Bob Harper on ‘Biggest Loser’ weight-loss controversy, intermittent fasting

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A recent study examined 14 contestants from the eighth season of “The Biggest Loser,” with startling results. Bob Harper, who was the trainer that season and now is host of the weight-loss reality competition, tells Savannah Guthrie, “You have to watch every single thing” after weight loss to avoid going back to the same weight. He also talks about the intermittent fasting trend.