Skip to content


The controversy over whether people should be supplementing with vitamin D or not, and whether there are health benefits or harms from vitamin D supplementation is heating up. While observational studies have found health benefits with higher vitamin D blood levels, the beneficial results have generally not held up (or mixed findings) when people were randomly assigned to groups (randomized clinical trials). Most agree that blood levels of under 20 ng per mL is too low, but an issue is what is a desirable blood level? Should healthy people routinely supplement?

Having higher blood levels of vitamin D from sunshine appears to be good (it's the sunshine vitamin, after all). It's the taking of a vitamin D supplement that is now controversial and being debated. By the way, if one decides to take a vitamin D supplement, then the D3 form is desirable (rather than D2).

It was pointed out that a number of negative health effects can occur in those taking more than 4000 IU daily of vitamin D. For example, it may cause toxic effects such as renal impairment, hypercalcemia, or vascular calcification. In  2014, 3% of all U.S. adults and 6.6% of adults older than 60 years reported taking a vitamin D supplement of 4,000 or more IU per day. [See all vitamin D posts - most discuss observational studies finding benefits.]

The following are articles from Medscape (the medical site) and American Family Physician discussing recent research that is not finding health benefits with vitamin D supplementation, or mixed findings (e.g. one review found it may be protective in lowering death from any reason or from cancer; also reduce the number of upper respiratory infections)Therefore, some medical groups suggest that vitamin D screening is an unnecessary test, a waste of money,  and shouldn't be routinely done in healthy individuals. Note that many, many trials are going on right now to try to settle the vitamin D supplement issue (whether there are health benefits or not). ...continue reading "Mixed Findings In Vitamin D Supplement Studies"

Nice to hear that a new study found that across the lifespan, human brains are capable of producing new neurons (neurogenesis). Neurons are nerve cells, what we popularly call brain cells, and are the basic working unit of the nervous system. The human brain contains about 100 billion neurons.

The researchers did find some age differences (e.g. with age there was less neuroplasticity or the brain's ability to reorganize itself by forming new neural connections, and a decline in angiogenesis - the development of new blood vessels). But still... the findings are reassuring. Interesting how the researchers did the study. They examined 28 brains (specifically, newly formed neurons and the state of blood vessels within the hippocampus) right after death from previously healthy people (aged 14 to 79), who died suddenly.

While they found age differences, they did not find gender differences. The researchers summarized that healthy older subjects without cognitive impairment (meaning they were mentally healthy), neuropsychiatric disease, or treatment (e.g. depression drugs or psychotropic drugs) display preserved neurogenesis (produce new neurons) throughout life. From Science Daily:

Older adults grow just as many new brain cells as young people

Researchers show for the first time that healthy older men and women can generate just as many new brain cells as younger people.

There has been controversy over whether adult humans grow new neurons, and some research has previously suggested that the adult brain was hard-wired and that adults did not grow new neurons. This study, to appear in the journal Cell Stem Cell on April 5, counters that notion. Lead author Maura Boldrini, associate professor of neurobiology at Columbia University, says the findings may suggest that many senior citizens remain more cognitively and emotionally intact than commonly believed. ...continue reading "Some Good News About The Aging Brain"

This recent study adds to the body of knowledge of what negative major life events (resulting in lots of stress, anxiety, worry) does to a middle-aged person's health. Negative life events could be an interpersonal conflict (e.g. divorce), a death in the family, financial hardship, and serious medical emergencies. Using MRIs, the researchers found that each fateful life event (FLE), especially those that involve interpersonal relationships, accelerates brain aging about .37 years (about a third of a year). And the more negative life events, the bigger the effect. From Science Daily:

Negative fateful life events and the brains of middle-aged men

Conflict, a death in the family, financial hardship and serious medical crises are all associated with accelerated physical aging. In a new study, researchers at the University of California San Diego School of Medicine found that such negative fateful life events -- or FLEs -- appear to also specifically accelerate aging in the brain

Writing in the journal Neurobiology of Aging, a research team, led by senior author William S. Kremen, PhD, professor of psychiatry and co-director of the Center for Behavior Genetics of Aging at UC San Diego School of Medicine, found that major adverse events in life, such as divorce, separation, miscarriage or death of a family member or friend, can measurably accelerate aging in the brains of older men, even when controlling for such factors as cardiovascular risk, alcohol consumption, ethnicity and socioeconomic status, which are all associated with aging risk. 

