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A new report authored by dozens of scientists, health practitioners and children's health advocates is highlighting the (growing annually) evidence that many common and widely available chemicals endanger neurological development in fetuses and children of all ages. The chemicals contribute to such health problems as ADHD, autism spectrum disorders, lowered IQ, behavior disorders, and many other problems. Many of the chemicals have hormonal effects (endocrine disruptors) and interfere with normal hormonal activity. The chemicals of highest concern are all around us and are found in most pregnant women, their fetuses, and in growing children. In fact, in all of us.

Especially worrisome chemicals are:  leadmercury; organophosphate pesticides (used in agriculture and home gardens), phthalates (in medicines, plastics, and personal care products), flame retardants known as polybrominated diphenyl ethers (found in upholstered furniture, car seats), air pollutants produced by the combustion of wood and fossil fuels), and polychlorinated biphenyls (once used as coolants and lubricants in electrical equipment, but still pervasive). It is important to note that out of the thousands of chemicals that people are exposed to, that the great majority of chemicals are untested for neurodevelopmental effects.

Especially alarming is that the U.S. Centers for Disease Control found that 90% of pregnant women in the United States have detectable levels of 62 chemicals in their bodies, out of 163 chemicals for which the women were screened. This shows that we are exposed to mixtures of chemicals - not just to one chemical at a time.  Unfortunately the substitutes for problematic chemicals are NO better than the originals, because they tend to be similar chemically. For example, the substitutes for BPA are just as bad, if not worse, than BPA (bisphenol A). And remember, we are exposed to mixtures of chemicals - not just to one chemical at a time.

The report criticizes current regulatory lapses that allow chemicals to be introduced into people's lives with little or no review of their effects on fetal and child health. "For most chemicals, we have no idea what they're doing to children's neurodevelopment," Professor Schantz (one of the signers of the report) said. "They just haven't been studied." So why aren't policymakers doing something? Why is industry dictating what we're exposed to? Why are chemicals innocent until proven guilty, and even then they're allowed to be used? Who is looking out for the ordinary person, and especially developing children?

From the journal Environmental Health Perspectives: Project TENDR: Targeting Environmental Neuro-Developmental Risks. The TENDR Consensus Statement

Children in America today are at an unacceptably high risk of developing neurodevelopmental disorders that affect the brain and nervous system including autism, attention deficit hyperactivity disorder, intellectual disabilities, and other learning and behavioral disabilities. These are complex disorders with multiple causes—genetic, social, and environmental. The contribution of toxic chemicals to these disorders can be prevented. 

Leading scientific and medical experts, along with children’s health advocates, came together in 2015 under the auspices of Project TENDR: Targeting Environmental Neuro-Developmental Risks to issue a call to action to reduce widespread exposures to chemicals that interfere with fetal and children’s brain development. Based on the available scientific evidence, the TENDR authors have identified prime examples of toxic chemicals and pollutants that increase children’s risks for neurodevelopmental disorders. These include chemicals that are used extensively in consumer products and that have become widespread in the environment. Some are chemicals to which children and pregnant women are regularly exposed, and they are detected in the bodies of virtually all Americans in national surveys conducted by the U.S. Centers for Disease Control and Prevention. The vast majority of chemicals in industrial and consumer products undergo almost no testing for developmental neurotoxicity or other health effects.

Based on these findings, we assert that the current system in the United States for evaluating scientific evidence and making health-based decisions about environmental chemicals is fundamentally broken. To help reduce the unacceptably high prevalence of neurodevelopmental disorders in our children, we must eliminate or significantly reduce exposures to chemicals that contribute to these conditions. We must adopt a new framework for assessing chemicals that have the potential to disrupt brain development and prevent the use of those that may pose a risk. This consensus statement lays the foundation for developing recommendations to monitor, assess, and reduce exposures to neurotoxic chemicals. 

The TENDR Consensus Statement is a call to action to reduce exposures to toxic chemicals that can contribute to the prevalence of neurodevelopmental disabilities in America’s children. The TENDR authors agree that widespread exposures to toxic chemicals in our air, water, food, soil, and consumer products can increase the risks for cognitive, behavioral, or social impairment, as well as specific neurodevelopmental disorders such as autism and attention deficit hyperactivity disorder (ADHD) (Di Renzo et al. 2015; Gore et al. 2015; Lanphear 2015; Council on Environmental Health 2011). This preventable threat results from a failure of our industrial and consumer markets and regulatory systems to protect the developing brain from toxic chemicals. To lower children’s risks for developing neurodevelopmental disorders, policies and actions are urgently needed to eliminate or significantly reduce exposures to these chemicals.

