake) have a markedly increased risk of developing Alzheimer’s disease as they age.

The best treatment for Alzheimer’s disease is prevention. Risk of developing Alzheimer’s disease with age is decreased by maintaining normal body weight, eating mostly unprocessed foods, exercising regularly, staying mentally active, maintaining supportive social networks, and avoiding heavy alcohol intake.

What is Healthy Eating?

In my last post I wrote about energy balance and the complex control of appetite and metabolism. I also wrote about diets for weight loss and how well they work and how sustainable they are. In this post I’m going to write about what we can eat that is good for our individual health as well as for the health of the planet.

Traditional Cuisines

People across the world do not eat the same things. Nonetheless, all traditional cuisines (not including the ones that have been “westernized”) are associated with good health and low risk of cardiovascular disease and stroke. This even includes the traditional Inuit cuisine, which is very high in meat (seal and other marine mammals), fat and fish.

What all these traditional cuisines have in common is that they are high in unprocessed or minimally processed foods. Meat is not a large part of any of the traditional cuisines, with a few exceptions, but it is not absent in most traditional cuisines.

Healthy Plant-based Foods

There are no particular vegetables, fruits, nuts or berries that you have to have in your diet in order to have a healthy plant-based diet. The trick is to eat a variety of plant-based foods. If you want to have an entirely plant-based diet, that can be very healthy but no one plant protein includes all the essential amino acids. In order to get all the essential amino acids you must be sure to include legumes, lentils and nuts in your diet as well as leafy vegetables and potatoes.

Is a plant-based diet better for the environment than one that includes meat?

The answer to this question is complicated. Some people choose vegan diets because they don’t believe in killing animals for food. Growing vegetables, fruits and nuts results in killing lots of animals and insects however. Most vegetables, fruits and nuts are grown in monocultures. Monoculture attracts large numbers of animals and insects that eat those crops. Farmers use insecticides and rodent poison to kill insects, including beneficial insects, mice and rats. Farmers are allowed to shoot deer that are eating their crops. Even farmers who grow organic vegetables use things like BT and neem oil to kill insects. People who think no animals die when they eat a vegan diet are mistaken. Soybeans in particular are grown in large monocultures and the USDA has a hard time policing soy that is supposed to be organic, but is not.

The use of manufactured fertilizer is another problem. Synthetic fertilizers, especially the nitrogen component are made from natural gas (which is mostly methane). Phosphate and potassium have to be mined.

Many food crops are genetically modified for insect and herbicide resistance. Food and fiber plants that are resistant to glyphosphate (Roundup) have resulted in detectable glyphosphate levels in all animals including humans. Corn that has been genetically modified to include BT has been harmful to honey bees.

So the answer to whether a vegan diet is good for the planet depends on how those vegetables, fruits berries and nuts are grown. Growing your own or getting vegetables from known small farm sources can be very good for the environment. Truck farming in large monocultures is not so good for the planet.

Is eating meat healthy and is it bad for the planet?

The current way that most meat animals are raised is not only cruel to the animals, but bad for the environment. Most meat animals (at least in wealthy western countries) are raised in CAFO’s (Concentrated Animal Feeding Operations). There is an alternative way to raise meat animals that is not bad for the planet. I will write about that shortly, but first I want to show you some examples of CAFO’s. Most meat eaters buy meat in the grocery store, neatly packaged. Since most people do not live on farms anymore, we are separated from and do not witness the killing of the animals whose meat we eat. I’m about to show you some disturbing photographs of how animals are treated in CAFO’s. After that I will write about how it is possible to eat meat from animals who are treated well up until the day they are killed.

This is a typical photograph of how our meat chickens are raised. This is a broiler CAFO

This is caged CAFO egg production. These chicken live their whole lives in these cages

This is a CAFO beef cattle feed lot. These animals are fed grain to fatten them up before they are sent to the slaughterhouse.

This if a pig CAFO. The animals hardly have room to turn around.

If you buy meat in a grocery store and you don’t know the source of the meat, it likely comes from a CAFO like these. Another problem with animal feeding operations like these is that they are fed grain that could be used for human consumption. It takes 6 pounds of grain for every pound of meat for cattle. Chickens require a little less and pigs a little more.

