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There have been a number of studies finding microplastics (tiny bits of plastic smaller than 5mm) in seafood, drinking water, many foods, as well as in the air we breathe (e.g. from the breakdown of vehicle tires and brakes during normal use). There has been some concern over what the microplastics are doing to us because so little research has been done. But there is worry that the smallest sized microplastics are entering our bodies, traveling to different organs, and causing damage. But at least some of the microplastics we ingest are traveling through the gastrointestinal system  and then excreted in our stool, according to a recent study.

The study had 8 healthy volunteers from Europe and Asia (United Kingdom, Italy, Japan, Poland, Russia, Netherlands, Finland, and Austria). keep a food dairy for a week, and then "donate" a stool sample which was analyzed. None of the volunteers were vegetarians, and 6 had consumed fish from oceans in that week. [Note: Studies find that seafood contains microplastics.]

The  stool samples were analyzed for 10 types of plastic. All the stool samples contained microplastics, with polypropylene and polyethylene terephthalate being the most abundant. The samples contained an average of 20 microplastic particles per 10 g of stool. Since 9 types of plastic was detected in the stool, the researchers say that means they come from multiple sources.

Recently Canadian researchers estimated that annual consumption of microplastics ranges from 39,000 to 52,000 particles (depending on age and sex). When they added in inhalation of microplastic particles, the numbers increased to 74,000 to 121,000. And those who only drink bottled water may be getting an additional 90,000 microplastics (versus about 4000 microplastics from tap water). Yikes!

What to do if this concerns you? Since plastic wrappers, containers, and bottles (including water bottles) shed microplastics, then one can try to purchase and store foods in plain cardboard or glass containers. Stainless steel containers are also OK (NOTE: aluminum cans are usually coated with suspect chemicals). Definitely drink more tap water, and less bottled water.

From Medical Xpress: Microplastics detected in human stool   ...continue reading "Microplastics Are Found In Human Stool"

A really interesting study found that in humans, taking antibiotics (which reduces the gut bacteria) may result in the flu vaccine not being as effective as in people who did not take antibiotics. An earlier similar study had found that this was true for mice, which is why the researchers did the study on humans.

The Stanford University and Emory University researchers studied healthy people who had recent (in last few years) flu vaccinations and those who hadn't had a flu vaccine for several years prior to the study. Some individuals took 5 days of broad spectrum antibiotics, and on day 4 received a flu vaccine, while others did not take antibiotics, but did receive the flu vaccine on day 4.

Not surprisingly: The antibiotics lowered the gut-bacterial population by 10,000-fold. While month by month there was increasing recovery, the resulting loss of overall diversity was detectable for up to one year after the antibiotics were taken. Keep in mind that they found that: "Notably, species richness and biodiversity were not fully recovered at 6 months, indicating long-lasting loss of unique bacterial species, consistent with previous studies." [BOTTOM LINE: Only take antibiotics when necessary.]

Interestingly, after antibiotic use, the researchers found other changes besides an alteration in gut bacteria populations. They also found changes within the immune system which resulted in an inflammatory state, which was due to "impairments in bile acid metabolism by the gut flora". In other words, taking antibiotics has a number of effects beyond treating an infection (the reason they were taken).

By the way, those who had taken flu vaccines in prior years had much better responses to the vaccines - they only had a minimal impact on vaccine response, even though they took antibiotics, than those who had not. Those who had not received flu vaccines or the flu in recent years had "low preexisting immunity", and taking the antibiotics (which resulted in loss of gut bacterial species) impaired their antibody response to the flu  vaccine. The researchers said: "The results of this study are consistent with the concept of immune responses in adults being largely determined by immune history and resilient to transient changes in the microbiome."

From Medical Xpress: Individual response to flu vaccine influenced by gut microbes   ...continue reading "Antibiotics, Flu Vaccines, and Gut Bacteria"

This actually may seem obvious to many: that older people cope better in terms of loneliness and depression after a spouse's death or divorce if they have at least 1 pet cat or dog (versus no pets), but it's good to read that an actual study supported this. Other studies support that in general, a companion animal is beneficial for psychological health

The researchers called the pet a "companion animal" and wrote: "In later life, companion animal ownership may buffer against the detrimental consequences of major social losses on psychological health." In the study, depression is measured by  the "depressive symptoms" a person has.

From Medical Xpress: The pet effect: Researchers find furry friends ease depression, loneliness after spousal loss  ...continue reading "Pets Can Help With Loneliness and Depression Following Loss of a Spouse"

Today's post is in response to people asking me about climate change and what it means for the earth. A great book on this topic that was published this year and has received excellent reviews by the NY Times, scientists, and others  is The Uninhabitable Earth: Life After Warming. Written by David Wallace-Wells and published by Tim Duggan Books in 2019. David Wallace-Wells is a columnist and deputy editor of New York magazine, and a national fellow at the New America foundation.

This book is a wake-up call about the dangers of not responding (or not responding enough) to the climate change crisis and what will happen if we don't treat it as an emergency, which it is. The book's first sentence is: "It is worse, much worse, than you think." And then he lays it out for us in detail - the horrors that will happen if we do nothing, or not enough. Descriptions of what we can realistically expect within a few years or decades from climate change and global warming. And yes, there are many scientific references listed - over 200.

Two years ago David Wallace-Wells published an article in New York magazine abut this same topic titled: The Uninhabitable Earth Famine, economic collapse, a sun that cooks us: What climate change could wreak — sooner than you think. The article went viral, was discussed extensively, and got many people talking about climate change as a "climate emergency" or a "climate change crisis".

"Indeed, absent a significant adjustment to how billions of humans conduct their lives, parts of the Earth will likely become close to uninhabitable, and other parts horrifically inhospitable, as soon as the end of this century."

At the beginning of the article is a link to an annotated version of the article, with a full discussion of references and scientists adding their comments to the article.

Both the article and book are absolutely, totally worth reading. Just be warned: it will not be easy reading because  the consequences of not doing enough, or of ignoring the problem, are so bad for the world and all of us.

NY Times review about the book: Two New Books Dramatically Capture the Climate Change Crisis

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"