We are witnessing an alarming increase in learning and behavioral problems in children. Parents report that 1 in 6 children in the United States, 17% more than a decade ago, have a developmental disability, including learning disabilities, ADHD, autism, and other developmental delays (Boyle et al. 2011). As of 2012, 1 in 10 (> 5.9 million) children in the United States are estimated to have ADHD (Bloom et al. 2013). As of 2014, 1 in 68 children in the United States has an autism spectrum disorder (based on 2010 reporting data) (CDC 2014).

Many toxic chemicals can interfere with healthy brain development, some at extremely low levels of exposure. Research in the neurosciences has identified “critical windows of vulnerability” during embryonic and fetal development, infancy, early childhood and adolescence (Lanphear 2015; Lyall et al. 2014; Rice and Barone 2000). During these windows of development, toxic chemical exposures may cause lasting harm to the brain that interferes with a child’s ability to reach his or her full potential.

The developing fetus is continuously exposed to a mixture of environmental chemicals (Mitro et al. 2015). A 2011 analysis of the U.S. Centers for Disease Control and Prevention’s (CDC) biomonitoring data found that 90% of pregnant women in the United States have detectable levels of 62 chemicals in their bodies, out of 163 chemicals for which the women were screened (Woodruff et al. 2011). Among the chemicals found in the vast majority of pregnant women are PBDEs, polycyclic aromatic hydrocarbons (PAHS), phthalates, perfluorinated compounds, polychlorinated biphenyls (PCBs), perchlorate, lead and mercury (Woodruff et al. 2011). Many of these chemicals can cross the placenta during pregnancy and are routinely detected in cord blood or other fetal tissues.

The following list provides prime examples of toxic chemicals that can contribute to learning, behavioral, or intellectual impairment, as well as specific neurodevelopmental disorders such as ADHD or autism spectrum disorder: Organophosphate (OP) pesticides, PBDE flame retardants, combustion-related air pollutants, which generally include PAHs, nitrogen dioxide and particulate matter, and other air pollutants for which nitrogen dioxide and particulate matter are markers, lead, mercuryPCBs .

The United States has restricted some of the production, use and environmental releases of these particular chemicals, but those measures have tended to be too little and too late. We face a crisis from both legacy and ongoing exposures to toxic chemicals.....The examples of developmental neurotoxic chemicals that we list here likely represent the tip of the iceberg....Only a minority of chemicals has been evaluated for neurotoxic effects in adults. Even fewer have been evaluated for potential effects on brain development in children (Grandjean and Landrigan 2006, 2014). Further, toxicological studies and regulatory evaluation seldom address combined effects of chemical mixtures, despite evidence that all people are exposed to dozens of chemicals at any given time.

Some chemicals, like those that disrupt the endocrine system, present a concern because they interfere with the activity of endogenous hormones that are essential for healthy brain development. Endocrine-disrupting chemicals (EDCs) include many pesticides, flame retardants, fuels, and plasticizers. One class of EDCs that is ubiquitous in consumer products are the phthalates. These are an emerging concern for interference with brain development and therefore demand attention.

Under our current system, when a toxic chemical or category of chemicals is finally removed from the market, chemical manufacturers often substitute similar chemicals that may pose similar concerns or be virtually untested for toxicity. This practice can result in “regrettable substitution” whereby the cycle of exposures and adverse effects starts all over again. The following list provides examples of this cycle: When the federal government banned some uses of OP pesticides, manufacturers responded by expanding the use of neonicotinoid and pyrethroid pesticides. Evidence is emerging that these widely used classes of pesticides pose a threat to the developing brain (Kara et al. 2015; Richardson et al. 2015; Shelton et al. 2014). 

When the U.S. Government reached a voluntary agreement with flame retardant manufacturers to stop making PBDEs, the manufacturers substituted other halogenated and organophosphate flame retardant chemicals. Many of these replacement flame retardants are similar in structure to other neurotoxic chemicals but have not undergone adequate assessment of their effects on developing brains. When the federal government banned some phthalates in children’s products, the chemical industry responded by replacing the banned chemicals with structurally similar new phthalates. These replacements are now under investigation for disrupting the endocrine system.

 Two interesting studies about vitamins during pregnancy and possible effects on the child. One found that low levels of vitamin D3 is linked to behavioral issues and ADHD symptoms in preschool aged children, while the other raises the possibility of very high levels of folic acid during pregnancy linked to autism in the child. More studies are needed.

From Medscape:  Maternal Vitamin D Deficiency and Behavioral Issues in Offspring

Maternal vitamin D deficiency in early pregnancy is associated with an increased risk of behavioral issues and attention-deficit/hyperactivity disorder (ADHD)–like symptoms in preschool children, according to new data from a birth cohort study in Greece. But no association was found between maternal vitamin D deficiency and cognitive scores in the children at age 4, reported Vasiliki Daraki, MD, an endocrinologist from the University of Crete, Heraklion, Greece, who led the analysis, which was  a poster presented at the European Congress of Endocrinology 2016.

