Chef Mike Isabella, who owns three restaurants in Washington, D.C., came up with the Fit for Hope weight loss challenge for his peers in the restaurant industry. Donald Bowers/Getty Images Entertainment hide caption

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CPAP masks have become much more comfortable than in years past, doctors say. But most of the time, they're probably not the first thing to try for sleep apnea. iStockphoto.com hide caption

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Differences in brain chemistry can affect an individual's likelihood of weight gain. Katherine Streeter for NPR hide caption

itoggle caption Katherine Streeter for NPR

"Studies show there is an association between regularly skipping breakfast and higher body mass index," an obesity researcher says. "But it does not necessarily represent cause and effect." iStockphoto.com hide caption

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Eating refined carbohydrates like bagels may stimulate brain regions involved in reward and cravings, research suggests. iStockphoto.com hide caption

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