Specifically, they found that on average, one FLE was associated with an increase in predicted brain age difference (PBAD) of 0.37 years. In other words, a single adverse event caused the brain to appear physiologically older by approximately one-third of a year than the person's chronological age, based upon magnetic resonance imaging (MRI). 

The researchers studied 359 men, ages 57 to 66 years old, participating in the Vietnam Era Twin Study of Aging (VETSA). Researchers asked participants to tally a list of life-changing events over the past two years .... All participants underwent MRI exams and further physical and psychological assessments within one month of completing the most recent self-reports. The MRIs assessed physiological aspects of the brain, such as volume and cortical thickness -- a measure of the cerebral cortex or outer layer of the brain linked to consciousness, memory, attention, thought and other key elements of cognition.

Hatton said exposure to chronic stress has long been associated with biological weathering and premature aging, linked, for example, to oxidative and mitochondrial damage in cells, impaired immune system response and genomic changes. The study's authors said their findings provide a possible link between molecular aging and brain structure changes in response to major stressful life events. They do note that the study was a snapshot of a narrow demographic: older, predominantly white, males. It is not known whether females or other ethnicities would show similar findings.

Of course! The results of this study made perfect sense to me - that losing your wealth or savings in late middle-age is such a mental shock ("negative wealth shock") that it increases the risk of death for any reason ("all cause mortality") tremendously over the next 20 years. About 50% increased risk of death. For example, if you have to live off your savings after you get laid off or can't work due to illness, and perhaps even lose your house to foreclosure, is STRESSFUL beyond belief. Almost incomprehensible to anyone who has not personally gone through it.

On top of that, a person may then not be able to afford to go to the doctor, even if there is a problem, once they're financially stressed. And of course they may never financially recover because the "negative wealth shock" happened at an older age (the people were 51 to 61 at the start of the study).

Other research conducted at time of the Great Recession showed significant associations between negative wealth shocks and short-term health changes - including increased risk of depression, anxiety, suicide, impaired cardiovascular function, and substance abuse. And now we know that long-term there is an increased risk of death. From Science Daily:

Losing your nest egg can kill you

A sudden loss of net worth in middle or older age is associated with a significantly higher risk of death, reports a new Northwestern Medicine and University of Michigan studyWhen people lose 75 percent or more of their total wealth during a two-year period, they are 50 percent more likely to die in the next 20 years, the study found.  ...continue reading "Losing Your Wealth In Late Middle-Age and Increased Risk of Death"

The last post dealt with the link between highly processed food and increased risk of cancer. Now an interesting article written by Dr. Lisa Mosconi (Associate Director of the Alzheimer’s Prevention Clinic at Weill Cornell Medical College/New York -Presbyterian Hospital) refers to that study when discussing research about lifestyles (and especially diet) and later Alzheimer's disease.

It'll be interesting to see how this research plays out - is her approach stressing diet (and avoiding ultra-processed food and trans fats) and lifestyle correct or not? Much of what she says definitely makes sense and is supported by research, such as the negative health effects of chronic inflammation, and how eating actual, real foods has beneficial health effects. On the other hand, vitamin, mineral, and fish oil supplements generally don't show those health benefits (as she discusses here).

Currently there are a number of theories about causes of Alzheimer's disease (including the role of microbes), as well as a number of drug treatments that so far have gone nowhere. If Dr. Mosconi's research interests you, then read the interview she did in 2017. [In the interview she talks about the importance of exercise, intellectual stimulation, social networks, and the benefits of eating real foods rather than supplements. She recommends: drink water, eat fish, eat vegetables and fruit, eat glucose rich foods, and don't eat highly processed and fast foods.]  From Quartz:

The road to Alzheimer’s disease is lined with processed foods

Dementia haunts the United States. There’s no one without a personal story about how dementia has touched someone they care for. But beyond personal stories, the broader narrative is staggering: By 2050, we are on track to have almost 15 million Alzheimer’s patients in the US alone. ... It’s an epidemic that’s already underway—but we don’t recognize it as such. The popular conception of Alzheimer’s is as an inevitable outcome of aging, bad genes, or both.  ...continue reading "Ultra-Processed Foods and Alzheimer’s?"