The analysis showed that maternal vitamin D levels lower than 50 nmol/L during the first trimester of pregnancy were associated with increased behavioral problems and ADHD-like symptoms among the offspring...."The lower the mother's vitamin D levels, the higher the child's hyperactivity and inattention," reported Dr Daraki.

"I think the role of vitamin D in the developing brain is in neuronal differentiation and axon development, and these are more important for behavioral problems than for cognition," Dr Daraki added.....In the future, she and her colleagues intend to measure the cognitive function and behavioral status at the age of 7 years and determine whether the results still hold at the later age.

From Medical Xpress:  A study asks: Too much folic acid a cause of autism?

For decades, pregnant women and women who may become pregnant have been advised to take folic acid to help prevent certain birth defects. But a new study suggests it may be possible to get too much of a good thing—very high levels of the vitamin in mothers' blood at the time of childbirth was linked to higher risk of their children developing autism years later. (Other research points to an opposite relationship between folic acid and autism, showing that adequate amounts of the vitamin at the time of conception can significantly reduce the risk.) 

Folate is a vitamin found in foods that is important in cell growth and development of the nervous system. A synthetic version, folic acid, is used in supplements and is used to fortify flour and cereals. Decades ago, researchers found certain levels of folic acid could prevent major birth defects of the baby's brain and spine. In the early 1990s, U.S. health officials began recommending that all women who might become pregnant should take 400 micrograms of folic acid daily. And in the late 1990s, federal regulations began mandating that folic acid be added to flour, bread and other grain products.

The new researchers followed 1,391 children who were born at Boston University Medical Center in 1998 through 2013. About 100 of them were later diagnosed with an autism spectrum disorder. The researchers went back and looked at levels of folate and vitamin B12 in the blood of the children's mothers at the time of childbirth. They found that 16 of them had very high levels of folate, and 15 had extremely high levels of vitamin B12. If both levels are extremely high, there is more than a 17-fold greater risk that a child will develop autism, the researchers said. 

Most of the moms in the study said they took multivitamins—which would include folic acid and vitamin B12—throughout their pregnancy. But the researchers say they don't know why some women had such high levels in their blood. It may be related to taking too many supplements and eating too many fortified foods. Or there could be a genetic reason that caused some women to absorb more folate than others. Or there could be a combination, they said.

A recent study found that school age children with higher levels of BPA in their bodies were more likely to have an ADHD (Attention Deficit Hyperactivity Disorder)  diagnosis. BPA or Bisphenol A is everywhere (in plastics, linings of cans, etc), found in varying levels in almost everyone, but at least it is eliminated fairly rapidly from the body. So trying to avoid BPA (e.g., buying and storing food in glass containers rather than cans or plastic containers) can quickly lower levels in the body. From Environmental Health News:

Hyperactivity in children linked to plastic additive, BPA

Children in the U.S. with higher levels of BPA in their bodies were more likely to have Attention-Deficit/Hyperactivity Disorder (ADHD), according to a study. The study of 460 children across the U.S. aged 8 to 15 years old found that 11 percent of those with BPA levels higher than the median level had ADHD. In contrast, 3 percent of those children with BPA levels below the median had ADHD. The research, published online last week in the Environment Research journal, adds to evidence that children’s BPA exposure may alter brain development and lead to behavior problems such as reduced attention and hyperactivity. 

The association was stronger for boys than girls, which reflects broader ADHD rates. Nationally about 10 percent of children between 5 and 17 have had an ADHD diagnoses, with boys having a much higher rate at 14 percent. By comparison about 6 percent of girls have the disorder, according to the U.S. Centers for Disease Control and Prevention.....BPA mimics estrogen hormones.The sexes use hormones differently to influence brain function.

BPA—used to make plastic hard and shatterproof and to extend the shelf life of canned food—can leach out of can linings and into the food. Studies show that just about everyone has traces of the chemical in their body—for instance, 97 percent of the children in this study had BPA in their urine. The additive has been linked to multiple health impacts in exposed babies and children—including obesity, asthma, low birth weights and genital defects.

A 2014 study on prenatal exposure to BPA found higher levels meant more behavior problems for school-age boys. Evans, lead author of that study, said prenatal exposure to chemicals is a “window of high susceptibility,” but so are the childhood years. The brain keeps developing into the 20s. Research specifically looking at ADHD and BPA exposure has been mixed, with some finding a link and some not. Most of the previous studies, however, have been on children younger than 8 years old, and ADHD and its symptoms are often realized later than that.

Animal studies show that BPA may alter the body’s dopamine—a chemical messenger that helps people think and stay alert and focused. “Dopamine systems are modulated by estrogen and BPA is a synthetic estrogen,” Froehlich said. There are also suggestions that BPA can interact with thyroid hormones—“critical in normal brain development,” Evans said.

