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Can you have too high levels of vitamin D? The researchers themselves say that the results show there is a J shaped curve linking vitamin D levels in the blood and mortality - both too high and too low levels are linked to higher levels of mortality. From Science Daily:

High levels of vitamin D is suspected of increasing mortality rates

The level of vitamin D in our blood should neither be too high nor to low. Scientists have now shown that there is a connection between high levels of vitamin D and cardiovascular deaths.

In terms of public health, a lack of vitamin D has long been a focal point. Several studies have shown that too low levels can prove detrimental to our health. However, new research from the University of Copenhagen reveals, for the first time, that also too high levels of vitamin D in our blood is connected to an increased risk of dying from a stroke or a coronary.

"We have studied the level of vitamin D in 247,574 Danes, and so far, it constitutes the world's largest basis for this type of study. We have also analysed their mortality rate over a seven-year period after taking the initial blood sample, and in that time 16,645 patients had died. Furthermore, we have looked at the connection between their deaths and their levels of vitamin D," Professor at the Department of Clinical Medicine, Peter Schwarz explains.

The conclusion is clear: the study confirms that there is indeed a correlation between mortality rates and too low levels of vitamin D, but the new thing is that the level of vitamin D can also be too high.

"If your vitamin D level is below 50 or over 100 nanomol per litre, there is an greater connection to deaths. We have looked at what caused the death of patients, and when numbers are above 100, it appears that there is an increased risk of dying from a stroke or a coronary. In other words, levels of vitamin D should not be too low, but neither should they be too high. Levels should be somewhere in between 50 and 100 nanomol per litre, and our study indicates that 70 is the most preferable level," Peter Schwartz states.

This interesting study raises the possibility that eating certain foods or probiotics  (beneficial bacteria) may prevent diabetes. Note that Akkermansia is a bacteria with one species Akkermansia muciniphila . In Wikipedia:"Researchers have discovered that Akkermansia muciniphila may be able to be used to combat obesity and type 2 diabetes...The bacterium is naturally present in the human digestive tract at 3-5%, but has been seen to fall with obesity." Regarding Prevotella, in Wikipedia: "Studies also indicate that long-term diet is strongly associated with the gut microbiome composition—those who eat plenty of protein and animal fats typical of Western diet have predominantly Bacteroides bacteria, while for those who consume more carbohydrates, especially fiber, the Prevotella species dominate." From Science Daily:

Gut bacteria may contribute to diabetes in black males

African American men at elevated risk for developing type 2 diabetes may have fewer beneficial and more harmful intestinal bacteria, according to new research.

"The 'signature' of the gut microbiota -- the relative abundance of various bacteria and other microbes in the digestive system -- could be another useful tool in assessing a person's risk for developing diabetes," said Ciubotaru. Ciubotaru and her colleagues, including principal investigator Dr. Elena Barengolts,... found that a specific microbiota is associated with stable, normal blood glucose levels, while a different profile is associated with glucose levels that indicate pre-diabetes.

"The study provides additional reasons for physicians to recommend foods, such as prebiotics, which improve the growth and activity of helpful gut bacteria," said Barengolts. The gut microbiota helps digest food; fights infections; and plays an important role in keeping the immune system healthy. It is greatly influenced by genetics, diet and other environmental factors. Previous research has implicated an unhealthy or unbalanced microbiota as a contributing factor to metabolic disorders, including obesity and diabetes. The species that make up an individual's gut microbiota, as well as their abundance, can be identified by stool sample analysis.

The researchers determined the gut microbiotas of 116 African-American male veterans, age 45 to 75, participating in the D Vitamin Intervention in VA, or DIVA study. The aim of the DIVA study, which has 173 total participants and is funded by the Department of Veterans Affairs, is to determine if vitamin D supplementation can prevent diabetes in men with risk factors for developing the disease.

Participants were divided into four groups based on changes in their blood sugar levels as determined at the start and end of the one-year study. The groups included men whose glucose levels remained normal (non-pre-diabetic); those with stable levels indicative of pre-diabetes; those whose levels indicated a worsening of glucose control; and those whose levels improved. All the men provided stool samples for analysis of their gut microbiota.

