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The results of a recent study makes sense - that different microbes are found in city and town apartments and homes versus rural homes and jungle huts. And of course one would expect these different exposures to have an effect on our health. Guess where one gets more fresh air and sunlight, and where one has more chemical exposures?

Inside modern city and town buildings is lots of exposure to all sorts of plastics, human made chemicals, cleaners (and disinfectants), pesticides, medications, lack of fresh air, and along with lack of sunlight - all sorts of fungi. On the other hand, in rural areas there is fresher air, more sunlight, and more natural materials. [Remember: it's plastics and modern chemical compounds that outgas into the air and are a cause of air pollution. And yes, get into our bodies and affect our health negatively.]

The study was conducted in Peru and Brazil by several big names in the microbiome field, including Martin Blaser, Rob Knight, and Maria Dominguez-Bello. As the researchers point out, we have replaced a natural environment with a synthetic environment. Bottom line: get out into nature as much as possible, even if it's just walks. Try to use natural materials in your home (e.g., wood and not just plastic furniture), try to use "natural" products, and fewer chemicals routinely (pesticides, disinfectants, etc)

From Futurity: More Fungi Live In Urban Homes Than In Jungle Huts  ...continue reading "Different Microbes Live In Urban Homes Versus Really Rural Homes"

Researchers in Canada found that sunlight (or UVB light) on the skin changes the gut microbes (gut microbiome), especially in people with lower levels of vitamin D, that is, who are vitamin D deficient. UVB (Ultraviolet B light) exposure increased beneficial gut microbe diversity and richness in these people, as well as increasing their vitamin D levels. However, people who had been taking vitamin D supplements prior to the study, and who had sufficient vitamin D levels, did not have significant gut microbiome changes.

The researchers viewed the study results as evidence that there may be a skin-gut axis. As the researcher Vallance said: “It is likely that exposure to UVB light somehow alters the immune system in the skin initially, then more systemically, which in turn affects how favorable the intestinal environment is for the different bacteria,” suggested Vallance.

The researchers also thought that these study results (which was conducted in Vancouver, Canada, in healthy human volunteers) could help explain the protective effect of UVB light against inflammatory diseases such as multiple sclerosis (MS) or inflammatory bowel disease (IBD). And how did the researchers know what bacteria were in the gut in the study participants? They analyzed the feces with modern genetic sequencing methods. By the way, these results match what has been found in earlier studies in humans and mice.

Bottom line: Sunlight on the skin is beneficial to the gut microbiome, by increasing gut bacteria linked to health. In the study the increases in bacteria (after UVB light exposures) were in the Lachnospiraceae, Ruminococcus, and Clostridiaeae families. And nope, none of those are found in currently available probiotics. By the way, this study was conducted in winter in Canada, so the effects of UVB light were clearly seen in the healthy volunteers. This study supports getting some sunlight exposure (on the skin), and perhaps supplementing with vitamin D in the winter.

From Medical Xpress: Where the sun doesn't shine? Skin UV exposure reflected in poop  ...continue reading "Exposure To Sunlight Improves Gut Microbes and Vitamin D Levels"

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Researchers are starting to raise concerns about routine daily intake of probiotics for "gut health". Much is still unknown, but problems are starting to appear. A healthy gut contains hundreds of species (bacteria, fungi, viruses), and taking megadoses of a few species (a probiotic supplement) can overwhelm the normal gut microbial community. A healthy gut is one with a greater diversity of species, not just some species.

For example, one study found that daily probiotic ingestion can result in overgrowth of some bacterial species in the intestines, resulting in such symptoms as brain fogginess, bloating, and gas. Successful treatment was antibiotics and stopping the use of probiotics.   Another recent study found that after using antibiotics, those who took probiotics (thinking it would help microbial recolonization of the gut microbes) actually had slower recovery of the gut microbiome (microbial community).  The best recovery was in those who took nothing, no supplements at all, or those who received a fecal microbial transplant (where an entire microbial community is transplanted).

The evidence is showing that for gut microbial health, the best thing to do is eat a variety of real whole foods (and not highly processed foods) that have lots of fiber, such as whole grains, fruits, vegetables, seeds, nuts, and legumes (beans). In other words, feed the beneficial bacteria. A Mediterranean style diet is good.

A recent article in Medscape (the medical site) highlights these same concerns. [See below.] A study that looked at the gut microbiome of people who were about to undergo treatment for melanoma found that those who were taking probiotics actually had worse gut microbial diversity. [Remember, gut microbial diversity is considered an indicator of gut health.] And the cancer treatment (immunotherapy) did not work as well on them.

Bottom line: The evidence is showing that for gut microbial health, the best thing to do is eat a variety of real whole foods (and not highly processed foods) that have lots of fiber, such as whole grains, fruits, vegetables, seeds, nuts, and legumes (beans). In other words, feed the beneficial bacteria. A Mediterranean style diet is good. Don't take routine daily supplements or probiotics for  "gut health" - they won't help. Instead, if you want - only take probiotics for a short while for a specific symptom or problem.