That a male's preconception behaviors and exposure to all sorts of environmental contaminants (alcohol, drugs, medicines, chemicals at work, pesticides, etc) has effects on sperm and is linked to birth defects has been known for decades. What is new is the focus on epigenetics, or as some researchers call it: inherited paternal epigenetics. Three different paternal influences that affect the fetus and child (thus paternal experiences influence what the child inherits) are discussed in a review article: paternal age, environmental factors, and alcohol consumption.The researchers also found that environmental effects during the lifetime of a father can affect not only his immediate offspring, but also future generations.

What is epigenetics? Researchers in the study summarized it as: "Epigenetics are heritable alterations in gene expression that do not involve changes in the germline DNA sequence. It works primarily through three mechanisms: DNA methylation, histone modification, and microRNA (miRNA) expression."

Huh? This means that in epigenetics, the DNA doesn't change, but external or environmental factors switch genes on and off and affect how cells read genes. In other words, it's how the environment can alter gene expression without changing the genetic code. Epigenetic change is a regular and natural occurrence, but can also be influenced by several factors: age, the environment/lifestyle (such as diet, alcohol consumption, and chemical exposure), and disease state.  For example, what you eat and how much you drink (alcohol), where you live, what chemicals you're exposed to, how you exercise, even aging – all of these can eventually cause chemical modifications around the genes that will turn those genes on or off over time. Additionally, in certain diseases such as cancer or Alzheimer’s, various genes will be switched into the opposite state, away from the normal/healthy state. From Science Daily:

Fathers' age, lifestyle associated with birth defects

A growing body of research is revealing associations between birth defects and a father's age, alcohol use and environmental factors, say researchers at Georgetown University Medical Center. They say these defects result from epigenetic alterations that can potentially affect multiple generations. The study, published in the American Journal of Stem Cells, suggest both parents contribute to the health status of their offspring -- a common sense conclusion which science is only now beginning to demonstrate, says the study's senior investigator, Joanna Kitlinska, PhD, an associate professor in biochemistry, and molecular and cellular biology.

"We know the nutritional, hormonal and psychological environment provided by the mother permanently alters organ structure, cellular response and gene expression in her offspring," she says. "But our study shows the same thing to be true with fathers -- his lifestyle, and how old he is, can be reflected in molecules that control gene function," she says. "In this way, a father can affect not only his immediate offspring, but future generations as well."

For example, a newborn can be diagnosed with fetal alcohol spectrum disorder (FASD), even though the mother has never consumed alcohol, Kitlinska says. "Up to 75 percent of children with FASD have biological fathers who are alcoholics, suggesting that preconceptual paternal alcohol consumption negatively impacts their offspring."

The report is a review of evidence, human and animal, published to date on the link between fathers and heritable epigenetic programming. Among the studies reviewed are ones that find: - Advanced age of a father is correlated with elevated rates of schizophrenia, autism, and birth defects in his children; - A limited diet during a father's pre-adolescence has been linked to reduced risk of cardiovascular death in his children and grandchildren; - Paternal obesity is linked to enlarged fat cells, changes in metabolic regulation, diabetes, obesity and development of brain cancer; - Psychosocial stress on the father is linked to defective behavioral traits in his offspring; and - Paternal alcohol use leads to decreased newborn birth weight, marked reduction in overall brain size and impaired cognitive function.

More evidence linking endocrine disrupting chemicals such as butyl paraben, triclocarbon, propyl paraben. with negative health effects (here linked to effects on the pregnancy and baby). It is especially important to try to lower exposure to endocrine disruptors during pregnancy. So read labels on all personal care products and avoid all parabens, phthalates, triclocarban, bisphenol-A (BPA), and triclosan - because what you use on your body will get into your body, From Medical Xpress:

Use of personal care products during pregnancy linked to adverse effects in newborns

A study led by SUNY Downstate Medical Center's School of Public Health presents evidence linking personal care products used during pregnancy to adverse reproductive effects in newborns."The study found a link between women with higher levels of butyl paraben, which is commonly used as a preservative in cosmetics, and the following birth outcomes: shorter gestational age at birth, decreased birth weight, and increased odds of preterm birth," says Laura Geer, PhD, MHS, associate professor in the Department of Environmental and Occupational Health Sciences in the School of Public Health at SUNY Downstate.

The antimicrobial compound, triclocarban, mainly added to soaps, was associated with shorter gestational age at birth. Another common chemical added to lotions and creams, propyl paraben, was associated with decreased body length at birth. The long-term consequences of this are not clear, and, Geer adds, "Findings must be reproduced in larger studies."

