Environmental Contaminants Causing Weight Gain?

Ever suspect you might have a sluggish thyroid? Low thyroid function will slow down your metabolism and the obvious symptoms are weight gain and fatigue. Sound familiar?

Now, a new study adds to the accumulating research implicating what some in the integrative medicine community have long suspected -- a connection between environmental toxins and thyroid dysfunction.

While there is no conclusive proof that these are connected, the data is building.

The new study from the University of Exeter in England looked at blood samples from about 4,000 people and measured the concentrations of a nasty little chemical called perflurooctanoic acid (PFOA) and perfluoroocatnoic sulfonate (PFOS). Both are found in Teflon, the non-stick coating widely used in pots and pans. Those with the highest amounts of these chemicals in their blood were twice as likely to report thyroid problems than those with the lowest amounts.

The researchers noted that more studies were needed to see if thyroid problems predisposed people to take up these chemicals in greater amounts, or whether the chemicals were decreasing thyroid function. Also, the study did not specifically look at weight gain and chemical exposure.

This isn't the first time the connection between Teflon and thyroid has come up, however. Back in 2008, a study of 69,000 people in Ohio and West Virginia found that elevated levels of these same chemicals in the bloodstream harmed the thyroid as well as the immune system and liver. That study was funded by some of the money from a $107.5 million settlement paid by the DuPont company -- which makes Teflon -- to settle a lawsuit over the company's dumping PFOA in the region's water supply. Nice.

Interestingly, and tellingly, it only took "moderate" levels of exposure to affect the thyroid.

In one animal study, the offspring of pregnant mice that were exposed to these chemicals were heavier than their counterparts whose mothers were not exposed to PFOA.

But Teflon's hardly the only source of chemicals that may alter thyroid function. Endocrine disruptors from Bisphenol A to a group of flame retardants known as polybrominated diphenyl ethers, or PBDEs, are being studied for their effect on thyroid function. There's long been a vocal contingent of nutritionists, doctors and health practitioners who worry that goitrogens (thyroid disrupters) are common in soy products.

So, what's the take-home?

Here's my take: There's no way to know how many environmental chemicals we're exposed to on a daily basis. Some estimate that there are as many as 80,000 chemicals in the environment, most of which have not been studied and are not regulated by the EPA. There's also no way to know for sure how many of these may turn out to have a link to hormone disruption. Emerging evidence -- like the current study -- suggests that there may be more of a connection than anyone previously thought.

What to do, what to do?

I'd suggest avoiding as many chemicals as you can. Stick with cooking utensils that haven't been treated. (Plain old cast iron pans are great!) Avoid plastics when you can. Avoid foods with tons of unpronounceable ingredients. If you can afford it, buy organic food or at the very least wash your produce thoroughly. Eat grass-fed meat if you eat meat (that's also hormone and steroid free). Follow Michael Pollan's "Food Rules."

It's hard enough to lose weight and keep it off. We don't need to make it harder by playing Russian roulette with our metabolism. Avoiding chemicals, processed foods and pesticides may not guarantee an easier time losing weight, but as my grandmother used to say, it sure couldn't hurt.

For more cutting edge information on health, nutrition, weight-loss and supplements, visit Dr. Jonny's Web site.

Jonny Bowden, author, nutritionist and weight loss coach cuts through all the misconceptions about diet and fitness to help you transform your body, your health and your life.