ANN ARBOR, Mich.---A new University of Michigan study finds that college women with roommates who weigh more than average gain less weight during their freshman year than women with slimmer roommates: half a pound versus 2.5 pounds.
That compares to the typical freshman weight gain of 2.5-to-6 pounds---much less than the mythical "Freshman 15."
"This finding seems counterintuitive, but there are some good explanations for why it may be happening," said Kandice Kapinos, an assistant research scientist at the U-M Institute for Social Research.
According to Kapinos, a labor and health economist, heavier roommates are more likely than average-weight women to diet. They also exercise more often and are more likely to use weight loss supplements and purchase college meal plans that limit access to food.
"It's not really the weight of your roommate that's important, but the behaviors your roommate engages in," Kapinos said. "These behaviors are what may really be 'contagious.'"
Kapinos conducted the study with Marquette University economist Olga Yakusheva. The study is the first to assess college weight gain using a natural experiment occurring on most college campuses in the United States---randomized roommate assignments.
"Previous studies have suggested that having an obese spouse, friend or sibling increases one's likelihood of becoming obese," Kapinos said. "But these relationships are obviously not random. People pick their friends and spouses, and they often select people who are similar to themselves. And even though we don't pick our siblings, we share a genetic inheritance and an early environment that may influence adult weight."
For the current study, which was presented this summer at the annual meeting of the American Society of Health Economists, the researchers assessed 144 female college students randomly assigned to share a living situation during their freshman year. At the start of the
|Contact: Diane Swanbrow|
University of Michigan