Dr. Geer says, "Our latest study adds to the growing body of evidence showing that endocrine-disrupting compounds can lead to developmental and reproductive problems in animals and in humans. Effects observed in previous studies mainly came from animal models only." This study presents evidence of potentially adverse impacts in humans. 

Regulations requiring removal of triclosan from various consumer care products have been in place since 2015 in the European Union, but broader regulatory action by the U.S. Food and Drug Administration and the U.S. Environmental Protection Agency has not ensued.

More on this same story from Environmental Health News:  Soap, makeup additives linked to preterm births, smaller babies

Pregnant women in Brooklyn with high levels of certain compounds used in makeup and soaps were more likely to have preterm births and babies that weighed less, according to a new study. The study, published online last week in the Journal of Hazardous Materials, provides the first evidence that germ-killing and preservative chemicals used in cosmetics and soaps might impact newborns’ health. It also bolsters suspicions that chemicals in soaps and lotions disrupt people’s endocrine systems, which are crucial for reproduction and babies’ development.

From 2007 to 2009, Geer and colleagues tested 185 mothers’ third trimester urine, as well as the umbilical cord blood of 34 of them, for a suite of different parabens, used mostly in cosmetics, and triclosan and triclocarban, which are used as antimicrobials in soaps. The mothers were from the University Hospital of Brooklyn’s Prenatal Clinic.

The chemicals, especially the parabens, are common: According to the Environmental Working Group’s Skin Deep database, butylparaben is used in 2,245 personal care products, propylparaben is used in 7,212, and triclocarban is used in 21.

The results don’t prove that the chemicals are behind the birth problems. While scientists know the chemicals have some biological activity, the amount of exposure that could cause problems remains unclear.  Animals exposed to the chemicals have had some reproductive impacts. In rats, triclocarban impacted male sex organ development in a 2008 studyParaben exposure decreased male rat sperm counts and efficiency in a 2002 study. One of the most studied endocrine disrupting chemicals, bisphenol-A or BPA, has been linked to multiple birth defects....Except for some color additives, the U.S. Food and Drug Administration does not regulate cosmetic ingredients.

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This is so sad. Preschoolers should not be labeled as ADHD and drugged, but instead behavioral methods to deal with the child's behaviors should be used. They absolutely work. But...it takes effort and commitment on the part of the parents.

Just filling a prescription is soooo much easier. But all medicines have side-effects (and the side-effects are serious). These are young developing children (with developing brains) that are put on strong medicines for years. Currently we do not have a good understanding of long-term effects of these ADHD drugs when given at such a young age and continued for years.

The Centers for Disease Control and Prevention is disturbed by the finding that 3 out of 4 very young children with an ADHD diagnosis are given medications and says behavior therapy is the recommended first-line treatment. Specifically: "Behavior therapy is an effective treatment that improves ADHD symptoms without the side effects of medicine."

And by the way, basically all children 2 and 3 years old (and older) exhibit behaviors that some can label as ADHD. No matter how one looks at it, the diagnosis is used too much in young children, behavioral methods to deal with problem behaviors are underused, and medicines are overused.

From Medical Xpress: CDC: Preschoolers with ADHD often given drugs before therapy

Too many preschoolers with ADHD still are being put on drugs right away, before behavior therapy is tried, health officials say. The Centers for Disease Control and Prevention reported Tuesday that three in four young kids diagnosed with attention deficit hyperactivity disorder are put on medicines. New CDC data shows that's continued, even after research found behavior therapy is as effective and doesn't give children stomach aches, sleep problems or other drug side effects. 

Why? Health insurance coverage for behavior therapy may vary from state to state and company to company. And in some areas, therapists are in short supply, some experts said. On Tuesday, CDC officials doubled down on its previous recommendations, calling on doctors and families to try behavior therapy first.

ADHD makes it hard for kids to pay attention and control impulsive behavior. More than 6 million U.S. children have been diagnosed with it. "By the time a parent comes to meet with me, they are tired and worried," Dr. Georgina Peacock, a CDC developmental pediatrician who works with ADHD families. "They are concerned their child might jump down a flight of stairs, that the child could get lost in a grocery store, or that the child could be kicked out of preschool."

There's no blood test for ADHD. Diagnosis is a matter of expert opinion. Studies have shown medications like ritalin help older children with ADHD. That success has fed a trend to treat younger kids the same way, but there's been less study of how effective and safe the drugs are for preschoolers. In behavior therapy, a therapist trains parents—commonly over eight or more sessions—how to guide a child's behavior through praise, communication, routine and consistent discipline. However, it can take longer and demand more of parents.

In its new analysis, the CDC looked at insurance claims data for children ages 2 to 5. ....The CDC found 75 percent of the children were on medicine. That was true both of Medicaid-covered children in low-income families, and kids covered by private insurance. In contrast, only around half of children had received psychological services that might include behavior therapy training, the CDC found.

