The main causes of obesity are eating too much and exercising too little. But a new study has found a link between child obesity and exposure to certain chemicals found in plastic. Is it possible that there is more to the obesity epidemic than we previously thought? Are there other steps parents should take to help prevent obesity in our children? How can a parent avoid the toxic chemicals in plastic when it seems that plastic is everywhere?
A long-term study of East Harlem girls performed by researchers at Mount Sinai Hospital found that exposure to certain chemicals used in plastic may be linked with childhood obesity. The specific chemicals are called phthalates, which are used to make plastics pliable and in personal care products.
Phthalates are absorbed into the body and affect the glands and hormones that regulate many bodily functions. In this sense, they are considered ‘endocrine disruptors’. Studies have long suggested that these chemicals may cause cancer but this is the first study that suggests that they may promote obesity, as well.
Animal studies also support the notion that these chemicals may cause obesity. Bisphenol A (also used in plastics)and perffluorooctanoic acid (used in non-stick surfaces) have been shown to promote obesity in mice. But this new study from Mount Sinai is the first to show a link between chemicals and obesity in humans.
In this study, researchers looked at the level of phthalates in the urine of 400 East Harlem girls, who range in age from 9 to 11. “The heaviest girls have the highest levels of phthalates metabolites in their urine,” said Dr. Philip J. Landrigan, a professor of pediatrics at Mount Sinai, one of the lead researchers on the study. “It goes up as the children get heavier, but it’s most evident in the heaviest kids.”
Not only were the phthalate levels higher in the heavier children as compared to the leaner kids, but the levels in all of the kids studied were significantly higher than the average levels measured by the CDC for kids throughout the country. This may help explain why children in this neighborhood have a higher overall obesity rate (40%) than kids in the rest of the country (33%).
This study may change how we think about obesity. Perhaps diet and exercise are not the only major players involved. Environmental exposure to toxins, such as these chemicals found in plastic, may be more important than previously recognized.
It is important to point out, however, that this study does not prove that exposure to these chemicals causes obesity. Right now, it just seems to be linked to obesity. It could simply be an accidental finding that has no causal relationship with obesity at all.
This question will be looked at further in a larger study that will monitor 100,000 children across the country.
So what can a parent do now? It is likely best to reduce exposure to pthalates as much as possible. Unfortunately, these chemicals are so widely used that it is impossible to avoid them completely. Further complicating the problem, labels usually don’t identify phthalates.
Phthalates are used in a large variety of products, from enteric coatings of pharmaceutical pills and nutritional supplements to viscosity control agents, gelling agents, lubricants, and emulsifying agents used in products such as adhesives and glues, building materials, personal care products,medical devices, detergents, packaging, childrens’ toys, modelling clay, waxes, cleaning materials, paints, printing inks and coatings, pharmaceuticals, food products and textiles. Phthalates are also frequently used in soft plastic fishing lures, nail polish, adhesives, caulk and paint pigments. Phthalates are used in a variety of household applications (shower curtains, adhesives, perfume), modern electronics and medical applications such as catheters and blood transfusion devices.
The most widely-used phthalates are the di-2-ethyl hexyl phthalate (DEHP), the diisodecyl phthalate (DIDP) and the diisononyl phthalate (DINP). DEHP is the dominant plasticizer used in PVC, due to its low cost.
As of 2004, manufacturers produced about 363 thousand metric tonnes (800 million pounds or 400,000 short tons) of phthalates each year.
The best thing a parent can do is to learn to recognize the abbreviations for the most common phthalates (mentioned above) and to opt for certain kinds of recyclable plastics over others. We also need to urge the FDA to mandate the identification and labeling of products using these chemicals so consumers can make knowledgable choices when selecting these products.