Men whose blood sugar levels stayed normal over the year had more gut bacteria that are considered beneficial for metabolic health, whereas those who stayed pre-diabetic had fewer beneficial bacteria and more harmful bacteria. In addition, the group whose levels improved had more abundant Akkermansia--healthy bacteria--than the group that maintained normal blood sugar control throughout the year.

The study suggests that differences in the gut microbiota already exist in pre-diabetes, Barengolts said. Although the study found connections between composition of the gut microbiota and blood sugar control, Barengolts said further research is needed to confirm these findings and evaluate whether certain intestinal bacteria cause type 2 diabetes. However, based on other research her group has conducted and studies in animals, she speculated that the foods we eat affect our diabetes risk through our gut microbiota. If the mix of organisms in the intestinal tract is indeed responsible for the development of type 2 diabetes, she said, it may be possible to lower one's risk by changing the gut bacteria.

More details about that same study. From Medpage Today:

Prediabetes Patients Have Fewer Gut Bugs

They were put into one of four groups: those with a stable glucose tolerance, those with stable impaired fasting glucose or stable impaired glucose tolerance, those with worsened glucose tolerance, and those with improved glucose tolerance. There were significant differences in bacterial composition between the first and second groups (P=0.03) at the phylum level. Bacteroidetes was higher and Firmicutes was lower with worse glycemic control in the second group. 

Proteobacteria decreased over the period in groups 2 and 4 compared with group 1 (P=0.04 for both). At the family and genus levels, in group 2 versus group 1 there was less Prevotella, and a higher Bacteroides/Prevotella ratio in the second group at 5.6 to 2.7 (P=0.05). There was also less Enterobacteriaceae (P=0.03), and more Ruminococcae (P=0.01) and Veillonellaceae (P=0.02).

"We speculate that lower abundance of Prevotella may be associated with worsening glycemia, and, conversely, higher abundance of Akkermansia might be associated with improving glycemia, thus corroborating suggestions from previous studies," the researchers said.

What was really interesting in the recent study findings was not just that vegetarian diets are associated with an overall lower incidence of colorectal cancers, but that pescovegetarians (eat fish) had the lowest risk of all compared to nonvegetarians. That is really strong support for eating fish. From Science Daily:

Vegetarian diet linked to lower risk of colorectal cancers

Eating a vegetarian diet was associated with a lower risk of colorectal cancers compared with nonvegetarians in a study of Seventh-Day Adventist men and women, according to an article published online by JAMA Internal Medicine.

Colorectal cancer is the second leading cause of cancer death in the United States. Although great attention has been paid to screening, primary prevention through lowering risk factors remains an important objective. Dietary factors have been identified as a modifiable risk factor for colorectal cancer, including red meat which is linked to increased risk and food rich in dietary fiber which is linked to reduced risk, according to the study background.

Among 77,659 study participants, Michael J. Orlich, M.D., Ph.D., of Loma Linda University, California, and coauthors identified 380 cases of colon cancer and 110 cases of rectal cancer. Compared with nonvegetarians, vegetarians had a 22 percent lower risk for all colorectal cancers, 19 percent lower risk for colon cancer and 29 percent lower risk for rectal cancer. Compared with nonvegetarians, vegans had a 16 percent lower risk of colorectal cancer, 18 percent less for lacto-ovo (eat milk and eggs) vegetarians, 43 percent less in pescovegetarians (eat fish) and 8 percent less in semivegetarians, according to study results.

Research is accumulating that the microbial exposure from a vaginal birth, breastfeeding, and pets in the first year of life are all good for a baby's developing immune system and the gut microbiome.

From Science Daily: Breastfeeding, other factors help shape immune system early in life

Researchers say that breastfeeding and other factors influence a baby's immune system development and susceptibility to allergies and asthma by what's in their gut. The striking findings from a series of studies further advance the so-called hygiene hypothesis theory that early childhood exposure to microorganisms affects the immune system's development and onset of allergies, says Christine Cole Johnson, Ph.D., MPH, chair of Henry Ford's Department of Public Health Sciences and principal research investigator.