Study after study finds negative effects on the brain from playing football - here it is one season of high school football resulting in measurable brain changes. None of these players had a concussion during the season, and so the negative effects were from subconcussive head impacts or hits. Interestingly, those special helmets they wore to measure impacts showed no relationship with what the brain scans showed - so the helmets were basically useless in measuring subconcussive impacts. From Science Daily:

Head impacts from single season of high school football produce measurable change in brain cells

Repeated impacts to the heads of high school football players cause measurable changes in their brains, even when no concussion occurs, according to new research. Researchers gathered data from high school varsity players who donned specially outfitted helmets that recorded data on each head impact during practice and regular games. They then used experimental techniques to measure changes in cellular microstructure in the brains of the players before, during, and after the season.

"Our findings add to a growing body of literature demonstrating that a single season of contact sports can result in brain changes regardless of clinical findings or concussion diagnosis," said senior author Dr. Joseph Maldjian, Chief of the Neuroradiology Division and Director of the Advanced Neuroscience Imaging Research Lab, part of the Peter O'Donnell Jr. Brain Institute at UT Southwestern.

In the study, appearing in the Journal of Neurotrauma, a team of investigators at UT Southwestern, Wake Forest University Medical Center, and Children's National Medical Center evaluated about two dozen players over the course of a single football season.....During the pre-season each player had an MRI scan and participated in cognitive testing, which included memory and reaction time tests. During the season they wore sensors in their helmets that detected each impact they received. Post-season, each player had another MRI scan and another round of cognitive tests. 

Researchers then used diffusional kurtosis imaging (DKI), which measures water diffusion in biological cells, to identify changes in neural tissues. ....DKI also allowed the researchers to measure white matter abnormalities. White matter consists of fibers that connect brain cells and can speed or slow signaling between nerve cells. In order for the brain to reorganize connections, white matter must be intact and the degree of white matter damage may be one factor that limits the ability of the brain to reorganize connections following TBI.

Football has the highest concussion rate of any competitive contact sport, and there is growing concern -- reflected in the recent decrease in participation in the Pop Warner youth football program -- among parents, coaches, and physicians of youth athletes about the effects of subconcussive head impacts, those not directly resulting in a concussion diagnosis, researchers noted. Previous research has focused primarily on college football players, but recent studies have shown impact distributions for youth and high school players to be similar to those seen at the college level, with differences primarily in the highest impact magnitudes and total number of impacts, the researchers noted.

 A number of recent studies looked at vitamin D and various diseases. All showed benefits of higher vitamin D levels in the blood: lower rates of cancer incidence, improved heart function in those with heart failure, lower rates of leukemia incidence, lower rates of breast cancer, and less aggressive breast and prostate cancer. However, one study found no benefits to vitamin D supplementation during pregnancy and the child's asthma risk. Older studies found low levels of vitamin D linked to higher risk of premenopausal breast cancer, and also to thicker melanomas at diagnosis (the thinner the melanoma, the better the prognosis).

Everyone agrees that sunshine is an excellent source of vitamin D, but there is still disagreement over what are the best daily vitamin D supplement dosages, or even what are optimal levels of vitamin D in the blood (measured as serum 25-hydroxyvitamin D or 25(OH)D). In 2010, the Institute of Medicine (IOM) concluded that levels lower than 12 ng/ml represented a vitamin D deficiency and recommended a target of 20 ng/ml, which could be met in most healthy adults (ages 19 to 70) with 600 International Units of vitamin D each day. Since then most researchers have argued for higher blood serum levels: most agreeing that over 30 ng/ml is best, while some advocating 50 ng/ml or more. But even what's too high (and could cause problems) is debated. Many vitamin D supporters now advocate taking 800 to 1,000 IUs of vitamin D daily (some say up to 4000 IUs daily is OK). Remember to look for vitamin D3 supplements, not D2.

This study found that higher levels of vitamin D (measured as serum 25(OH)D) are better, with 25(OH)D concentrations of at least 40 ng/ml best to reduce cancer risk (all types of cancer). From Medical Xpress: Higher levels of vitamin D correspond to lower cancer risk, researchers say

Researchers at University of California, San Diego School of Medicine report that higher levels of vitamin D - specifically serum 25-hydroxyvitamin D - are associated with a correspondingly reduced risk of cancer. The findings are published in the April 6, online issue of PLOS ONE.

Garland and his late brother, Frank, made the first connection between vitamin D deficiency and some cancers in 1980 when they noted populations at higher latitudes (with less available sunlight) were more likely to be deficient in vitamin D, which is produced by the body through exposure to sunshine, and experience higher rates of colon cancer. Subsequent studies by the Garlands and others found vitamin D links to other cancers, such as breast, lung and bladder.

