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For a few years I've been noticing that studies of vitamin D have had mixed results for a number of medical conditions. A number of times initial studies found an association with low levels of vitamin D and a number of medical conditions, but follow up well-designed studies are just not finding the same results with vitamin D supplementation - or results have been mixed. Also, in some studies, what initially looked like vitamin D being protective for some cancers and multiple sclerosis, now looks like it's sunlight that is giving the protective results. In some cases, vitamin D levels are a proxy for sunlight exposure (the more sunlight exposure, the higher the vitamin D levels in the person). The following 6 studies recently published highlight this same trend of mixed results.

While vitamin D levels increased from high dose vitamin D, there was no change in bone bone mineral density (BMD) in older adults during the 12 months of the study. No adverse effects form the vitamin D supplementation was reported [the older adults received 12,000 international units (IU), 24,000 IU, or 48,000 IU once a month]. From Science Daily: Vitamin D supplements are of no benefit to the over 70s

There is little benefit for those over 70 taking higher dose vitamin D supplements to improve their bone strength and reduce the risk of falls, new research has revealed.

High doses of vitamin D (4000 international units) appeared more beneficial than low dose vitamin D (400 international units) supplements in advanced colorectal cancer patients. From Medical Xpess: High-dose vitamin D shows benefit in patients with advanced colorectal cancer

...continue reading "Recent Vitamin D Studies Have Mixed Results"

Many of us have concerns over the fact that people are constantly exposed to endocrine disruptors (chemicals that disrupt hormonal systems) in many common household and personal products. Even the vinyl flooring found in many homes  contains phthalates, which are endocrine disrupting chemicals. In the past year several studies have looked at vinyl flooring in homes and whether the chemicals in the flooring outgas into the air and then get into people living in the homes. The answer is YES - the chemicals in vinyl flooring do get into people living there, and they can be measured in urine (in the breakdown products of phthalates called metabolites).

Since research shows that endocrine disrupting chemicals have health effects, then the question is: Do chronic low levels do anything to people? Especially worrisome is, are they having an effect on the developing fetus when pregnant women are exposed to them and they get into the body? The following 2 studies looked at flooring, but keep in mind that we are exposed to phthalates in many, many products - e.g., plastic shower curtains, plastic food containers, some personal care products, household products. The problem is that the pthalates migrate out of the plastic products - they don't stay in the product. In the case of vinyl flooring - one can say that there are phthalate emissions from the flooring! And of course it gets into household dust.

Numerous studies found that phthalates (the phthalate metabolites) are routinely found in people of all ages - throughout the world. It can be measured in our blood (serum) and in our urine. Studies find them in breastmilk and also in amniotic fluid. Research finds associations associations between exposure to several phthalates and various effects on human health, including reproductive effects.

The following are two complementary studies. Study 1 looked at vinyl flooring (called PVC flooring in the article) in homes (in the kitchen and bedrooms), and found that phthalates get into pregnant women, and can be measured in the urine. Study 2 (from Duke University), found that chemicals children are exposed to in the home from vinyl flooring and the sofa (flame-retardants) can be measured in their blood and urine. The researchers took all sorts of samples from homes and children over a 3 year period and found evidence in the children of exposure to phthalates, organophosphate esters, brominated flame retardants, parabens, phenols, antibacterial agents and perfluoroalkyl and polyfluoroalkyl substances (PFAS).

So we have proof that these chemicals are getting into us. We can't avoid them totally, but can lower our exposure levels - look for upholstered furniture without flame retardants (read the label!), and don't install vinyl flooring (wood and tile floors are OK).  ...continue reading "What’s Getting Into You From Vinyl Flooring?"

To the alarm of many, male fertility (sperm quality and sperm counts) has been rapidly declining over the past few decades. Researchers suspect that it's due to our exposure to chemicals in the environment, especially to endocrine disrupting chemicals - of which there are many, and to which we are exposed to daily. A recent study found that detrimental effects occur in the sperm of both humans and dogs when exposed to the common plastic softener DEHP and the persistent industrial chemical polychlorinated biphenyl 153 (PCB153). The researchers suggest this is because dogs live in households with humans and thus are exposed to the same environmental contaminants.