The gut microbiome is the collection of microorganisms in the gastrointestional, or GI, tract, and the human body has billions of these microbes... The gut microbiome is known to play an important role in immune system development, and is thought to contribute to a host of diseases like obesity, autoimmune diseases, circulating disorders and pediatric allergies and infection.

"For years now, we've always thought that a sterile environment was not good for babies. Our research shows why. Exposure to these microorganisms, or bacteria, in the first few months after birth actually help stimulate the immune system," Dr. Johnson says."The immune system is designed to be exposed to bacteria on a grand scale. If you minimize those exposures, the immune system won't develop optimally."

In six separate studies, researchers sought to evaluate whether breastfeeding and maternal and birth factors had any effect on a baby's gut microbiome and allergic and asthma outcomes. Using data collected from the WHEALS birth cohort, researchers analyzed stool samples from infants taken at one month and six months after birth. They also looked at whether the gut microbiome impacted the development of regulatory T-cells, or Treg, which are known to regulate the immune system. Highlights:

Breastfed babies at one month and six months had distinct microbiome compositions compared to non-breastfed babies. These distinct compositions may influence immune system development.Breastfed babies at one month were at decreased risk of developing allergies to pets. • Asthmatic children who had nighttime coughing or flare-ups had a distinct microbiome composition during the first year of life. • For the first time, gut microbiome composition was shown to be associated with increasing Treg cells.

Researchers found that a baby's gut microbiome patterns vary by: • A mother's race/ethnicity. • A baby's gestational age at birth. • Prenatal and postnatal exposure to tobacco smoke. • Caesarean section versus vaginal delivery.• Presence of pets in the home.

Henry Ford's landmark 2002 study found exposure to dogs or cats in the first year of a baby's life reduced their risk for allergies.

The following study raises the question  of how to lower BPA levels in all people, not just children with autism spectrum disorder.

The absolute quickest and easiest is to buy (whenever possible) loose foods (fresh fruits, vegetables, breads, etc) or foods in glass containers (and not plastic bottles, jars, or containers), store food in glass, porcelain, or stainless steel containers, and microwave in glass dishes (and not plastic containers).

In other words, think glass and not plastic. This is because BPA is in polycarbonate containers or packaging.

Lower your use of canned foods and avoid soda in cans. This is because cans have a lining that contains BPA or a BPA substitute (and research suggests it has the same effects as BPA). By the way, clear cling wrap made from polyethylene is considered safe to wrap and store food in.

From Medical Express: New study links BPA exposure to autism spectrum disorder

A newly published study is the first to report an association between bisphenol-A (BPA), a common plasticizer used in a variety of consumer food and beverage containers, with autism spectrum disorder (ASD) in children. The study, by researchers at Rowan University School of Osteopathic Medicine (RowanSOM) and Rutgers New Jersey Medical School (NJMS), shows that BPA is not metabolized well in children with ASD. The research appears online in Autism Research.

"It has been suspected for a lot of years that BPA is involved in autism, but there was no direct evidence," said T. Peter Stein, of RowanSOM and the study's lead author. "We've shown there is a link. The metabolism of BPA is different in some children with autism than it is in otherwise healthy children."

The research team – which included Margaret Schluter and Robert Steer, of RowanSOM who were responsible for laboratory analysis, and child neurologist Xue Ming, of NJMS who recruited and ascertained the study populations – examined urine specimens from 46 children with ASD and 52 healthy control children for both free BPA and total BPA concentrations.

Like many chemicals, BPA becomes water soluble when it is bound to glucose in the liver – a process called glucuronidation. Conversion to a glucuronide and then excretion of the glucuronide in the urine is a major pathway for removing toxins from the body.

The researchers also conducted a metabolomic analysis to screen for all the chemicals found in the children's urine. The metabolomics analyses showed the mean number of statistically significant correlations between metabolites detected and total BPA excreted to be approximately three times greater with the ASD group than the controls, and the number of statistical significant correlations with fraction of BPA bound was approximately 15 times higher in the children with ASD (p<0.001).

