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A few weeks ago I posted research about the nutrient choline and discussed its importance for brain health. Now Dr. Emma Derbyshire in the United Kingdom has written a piece in the current issue of the journal BMJ Nutrition, Prevention & Health about the necessity of choline in the diet and the health dangers of this nutrient being neglected, especially in people following plant based or vegan diets.

Choline is an essential nutrient that cannot be produced by the body in amounts needed for human requirements. Good sources of choline are meat, dairy products, poultry, and eggs, and it appears that eggs (the egg yolks) are especially beneficial.

From Medical Xpress: Suggested move to plant-based diets risks worsening brain health nutrient deficiency

The momentum behind a move to plant-based and vegan diets for the good of the planet is commendable, but risks worsening an already low intake of an essential nutrient involved in brain health, warns a nutritionist in the online journal BMJ Nutrition, Prevention & Health.  ...continue reading "Don’t Neglect the Nutrient Choline"

A new large study found that eating a flavonoid rich diet is associated with a lower risk of death. Flavonoids are compounds found in abundance in plant derived foods and beverages, such as fruits, vegetables, dark chocolate, tea, legumes, and red wine. The study followed about 56,000 people in Denmark for 23 years and found that eating higher levels of flavonoid rich foods was associated with a lower risk of death from any cause (all-cause mortality), heart disease (cardiovascular disease), and cancer.

The researchers found that there was an inverse relationship (the more one eats, the lower the risk of death), and that this relationship was strongest among cigarette smokers and people who consume high amounts of alcohol (more than 20 grams per day). Bottom line: Make sure your diet includes lots of fruits, vegetables, legumes, and dark chocolate (yes!).

By the way, while other studies do find a lower incidence of heart disease and cancer in people eating a diet rich in flavonoids, in this study they were not looking at who got the diseases, but looked at deaths. Therefore the following title is misleading. It should instead say "... protects against cancer and heart disease deaths..." From Science Daily: Flavonoid-rich diet protects against cancer and heart disease, study finds  ...continue reading "Eating Foods Rich In Flavonoids Has Health Benefits"

Back in 2015 and 2016 some studies found a link between taking medicines that are anticholinergic and cognitive decline and dementia. Some examples of non-prescription anticholinergic medications are Chlor-Trimeton, Benadryl, Tavist, and Dimetapp. During this time a person also contacted me to report that his relative, who had Down's syndrome, had once participated in a study where he received cholinergic therapy, with the result that during the study he functioned better neurologically. Meanwhile I read several studies of older people that supported the result of a higher intake of foods with choline and better neurological functioning (e.g. verbal and visual memory).

A recent large study of men over a 4 year period found an association between a  higher intake of foods with choline (dietary choline) and better performance on several cognitive tests and lower risk of dementia. The research, which was conducted in Finland, found that the relationship seemed especially strong for a type of choline called phosphatidylcholine. Eggs (specifically the egg yolks) are a primary dietary source of phosphatidylcholine, and indeed, in the study, higher egg intake was associated with better performance on several measures, including verbal fluency, as well as lower risk of dementia.

Choline is an essential nutrient, found in some foods. Its role in the body is complex, but one of its roles is to produce acetylcholine, an important neurotransmitter for memory, mood, muscle control, and other brain and nervous system functions (NIH choline fact sheet). On the other hand, anticholinergic medications block the action of the neurotransmitter acetylcholine (which is involved with learning and memory). Anticholinergic medications include many common drugs, such as some antihistamines, sleeping aids, tricyclic antidepressants, medications to control overactive bladder, and drugs to relieve the symptoms of Parkinson’s disease.

What should one do? First, make sure to eat some foods rich in choline, especially eggs. The researchers themselves say that "consuming an adequate amount of foods high in choline may be an easy, effective, and affordable way to maintain cognitive functioning". Good sources of choline are meat, dairy products, poultry, and eggs - and it appears that eggs (the egg yolks) are especially beneficial. Second, one should also try to avoid non-prescription and prescription medicines known to be anti-cholinergic. For example switch from allergy medicines diphenhydramine or chlorpheniramine (Chlor-Trimeton) to one that isn't anticholinergic. [See list.]