Farmed fish are raised in CAFO’s also. Here are two images of salmon raised in pens. Many of them fail to thrive and die. The dead fish that have been autopsied show very high levels of stress hormones.

Other fish that are farmed in CAFO’s include tilapia, catfish and shrimp.

How to eat meat and fish ethically without harming the planet

Most of the information below comes from a book I recently read by an Australian farmer, Matthew Evans. It is called On Eating Meat – The truth about its production and the ethics of eating it. It is worth reading. The link is to Thrift Books, but you can also get it from Amazon.

The first thing we can do is to simply eat less meat. The US and Australia are the biggest meat eaters in the world, and every country that can afford it is also increasing the amount of meat they eat. This is simply not sustainable. Cattle from feed lots and chickens from CAFO’s add carbon to the atmosphere and make global warming worse. We need to follow journalist Michael Pollan’s succinct advice about diet: “Eat food (food is anything your grandmother would have recognized as food), mostly plants, not too much.”

Ungulates

Ungulates (cattle, sheep and goats) eat grass, which we can’t eat or digest, and turn it into meat, which we can eat. Although ungulates do burp some methane, they also store carbon from grass in their muscles. Eating grass fed beef (or lamb or goat) does not add new carbon to the atmosphere, especially if meat only makes up a small part of our diet. Grass fed beef and lamb can usually be found at farmer’s markets. Specialty grocery stores are beginning to carry grass fed beef and lamb, and it can also sometimes be found at health food stores.

Chickens

Pasture raised chickens eat plants, worms and insects for most of their diet. They are often supplemented with some organic feed. Again they are part of the carbon cycle and do not add new carbon to the atmosphere. Many of the stores that sell grass fed beef also sell pasture raised chickens. Beware of terms like “free range” and “natural”. Chickens can be called free range if the door to the chicken house is open for part of the day. Free range says nothing about the density of chickens in the chicken house. Once they are raised in high density they don’t go outside even though they technically can. Organic chicken is better than nothing because no antibiotics can be used and they have no added chemicals. Organic chickens can be raised at the same density as CAFO’s however.

Eggs

Cage free eggs means chickens are free to roam inside a building, but it does not mean they get to go outside. The density of the chickens can still be unacceptably high. Cage free is certainly better than CAFO caged egg production, but is still not ideal. Pasture raised egg production is best, but this is not a term that is regulated by the FDA. If the egg carton says pasture raised, look for a stamp that says “Certified Humane” and/or “Animal Welfare Approved.” These are third party organizations that certify that eggs come from pasture raised chickens.

Pigs

Pigs are not ungulates, so they do not eat grass, but they do eat plants, insects and nuts. This diet can be supplemented with silage and grain, but pigs will also eat table scraps, so like grass fed beef and lamb, pigs can turn something we normally throw away into nutritious meat. Pasture raised pigs get to behave like pigs, which includes rooting and digging as well as running. Their meat is therefore less fat and more nutritious. Pasture raised pork is a little harder to find than grass fed beef and pasture raised chickens. Farmers markets are probably the best source.

Cornucopia

There is an excellent non-profit organization called Cornucopia. They rank sources of both animals and plants for ethical standards. They have scorecards for beef chicken, eggs, dairy, yogurt, cereal and others. They also include where to obtain each type of food. Here is a link to their website: Cornucopia.org.

Fish

There is no question that eating fish is good for your health. although children and pregnant women need to be careful because some ocean fish has a substantial amount of mercury. The fish with the highest levels of mercury are shark, swordfish, fresh tuna marlin, king mackerel, tilefish from the Gulf of Mexico, and northern pike. These species should probably be avoided by children and pregnant women.

Some type of fish are farmed sustainably and others are not. Wild caught fish is usually better, but not always. The Monterey Bay Aquarium has a rating service that is based on science and what is known about fish stocks Their service is called Seafood Watch. The service has the following ratings:

BEST CHOICEBuy first. Green rated seafood is well managed and caught or farmed in an environmentally responsible manner. It poses a low environmental risk.
CERTIFIEDBuy the certified products listed on our website.
GOOD ALTERNATIVEBuy if a Best Choice option is not available. This seafood poses a moderate environmental risk.
AVOIDTake a pass on this red rated seafood for now because it poses a high risk to the environment. They’re overfished, lack strong management, or are caught or farmed in ways that harm other marine life or the environment

They also have a super green list of seafood no-brainers. The database includes almost all edible fish with ratings for each one. Here is a link to their website: Monterey Bay Aquarium Seafood Watch.

