Why chemicals in plastics could be making you fat

Chemicals in plastics mimic hormones to disrupt the body's metabolism and cause obesity, according to a new study.
Written by Andrew Nusca, Contributor

Are plastics making us fat?

Chemicals in plastics that mimic hormones are already known to be endocrine disruptors in the body. But new research indicates that these chemicals -- such as bisphenol A, or BPA, found in some types of water bottles -- also disrupt the body's metabolism, potentially predisposing people to obesity.

That's not to say overeating and a lack of exercise aren't to blame for the obesity epidemic facing the U.S. and other nations. But the findings may make us rethink how we manufacture goods.

Wherever you look, you'll find BPA and pthalates. From dryer sheets in your laundry to the PVC pipes that line the inside of your house. Coined "obesogens" by Bruce Blumberg, a leading researcher on the issue, the chemicals are gaining attention, as evidenced by a recent Newsweekstory on the subject:

In 2006 scientists at the Harvard School of Public Health reported that the prevalence of obesity in infants under 6 months had risen 73 percent since 1980. "This epidemic of obese 6-month-olds," as endocrinologist Robert Lustig of the University of California, San Francisco, calls it, poses a problem for conventional explanations of the fattening of America. "Since they're eating only formula or breast milk, and never exactly got a lot of exercise, the obvious explanations for obesity don't work for babies," he points out. "You have to look beyond the obvious."

How does this occur? Rachel Cernansky at Planet Green explains:

A potential explanation is that the compounds disrupt the body's circadian rhythm and may cause weight gain by, for example, programming the body's clock to eat when it should be sleeping.

The effects can also take place during developmental stages: as a Japanese study of cells growing in lab dishes showed, cells that would normally become fibroblasts, or connective tissue, actually became fat cells in the presence of industrial compounds like BPA...in the study, existing fat cells were also stimulated to grow faster and more plentiful.

That means newborns are at risk of these industrial compounds converting undeveloped precursor cells into fat cells, which could alter the body's metabolism and prompt it to store calories rather than burn them.

In other words: your baby may be overweight because you're feeding it too much, but it may also be because it's chemically predisposed to it, too.

Obesogens will for the first time be a major focus at a government-sponsored meeting this fall, with scientists from the National Institutes of Health, the Food and Drug Administration, the Environmental Protection Agency and academia in attendance.

The meeting, the largest such event on the topic, shouldn't be a surprise: health care is currently a highly-contested issue in the U.S., and costs for overweight or obese Americans run 43 percent higher, thanks to higher levels of type 2 diabetes, heart disease and other conditions.

This post was originally published on Smartplanet.com

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