"Other studies involving rodent data have shown that BPA functions as an endocrine disruptor, but ours is the first to show this in humans and the first to associate it to autism," Stein said. "The observations show that for some children there was a relationship between intermediary metabolism, the ability to conjugate BPA and symptoms of autism."

Although the study involves a relatively small number of subjects, Stein said, "The key point is that the study seems to link BPA to autism and creates an open area for further research. One implication of our study is that there might be a benefit to reducing BPA exposure for pregnant women and for children with autism."

A big study that found that eating a greater proportion of plant-based foods (fruits, vegetables, grains, beans, potatoes, nuts, olive oil), as compared to animal-based foods, is linked to lower risks of dying from heart disease and stroke.

From Science Daily: Semi-veggie diet effectively lowers heart disease, stroke risk.

A pro-vegetarian diet -- one that has a higher proportion of plant-based foods compared to animal-based foods is linked to lower risks of dying from heart disease and stroke, according to new research presented at the American Heart Association EPI/Lifestyle 2015 meeting. In an observational study, researchers analyzed the eating and lifestyle habits of 451,256 Europeans.

People who ate the most pro-vegetarian style diets (up to 70 percent of food coming from plant sources) had a 20 percent lower risk of dying from cardiovascular disease, compared to those who were the least pro-vegetarian (<45 percent). "A pro-vegetarian diet doesn't make absolute recommendations about specific nutrients. It focuses on increasing the proportion of plant based foods relative to animal-based foods, which results in an improved nutritionally balance diet," said Camille Lassale, Ph.D., lead author and an epidemiologist at Imperial College London's School of Public Health.

Participants were part of the European Prospective Investigation into Cancer and Nutrition (EPIC) study, started in 1992. The study included nearly half a million people from 10 countries who were free of chronic diseases at the start of the study, 35 to 70 years and followed for 12 years on average....Researchers scored participants based on the types of foods they ate. Points were given for eating foods from seven plant food groups: vegetables, fruit, beans, cereals, potatoes, nuts, and olive oil. Points were subtracted for five animal food groups: meats, animal fats, eggs, fish, and other seafood or dairy products. Based on their scores, participants were categorized from the least pro-vegetarian to the most. 

Researchers analyzed the relationship between eating habits and death risks from heart disease and stroke."Instead of drastic avoidance of animal-based foods, substituting some of the meat in your diet with plant-based sources may be a very simple, useful way to lower cardiovascular mortality," said Lassale. These findings are in line with the wealth of evidence on benefits of eating plant foods to prevent CVD.

The American Heart Association recommends following a heart-healthy diet, which could also be described as a pro-vegetarian diet. It is high in fruits, vegetables, whole grains, legumes, beans, and nuts, low-fat dairy, beans, skinless poultry, and fish. It encourages eating foods low in saturated and trans fats and sodium, and limiting added sugars and red meats.

The last few years have been brutal for those unemployed and having trouble finding employment. Some recent studies highlight how devastating being laid off and unemployed is to one's mental and physical health.

From Science Daily: Stress markers in unemployed linked to poor health

It appears that stress markers in unemployed people can be found, independent of smoking, alcohol consumption and overweight/obesity. Results from a study suggest that long-term unemployment may be especially damaging to health. Authors also note that older job seekers appear more affected than younger counterparts.

Research from the ESRC International Centre for Lifecourse Studies at UCL suggests direct biological effects of stress during unemployment may help explain the increased mortality and morbidity among job seekers. The study used biological signatures in blood samples called inflammatory markers, which are influenced by stress and are clinically important because mildly raised levels predict atherosclerosis (narrowing of the arteries due to fatty deposits) and heart disease.

From Medical Xpress: One in five suicides is associated with unemployment

Every year, around 45,000 people take their own lives because they are out of work or someone close to them is affected by unemployment, as a study by the University of Zurich now reveals. It includes data of 63 countries and demonstrates that during the 2008 economic crisis the number of all suicides associated with unemployment was nine times higher than previously believed.