From Science Daily: Dietary choline associates with reduced risk of dementia  ...continue reading "The Choline In Eggs Is Beneficial For the Brain"

Are we looking at vitamin D and sunlight the wrong way? Back in 2016 I posted about the results of a long-running Swedish study that made me rethink everything I knew about sunlight and health. (The prevailing view of dermatologists at the time and now is: to always use sunscreen if going outdoors in order to lower the risk of skin cancer. In other words, that sunlight is always harmful.)

The Swedish study followed women for 20 years and found that: Women who had more sunlight exposure experienced a lower mortality rate than women who avoided sun exposure. However, they were at an increased risk of skin cancer. But those with more sun exposure lived longer due to a decrease in heart (cardiovascular) disease and other noncancer reasons. And the most surprising finding: Nonsmokers who avoided sun exposure had a similar life expectancy as smokers with the highest sun exposure. In other words: avoidance of sun exposure = cigarette smoking when looking at life expectancy. And the results of sun exposure was dose-dependent, with the more, the better for longer life expectancy.

The researchers suggested that  a person's vitamin D levels might be just a marker of sun exposure, which other studies and articles now also suggest. So while we measure vitamin D levels in studies, maybe we should instead be looking at sunlight exposure.

Since then I read more studies that found other benefits of sunlight exposure, such as sunlight having low levels of "blue light" which energizes T cells. T cells are a type of white blood cell, are part of the immune system, and help protect the body from infection and cellular abnormalities (cancer). An earlier study found that exposing skin to sunlight may help to reduce blood pressure and thus cut the risk of heart attack and stroke.

This year I read the following two nicely written articles about this whole issue, both a little different - so worth reading both to get a good idea about the research and the debate.

1) From Outside: Is Sunscreen the New Margarine?

2) From Elemental Medium: What If Avoiding the Sun Is Bad for You?

And once again, a link to the 20 year Swedish study, from the Journal of Internal Medicine: Avoidance of sun exposure as a risk factor for major causes of death: a competing risk analysis of the Melanoma in Southern Sweden cohort

A recent large study found that getting high levels of vitamin D from foods, but not supplements, is linked to a lower rate of a common skin cancer (squamous cell carcinoma) years later. Once again: the beneficial health effect is associated with eating real foods, but not supplements.

Researchers found an inverse relationship with vitamin A intake and squamous cell carcinoma - those that had the highest dietary intake of vitamin A had a 17 % reduction of the skin cancer during the next 26 years. The inverse associations were highest among those with moles and those who had sunburns during childhood or adolescence.

The high intake group had the vitamin A amount equivalent to one medium baked sweet potato or 2 large carrots each day. Most of their intake came from fruitsand vegetables. Vitamin A (retinoids) is important in keeping skin cells healthy, and retinoids are considered cancer protective (or anticancer) for several cancers.

What foods are high in vitamin A?  Plant-based sources of vitamin A (carotenoids, including lutein and lycopene) include orange and yellow fruits  and vegetables, such as sweet potatoes, carrots, butternut squash, pumpkin, apricots, cantaloupe, red peppers, tomatoes, as well as broccoli, spinach, and leafy dark vegetables. Animal based sources of vitamin A  (retinol) are dairy foods (milk, cheese, yogurt), eggs, some types of fish (e.g. herring), and beef liver. (More information at National Institutes of Health.)

From Futurity: CAN GETTING MORE VITAMIN A CUT SKIN CANCER RISK?  ...continue reading "Vitamin A and Skin Cancer Risk"

The evidence is growing. Another recent study found that exposure to dirt and animals in the first year of life is beneficial for development of a a rich and diverse gut microbiome - that is, for greater species "richness" as well as more beneficial microbes. This is linked to lower levels of allergies and asthma in children.

So don't worry about children being exposed to animal "germs" and getting dirty! Instead, consider the microbes as having health benefits, such as developing a "robust immune system". In summary, it now appears that in the first year of life the immune system needs lots of exposure to all sorts of microbes (e.g. from pets, animals, dirt)  to "train it" to develop normally.