DEHP (diethylhexyl phthalate) is an endocrine disruptor (interferes with hormone systems) that is found in plastic materials in many household and personal items - for example, in carpets, vinyl flooring, some upholstery, rainwear, wires, some plastic toys, fragrances and air fresheners, some PVC pipes, some food packaging, medical tubing, plastic shower curtains. The problem is that it slowly leaches out of the products and into the air and household dust, it leaches out of packaging into foods (which we then ingest), and it can also be absorbed through direct skin contact. Bottom line: try to avoid DEHP by avoiding plastics known as polyvinyl chloride (PVC) or vinyl as much as possible. (One can't totally avoid them, but can reduce exposure to them.)

From Science Daily: Chemical pollutants in the home degrade fertility in both men and dogs, study finds

New research by scientists at the University of Nottingham suggests that environmental contaminants found in the home and diet have the same adverse effects on male fertility in both humans and in domestic dogs.  ...continue reading "Common Chemical Has Negative Effects On Sperm of Both Humans and Dogs"

Researchers have known for a while that human breast milk contains hundreds of species of bacteria that a baby ingests while feeding. This is good! The bacteria is seeding the baby's gut microbiome (microbial community). A recent study of breast milk from different continents found that breast milk from healthy mothers also contains species of fungi - which is the breast milk mycobiome. What was noteworthy was that some  types of fungi in breast milk were found among breast milk samples from all locations (a fungi "core group"), while other types of fungi varied among breast milk from the different locations and even how the baby was delivered (vaginal or C-section birth).

After analyzing the 80 samples of breast milk (20 from each country: Spain, Finland, South Africa, China) it was found that some fungi were the same in breast milk from the different locations: Malassezia, Davidiella, Sistotrema, and Penicillium, while others were different. Fungi from the genus Cryptococcus were higher in breast milk from women who delivered vaginally (as compared to those who had a C-section).  [Note: Genus ranks above species, but below family, and the written name is capitalized.]

This study confirms the importance of breast milk as a source of microbes (along with many nutrients and protective compounds) to the infant and infant gut. From Science Daily:

Breast milk microbiome contains yeast and fungi: Do these benefit the infant?  ...continue reading "It Is Normal For Fungi To Be In Breast Milk"

Today's topic: BIRTH. Two recent studies have results that question some current medical practices, which are when to cut the umbilical cord, and hospital vs home birth differences in the baby's gut microbes.

The first study makes a case against the current practice of cutting the umbilical cord immediately after birth. University of Rhode Island researchers found that delaying umbilical cord clamping for more than 5 minutes transfers iron rich blood from the placenta to the baby (resulting in about a 30% increase in blood volume). This resulted in babies at 4 months of age having higher iron storage (ferritin) levels and increased brain myelination. Myelin is a fatty material that wraps around nerve cell fibers - think of it as insulation of the brain's wiring.

The second study found that birth at home results in a more diverse microbiome (microbial community) in the baby at birth and one month later - when compared to babies born in hospitals. This study was conducted in the Hudson Valley region of NY state. All babies were born vaginally and were breastfed. Hospital born babies had decreased levels of some bacteria and increased levels of other bacteria (e.g. Clostridium - with other studies finding that higher levels in children is associated with an increased risk of asthma). It was suggested that certain hospital practices may be causing this (sterile drapes, antibiotics, etc.). 

From Medical Xpress: Study shows benefits of delayed cord clamping in healthy babies

A five-minute delay in the clamping of healthy infants' umbilical cords results in increased iron stores and brain myelin in areas important for early-life functional development, a new University of Rhode Island nursing study has found.  ...continue reading "Birth, Cord Clamping, and Some Microbial Differences"

The following is a really nice article about endocrine disruptors (chemicals that can interfere with the body's hormonal system). Journalist Hillary Brueck writes about where they are found (all around us!), some of the many negative health effects, and about NYU physician and researcher Dr. Leonardo Trasande and his new book: "Sicker, Fatter, Poorer: The Urgent Threat of Hormone-Disrupting Chemicals to Our Health and Future ... and What We Can Do About It." Also, some things we can do to lower our exposure to endocrine disruptors.