A recent study published in BMJ (British Medical Journal) found a link between high consumption of ultra-processed food and higher rates overall of cancer, but also a higher risk of breast cancer. Specifically, a 10% increase in the proportion of ultra-processed foods in the diet was associated with a greater than 10% increase of overall cancer and 11% increase of breast cancer during the 6+ years of the study.

Alarmingly (because of the health implications), several surveys (in Europe, the US, Canada, New Zealand, and Brazil) have suggested that ultra-processed food products are now between 25 to 50% of calories eaten every day.

Ultra-processed food is food that is highly processed. It is food that is mass produced and packaged, as well as foods that have manufactured substances in them - such as hydrogenated oils (also contains trans fats), protein isolates, additives, preservatives, artificial or natural flavors, colors, nitrites (in processed meat), titanium dioxide (nanoparticles), etc. The food packaging can leach chemicals such as pthalates (endocrine disruptors). The list goes on and on and on. All of these things in ultra-processed foods may be involved in causing health problems, including cancer. They are typically also poorer nutritionally and higher in salt than unprocessed or minimally processed foods. These ultra-processed foods that are so popular are all around us - in fast food, in mass produced desserts and breads, packaged snacks, soups, cold cuts, margarine, frozen or shelf stable ready to eat meals, instant foods, sodas and drinks, etc.

On the other hand, unprocessed or minimally processed foods are fresh, dried, ground, chilled, frozen, pasteurised, or fermented foods such as fruits, vegetables, legumes (beans), rice, pasta, eggs, meat, fish, or milk. There are also “processed culinary ingredients”  which are salt, vegetable oils, butter, sugar, and other substances extracted from foods and used in kitchens to transform unprocessed or minimally processed foods into "culinary preparations" (meals). The study did NOT find any association with unprocessed, minimally processed, or processed culinary ingredients with cancer. Only with the ultra-processed food. Instead, the study found that higher consumption of “minimally/unprocessed foods” (and lower ultra-processed food) was associated with lower risks of overall cancer and breast cancer.

So an apple is unprocessed, and plain apple sauce made with just apples is minimally processed, while a packaged apple dessert with additives added is ultra-processed. Think of it as "transformed food". Also keep in mind that your beneficial gut microbes like unprocessed or minimally processed food - especially those high in fiber. You know - a diet rich in fruits, vegetables, whole grains, seeds, nuts, legumes (beans).  ...continue reading "Ultra-Processed Food and Risk of Cancer"

A number of recent studies and articles have discussed the effectiveness of diet in treating or preventing depression with the main conclusion that yes, it helps. Now an observational study (that will be presented in April) found that elderly people following the DASH diet most closely were 11% less likely to become depressed over time than those that did not.

Researchers studying 964 elderly participants over six and a half years found that those who followed the DASH diet, which emphasizes whole grains, fruits, and vegetables, had lower rates of depression, while those who ate a traditional Western diet were more prone to depression. The DASH (Dietary Approaches to Stop Hypertension) diet also emphasizes low sodium (salt) to lower blood pressure, as well as foods rich in nutrients (such as potassium, calcium, and magnesium) that are thought to lower blood pressure.

The study's lead author L. J. Cherian (at Rush Medical Center in Chicago) said that "we need to view food as medicine”. Yes. Eating more fruits and vegetables, whole grains, legumes, seeds, nuts have many health benefits (such as cardiovascular benefits, improving the gut microbes) -  a win-win. From Science Daily:

Diet shown to reduce stroke risk may also reduce risk of depression

People who eat vegetables, fruit and whole grains may have lower rates of depression over time, according to a preliminary study that will be presented at the American Academy of Neurology's 70th Annual Meeting in Los Angeles, April 21 to 27, 2018. The study found that people whose diets adhered more closely to the Dietary Approaches to Stop Hypertension (DASH) diet were less likely to develop depression than people who did not closely follow the diet. In addition to fruit and vegetables, the DASH diet recommends fat-free or low-fat dairy products and limits foods that are high in saturated fats and sugar. Studies have shown health benefits such as lowering high blood pressure and bad cholesterol (LDL), along with lowering body weight ...continue reading "DASH Diet Linked To Lower Rate of Depression"

Study after study has found negative health effects from frequent heavy drinking of alcohol, including a number of cancers. On the other hand, light to moderate drinking seems to have some health benefits (here and here). Recently a large study conducted in France found that chronic heavy drinking, which has resulted in alcohol use disorders (alcohol abuse, alcohol dependence, or alcoholism), is the biggest risk factor for developing dementia, especially early onset dementia. Only people with alcohol use disorders which resulted in them being hospitalized were included in the study.