Unemployment can drive people to suicide. Numerous studies have demonstrated that there is a relationship between unemploymentand poor health and that (the threat of) losing a job and prolonged unemployment can constitute a serious situation for those affected as well as their relatives...Every year, around one in five suicides is associated with unemployment," says first author Carlos Nordt.

Every year, almost a million people die by suicide worldwide. In order to find out how many suicides are associated with unemployment, the UZH researchers included data from 63 countries between 2000 and 2011 in their study. The countries were divided into four regions: North and South America, northern and western Europe, southern and eastern Europe, and Non-Americas and non-Europe. No data was available from China or India. "Despite country-specific particularities, we found a similarly strong association between unemployment and suicide rates in all four regions," summarises sociologist Nordt. Moreover, a changing unemployment rate affected both sex as well as different age groups equally.

From Medical Xpress: Unemployment changes your core personality, according to study

The psychological damage caused by unemployment is greater than previously thought, according to a study led by researchers at the University of Stirling. Stirling's behavioural scientists have found that unemployment, well-known to cause substantial drops in personal well being, can also cause large changes to a person's core personality.

Personality is typically considered stable across time but the researchers found that the experience of unemployment led to reduced levels of conscientiousness, agreeableness, and openness; signifying that individuals lose motivation, become less considerate and sympathetic, and less curious about the world around them. These changes were greater the longer an individual spent unemployed.

Lead researcher Dr Christopher Boyce, from the University of Stirling's Behavioural Science Centre, said: "The results challenge the idea that our personalities are 'fixed' and show that the effects of external factors such as unemployment can have large impacts on our basic personality."

A large study found that eating nuts or peanuts several times a week is associated with lower death rates, especially from cardiovascular disease. Note that a serving is a small handful or 1.5 ounces of whole nuts or 2 tablespoons of nut butter.

From Science Daily: Peanut consumption associated with decreased total mortality and mortality from cardiovascular diseases

If you're looking for a simple way to lower your risk of dying from a heart attack, consider going nuts. Researchers at Vanderbilt University and the Shanghai Cancer Institute examined the association of peanut and nut consumption with mortality among low-income and racially diverse populations and found that intake of peanuts was associated with fewer deaths, especially from heart disease.

"Nuts are rich in nutrients, such as unsaturated fatty acids, fiber, vitamins, phenolic antioxidants, arginine and other phytochemicals. All of them are known to be beneficial to cardiovascular health, probably through their anti-oxidative, anti-inflammatory and endothelial function maintenance properties," Shu said.

While research has previously linked nut consumption with lower mortality, those studies focused mainly on higher-income, white populations. This study was the first to discover that all races -- blacks, whites and Asians alike -- could potentially increase heart health by eating nuts and peanuts.

This study was based on three large ongoing cohort studies. Participants included more than 70,000 Americans of African and European descent from the Southern Community Cohort Study (SCCS), who were mostly low-income, and more than 130,000 Chinese from the Shanghai Women's Health Study (SWHS) and the Shanghai Men's Health Study (SMHS).... In total, more than 14,000 deaths were identified, with a median follow-up of 5.4 years in the SCCS, 6.5 years in the SMHS, and 12.2 years in the SWHS.

Peanut consumption was associated with decreased total mortality, particularly cardiovascular mortality (i.e., 17-21 percent reduction in total mortality, and 23-38 percent reduction in cardiovascular mortality for the highest quartile intake group compared to the lowest quartile group) across all three racial/ethnic groups, among both men and women, and among individuals from low-SES groups.

The American Heart Association recommends eating four servings of unsalted, unoiled nuts a week. However, nutrient-rich nuts are also high in calories, so don't eat too many if you're watching your weight. A serving size is a small handful or 1.5 ounces of whole nuts or 2 tablespoons of nut butter.