Bottom Line

Traditional cuisines, which include many types of foods and that have not been westernized are all healthy and decrease your risk of heart disease compared to the standard American Diet.

Whether you are a vegan, vegetarian or include meat in your diet, the sources of your food have the most to do with how healthy what you eat is for you and for the planet.

The current level of meat that western countries eat is not sustainable for the planet. Meat should not be the main part of your diet. If you are a meat eater you should eat grass fed beef and lamb, pastured chicken and eggs, pastured pork and sustainable fish – wild caught or farmed responsibly.

CAFO’s are cruel to animals and harmful to the environment. We should not include meat or fish from them in our food budgets. Meat from pasture raised animals costs substantially more than meat from CAFO’s. Since we should be eating less meat anyway the extra cost should be sustainable for most people.

Diets – Can They Result in Sustainable Weight Loss?

We are inundated from social media and other sources about diets and how well they work. In this post I’m going to describe the current most popular diets and how safe and effective they are at producing weight loss. I’m also going to write about the physiology of appetite, what controls appetite, and the mechanisms involved in weight regain after dieting. I will also discuss the ways people have discovered to maintain their weight loss. I am not going to discuss medicines for weight loss or bariatric surgery in this post. Those are subjects for another day. I did do a previous post on GLP1 agonists for weight loss. If you are interested you can link to that post here.

Energy Balance

Neither humans nor any other animal can survive without food. Our bodies convert food into the energy we need to keep our bodies intact and to be able to move about. The measure of the available energy in food is calories. A calorie is the amount of heat energy required to raise 1 gram of water by 1 degree centigrade. This is a very small amount of energy, so the unit we usually use is 1000 calories or kilocalories. When you see the number of calories on a food label, it is always means kilocalories even though it says “calories” on the label.

If on average we eat more calories than we use, our bodies store the extra energy as fat and we gain weight. If on average we use more energy than we get from our food, our bodies use the stored energy from fat and we lose weight. If on average we eat as many calories as we use, our weight is stable. We are in energy balance. We can also gain weight by increasing our muscle mass, but in this post I’m going to write about weight gain and loss as changes in body fat. This is an immutable law. Diet claims that calories don’t matter for weight loss are simply wrong. Calories in versus calories out sounds simple, but energy balance in our bodies is not simple at all.

Our intake of calories is controlled by our appetite and the control of appetite involves multiple hormones and neurotransmitters at multiple places in the brain and in the body. Control of appetite is very complex. I will write more about this later in this post.

Energy we use is of two types. A certain amount of energy is needed just to keep our bodies functioning. This is called the basal metabolic rate. It is also called resting energy expenditure (REE). It varies with weight. The average REE is 1 kilocalorie per hour per Kg (2.2 pounds) of body weight. That means that for a person who weighs 70 Kg (154 pounds) the REE would be 1680 kilocalories per 24 hours, just sitting on the couch. To calculate your own REE, divide your body weight in pounds by 2.2 and multiply that by 24. That will give you the number of calories you use in 24 hours just sitting on the couch during the day and sleeping at night. In general it is going to be in the neighborhood of 1500 to 2000 kilocalories per day.

The other type of energy we use is the energy required to move our bodies. These are called active calories. Active calories also based on body weight. For a 154 pound person, walking briskly burns 280 calories per hour. More vigorous activity burns more calories. Here is an extensive table from the Department of Health Services of Wisconsin that shows kilocalories burned for various activities at different body weights: CALORIES BURNED PER HOUR.

So what would it take for you to be in energy balance if you weigh 70 Kg (154 pounds) and do brisk walking for 30 minutes 5 days a week? Brisk walking uses 280 kilocalories per hour, so 140 kilocalories for each exercise session. That would be 700 kilocalories per week or an average of 100 kilocalories per day. Regular household activities burn about the same amount per hour as walking, so if you do household chores for 4 hours per day including weekends, that would be another 1,120 kilocalories per day. Your REE is 1680 kilocalories per day. You would be burning on average 100 active kilocalories per day for your walking and another 1,120 kilocalories a day for household chores for a total of 2900 kilocalories per day. That number will be a little higher if you weigh more that 154 pounds and a little less if you weigh less than 154 pounds. To be in energy balance you would need to eat no more than 2900 kilocalories per day. If you exercise more, you can eat more and stay in energy balance, but you would need to add a lot more exercise.