The Ohio State University researchers compared 5 healthy rural Amish infants to 5 healthy non-Amish urban infants in Ohio, also found that all of the rural (Amish) children were breastfed, while 2 of the urban (non-Amish) children were only formula fed (some microbial differences there). The Amish households had farm animals (cattle, sheep, and/or horses) and pets (dogs and/or cats), while the non-Amish households had no contact with livestock, but did have a pet dog or cat. Just like in other studies, one pet doesn't seem to be enough - even more animal exposure in early childhood is best for the gut microbiome. [One study found a dose-dependent effect with exposure to 5 furry pets in early childhood was needed to prevent all allergies.]

Studies find that rural (Amish) children have a low incidence of allergies and asthma, while urban children have a high incidence of allergies and asthma. In this study, an example of microbial differences in the 2 groups of children was that Bifidobacterium bacteria were "enriched" in non-Amish (urban) infants, while Roseburia species were "enriched" in Amish (rural, farm-raised) infants. Similar gut microbe differences have been observed in other studies comparing rural and urban children, and both dietary differences (e.g. farm raised children eat lots of homegrown produce) and environmental differences (animal exposure) are thought to be responsible for the differences.

From Science Daily: Keeping livestock in the yard just might help your baby's immune system  ...continue reading "Children, Animals, and Gut Microbes"

The Paleo diet has been around for years and yet it continues to be controversial. The debate is whether following the Paleo diet long-term has health benefits or not? Supporters of the Paleo (Paleolothic) diet say it promotes gut health and is good for gut microbes, but recent research findings are a strike against this claim. The Paleo diet is based on the hypothesis that humans have not adapted to eating products of agricultural farming such as grains, dairy products, or legumes (beans), as well as all processed foods, so they should be avoided. Instead it stresses eating meat, fish, eggs, nuts, (some) fruits, and vegetables.

So what were the new research findings?  Australian researchers found that people who had been on a Paleo diet for more than a year ate lower amounts of resistant starch, and so had a different bacteria profile in the gut - with lower levels of some beneficial species. They also had high levels of a biomarker in the blood (trimethylamine-n-oxide or TMAO) that is linked to heart disease.

The problem seems to be the lower intake of resistant starch - which is a carbohydrate that resists digestion in the small intestine and ferments in the large intestine. As the fibers ferment they act as a prebiotic and feed the beneficial bacteria in the gut. More than one type of resistant starch can be present in a single food. And what foods contain resistant starches? Precisely some foods avoided in the Paleo diet: grains, rice, beans, peas, lentils, plantains, and green bananas. A number of studies find health benefits (e.g. gut health) from eating foods with resistant starches.

From Medical Xpress: Heart disease biomarker linked to paleo diet

People who follow the paleo diet have twice the amount of a key blood biomarker linked closely to heart disease, the world's first major study examining the impact of the diet on gut bacteria has found.  ...continue reading "Problems With Paleo Diet?"

New research once again confirms that raw fruits and vegetables result in a person ingesting lots of microbes. Millions of bacteria. Which is considered beneficial for our gut microbiome! What's interesting in the latest study looking at bacteria in both conventionally and organically grown apples is that organic apples are a better source of bacteria - that their bacteria are more diverse, distinct, and balanced (when compared to conventionally grown apples).

The Austrian researchers (Wassermann et al) wrote in the Frontiers In Microbiology: "Our results suggest that we consume about 100 million bacterial cells with one apple. Although this amount was the same, the bacterial composition was significantly different in conventionally and organically produced apples."

Interestingly, there were a lot of beneficial Lactobacillus species in the organic apples, but not conventionally grown ones. The researchers thought that the diverse microbiome of organic apples probably limits or hampers harmful microbes (human pathogens). The researchers also wrote: "The described microbial patterns in organic apples resemble the impact of apple polyphenols on human health, which have not only been shown to alleviate allergic symptoms (Zuercher et al., 2010), but also to promote growth of Lactobacillus and Bifidobacterium in the human gut and to reduce abundance of food-borne pathogens."

Another bonus of eating organic apples is that it means avoiding pesticides that are routinely sprayed on conventional fruit. So eat away! Microbes, fiber, and nutrients all in one small fruit!