Dr. Lorenzo Cohen wrote a piece for the Wall Street Journal laying out those same points. Some excerpts from: Those Probiotics May Actually Be Hurting Your ‘Gut Health’  ...continue reading "Daily Use of Probiotics Can Hurt Gut Health"

The evidence is building, study by study, that we are all exposed to a mixture of hormone disrupting chemicals (endocrine disruptors) on a daily basis, and that these have serious health effects, including on the developing fetus during pregnancy. Researchers found that early prenatal exposure to a mixture of endocrine disrupting chemicals  was associated with lower levels of cognitive functioning (lower IQ scores) at age seven, particularly among boys.

Researchers in New York City and Sweden looked at the impact of 26 endocrine disrupting chemicals during pregnancy on 718 Swedish mother-child pairs. It appeared that the higher the exposure during pregnancy, the more of an effect at age 7. Especially harmful was the BPA replacement chemical BPF - this is because it is chemically related to BPA.

Endocrine disrupting chemicals (EDCs) include bisphenols (BPA and its replacement  chemicals, such as BPF - used in products called "BPA free"), phthalates (especially used in vinyl products), parabens, chemicals used in flame retardants and non-stick coatings,  and some pesticides (e.g. the commonly used chlorpyrifos).

Especially worrisome is that while scientists typically test chemicals one at a time to determine their safety, in the real world we are all exposed to mixtures of these chemicals in our food, consumer products (including personal care products and cosmetics), and environment. Some of these chemicals can cross the placenta during pregnancy and so have an effect on the developing the fetus, including brain and neurological development. Yes, some of these chemicals are only in the body for a short time, but during critical developmental  stages, the effects can be big - even at very low exposures.

Bottom line: If trying to conceive a child or during pregnancy, try to minimize exposure to plastics, pesticides, flame retardants, non-stick cookware, stain-proofing (in fabric and rugs), fragrances and scented products (including air fresheners and dryer sheets), and food stored in cans and plastic containers. Avoid triclosan, anti-odor, antibacterial, anti-germ products and clothing. Avoid parabens (in lotions, etc). Read labels. Glass and stainless steel is perfectly fine. Use unscented or fragrance free products as much as possible.

From Medical Xpress: Chemicals in consumer products during early pregnancy related to lower IQ   ...continue reading "Pregnancy, Endocrine Disrupting Chemicals, and Lower IQ"

Food is all important for health. A recent study (that analyzed data from 10 large studies in the US, Europe, and Asia) found an association between high fiber intake from foods and also frequent eating of yogurt with a lower incidence of lung cancer. Persons with the highest yogurt and fiber consumption had a 33% reduced risk of lung cancer (when compared to the group who did not consume yogurt and consumed the least amount of fiber).

Think of it this way: The fiber in foods feeds the beneficial bacteria in the gut. High fiber foods that feed microbes in the gut are known as prebiotics. It is good to eat a variety of foods, because they provide a variety of fibers. High fiber foods are whole grains, fruits, vegetables, seed, nuts, and legumes (beans).

Gut microbes use fiber to generate short-chain fatty acids, and these are anti-inflammatory. Evidence suggests that the beneficial effects are not restricted to the gut, but reach organs throughout the body, including the lungs. The researchers suggest that both fiber and yogurt have anti-inflammatory effects, and the combination of fiber and yogurt is stronger against lung cancer than either alone. They also thought that the Lactobacillus and Bifidobacterium species in yogurt somehow help improve the gut microbial system.

From Medical Xpress:  High fiber, yogurt diet associated with lower lung cancer risk  ...continue reading "High Fiber Foods, Yogurt, and Lung Cancer"

Reading the following study, I thought to myself - OK, once again someone is testing a supplement, but generally studies find that supplements don't do as well as real, actual foods in whatever is being tested. In this case, a supplement containing lycopene, which is found in tomatoes, was tested by researchers in the UK to see if it would help with sperm quality in men. Other studies have found dietary lycopene to have health benefits (e.g. lower incidence of lethal prostate cancer), which is among the reasons the researchers focused on testing it for semen quality.

The study design was nice - with 60 young healthy men randomly assigned to one of 2 groups - the supplement group and the placebo group, and no one knew who was assigned to which group (double blind). They took either the lycopene supplement (14 mg/d of lactolycopene, equivalent to 2 kg of cooked tomatoes)  or a placebo for 12 weeks. They found changes in sperm quality after the 12 weeks, with significant improvement in the proportion of "fast progressive sperm" and normally shaped sperm (morphology). However, "motile sperm concentration" (the number of moving sperm) did not improve - and this is considered the main measure associated with chance of conception. So it is unknown how the 2 things that improved would affect fertility.

Bottom line: Studies find numerous health benefits from diets rich in fruits and vegetables, including tomatoes and other red foods, such as watermelon, papaya, and pink grapefruit. And yes - ketchup is a good source. Apparently more lycopene is bioavailable when tomatoes are cooked or processed, especially when cooked in oil (as compared to raw tomatoes). And when eating fruits and vegetables, try to eat as many that are organically grown, because eating fruits and vegetables with high levels of pesticide residues has a negative effect on sperm quality.