By the way, once again Europe is ahead of the US in dealing with this problem. Excerpts from Business Insider: A toxic-chemicals expert is sounding the alarm about 4 cancer-linked chemicals that could be making us sicker and fatter

Through the course of a single day, your hands, mouth, and body come in contact with countless pieces of paper, plastic, fabric, and furniture. You probably don't think about the chemicals these substances might harbor, or consider that they have a drug-like effect on health. But some do. They can make metabolisms slow down, subtly lower IQs, contribute to ADHD in children, and mess with sperm counts in men.

They're called "endocrine disruptors," and they're around us all the time. The chemicals change how our bodies work by shifting the way hormones operate, according to Leo Trasande, a pediatrician and public-health researcher at NYU Langone Health. "Hormones are the basic signaling molecules in our body that take on so many actions for practically every organ system," Trasande told Business Insider. "And endocrine disruptors are synthetic chemicals that scramble those signals, contributing to disease and disability."

In his new book, "Sicker, Fatter, Poorer: The Urgent Threat of Hormone-Disrupting Chemicals to Our Health and Future ... and What We Can Do About It," Trasande lays out the four big categories of endocrine disruptors he's most concerned about, based on evidence from scientific studies and observations in his patients. They are: Bisphenols, like BPA, which are often found in the linings of aluminum-canned food and drinks and on cash-register receipts. Brominated flame retardants that are in some carpets, furniture, and clothing. Synthetic pesticides on food. "Plasticizer chemicals" called phthalates that show up in plastic food packaging, lotions, and cosmetics.  ...continue reading "New Book Warning Us About Endocrine Disruptors"

Once again research finds that endocrine disruptors are associated with health effects - this time with earlier puberty in girlsEndocrine disruptors are chemicals that interfere with the body's endocrine (or hormone) systems and can produce all sorts of negative health effects, including all sorts of reproductive problems in both males and females. Phthalates, parabens, and phenols (all used in common everyday products) are examples of endocrine disruptors.

The researchers asked the question: Is a baby's exposure before birth or exposure around the time of puberty (peripuberty) to phthalates, parabens, and phenols (which are found in personal care products) associated with the timing of when he or she starts puberty? In other words, does the mother's exposure to these chemicals during pregnancy have an effect on the fetus, which then has an effect years later on the child's puberty? And how about peripubertal exposure? The answer is a strong YES for girls, and minimal effect on boys (but boys did have earlier genital development with propyl paraben exposure).

What is scary is that almost all women (and men) are exposed to these chemicals - which can be measured in the urine. Studies find these chemicals in over 96% of American women. What to do?  One can't totally escape these chemicals, but one can really minimize exposure by reading labels and avoiding personal care products that list phthalates, parabens, phenols, as well as Triclosan (found in some anti-bacterial soaps). Avoid products that include "fragrances" or "scents" (those have a multitude of chemicals in them, including endocrine disruptors). Avoid air fresheners, dryer sheets, scented candles, room deodorizers, essential oils (lavender, tea tree oil). Buy "unscented" or "fragrance free" products.

The good news is that once a person avoids these chemicals, the levels in the body go down. So it's worth the effort minimizing exposure to them. By the way, animal studies find numerous reproductive effects from these chemicals, including timing of puberty. From Medical Xpress:

Chemicals in personal care and household products linked to earlier puberty in girls

Chemicals that are widely used in personal care and household products are linked to girls entering puberty at earlier ages, according to findings from a long-running study of mothers and children published today. The study in Human Reproduction, one of the world's leading reproductive medicine journals, found that chemicals such as phthalates, parabens and phenols were all associated with earlier puberty in girls, although there was no similar association observed in boys.   