The new PLOS ONE study sought to determine what blood level of vitamin D was required to effectively reduce cancer risk....The only accurate measure of vitamin D levels in a person is a blood test....Cancer incidence declined with increased 25(OH)D. Women with 25(OH)D concentrations of 40 ng/ml or greater had a 67 percent lower risk of cancer than women with levels of 20 ng/ml or less.

Garland does not identify a singular, optimum daily intake of vitamin D or the manner of intake, which may be sunlight exposure, diet and/or supplementation. He said the current study simply clarifies that reduced cancer risk becomes measurable at 40 ng/ml, with additional benefit at higher levels. "These findings support an inverse association between 25(OH)D and risk of cancer," he said, "and highlight the importance for cancer prevention of achieving a vitamin D blood serum concentration above 20 ng/ml, the concentration recommended by the IOM for bone health."

From Science Daily: Vitamin D improves heart function, study finds

A daily dose of vitamin D3 improves heart function in people with chronic heart failure, a five-year research project has found. The study involved more than 160 patients who were already being treated for their heart failure using proven treatments including beta-blockers, ACE-inhibitors and pacemakers.

Participants were asked to take vitamin D3 or a dummy (placebo) tablet for one year. Those patients who took vitamin D3 experienced an improvement in heart function which was not seen in those who took a placebo....In the 80 patients who took Vitamin D3, the heart's pumping function improved from 26% to 34%. In the others, who took placebo, there was no change in cardiac function.

Disappointing results. From Medscape: Vitamin D Disappoints: Prenatal Supplementation and Childhood Asthma

Two recent clinical trials examined maternal supplementation with vitamin D and postpregnancy offspring outcomes for asthma and wheezing....However, with respect to preventing asthma in offspring, there is no clear evidence for vitamin D supplementation in pregnant women.

From PLOS ONE: Vitamin D Deficiency at Melanoma Diagnosis Is Associated with Higher Breslow Thickness

Vitamin D deficiency at the time of melanoma diagnosis is associated with thicker tumours that are likely to have a poorer prognosis. Ensuring vitamin D levels of 50 nmol/L or higher in this population could potentially result in 18% of melanomas having Breslow thickness of <0.75 mm rather than ≥0.75 mm.

Reported in 2013. From Medical Express: Low vitamin D levels linked to high risk of premenopausal breast cancer

A prospective study led by researchers from the University of California, San Diego School of Medicine has found that low serum vitamin D levels in the months preceding diagnosis may predict a high risk of premenopausal breast cancer. The study of blood levels of 1,200 healthy women found that women whose serum vitamin D level was low during the three-month period just before diagnosis had approximately three times the risk of breast cancer as women in the highest vitamin D group. 

A 2011 meta-analysis by Garland and colleagues estimated that a serum level of 50 ng/ml is associated with 50 percent lower risk of breast cancer. While there are some variations in absorption, those who consume 4000 IU per day of vitamin D from food or a supplement normally would reach a serum level of 50 ng/ml.

In the last few years some people have raised the issue of whether subconcussions in chidren, teenagers, and adults playing football also leads to brain changes similar to concussions. Subconcussions are head impacts that aren't as strong as concussions, but they routinely happen to players in football games and practice. Research says YES - worrying brain changes are occurring from subconcussions, but long-term effects from them are currently unknown. Earlier research found that the brains of high school football players (who had only received head impacts during the season) don't fully heal during the off-season when football is not played. (More related posts on subconcussions: high school players, football before age 12, teen football players, soccer players). The research discussed below is ongoing research. From Medical Xpress:

Subconcussions cause changes to brain, study of college football players shows

The average college football player receives about 1,000 head impacts each season. Some of these hits result in concussions – traumatic head injury that results in short-term, and possibly even long-term, damage to brain function. But what are the effects of the hundreds of routine head impacts, called subconcussions, that occur during a four-month season of practice sessions and games?

A University of Virginia neuroscience Ph.D. candidate is trying to find out. Using functional magnetic resonance imaging – fMRI – Bryson Reynolds studied the brain activity and connectivity of a group of healthy college football players, before and after a competitive season, and compared the data to brain-activity scans of healthy male college soccer and lacrosse players, and to a control group of college male non-athletes.

He found that the football players experienced a disruption in "local functional connectivity" – the way different areas of the brain communicate with each other – while soccer and lacrosse players' brain activity did not noticeably change after a competitive season. The result for the soccer and lacrosse players was comparable to the control group, which also displayed no brain activity changes during a four-month period. "This is an important discovery regarding the football players because a similar disruption of local functional connectivity has also been found in athletes diagnosed with a concussion," Reynolds said.

"We have no ideas how these subconcussions might be affecting players' brains, but we are seeing concussion-like changes to the brain, at least in the short term," Reynolds said. "This does not necessarily mean that something bad is happening to the brain, but clearly some changes are occurring over the course of a season."