From Science Daily: Dietary supplement from tomatoes discovered to boost sperm quality  ...continue reading "Lycopene In Tomatoes and Sperm Quality"

Bacterial vaginosis is a problem for many women, with estimates that up to a third of women of reproductive age get it at some point in life. Bacterial vaginosis is a condition where the microbes in the vagina are imbalanced or out-of-whack, especially with diminishing numbers and types of Lactobacillus species. Lactobacillus species are typically the dominant bacteria in healthy vaginal microbiomes.

Unfortunately, some women have recurring bacterial vaginosis (BV), many who wind up taking course after course of antibiotics to try to deal with it. Symptoms can include thin gray, white, or green vaginal discharge, vaginal itching, burning during urinbation, and a smelly fishy vaginal odor. Which is why a small study done in Israel finding success with vaginal microbial transplantation (VMT) from healthy donors to women with BV is very exciting.

Researchers transplanted vaginal fluid (with all its microbes) from 3 healthy women (and thus a healthy vaginal microbial community) into 5 women with severe BV that did not respond well to antibiotics. Afterwards four of the  recipients had long-lasting (up to 21 months) vaginal microbial changes and complete remission of BV (2 after the first transplant, 2 after 3 transplants) - becoming more like the donors' vaginal microbiome, and also rich in Lactobacillus. The 5th person had partial improvement of BV, but there were complications - she took a course of antibiotics for a throat infection, her BV symptoms returned, and then she received another vaginal microbiome transplant, after which her vaginal microbes were a mix of her original and the donors.

Of course larger studies are now needed, especially because there can be risks when receiving another person's microbes (e.g. accidental transfer of viruses). But I also want to point out that some of these Lactobacillus species (especially Lactobacillus crispatus) are easily available without a prescription, and women have been self-experimenting with them, many with good success.

Excerpts from Ars Technica - Vaginal-fluid transplants treat incurable condition in pilot study   ...continue reading "Vaginal Fluid Transplants Successfully Treat Bacterial Vaginosis"

Are statins overprescribed? Currently many people without heart disease and at low risk of heart disease are taking them as a preventive, what is known as "primary prevention". Over the years, changes in medical guidelines have resulted in more and more lower risk older healthy people being prescribed statins. But there has been controversy over this: Are the statins really preventing heart disease and deaths in these low risk people? Also, do the benefits outweigh the harms (because all medications have side-effects, some more serious than others)? Finally, are the extra financial costs worth it?

recent study published in the prestigious British Medical Journal (BMJ) suggests that statins may be overprescribed in many such lower risk cases.  But please, keep in mind that for people with heart disease, statins are uncontroversial, where there are clear benefits. The controversy is regarding statins for low risk people without heart disease.

For example, the study researchers point out that studies find that statin use can be associated with an increased risk of diabetes, various muscle problems, and hemorrhagic stroke, as well as some  milder side-effects. Yet, looking at just one country (Ireland), with the latest medical guidelines it would take about 400 lowest risk healthy people taking statins to prevent one major cardiovascular event. And the statins would be taken for years. Is it worth it? Also, the studies being published are those favorable to the pharmaceutical industry, while under reporting harms.

From Medical Xpress: For most healthy people, benefits of statins 'may be marginal at best'   ...continue reading "Are Statins Overprescribed?"

Very depressing news about football. A study looking at those who played football long-term (as a career in adulthood) found that for every year of playing tackle football (lots of pounding and repeated head collisions), a person's risk of developing chronic traumatic encephalopathy (CTE) increases by 30%. The researchers from the Boston Univ. School of Medicine arrived at this conclusion after looking at 266 deceased former amateur and professional football players.

What was different about this study was that they compared football players who did not develop CTE with those who did - so the researchers thought it was representative of career football players.

The study results make total sense, but are horrifying because of all the children in the US growing up and playing tackle football from a young age. Other studies find brain changes from just playing some semesters in high school or college or before the age of 12.

From Futurity: CTE RISK GOES UP 30% FOR EACH YEAR OF PLAYING FOOTBALL  ...continue reading "Football May Not Be A Good Career Choice"

Walking is important for health, but walking speed is also important. It turns out that slow walking speed or gait (particularly when trying to walk as fast as possible) is a problem sign already in mid-life (the 40s). Researchers found that slow walking speed is a sign of "accelerated aging",  and that slow walkers exhibited such signs as reduced brain volume, cortical thinning, and reduced brain surface area.

The Duke University researchers found that a slow walking speed at midlife was associated with poorer mental functioning, and that there was an average difference of 16 IQ points between the slowest and fastest walkers. The researchers point out that this matches other studies showing that there is an association of slow walking speed of older adults and cognitive impairment and risk of dementia. The researchers viewed midlife gait speed as a summary of life-long aging, and felt that some differences were apparent already at the age of three. [This was a 5 decade long study in New Zealand of 904 persons.]

From Medical Xpress: Slower walkers have older brains and bodies at 45

The walking speed of 45-year-olds, particularly their fastest walking speed without running, can be used as a marker of their aging brains and bodies ...continue reading "Are You A Slow Or Fast Walker?"