But the surprising thing was that lower levels of "chronic heavy drinking" doesn't seem so much - it's daily consumption of more than 60 grams of pure alcohol  for men, and more than 40 grams of pure alcohol for women. In the United States, a standard drink contains about 14 grams of alcohol - which is a 12 ounce (350 ml) glass of beer, a 5 ounce (150 ml) glass of 12% wine, or a 1.5 ounce (44 ml) glass of spirits. In other words, drinking 3 glasses of wine daily (or more) is heavy drinking for a woman. (Note: The Centers for Disease Control (CDC) views moderate drinking as 1 glass of wine daily for women, and 2 glasses of wine daily for men).  ...continue reading "Heavy Drinking And Risk of Dementia"

A new observational study from Taiwan found that having one of eight chronic diseases, such as heart disease or diabetes, or their markers (e.g. high cholesterol levels as a marker for heart disease), also significantly raises the person's odds of developing cancer or dying from cancer. The study estimated that these diseases or markers accounted for about 20% of all new cancers and 39% of all cancer deaths. That's about the risk of 5 lifestyle factors combined (smoking, alcohol consumption, obesity, unhealthy diet, and lack of exercise) contributing to cancer development and death.

The eight chronic diseases and markers were: cardiovascular disease (markers for which include blood pressure, total cholesterol, and heart rate), diabetes, chronic kidney disease (markers for which include proteinuria and glomerular filtration rate), pulmonary disease, and gouty arthritis (for which uric acid is a marker). The higher the chronic disease and marker score, the higher the risk of developing cancer and cancer death (a dose-response). Chronic diseases and markers were associated with a shortened lifespan -  about 13.3 years in men and 15.9 years in women.

But the good news is that regular physical exercise lowers the risk of developing cancer by about 48% and the risk of cancer death by 27%. That's huge!  So physical exercise and activity could be viewed as "cancer prevention" strategies. The researchers pointed out that additional cancer prevention strategies are avoiding smoking (very important), avoiding excessive alcohol consumption, maintaining healthy weight, and a healthy diet. From Science Daily:

Substantial impact of chronic diseases on cancer risk

Several common chronic diseases together account for more than a fifth of new cancer cases and more than a third of cancer deaths, finds a study published by The BMJ today. The findings show that the cancer risks from common chronic diseases, such as heart disease and diabetes, are as important as those from five major lifestyle factors combined.

A team of researchers based in the US and Taiwan therefore set out to investigate the combined effect of eight common chronic diseases or disease markers (for example, high blood pressure as a marker of heart disease) on cancer risk compared with lifestyle factorsThey also explored whether physical activity could reduce the cancer risk associated with chronic diseases and disease markers. The study involved 405,878 men and women in Taiwan with no history of cancer .... underwent a series of medical tests between 1996 and 2007. .... Participants were followed for an average of 8.7 years.

The researchers found that cardiovascular disease markers, diabetes, chronic kidney disease markers, pulmonary disease, and gouty arthritis marker were individually associated with risk of developing cancer or cancer death. Higher chronic disease risk scores based on these diseases or markers were linked with an increased risk of developing cancer and cancer death, with the highest level associated with a more than twofold increase in risk of developing cancer and a fourfold increase in risk of cancer death.

High chronic disease risk scores were also associated with substantial reduction in life span. The highest scores were associated with 13.3 years of life lost in men and 15.9 years of life lost in women. Together, these chronic diseases and markers accounted for more than one fifth of all new cancers and more than one third of all cancer deaths in this study population, which was similar to the contribution of five major lifestyle risk factors combined -- smoking, insufficient physical activity, insufficient fruit and vegetable intake, alcohol consumption, and obesity.