More research linking moderate coffee consumption with a health benefit. From Medical Daily:

Moderate coffee consumption lessens risk of clogged arteries and heart attacks

People who drink a moderate amount of coffee daily are less likely to develop clogged arteries that could lead to heart attacks, reveals research published online in Heart. Researchers from South Korea found that people consuming three to five cups a day had the least risk of coronary calcium in their arteries.

There has been much debate over the effect of coffee consumption on cardiovascular health.Despite earlier concerns about a potential increase in heart disease risk associated with drinking coffee, a recent meta-analysis of 36 studies showed that moderate coffee consumption was associated with a decreased risk of heart disease. Coffee consumption has been associated with improved insulin sensitivity and reduced risk of type 2 diabetes, but it has also been linked to increased cholesterol concentrations and heightened blood pressure.

An international team of researchers led by the Kangbuk Samsung Hospital, Seoul, in the Republic of Korea, set out to examine the association between coffee consumption and the presence of coronary artery calcium (CAC) which is a early indicator of coronary atherosclerosis - a potentially serious condition where arteries become clogged up by fatty substances known as plaques or atheroma and which can cause the arteries to harden and narrow, leading to blood clots which can trigger a heart attack or a stroke.

They studied a group of 25,138 men and women - average age of 41 - who had no signs of heart disease, attending a health screening examination...They categorised coffee consumption as none, less than one cup a day, one to three cups a day, three to five per day and at least five or more per day. The researchers found the prevalence of detectable CAC was 13.4% amongst the whole group of people and the average consumption of coffee was 1.8 cups per day.

The calcium ratios were 0.77 for people who had less than one cup per day, 0.66 for those having one to three cups every day, 0.59 for those consuming three to five cups per day, and 0.81 for people having at least five cups or more every day compared with non coffee drinkers. The association was similar in subgroups defined by age, sex, smoking status, alcohol consumption, and status of obesity, diabetes, hypertension, and hypercholesterolaemia. The association, therefore, was U-shaped, with participants drinking three to five cups per day having the lowest prevalence of arteries that had clogged up.

Possible explanations for the findings, said the researchers, were that chronic coffee consumption had a possible link to reduced risk of type 2 diabetes, a strong risk factor for atherosclerosis, and that coffee drinking might improve insulin sensitivity and β-cell function.The authors concluded: "Our study adds to a growing body of evidence suggesting that coffee consumption might be inversely associated with CVD [cardiovascular disease] risk.

More than a year after California revised its flame retardant standards so that new furniture (the polyurethane foam in upholstered sofas, sofa beds, and chairs) does not have to use flame retardants, it is still hard to find out whether the furniture is flame retardant free. This is what I have experienced in the last few months - the store doesn't know and the manufacturer won't respond to emails.

The new furniture label should say TB 117-2013 , and then you still need to ask the retailer if there are flame retardants in the upholstered furniture. The new label means that the manufacturer does NOT have to use flame retardant chemicals anymore, but it does NOT mean they are chemical free. And flame retardants are still found in many baby products (car seats, bumpers, crib mattresses, strollers, nursing pillows, etc), some personal care products, and electronics. It's a buyer beware situation.

More and more research is finding health problems with flame retardants because they are "not chemically bound" to the products in which they are used - thus they escape over time, and get into us via the skin (dermal), inhalation (from dust), and ingestion (from certain foods and dust on our fingers). And because flame retardants are persistant, they bioaccumulate (they build up over time). They can be measured in our urine and blood.

Evidence suggests that flame retardants may be endocrine disruptors, carcinogenic, alter hormone levels, decrease semen quality in men, thyoid disruptors, and act as developmental neurotoxicants (when developing fetus is exposed during pregnancy)  so that children have lowered IQ and more hyperactivity behaviors.

How does one know if the foam in your furniture has flame retardants in it? Duke University will test it for free if you send them a small piece of the furniture's foam. http://sites.nicholas.duke.edu/superfund/whats-in-my-foam/ I originally read about this service a few months ago in The Atlantic,

From The Atlantic: How to Test a Couch for Toxins

It began with a smell. Kerri Duntley had just bought a pair of large, cream-colored couches....As the scent continued to fill her living room, Duntley asked herself a troubling question: What was causing the couches to smell like industrial chemicals? The answers weren’t easy to find. Duntley searched in web forums and even tried contacting the couches’ manufacturer. “I called and called and called,” she said. “They just would not give me the information.” She grew frustrated and began looking for new couches. It was then that she discovered an unusual service run by a Duke University lab.