Fortunately, you don’t have to do all these calculations. In a normal weight person your body stays in energy balance automatically. Obviously, people who are overweight or obese either are not now, or at some point have not been in energy balance. It doesn’t take being out of energy balance much per day to cause significant weight gain. Lets suppose you take in 100 more calories per day than you use. It takes about 3500 extra kilocalories to gain a pound of fat. That would equal weight gain of fat at a rate of a pound every 35 days, or 10 pounds per year.

Being overweight or obese has serious health consequences that escalate with the degree of obesity. In order for overweight or obese people to avoid these consequences, they need to make a conscious effort to lose weight. That is where diets come in. Exercise is important too, but more for maintaining weight loss than losing weight. Of course exercise is good for you whether you lose weight or not.

Diets

I will write about the most extreme diets first, and then discuss the more moderate ones.

Keto (ketogenic) Diet

The brain is the second most active organ in the body after the liver. The brain normally uses glucose for energy but when glucose is not available and all the glycogen in the liver (which can be converted to glucose) is used up, the body starts to break down fat into something called ketones. The brain can use ketones for energy although it cannot use fat directly. The purpose of the ketogenic diet is to switch the whole body to the use of ketones for energy instead of glucose. This is accomplished by a high fat, very low carbohydrate and low protein diet. Protein has to be low because it can be broken down in the liver to form glucose. Carbohydrate is reduced to less than 50 grams per day which is less than the amount in a medium bagel. Protein is restricted to less than 1 gram per pound of body weight per day.

The ketogenic diet works because it decreases appetite, so despite eating calorie dense fat, total calories consumed are markedly decreased. It does lead to significant and fairly rapid weight loss. It is, however a markedly nutrient deficient diet. People who are on this diet must take supplemental multivitamins and minerals. Doing so keeps people from getting gross vitamin deficiency, but there is also a loss of micronutrients found in complex carbohydrates and it is unclear what the effects of this deficiency are. The ketogenic diet is very low in fiber, which alters the gut microbiome adversely. It decreases triglycerides and increases HDL, which are good, but it also increases LDL, which is bad. On the other hand, it decreases hypertension and has an anti-inflammatory effect. It is not clear whether the positive effects are outweighed by the LDL increase effects. So far, there is no evidence that ketogenic diets increase the risk of heart disease.

The main drawback of the ketogenic diet besides the nutritional deficiencies is that it is virtually impossible to stick to for more than a few weeks or months. Ketogenic diets do reduce insulin secretion since there is much less glucose for insulin to carry into the cells. The ketogenic diet may be useful in type 2 diabetics to reduce insulin resistance and decrease weight, particularly for diabetics in poor control. It is not a diet that can be maintained long term.

Very Low Calorie Diets

These diets restrict calories to 800 calories per day or less using proprietary liquid formulas that contain electrolytes and high protein to prevent muscle loss. VLCD diets lead to rapid and significant weight loss and are used primarily for people with severe obesity or medical complications of obesity. Such a diet should not be used without supervision of a physician. Again, like the ketogenic diet, VLCD diets should not be maintained long term.

Intermittent Fasting

Intermittent fasting is going without food for some period. Non-caloric drinks such as water or coffee are encouraged during fasting times. The simplest is restricted time eating. This involves skipping one or two meals per day and only eating during a restricted time. Whole day fasts can be once or twice a week or even every other day. One might think that a person would eat twice as many calories on a non-fasting day and so would not experience weight loss. This rarely happens. Intermittent fasting does reduce average calorie intake, and so people on any of the intermittent fasting regimens lose weight. People who start an intermittent fasting diet get very hungry at first on fasting days, but this hunger tends to decrease over time. It takes discipline to maintain intermittent fasting over a long period, but people who have the discipline to stick to the intermittent fasting regimen can stay on it long term. If the food they eat on non-fasting days is healthy (more on this later) then this can be a successful long term eating plan to maintain energy balance at a lower weight.