Neurologists know that concussions cause headaches, dizziness and sometimes loss of consciousness, and may also increase the risk for developing serious long-term neurodegenerative disorders, such as Alzheimer's disease, amyotrophic lateral sclerosis and chronic traumatic encephalopathy.

In other words, repeated head impacts over the course of a season, or perhaps a career, may be affecting the brain in ways not yet understood, but possibly similar to actual concussions. Reynolds' study did not include players who suffered concussions, and the subconcussions he observed were not causing perceptible problems or symptoms for the players. But the disruptions in brain activity recorded in the fMRI scans may indicate subtle changes that could be part of a larger picture. 

Some more bad news about BPA and other endocrine disruptors (hormone disruptors) such as the phthalate DEHP. Bottom line: Avoid plastics, BPA, BPS and other BPA substitutes (they're chemically similar and seem to have similar health effects) as much as possible. Most canned food has BPA or BPA substitutes in the can linings. Use glass and stainless steel to store food, microwave food in dishes (not in plastic containers or packages). Go to the Environmental Working Group site for more information on product information, what to avoid, and what to look for and get instead.

From Science daily: BPA substitute can trigger fat cell formation: Chemical used in BPA-free products exhibits similar endocrine-disrupting effects

Exposure to a substitute chemical often used to replace bisphenol A in plastics can encourage the formation of fat cells, according to a new study. The replacement chemical, bisphenol S, has a slightly different chemical structure than bisphenol A (BPA), a known endocrine disruptor. As of 2014, nearly 100 epidemiological studies have been published tying BPA to health problems, according to the Introductory Guide to Endocrine-disrupting Chemicals published by the Society and IPEN, a global network that supports sound chemicals management.

Concerns about BPA's health effects have encouraged some consumers to purchase food containers labeled "BPA-free." BPA-free products often contain bisphenol S (BPS)or other substitutes, but researchers have raised concerns that these replacements also interfere with the body's hormones and may pose similar threats to public health."Our research indicates BPS and BPA have comparable effects on fat cells and their metabolism," said the study's senior author, Ella Atlas, PhD, of Health Canada, the federal department responsible for helping Canadians maintain and improve their health. 

A report (a collaborative effort of 5 organizations) that looked for the presence of BPA and BPA substitutes in the linings of food cans from major food companies. And yes, they found BPA in most cans (67%). From the group Toxic Food Cans: Buyer Beware: Toxic BPA and regrettable substitutes found in the linings of canned food

This study set out to analyze the interior coatings and lids of nearly 200 canned foods collected in 19 states and one Canadian province to determine whether the use of bisphenol A (BPA) continues to be widespread among major national brands and retailers of canned foods. We also wanted to determine what replacement materials for BPA-based epoxy are being used by retailers and manufacturers and the extent to which those companies have studied the safety of those materials.

Our findings were alarming: This report validates our concerns that, despite consumer demand for BPA-free cans, 67 percent (129 of 192) of the cans we tested contained BPA-based epoxy in the body and/or the lid. Our investigation also found, for the first time, that some retailers and brands have replaced BPA with PVC, made from vinyl chloride, a carcinogen.

BPA is a hormonally active chemical. The scientific evidence linking BPA exposure to harm in humans is compelling and growing: More than 300 animal and human studies have linked exquisitely small amounts of BPA exposure, measured in parts per billion and even parts per trillion, to a staggering number of health problems, including breast and prostate cancer, asthma, obesity, behavioral changes (including attention deficit disorder), altered development of the brain and immune system, low birth weight and lowered sperm counts.

This study looked at plasticizers called phthalates (which are commonly found in medical tubes), and which also have endocrine disrupting effects. From Medical Xpress:  Attention deficit after kids' critical illness linked to plasticizers in medical tubes

Children who are often hospitalized in intensive care units are more likely to have attention deficit disorders later, and new research finds a possible culprit: a high level of plastic-softening chemicals called phthalates circulating in the blood. The researchers.....suggest these chemicals, which are added to indwelling medical devices such as plastic tubes and catheters, seep into the child's bloodstream.

"Phthalates have been banned from children's toys because of their potential toxic and hormone-disrupting effects, but they are still used to soften medical devices," said lead researcher Sören Verstraete, MD, a PhD student at KU (Katholieke Universiteit) Leuven in Leuven, Belgium. "We found a clear match between previously hospitalized children's long-term neurocognitive test results and their individual exposure to the phthalate DEHP during intensive care."

Di(2-ethylhexyl)phthalate, or DEHP, is the most commonly used plastic softener in medical devices made of polyvinyl chloride (PVC). Verstraete called the use of medical devices containing this phthalate "potentially harmful" for the brain development and function of critically ill children.