Kathy Del Tonto (far right) participates in a class that teaches school cafeteria workers how to prepare meals from scratch. LiveWell Colorado hide caption

itoggle caption LiveWell Colorado

An overweight child reads her part during a skit that was in a 2010 program promoting healthy lifestyles sponsored by Children's Hospital near Denver. John Moore/Getty Images hide caption

itoggle caption John Moore/Getty Images

When they eat out at a restaurant, kids consume more calories than they do at home. Here, members of the Long Island Gulls hockey team enjoy a lunch at TGI Friday's back in 2007 in Marlborough, Mass. Bruce Bennett/Getty Images hide caption

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Canned food is a source of BPA exposure, but researchers aren't sure whether it causes childhood obesity. Above, the soup isle at a grocery store in Washington, D.C. Maggie Starbard/NPR hide caption

itoggle caption Maggie Starbard/NPR

Childhood obesity is on the rise in many countries and overuse of antibiotics is now on the radar as a possible factor in the epidemic. Here 18-month-old twins are weighed in a nutritionist's office in Colombia. Raul Arboleda/AFP/Getty Images hide caption

itoggle caption Raul Arboleda/AFP/Getty Images

Karlton Hill, 15, was diagnosed with diabetes when he was 12. He works hard to manage the disease: He jogs and does pushups every day; he takes metformin is very careful about what he eats. Leslie Capo/LSU Health Sciences Center hide caption

itoggle caption Leslie Capo/LSU Health Sciences Center

Moms and their kids protest a proposed ban on homemade food at bake sales in New York City schools at a rally near City Hall in 2010. One sign read, "I wanna get obese on my terms. No junk food." edenpictures/Flickr hide caption

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People stroll down a street in Montpelier, Vt., last summer. In 1995, 13.4 percent of Vermonters were considered obese. The figure climbed to 23.5 percent in 2011. The latest national data suggest the obesity epidemic has plateaued, however. Toby Talbot/AP hide caption

itoggle caption Toby Talbot/AP

Alexandria Johnson got involved with the Anderson Monarchs soccer team when her mother was looking for an affordable way to keep her active. Todd Vachon/WHYY hide caption

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