Every day we inhale, ingest, and absorb chemicals via our skin that can interfere with how we process calories—in certain conditions and quantities, they can direct our bodies to create more fat cells and send our hunger hormones into overdrive. "Ubiquitous chemicals, like phthalates and bisphenol A (BPA), are present in sufficient doses where they may meet these threshold conditions," says Felix Grün of the University of California, Irvine, where a landmark 2006 study coined a name for these new chemical enemies in the war against weight gain: obesogens. So where are these bad boys—and is there any way to avoid them? Read on.

OBESOGEN SOURCE THREAT LEVEL* HOW THEY ATTACK HOW TO AVOID THEM

New car smell
6
Any of 275 chemicals, many of them obesogens, could be wafting around the interiors of new cars, ready to be inhaled. They will linger at higher than acceptable levels for up to six months. Leave your car in the sun with the windows down as often as possible—the heat will release the obesogens into the atmosphere—and place a box of baking soda in the car to absorb the chemicals during those first six months.

Antibacterial soaps and hand sanitizers
6
If you take a Howard Hughes approach to germs and obsessively scrub your hands with sanitizers and special soaps, beware—you may be rubbing a whole load of triclosan, a big, bad obesogen, into your skin. Choose hand sanitizers made from ethyl alcohol, not triclosan. Skip antibacterial soaps altogether—they are no more effective than regular soaps in eradicating germs.

Shower curtains
7
Curtains made from PVC release as many as 108 chemicals into the air, including dozens of obesogens. The heat from a hot shower may accelerate the rate of this release. Choose curtains made from ethylene vinyl acetate (EVA) or polyethylene vinyl acetate (PEVA).

Teflon cookware
7
Teflon is made from a cocktail of perfluorochemicals that not only impart stick-resistant properties to cookware but can also disrupt your metabolism. Use cast-iron or stainless-steel pots and pans, and stock up on grass-fed butter and sunflower oil.

Personal care products
9
You're most likely coating yourself in phthalates every time you use fragranced shampoo, lotion, or cologne. Blood tests show a dramatic drop in levels when fragrance is avoided. If you absolutely can't give up the scent, save it for your favorite cologne—otherwise, stick to fragrance-free body products.

Plastic bottles
9
One week of drinking from certain plastic water bottles can result in a 70 percent increase in levels of the heavy-hitting obesogen BPA. Skip bottles with the recycling number 7 on the bottom—numbers 1, 2, 4, and 5 are generally regarded as safe.

Cash register receipts
10
It takes only 10 seconds for the BPA that coats thermal paper to transfer to the skin. In one study, the act of crumpling a receipt was shown to be the most efficient method of moving the obesogen into the body. Use bank-card and credit-card statements as proof of purchase, and if your work involves handling receipts, wear gloves.

1 = lowest, 10 = highest


• • •

One Final Note: Beware the Pizza Box
Some recycled-cardboard pizza boxes contain high levels of the obesogen diisobutyl phthalate. And that little piece of grease-repelling paper that's put underneath the pizza to protect the cardboard? It's basically a PFC sheet. If you must bring home a pizza, at least ask them to skip the paper.



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