Another Subset of Endocrine Disrupters
Pretty much everyone's heard about chemicals that interfere with the normal function of hormones. At least 800 of these "endocrine disrupters" have been identified and of particular interest are estrogen mimickers (xenoestrogens or phytoestrogens) that induce estrogen-like effects in women and men.
This surplus of estrogen could lead to breast, prostate, and testicular cancer, in addition to infertility, diabetes, storage of body fat, difficulty in gaining muscle, and even psychological effects. Scientists have recently, however, identified another subset of endocrine disrupters that specifically cause you (or your offspring) to become fat. They're called "obesogens."
While lousy diet and lack of exercise are leading causes of the obesity epidemic, researchers are starting to suspect that these obesogens might be an under-recognized third factor.
The pesticide DDT was probably one of the first obesogens. It's elicited a lot of curiosity among scientists because there probably wasn't a pregnant woman alive in the 1950's who didn't come into contact with it.
When scientists exposed rats to DDT, it didn't have much of an effect on them. Oddly enough, though, in what appears to be a case of transgenerational epigenetic inheritance, it caused many of the grandchildren of exposed rats to become fat.
So when you see that more than a third of Americans are currently obese, scientists like Mike Skinner and his associates at Washington State University started to wonder if the DDT that their grandmothers were exposed to played a role.
After much study, Skinner's group and others theorized that DDT and other obesogens like dicyclohexyl phthalate (a plasticizer), and various pesticides are influencing our endocrine systems adversely. While some obesogens like DDT seem to reach across the generations to tap unfortunate offspring with the fat wand, other obesogens seem to have a direct fat-causing effect on exposed individuals.
It seems that obesogens in general activate the glucocorticoid receptor and promote fat cell differentiation and the build-up of lipids. In other words, they muck up insulin signaling and cause fat cells to become insulin resistant so that when obesogen-exposed animals are fed a high-fat diet, they handle calories differently – they get fatter faster.
Another fat-growing mechanism involves obesogen-activation of a fatty acid receptor called PPARy, which is the master regulator of fat-cell development. And you can't forget the estrogen-mimicking component of some of these obesogens. They cause fat to accrue through different pathways and could be responsible for "man boobs" and/or the inability to get ripped.
To compound the problem, these chemicals establish homesteads in fat cells and refuse to leave... at least not until you lose an appreciable amount of body fat, which releases some of these chemicals back into the bloodstream (which could potentially be problematic on a whole other front, least of all from starting the whole fat-accruing cycle all over again). Put it all together and it spells fatness.
These chemicals don't break down, at least not without divine intervention. They're in the air and water and they travel unimpeded around the world.
They're found in flame-retardants in mattresses and pillows. They're in your computer, in the wall insulation, the insides of cans, and the lining of microwave popcorn bags. They're floating in the air, clinging to dust particles. Screw it, they're everywhere.
There are things you can do to reduce your exposure, though. While following everything on the list below would require you to revert to a pre-pre-industrial lifestyle where you eschew clothing, soap, and man-made materials in general and sit naked in a field picking insect vermin out of your graying pubes until you die, doing a few of them might serve you, and definitely your offspring, well.
- Avoid using pesticides in your yard.
- Remove your shoes when you come in the door so you don't track pesticides and other chemicals into your house.
- Clean and dust surfaces often. Mop the floor regularly. (And don't let Junior crawl around on the floor until you do.)
- Avoid air fresheners, fabric softeners, and personal care products that contain phthalates.
- Don't buy non-stick cookware. Choose cast iron or stainless steel.
- Don't eat store-bought microwave popcorn as the bags are lined with the obesogen PFOA. (Here's how to make popcorn and avoid the chemical-lined bags: The Healthiest Snack Food.)
- Don't store food in plastic containers. Use glass instead.
- Avoid eating foods that come wrapped in plastic.
- Try to buy organic food (many fungicides and insecticides are obesogens).
- Don't buy toys made with phthalates. Watch out for words like vinyl or PVC and the #3 recycling code. Watch out for a plasticky smell.
- Avoid stain and water-protecting treatments on furniture and carpets.
- Use natural cleaning products in your home.
- Work up a sweat as often as possible, as this helps rid the body of any recently acquired obesogens that have yet to establish residence in fat cells.
- La Merrill M et al. Toxicological Function of Adipose Tissue: Focus on Persistent Organic Pollutants. Environ Health Perspect. 2013 Feb;121(2):162-9. PubMed.
- Grens K. Obesogens – Low doses of environmental chemicals can make animals gain weight. Whether they do the same to humans is a thorny issue. The Scientist. November 1, 2015.