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Teens who stay up late may end up gaining more weight as they become adults, researchers found when they followed 3,342 teenagers for 15 years. For every extra hour teens stayed up on weeknights, their body mass index (a ratio of weight to height) rose. The increase translated to a 13-pound weight gain for a 5-foot-5-inch teen who started the study weighing 120 pounds. The link wasn’t related to total sleep duration, exercise, or time spent viewing computer or television screens. Instead, those who stayed up later consumed more fast food. A possible remedy: Convince your teens to turn in earlier and give them healthful snacks instead of junk food.
Source: Sleep, published online Oct. 1, 2015