While living on her own in college, 5’4″ Hannah Casey began gaining weight due to stress eating. “I would buy a box of extra-butter popcorn and eat all six bags in one sitting,” she says. Yo-yo diets made things worse: “I became the queen of fads and quick fixes. If I read that drinking grapefruit juice for a week would help you lose a few pounds, then I did it.” By January 2011, Hannah’s scale hit 248 pounds, and she suffered from joint pain, high blood pressure, and digestive issues.