Animal studies suggest that certain common chemicals may trigger increased fat cell activity or adipogenesis. Sometimes, I think just looking at certain delectable goodies makes my fat cells grow. But this, my friends, is a serious report on a serious subject.
According to a story in the Washington Post, Bruce Blumberg, a developmental and cell biologist at the University of California at Irvine, presented research at the annual meeting of the American Association for the Advancement of Science on compounds he calls “obesogens”—chemicals that promote obesity.
Blumberg studied the effects of tributyltin, a chemical used as an antimicrobial agent in industrial water systems, as an antifungal in marine and agricultural settings, and is used in the production of plastics.
“What we discovered,” Blumberg said, “is that tributyltin disrupted genetic interactions that regulate fat-cell activity in animals. Exposure to tributyltin is increasing the number of fat cells, so the individual will get fatter faster as these cells produce more of the hormones that say ‘feed me’.” The exposed animals, he added, remain predisposed to obesity for life.
Another suspected obesogen is bisphenol A. It is used in plastic products ranging from refillable water containers to baby bottles. It is also a part of the epoxy resins that line the inside of food cans and are used as dental sealants. A study by the Centers for Disease Control and Prevention found bisphenol A in 95% of the people tested, at levels at or above those that affected development in animal studies.
According to Frederick vom Saal, another researcher quoted in the Washington Post article, research indicates that developmental exposure to low doses of bisphenol A activates genetic mechanisms that promote fat-cell activity. “These in-utero effects are lifetime effects, and they occur at phenomenally small levels” of exposure, vom Saal said.
The American Chemical Council responds
The American Chemical Council (ACC) pooh-poohs the idea that these chemicals are harmful to human beings. But many researchers disagree. Vom Saal even goes so far as to call the ACC’s statements about the safety of these agents a “blatant lie”.
It is too early to say definitively who is right and who is wrong. But, the animal research is certainly suggestive enough to justify larger scale animal studies, including studies designed to look at the toxicity of these chemicals in human beings.
For those of you who are hoping it’s the toxins in plastic that made you fat, I have to say that I sympathize. But even if these chemicals are playing a role in packing our fat cells with fat, it is highly likely that the biggest culprit in the global obesity epidemic is still going to be too many calories and too little exercise.