Childhood Obesity Linked to Chemicals

BPA and phthalates are obesogens


It seems you can’t open a newspaper these days without seeing an article about childhood obesity or recommendations for getting kids to be more active. But parents may be surprised to learn that while diet and exercise are important factors in a healthy lifestyle, certain chemicals that kids are exposed to every day could also be having an impact on their weight.

Scientists have found that some chemicals known to be endocrine disruptors, meaning substances that can mimic or interfere with hormones, are also "obesogens".

Recent research on phthalates, widely used substances in plastics and personal care products, and BPA, used in food can linings and receipts, adds to the evidence that exposure to toxic chemicals is partly to blame for the obesity epidemic.

The research shows that low dose exposures to BPA (even below "safe" thresholds specified by health agencies) can induce fat cell development in mice. According to another recent study, BPA exposure during pregnancy is also linked to higher risk of becoming obese in childhood.

Phthalates are known to be linked to other health effects including diabetes, and developmental and reproductive problems. But, according to a 2016 study from the University of Leipzig in Germany, these chemicals, often found in scented body soap or in plastic food packaging, can also facilitate unhealthy weight gain by promoting fat cell production in our bodies.

Researchers studied the effects of exposing mice to human-equivalent daily levels of DEHP (di-2-ethylhexyl-phthalate). They found that regardless of diet, mice that were exposed to these phthalates were more likely to become obese, particularly female ones. While cosmetics makers are not supposed to add DEHP to products sold in Canada, other phthalates such as diethyl phthalate (DEP) and dibutyl phthalate (DBP) are widely used in plastics including food packaging, flooring, and fragranced products.

The findings from the University of Leipzig study are consistent with epidemiological evidence (research at the human population level). A study of New York City children found a positive association between bodily concentrations of phthalates and being overweight. A panel of experts in Brussels also concluded that hormone disrupting chemicals, like phthalates, are partly to blame for the rise of childhood obesity and a major review in 2017 confirmed a link between obesity and BPA.

Time for a conversation shift

Obesity rates in Canada are at record levels, with one in four Canadians being obese, and one in ten Canadian children being clinically obese. Many blame the consumption and widespread marketing of fast food and our increasingly sedentary lifestyles, but it is time that we include another important factor: environmental exposure to chemicals such as phthalates.

According to Statistics Canada in 2018, 27 per cent of Canadians are obese and prone to develop serious health outcomes as a result, like diabetes. Obesity costs Canadians $2- $6 billion every year. While helping Canadians to maintain a healthy diet and increasing physical activity are crucial, curbing exposures to hormone disrupting chemicals, like phthalates, should be an important part of proposed policy solutions to address the rise of obesity, diabetes, and heart disease.

In 2011, the federal government took a good first step in reducing Canadian children’s exposure to certain phthalates by restricting certain types of phthalates in toys. But that partial ban falls short in protecting children from these harmful chemicals.

Reducing kids’ exposure to BPA and phthalates

When it comes to health, size isn’t everything, but some of the chemicals linked to obesity are tied to other health problems as well, and it’s a good idea for parents to take steps to reduce exposure. 

*Originally published June 26, 2016