Paleo Diet

This is supposedly the type of diet that humans ate in the paleolithic period prior to agriculture when all humans were hunter gatherers. Of course people on the paleo diet do not become hunter gatherers. According to the Mayo Clinic a modern paleo diet includes fruits, vegetables, lean meats -especially game meats, fish, eggs, nuts and seeds. These are foods that in the past people could get by hunting and gathering. It doesn’t include foods that became more common when small-scale farming began about 10,000 years ago. These foods include grains, legumes and dairy products.

People on a version of the paleo diet do lose weight for exactly the same reason as weight loss on other diets. The average calorie intake on the paleo diet is substantially less than the standard American diet. It is not clear that excluding grains, legumes and dairy products is a good thing. Whole grains, legumes and dairy products supply high quality nutrients that may be missing in the paleo diet. The paleo diet is also more expensive and may be out of reach for lower income people. There are no long term studies of the health effects of the paleo diet.

Whole30 Diet

This is similar to the paleo diet but is recommended for 30 days. Foods to avoid are alcohol, sugar, dairy products and legumes and grains. There is a list of foods you can eat and all of these are unprocessed foods. The idea is that you reset your metabolism, and then you gradually add back the avoided foods and see how they make you feel. There is no evidence about the claimed long term good health effects of the Whole30 Diet. Like other diets that lead to fewer calories consumed, people do lose weight on this diet.

Plant based Diet

A plant based diet is exactly what it says. It is derived entirely from plants and eliminates all animal products including dairy products and eggs. The sources of protein are legumes, nuts, seeds, soy and lentils. Sources of fat are nuts, avocados, olive oil and vegetable oils. Plant based diets tend to focus on unprocessed foods. Unlike the other diets mentioned in this post, there is a lot of evidence that plant-based diets decrease the risk of developing diabetes (and also treat type 2 diabetes), decrease the risk of high blood pressure, heart disease and autoimmune diseases. Plant based diets have an anti-inflammatory effect, which probably is responsible for many of the benefits of plant based diets.

Unprocessed plant based food is more expensive than ultra processed foods and requires substantially more preparation time. People who live in poor neighborhoods often live in a “food desert” and unprocessed plant foods may not be available or be too expensive to buy. People who have low end jobs often have neither the time nor the equipment for food preparation. Although plant based diets have multiple health benefits, they are out of reach for a substantial part of the US population.

GOLO Diet

The GOLO diet is a proprietary diet plan you have to pay for. It is essentially a Mediterranean type diet that includes a supplement. The supplement has a lot of minerals and vitamins and there is no evidence that any supplement helps with weight loss. It is currently heavily advertised on television and social media. The research cited in all of these ads is research funded by the GOLO company. I will write about the benefits of the Mediterranean type diet next, but GOLO uses a standard dietary plan and a worthless supplement to make money. Don’t waste your money on this diet.

Mediterranean Diet

The original Mediterranean diet was the traditional diet of Crete, Greece and southern Italy in the 1960’s. Italians and Greeks no longer necessarily eat like this, but their original diet had lots of whole grains, vegetables and fish and used lots of olive oil. This type of diet has been studied more than any other and has very similar benefits to the plant-based diet. It reduces the risk of high blood pressure, diabetes, heart disease and autoimmune disorders. Here is the Mediterranean diet food pyramid from Wikipedia. It was developed by Oldways Trust, Harvard and the World Health Organization.

The things at the base of the pyramid are the things you eat the most and the things at the top of the pyramid you eat the least. Notice that red meat and butter are at the top of the pyramid. You don’t eliminate any class of food entirely in this diet, you just don’t eat the things at the top very often. Once again the diet includes mostly unprocessed foods and requires considerable food preparation.

The Standard American Diet (Also called the Western pattern diet)

Here is a description of the Standard American Diet from Wikipedia: The Western pattern diet is a modern dietary pattern that is generally characterized by high intakes of pre-packaged foods, refined grains, red meat, processed meat, high-sugar drinks, candy and sweets, fried foods, industrially produced animal products, butter and other high-fat dairy products, eggs, potatoes, corn (and high-fructose corn syrup), and low intakes of fruits, vegetables, whole grains, pasture-raised animal products, fish, nuts, and seeds.

