Can we talk about friends for a sec? We hang with them, rely on them...and, occasionally, do shots with them. But what do you do when your friendships get in the way of your taking care of you? Many women are kicking these kinds of relationships to the curb: In the Edelman Health Barometer 2011 survey, analyzed exclusively for Glamour, 32 percent of women ages 20 to 39 said they spent less time with a pal because of his or her negative health habits. "After my friend developed an eating disorder, it became too hard to be around her," admits Caitlin, 24, of Ann Arbor, Michigan. "I tried to help her as best as I could, but her obsession started rubbing off on me. When I started seeing food through her eyes and dangerously restricting my own eating, I had to break things off." A little distance can be a smart move: Research shows that bad health behaviors can actually be contagious. Both eating disorders and obesity can spread through groups of friends, studies have found. It's also been shown that friends are the biggest influence on whether women, especially young women, smoke.