...continue reading "Personal Care Products and Puberty"

Pregnant women have been advised to keep their consumption of coffee and other caffeinated beverages (tea, sodas, cocoa, energy drinks), and chocolate containing foods to a minimum for decades. Currently the American College of Obstetrics recommends that women consume less than 200 mg of caffeine (from any source) per day during pregnancy. This is less than 2 cups of regular coffee  or 4 cups of regular black tea. But a recent  study's findings suggest that the levels should be kept much lower.

The study of 941 mother/baby pairs in Ireland found that each 100 mg increase of caffeine per day was associated with a lower birth weight, shorter length of pregnancy (gestational age), shorter birth length of the baby, and smaller head circumference of the baby at birth. The strongest associations between those who consumed the most caffeine (when compared to those who consumed the least) was with lower birth weight. The researchers think this occurs because caffeine crosses the placenta easily, but during pregnancy there is a slowed metabolism of caffeine (so it takes longer to get it out of the body). Similar results have been found in other recent studies. [On the other hand, for not pregnant women - coffee and tea are linked to all sorts of health benefits - here, here.]

From Medical Xpress: Caffeinated beverages during pregnancy linked to lower birth weight babies

...continue reading "Keep Caffeine To A Minimum During Pregnancy"

Can pesticides be detected in your home? A Cornell University study found that every single home they studied in different areas of upstate New York had detectable pesticide residues in the homes. Every single one of the 132 rural homes. Pesticides are colorless and odorless, but they still may be in your home from applications in the home or around the home from long ago. Pesticides can also be tracked in by your shoes or bare feet, on fur and clothing, or come in on the air (drift from pesticides being applied nearby), even off-gassing from soil. They stay in the dust in homes, and are absorbed by soft materials (such as rugs and upholstery, and even stuffed toys). Pesticides stay around so long (some even years) inside homes because they are not broken down easily (as they can be outdoors in the sun and rain).

The researchers pointed out that Americans use over 1 billion pounds of pesticides each year. Pesticides have health risks, even at low doses - for example, higher risks of various cancers, birth defects, neurological and immunological problems. Pregnant women (developing babies) and children are especially vulnerable to pesticide effects. For example, children are playing and crawling around on the floor sticking objects and their hands into the mouth. Pets also have health risks from pesticides, such as cancer.

While the pesticide residue samples in this study were taken in 2001 to 2002, the findings should apply today because pesticide use has risen tremendously since then - both on farms and elsewhere. And they tested for pesticides that are still commonly used today - such as 2.4-D (a commonly used herbicide, e.g. weed & feed for lawns, and on crops genetically modified to resist 2,4-D). The researchers didn't test for all the possible pesticides commonly used - just 15 of them. Unfortunately they didn't test for glyphosate , which is in Roundup, and heavily used nowadays - in crops and elsewhere as an herbicide (weed killer).

Think about it - at least in in the northeast, more people are using lawn pesticide services to get that "perfect, carpet-looking lawn" (really a monoculture that is environmentally horrible -  to bees and butterflies, soil organisms, birds, and anyone walking on it). How many people do you know get monthly or annual pesticide treatments in or around their homes "just in case"? In every instance  people are getting exposed to pesticides - breathing them in, getting them on their shoes, feet, clothing, bodies. Besides this study, other studies have also found pesticides in household and daycare center dust. How do studies measure pesticides in people? Typically by measuring their levels in blood and urine.

So what can one do to lower the amount and number of pesticides in the home? 1) First of all, don't use pesticides casually or routinely in your him. Use non-toxic alternatives instead - this is called least toxic IPM (Integrated Pest Management), which emphasizes monitoring the problem, looking for what causes the pest problem (moisture getting into the house, holes in the wall, etc.) and then treating the cause. It uses alternatives to "just spraying a pesticide" such as baits, traps, vacuuming of pests!, caulking where needed, fixing wet areas. It means thinking like a pest and what attracts the pest (the cause), and using the most non-toxic way possible to correct the problem. 2) Very important: take off shoes when entering your home. 3) Wipe up dust and vacuum frequently in the home. Other contaminants are also in the dust, such as lead and fire retardant chemicals. 4) Use organic approaches to gardening and taking care of your lawn. [Click on category PESTICIDES for all posts on pesticides, including their health effects. All 2,4-D posts. All pregnancy and pesticide posts.]