Fun fact: The researchers write that apples are the most consumed fruit world-wide. Excerpts from Science Daily: An apple carries about 100 million bacteria -- good luck washing them off  ...continue reading "Excellent Reason To Eat Apples: The Bacteria"

Once again research is finding effects on health from nanoparticles and air pollution - this time the heart. Tiny air pollution particles less than 100 nm (nanometers) in size are typically called "ultrafine  particles", but actually they are so small that they are nanoparticles. They are NOT regulated in the United States, even though many researchers feel that they are the most dangerous particles found in air pollution. This is because their small size means they are easily inhaled and then get into human lungs and organs, and even cells. Where do they come from? They get into the air from industry (e.g. metal processing, power generation plants), from the exhaust of vehicles (from vehicle combustion), and from friction when using vehicle brakes.

The researchers write that the air in polluted urban areas and next to roads have a lot of these iron-rich nanoparticles from vehicle combustion and friction. And also that these particles are "strongly magnetic". Earlier research in the urban Mexico City area found that these nanoparticles were found in the brains of all people, starting at young ages (they had died suddenly in accidents, which is why the brains could be analyzed). Keep in mind that Mexico City has high levels of air pollution, but so do many other urban areas throughout the world.

This latest study from a team of international researchers analyzed both the hearts of young people who died suddenly, as well as animals - and they compared the results from those exposed to high levels of urban air pollution (Mexico City metro area) and those from areas with low amounts of air pollution (the "controls"). The results were not good: all hearts from the Mexico City area (high air pollution) had lots of the same iron-rich magnetic nanoparticles ("in abundance") that are found in the air. Billions of nanoparticles in each heart, even in the youngest 3 year old child!

These nanoparticles are inhaled, then enter the person's circulatory system (carried by blood cells), and then into cardiac cells. As the researchers stated: the magnetic nanoparticles were "highly abundant in left ventricular samples from young subjects exposed to high concentrations of particulate air pollution above current US EPA standards. The organelles and structures containing abundant nanoparticles displayed substantial abnormality". Hearts from low pollution areas appeared normal.

This could explain why people living in polluted urban areas, including in the United States, have a greater risk for heart disease (cardiovascular disease), including heart attacks and strokes, as well as premature death. This research also highlights why we need to regulate these tiny particles in the air. As the researchers said: "This is a serious public health concern".

Excerpts from The Guardian: Billions of air pollution particles found in hearts of city dwellers   ...continue reading "Pollution Nanoparticles Found In Human Hearts"

We tend to think of our beds as a refuge from the outside world, where one can safely relax and sleep. Well... not quite. A recent study conducted in Israel analyzed chemicals released from youth and infant polyurethane mattresses and found that all the mattresses outgassed chemicals of concern (such as formaldehyde, toluene, benzene). These chemicals are called VOCs (volatile organic compounds) - they are chemical compounds released from products (e.g. mattresses) as vapor into the air, which we then breathe in. It is known that some VOCs have harmful health effects (e.g. eye and nose irritation, neurological effects, cancer) at high levels long-term. The researchers also found that a person's body heat on the mattress actually increases release of chemicals.

The one infant mattress tested also released flame retardants into the air. Of course no one really knows what breathing in low levels of these chemicals night after night for years does to us, if anything. But it should concern us. Keep in mind that during sleep our mouths and nostrils are very close to the mattress surface, so we are definitely breathing in whatever chemicals our mattresses emit. Researchers referred to the air around our beds as our sleeping microenvironment. And yes, our bedding (sheets, etc) also emit chemicals that they were treated with during manufacturing, such as formaldehyde in wrinkle-free sheets.

From Science Daily: Mattresses could emit higher levels of VOCs during sleep

Hundreds of household items, including furniture, paint and electronics, emit volatile organic compounds (VOCs), which at high levels can pose health risks. Now, researchers reporting in ACS' Environmental Science & Technology have measured the emission rates of the gaseous compounds released by several types of polyurethane mattresses under simulated sleeping conditions, finding levels of some VOCs that could be worrisome for children and infants. However, so far there is no evidence of adverse health effects.  ...continue reading "Mattresses Emit Chemicals"