The researchers also found that physical activity was associated with a nearly 40% reduction in the excess risks of cancer and cancer death associated with chronic diseases and markers. [Original study.]

Interesting new research found health benefits to the brain from daily low intake of alcohol (equivalent to about 2 1/2 drinks per day). The University of Rochester (in New York) researchers found that while low daily (chronic) levels of alcohol were beneficial to the brain's glymphatic system, higher daily levels or binge drinking was not. And the low daily levels of alcohol intake was also better for the glymphatic system than no alcohol at all (the control group). In 2015 this same research team described the glymphatic system as not just the brain’s “waste-clearance system,” but as potentially helping fuel the brain by transporting glucose, lipids, amino acids, and neurotransmitters.

I'm sure this study will be greeted by many as great news, but remember it was done with MICE, and not humans, so one should be cautious in generalizing the results. But the researchers think that it does apply to humans, and may explain why some studies find some health benefits to low levels of daily alcohol intake, even better than no alcohol, and many negative effects to higher levels of alcohol intake - thus the J-shaped curve of effects seen in studies. [NOTE: Studies also find that alcohol consumption can cause cancer, and this is dose related. Studies find the Mediterranean diet (which includes low to moderate levels of alcohol) beneficial for brain health.]

By the way - no, the mice didn't receive wine as the press release from the Univ. of Rochester says. The mice actually received "intraperitoneal injections of low, intermediate, and high doses of ethanol" or just plain saline (the control group). From Science Daily:

In wine, there's health: Low levels of alcohol good for the brain

While a couple of glasses of wine can help clear the mind after a busy day, new research shows that it may actually help clean the mind as well. The new study, which appears in the journal Scientific Reports, shows that low levels of alcohol consumption tamp down inflammation and helps the brain clear away toxins, including those associated with Alzheimer's disease.

"Prolonged intake of excessive amounts of ethanol is known to have adverse effects on the central nervous system," said Maiken Nedergaard, M.D., D.M.Sc., co-director of the Center for Translational Neuromedicine at the University of Rochester Medical Center (URMC) and lead author of the study. "However, in this study we have shown for the first time that low doses of alcohol are potentially beneficial to brain health, namely it improves the brain's ability to remove waste." The finding adds to a growing body of research that point to the health benefits of low doses of alcohol. While excessive consumption of alcohol is a well-documented health hazard, many studies have linked lower levels of drinking with a reduced risk of cardiovascular diseases as well as a number of cancers.

Nedergaard's research focuses on the glymphatic system, the brain's unique cleaning process that was first described by Nedergaard and her colleagues in 2012. They showed how cerebral spinal fluid (CSF) is pumped into brain tissue and flushes away waste, including the proteins beta amyloid and tau that are associated with Alzheimer's disease and other forms of dementia. Subsequent research has shown that the glymphatic system is more active while we sleep, can be damaged by stroke and trauma, and improves with exercise.

The new study, which was conducted in mice, looked at the impact of both acute and chronic alcohol exposure. When they studied the brains of animals exposed to high levels of alcohol over a long period of time, the researchers observed high levels of a molecular marker for inflammation, particularly in cells called astrocytes which are key regulators of the glymphatic system. They also noted impairment of the animal's cognitive abilities and motor skills.

Animals that were exposed to low levels of alcohol consumption, analogous to approximately 2 ½ drinks per day, actually showed less inflammation in the brain and their glymphatic system was more efficient in moving CSF through the brain and removing waste, compared to control mice who were not exposed to alcohol. The low dose animals' performance in the cognitive and motor tests was identical to the controls.

"The data on the effects of alcohol on the glymphatic system seemingly matches the J-shaped model relating to the dose effects of alcohol on general health and mortality, whereby low doses of alcohol are beneficial, while excessive consumption is detrimental to overall health" said Nedergaard. "Studies have shown that low-to-moderate alcohol intake is associated with a lesser risk of dementia, while heavy drinking for many years confers an increased risk of cognitive decline. This study may help explain why this occurs. Specifically, low doses of alcohol appear to improve overall brain health." [Original study. Especially interesting is the Introduction & Discussion sections.]