There's no denying that an overload of sugar, fat, and calories fuels childhood obesity. But there's more to the story than too many potato chips and a bad video game habit. Your child's shampoo could be in play, too. "Diet and physical activity are still the leading causes of childhood obesity, this study lends evidence to the notion that we need to consider environmental contributions as well," explains Leonardo Trasande, MD, professor of pediatrics at New York University School of Medicine. "When we think of disparities in childhood obesity, we also need to think of disparities in environmental exposures."

The fat-promoting chemicals in question in Dr. Trasande's latest research are called phthalates, plasticizing chemicals used in man-made fragrances. This type of chemical is a criminal in the health world, with studies linking exposure to phthalates to everything from certain cancers and obesity to type 2 diabetes, allergies, and asthma. Still, it's perfectly legal for companies to add phthalates to products we come in contact with every day.

Dr. Trasande's new study appears in the journal Environmental Health Perspectives and finds a connection between childhood obesity and a common chemical found in childhood shampoos, lotions, soaps, and other everyday products. Specifically, his study found the urine samples from black children contained higher levels of fat-promoting phthalates, possibly because they're exposed to more of these fragrance-containing personal care products. It's not yet clear if black children

Looking at data collected from about 2,900 children, researchers found black children with a roughly three-fold increase in phthalate breakdown materials in the urine were more than 20 percent more likely to be overweight or obese.

Regardless of age or race, the mounting evidence linking phthalates to a wide array of health problems makes it a smart choice to evict these chemicals from your family's daily routine. Here's how to do it.

Do the database. To rate the safety of the current personal care products in your home—children and adult products—visit Environmental Working Group's Skin Deep Database. The nonprofit collects scientific data on ingredients and then rates overall products 0 (the safest) to 10 (the most toxic).

Forget fragrances. Avoiding synthetic fragrances is a fast-and-easy way to lower your exposure to fat-promoting phthalates chemicals. On personal care products, things listed as "fragrance" or "parfum" likely contain phthalates. Skip chemical air fresheners, gels, and scented candles, too. If there's a funky smell in your home, find the source, clean it up, and if you'd like, set a small bowl of white vinegar somewhere away from children and pets—it'll help absorb the lingering foul odors.

Phase out plastics. Phthalates also hide out in vinyl products, so trade in your vinyl shower curtain for a cotton or hemp version, and avoid children's products with shiny plastic decals, like book bags containing vinyl.

Clean smarter. Beware of household cleaners on your stores shelves. Even the green ones. Chemical analysis has uncovered phthalates and even cancer-causers in many everyday cleaning products. Many contain fake phthalate-containing fragrances but they don't have to list it on the label. To protect your family, make your own green cleaning products using white vinegar, baking soda, and simple ingredients.