Ed Gribbin, head of Alvanon, says spandex is a "democratic" fiber because it morphs to the body as opposed to limiting it. Marisa Penaloza/NPR hide caption

itoggle caption Marisa Penaloza/NPR

One recent study found that people were able to burn up an extra 450 calories a day with one hour of moderate exercise. That can include walking briskly, biking or swimming.

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itoggle caption iStockphoto.com

To encourage healthy choices, Dow's corporate cafeteria features color-coded utensils. Healthy foods like broccoli, spinach and beets have green handles. Yellow handles mean caution, and red is for temptations like bacon bits and high-fat dressing.

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itoggle caption Jennifer Ludden /NPR

This office chair was custom-built by a company called ErgoGenesis for a client who exceeded the 600-pound limit of its other chairs. It cost $1,800.

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itoggle caption Courtesy of ErgoGenesis

Ryan Van Duzer, an outdoor enthusiast who has starred in reality TV adventure shows, visits Colorado schools to talk about how working out can be entertainment. He says he often leaves frustrated after kids tell him about staying inside playing video games. Kirk Siegler for NPR hide caption

itoggle caption Kirk Siegler for NPR

Before getting bariatric surgery, Los Angeles DJ Big Boy posed for a photo promoting his radio station, Power 106. He weighed more than 500 pounds. Courtesy of Power 106 FM hide caption

itoggle caption Courtesy of Power 106 FM

In the CBS series Mike & Molly, Molly Flynn (Melissa McCarthy) and Mike Biggs (Billy Gardell) show a healthy intimate relationship. While many obese people lead happy and healthy sex lives, therapists are seeing more obese people who say their intimate lives are suffering because of their weight. Richard Cartwright/AP hide caption

itoggle caption Richard Cartwright/AP

Valerie Moore's weight and poor eating habits caught up with her two years ago, when she had a stroke at age 26. Dave Anderson Photography hide caption

itoggle caption Dave Anderson Photography

Jackie Gleason (right) played Ralph Kramden — a bumbling but loveable overweight husband — in the 1950s sitcom The Honeymooners. Audrey Meadows co-starred as his wife, Alice. Paramount Pictures/Getty Images hide caption

itoggle caption Paramount Pictures/Getty Images

As part of her exercise routine, Curtis starts most mornings walking a gaggle of neighborhood toddlers to their day care. Tovia Smith/NPR hide caption

itoggle caption Tovia Smith/NPR

Dr. David Gilder gives Sally Johnson a checkup at the Mallory Community Health Center in Tchula, Miss. Dave Anderson/Oxford American hide caption

itoggle caption Dave Anderson/Oxford American