It is no wonder that we have an epidemic of obesity! The standard American diet is almost the exact opposite of the Mediterranean diet and plant-based diets. It is very high calorie and high in ultra-processed foods. That is why all of the diets I described above cause weight loss. Almost anything is better than the standard American diet!

Weight Regain After Weight Loss

With any diet (other than the very low calorie diets) weight loss stabilizes after a while and then there is very frequently some weight regain. Why does this happen? During the evolution of the human species, obesity was very rare. Hunter gatherers, even the few modern ones that remain in remote parts of the world are not fat. In evolutionary terms, weight loss meant that there was not enough to eat, so metabolic strategies to conserve calories during times of starvation had high survival value. The result is that when we lose a significant amount of weight, the body thinks we are starving. Several things happen to conserve energy. The first thing is that the basal metabolic rate or resting energy expenditure (REE) decreases an average of 50 kilocalories per day, but people who are obese to start with and lose a significant amount of weight can have decreases of REE as much as 700 kilocalories per day. Another body adaptation to weight loss is that the muscles become more efficient and use less fuel. This means that the calories you burn per hour with exercise decreases as you lose weight.

Appetite

As I mentioned before, the control of appetite is complex. Almost all control of appetite is unconscious. Appetite can be consciously controlled only for a short time, just as we can consciously control our breathing for a short time, but most breathing is (fortunately) unconscious. The part of the brain that controls our appetite and food intake is the hypothalamus. The hypothalamus secretes some hormones on its own and controls other hormones and/or peptides that both increase and decrease appetite. One hormone that increases appetite is Ghrelin. It is secreted by the stomach, small intestine, pancreas and brain and has multiple effects. It increases appetite and food intake and promotes fat storage. Hormones that makes you feel full or satiated are Leptin and GLP1. Control of appetite is actually a lot more complicated than this. Below is a table taken from a review article about hormonal control of appetite. Here is a link to the full article. It is not for the faint hearted. Hormonal Regulators of Appetite

The table summarizes what we know about the hormones and peptides that increase appetite and stimulate feeding and those that make us feel full and inhibit feeding. As you can see, control of hunger and satiety is very complicated. All of this takes place outside of our conscious awareness.

Hunger	Hormone	Primary location of production	Receptors	Action
Hypothalamus
	NPY	Medial arcuate nucleus (also widespread in CNS	Y1, Y5	Stimulating feeding and atagonizing satiety
	AgRP	Medial arcuate nucleus	MC3R and MC4R antagonist	Stimulating feeding
Peripheral Peptides
	Ghrelin	Stomach	GHS-R1a	Stimulating feeding by increasing NPY/AgRP and antagonizing Leptin effects
Satiety
Hypothalamus
	POMC/a–MSH	Arcuate nucleus	NC3R and MC4R	Inhibiting feeding, stimulating basal metabolic rate and altering nutrient partitioning
	CART	Arcuate nucleus		Inhibiting feeding
Peripheral peptides
	Cholecystokinin	Duodenum, jejunum	CCK-A	Inhibiting feeding and stimulating gall bladder contraction, intestinal motility, and inhibition of gastric motility
	PYY	Ileum, colon, rectum	Y2	Inhibiting feeding by inhibition of NPY and stimulation of POMC
	PP	Pancreas	Y4, Y5	Inhibiting feeding
	Oxyntomodulin	Distal ileum and colon	GLP-1 receptor	Inhibiting gastric acid secretion, decreasing gastric emptying and decreasing pancreatic enzyme secretion
	GLP-1	Distal ileum and colon	GLP-1 receptor	Delaying gastric emptying, stimulating glucose-dependent insulin secretion, inhibiting glucagon secretion and stimulating somatostatin secretion
	GIP	Stomach, duodenum, jejunum	GIP receptor	Glucose-dependent insulin secretion, induction of beta cell proliferation, promotion of energy storage, enhancement of bone formation
	Insulin	Pancreas	Insulin receptor	Inhibiting feeding
	Leptin	Fat cells	Leptin receptor, Ob-Rb	Inhibiting NPY and AgRP and stimulating POMC and CART
	Adiponectin	Fat cells	Adipo R1, R2	Inhibiting feeding

With significant weight loss (10% or more) the hormones that control appetite shift toward the hormones that make us hungry. Those includes Ghrelin, NPY and AGrP. The hormones that make us feel full, including leptin and others decrease.