The study by Laquatra et al in JSM Health Education & Primary Health Care: Common Pesticide Residues in Rural Homes of New York State

Excerpts from Beyond Pesticides discussion of this study in its Daily News Blog: Study of New York State Homes Finds Pesticides In Every Sample Tested ...continue reading "Can Pesticides Be Detected In Your Home?"

The following article in a popular magazine follows up on research that came out last year about the alarming steep decline in male sperm counts and sperm concentration over the past few decades. This is true for the U.S., Europe, Australia, New Zealand, and it is thought world wide. The article discusses the causes: environmental chemicals and plastics, especially those that are endocrine disruptors (they disrupt a person's hormones!). These chemicals are all around us, and we all have some in our bodies (but the amounts and types vary from person to person). Some examples of such chemicals are parabens, phthalates, BPA and BPA substitutes.

Even though there are effects from these chemicals throughout life, some of the worst effects from these chemicals seem to be during pregnancy - with a big effect on the developing male fetus. Testosterone levels in men are also droppingBottom line: males are becoming "less male", especially due to their exposure to all these chemicals when they are developing before birth (fetal exposure). Since it is getting worse with every generation of males, the concern is that soon males may be unable to father children because their sperm count will be too low - infertility. Dogs are experiencing the same decline in fertility!

Why isn't there more concern over this? What can we do? We all use and need plastic products, but we need to use safer chemicals in products, ones that won't mimic hormones and have endocrine disrupting effects. Remember, these chemicals have more effects on humans than just sperm quality (here and here). While you can't totally avoid plastics and endocrine disrupting chemicals, you can definitely lower your exposure. And it's most important before conception (levels of these chemicals in both parents), during pregnancy, and during childhood.

Do go read the whole article. Excerpts from Daniel Noah Halpern's article in GQ: Sperm Count Zero

A strange thing has happened to men over the past few decades: We’ve become increasingly infertile, so much so that within a generation we may lose the ability to reproduce entirely. What’s causing this mysterious drop in sperm counts—and is there any way to reverse it before it’s too late? 

Last summer a group of researchers from Hebrew University and Mount Sinai medical school published a study showing that sperm counts in the U.S., Europe, Australia, and New Zealand have fallen by more than 50 percent over the past four decades. (They judged data from the rest of the world to be insufficient to draw conclusions from, but there are studies suggesting that the trend could be worldwide.) That is to say: We are producing half the sperm our grandfathers did. We are half as fertile.

The Hebrew University/Mount Sinai paper was a meta-analysis by a team of epidemiologists, clinicians, and researchers that culled data from 185 studies, which examined semen from almost 43,000 men. It showed that the human race is apparently on a trend line toward becoming unable to reproduce itself. Sperm counts went from 99 million sperm per milliliter of semen in 1973 to 47 million per milliliter in 2011, and the decline has been accelerating. Would 40 more years—or fewer—bring us all the way to zero? 

I called Shanna H. Swan, a reproductive epidemiologist at Mount Sinai and one of the lead authors of the study, to ask if there was any good news hiding behind those brutal numbers. Were we really at risk of extinction? She failed to comfort me. “The What Does It Mean question means extrapolating beyond your data,” Swan said, “which is always a tricky thing. But you can ask, ‘What does it take? When is a species in danger? When is a species threatened?’ And we are definitely on that path.” That path, in its darkest reaches, leads to no more naturally conceived babies and potentially to no babies at all—and the final generation of Homo sapiens will roam the earth knowing they will be the last of their kind.

...continue reading "Will All Men Eventually Be Infertile?"