“Today, more than 84,000 chemicals are on the Environmental Protection Agency’s (EPA) inventory of chemicals in the U.S., and an average of more than 700 new chemicals are introduced each year. The existing law regulating the safety of these chemicals—TSCA—is so broken that the Government Accountability Office placed it on its list of “high risk” areas of the law in a 2009 report. As a result, the Centers for Disease Control and Prevention (CDC) has found more than 212 industrial chemicals in Americans’ bodies, including at least six known carcinogens and dozens that are linked to cancer, birth defects, and other diseases.
In part 1 of this interview, Dr. Susan Katz, a retired pediatrician, biochemist, and present Chair of the Environmental Health Work Group of the Oregon’s Physicians For Social Responsibility (PSR) talks about some of the new research on “obesogens”, the specific class of chemicals that appear to promote weight gain in humans and possibly other mammals.
As the prevalence of obesity worldwide has roughly doubled since 1980 to present levels (over 1 in 3 U.S. adults are now obese), even among medical professionals—physicians, nutritionists, and other specialists, obesity is often seen as mainly a result of these two factors: poor diet and sedentary lifestyle.
While it is generally understood that individual heredity plays a distinct role in determining ones likelihood toward becoming overweight or obese, in the simplest of terms, those who consume more daily calories than their bodies can readily use, the excess calories are stored within the fat cells (their fixed number and size determined during fetal development), the more calories stored, the more weight that’s gained.
Overconsumption of sodas, fast food, and other highly processed foods are widely seen as greatly contributing to the problem of obesity and overweight.
But what if there’s more to this story that may account for the steep rise in the overweight and obesity rates that have occurred over the past 30 years?
As Dr. Katz explains in this video, no one is arguing that diet and lifestyle choices are not important factors, but there’s been a flurry of new scientific evidence to suggest that certain chemicals we are being exposed to from our environment, and in the food we eat, may also be a major contributor to the weight gain problem. Even more alarming, there is early evidence to suggest that epigenetic effects, that is, exposure during pregnancy of the developing fetus to a certain class of chemicals called “obesogens,” may cause permanent metabolic changes, and changes to fat cells (their number, distribution, and size) that will preordain (or shift the balance toward) a person becoming overweight or obese, throughout their life. Worse still, even though epigenetic effects do not alter the DNA itself, their effects may be passed down to future generations.
No one knows the longterm effects of chronic, low level exposure to a growing list of modern industrial chemicals found in human populations that didn’t exist 50 or 100 years ago. Perhaps, until better understood, policymakers will consider the emerging scientific evidence, and choose to err on the side of safety by restricting their use.
In the meantime, only time will tell, how big a problem we may have heaped upon our plate.
Coming Thursday, part 2: Dr. Katz offers practical advice on ways to reduce exposure to some of these potentially dangerous chemicals, and shares some reliable resources where to turn for more information.