The result of all this is that even if we are sure we are staying on the same foods, we are unconsciously eating more of them. The result is weight regain. The bad news is that 80% of people who lose weight on diets regain a substantial portion if not all of the weight they lost within 1-5 years. The good news is that 20% of people maintain most of the weight loss they achieved even after 5 years. How do those 20% of people who lost 10% or more of their body weight keep from regaining weight? We actually know a lot about how they do it.

National Weight Control Registry

Here is the introductory paragraph from the National Weight Control Registry website:

The National Weight Control Registry (NWCR), established in 1994 by
Rena Wing, Ph.D. from Brown Medical School, and James O. Hill, Ph.D.from the University of Colorado, is the largest prospective investigation of long-term successful weight loss maintenance. Given the prevailing belief that few individuals succeed at long-term weight loss, the NWCR was developed to identify and investigate the characteristics of individuals who have succeeded at long-term weight loss. The NWCR is tracking over 10,000 individuals who have lost significant amounts of weight and kept it off for long periods of time. Detailed questionnaires and annual follow-up surveys are used to examine the behavioral and psychological characteristics of weight maintainers, as well as the strategies they use to maintaining their weight losses.

The extensive research on the 10,000 people in the registry who have maintained weight loss show the following things that they do. This list is again from the registry website.

98% of Registry participants report that they modified their food intake in some way to lose weight.
94% increased their physical activity, with the most frequently reported form of activity being walking.
There is variety in how NWCR members keep the weight off. Most report continuing to maintain a low calorie, low fat diet and doing high levels of activity.
78% eat breakfast every day.
75% weigh themselves at least once a week.
62% watch less than 10 hours of TV per week.
90% exercise, on average, about 1 hour per day.

If you want to check out the registry for yourself, here is the link: The National Weight Control Registry

What all this research means is that it is possible to maintain weight loss despite the cascade of hormonal mechanisms that kick in to conserve calories when weight loss happens that work to get us back to the weight that we were. It is possible, but not easy. It takes continual effort, although people in the registry do report that it gets somewhat easier over time.

Bottom Line

All diets when adhered to result in weight loss
Some eating plans are sustainable and are not nutrient deficient. These include intermittent fasting, plant-based diets and the Mediterranean diet.
More extreme diets such as the Keto diet, VLCD diets and Paleo diet are not sustainable and have various nutrient deficiencies.
Substantial weight loss triggers hormonal changes in the body that conserve calories. These changes are responsible for the fact that weight loss plateaus on almost any diet and significant weight regain even often back to the original weight occurs in 80% of people who lose a substantial amount of weight.
It is possible to maintain weight loss over many years, but it is not easy. Findings from the National Weight Control Registry suggest the following strategies to maintain weight loss
- Maintain a low fat low calorie diet
- Exercise at least an hour a day
- Weigh yourself at least once a week
- Watch less than 10 hours of TV per week

Health Effects of Social Drinking: Risks and Impacts

Humans have been drinking beverages containing alcohol for well over a thousand years. Mild to moderate acute alcohol intake has a euphoric effect probably caused by release of dopamine in the brain. At lower blood levels alcohol promotes social interaction, which is likely why it has such a long history of use in human society. The actual effect of alcohol on the brain is complex and not well understood. Brain function is a delicate balance of excitatory and inhibitory neurotransmitters. Alcohol alters this balance in a complex way that is difficult to measure and characterize.

Addiction to alcohol occurs in some people. About half of alcohol addiction is genetically determined. Other causes include use to alleviate mental disorders such as anxiety or depression or psychosocial stress. Physicians used to use the term alcoholism to refer to alcohol addiction, but now the correct term is alcohol use disorder. This can range from mild to severe and is defined by NIH as a medical condition characterized by an impaired ability to stop or control alcohol use despite adverse social, occupational, or health consequences. Severe alcohol use disorder has major health and social consequences for both individuals and society.

In this post I’m not going to write further about alcohol use disorder. That is a subject unto itself. Instead I’m going to focus this post on the health effects of alcohol use that does not meet the definition of alcohol use disorder, so called “social drinking.”

Physicians used to say that a safe level of alcohol use was 2 drinks a day for a male and 1 drink a day for a female. Now physician advice is that no level of alcohol use is safe. Alcohol use has been shown to increase the risk of many cancers as well as heart disease. The real question is how big is the risk for these conditions and at what level of alcohol intake.