The lab’s offer was simple. First, the lab instructed, wield a pair of scissors. Grab something made with polyurethane foam—say, a mattress or the innards of a couch cushion. Cut a small chunk from the foam. Wrap the surgical work in tinfoil, ziplock seal it and mail the crime-scene-looking evidence off to Durham, North Carolina. Wait up to 45 days, the lab said, and it’ll arrive: a report detailing toxic flame retardants embedded in the foam.

Duntley complied. When the results came back, she learned that her couch sample had tested positive for two flame retardants, including one that has proven harmful in animal studies, a finding that she called heartbreaking. Her experience points to a vast gap in safety information about consumer goods. With the U.S. government’s limited power to regulate chemicals, many consumers, like Duntley, are left to piece together their own crude health-risk assessments. That fabric softener? It may smell like the Elysian Fields, but what if its unlisted ingredients cause cancer? 

Government officials , academic researchers, the chemical industry and environmentalists agree: The U.S. system of chemical regulation is broken. But while the fight over reform continues in Washington, consumers remain blind to many of the chemicals that enter their homes.

Duke’s service is looking in its small way to change that. The lab—which offers anyone a free chemical analysis of polyurethane foam—has informed hundreds of Americans about their furniture’s toxicity. At the same time, the foam samples have given Duke’s team a large bank of crowdsourced research. By offering a free service to an anxious public, Duke’s scientists are gaining a clearer view of chemical manufacturing. And they’re learning just how much we don’t know about the chemicals that enter our homes.

Stapleton was part of a scientific cohort that found ingesting dust—say, getting our dusty hands on a burger—is by far our largest source of exposure to flame retardants; flame retardants aren’t chemically bound to their products, and so they attach themselves to airborne dust.

But what began in California soon became a de facto national standard, since furniture companies didn’t want to manufacture separate lines. Stapleton was interested to see how chemically saturated our furniture really is. So she and her colleagues asked families for samples of their baby products’ foam. After reviewing 101 samples from across thirteen states, Stapleton’s 2011 study reached a startling conclusion: Flame retardants accounted for about 5 percent of the products’ weight, and the chemicals were found in 80 percent of the samples.

Some of the chemicals were carcinogens. Others were from a chemical class known as polybrominated diphenyl ethers, or PBDEs, which have been linked to lower IQ scores, attention deficit hyperactivity disorder, and thyroid disorders. The most common flame retardant among the samples was tris (1,3-dichloroisopropyl)phosphate, or TDCPP, which researchers say is likely to harm the neurological development of infants. TDCPP, in fact, was used throughout the 1970s in children’s pajamas, until critical health research led manufacturers in 1977 to stop using it. Yet the chemical had reemerged in products like strollers and baby mattresses.

The lab offered to test some of these strangers’ furniture for free. But the requests kept coming. That’s when Stapleton and her colleagues decided to expand the scope of the testing and conceived of a free service for the public. They’d test anyone’s polyurethane foam for a suite of seven common flame retardants as something of a public service, since it would be funded by a federal grant (itself funded by taxpayer dollars). The service would also aid Stapleton’s research, offering a valuable stream of crowdsourced data about the chemicals used in furniture.

By crowdsourcing her research, Stapleton has also uncovered a flame retardant that academic literature has yet to identify. The flame retardant is a chlorinated organophosphate, like TDCPP, and its health effects are unknown, she said. Stapleton said that this recent discovery-by-accident followed the same pattern as her research on Firemaster 550, a popular flame retardant that replaced two widespread PBDEs after they were withdrawn from the market... But emerging research has raised concerns about Firemaster 550, too. One study from Boston University and Duke researchers found that the chemical mixture may cause obesity in humans. Stapleton found the same effect in rats.