Measuring alcohol use

The term “drink” is not very precise. I once had a patient who insisted she only had one drink a day. Her one drink consisted of a 12 ounce glass of vodka. The UK has developed a different measure of alcohol intake called units of alcohol. One unit of alcohol is the amount an average person can metabolize completely in 1 hour. That amount is 10 cc (1/3 of an ounce) or 8 grams of pure alcohol. Here is a list of the number of units in beer, wine and cocktails:

Four ounce glass of wine (red or white) – 1.5 units
Six ounce glass of wine (red or white) – 2.1 units
Eight ounce glass of wine (red or white) – 3 units
Low alcohol pint of beer – 2 units
High alcohol pint of beer – 3 units
Bottle of beer – 1.7 units
Cocktails – 2.5-3 units

If you drink alcohol, add up the number of units you drink per week. The greater the number of units per week, the higher the risk, which I will quantify below. Be aware that most of these risks are very small. There are quite a few people who don’t drink at all or drink only rarely. These people simply don’t have any desire to drink alcohol or don’t like the way it makes them feel. These essentially non-drinkers form the comparison group for the risk of drinking alcoholic beverages.

Risk of Alcohol Use Disorder

The vast majority of social drinkers do not develop alcohol use disorder, but people who have a family history of alcohol use disorder are at greater risk if they start social drinking. Social drinking is also not a good idea for people with severe anxiety or depression.

Risk of Cancer

Drinking alcohol increases the risk of certain cancers, particularly colorectal cancer, breast cancer, liver cancer, esophageal cancer, and throat cancer. The total absolute cancer risk for drinking greater than 14 units of alcohol per week from age 25 to 85 is 4% for men and 5.4% for women. That translates to an annual risk of .0667% for men and .09% for women. To put that risk in perspective, the annual risk of death from a car accident in the US is .013%. and the annual injury risk from a car accident is 1%.

Risk of Death

In a large study in the UK, risk of death from all causes was associated only with drinking more than 42 units of alcohol per week.

Accelerated Ageing

Recent studies have looked at two measures of biologic ageing. At the end of each chromosome are structures called telomeres. It is known that these telomeres shorten as a person ages. The other measure is called epigenetics. These are non-DNA changes that are heritable. Some of these epigenetic changes increase as a person ages. Recent studies show an association between alcohol intake and these biologic ageing changes. There seems to be a dose response relationship. The more alcohol you drink, particularly liquor as opposed to beer and wine, the more your telomeres shorten and epigenetic changes accumulate. This association was most marked in people with alcohol use disorder. There was little association for light to moderate social drinkers. Association does not mean causation, however the researchers controlled for other things that might account for these changes like smoking, diabetes, and others. It is possible and even likely that these ageing changes were caused by alcohol intake.

Risk of Accidents

Even mild to moderate drinking impairs reaction time so driving after drinking any amount of alcohol is not a good idea. Heavier drinking causes more impairment of motor function and increases risk of accidents such as falls. Driving after heavier drinking markedly increases the risk of auto accidents, which can injure or kill others as well as the one who is drinking. Anyone who drinks any amount of alcohol outside the home should have a designated driver who agrees not to drink, or call Uber, Lift, or a taxi to be driven home.

Sleep Disturbance

Drinking alcohol, particularly later in the evening can cause sleep disturbance with early awakening and difficult getting back to sleep. This can occur even with light to moderate drinking.

Bottom Line

Drinking alcohol at all does increase the risk of cancer and heart disease. The annual risk is dose related, but is still very small for light and moderate drinkers (14-21 units per week) The risk of illness and death and accelerated ageing is higher for heavier drinkers, but still relatively small. Drinking alcohol later in the evening often causes sleep disturbance. This can usually be avoided by timing drinking alcohol in the late afternoon or early evening. The risk of cancer and heart disease from drinking is low but not zero. People who choose to drink alcohol are accepting that risk. Driving is not a good idea for any level of alcohol intake. Light to moderate drinking is definitely less risky than heavier drinking, which includes association with accelerated ageing as well as increased risk of auto accidents. These risks are still fairly small. People who have alcohol use disorder should seek professional help and strive to be completely abstinent from alcohol.