Most people who go on diets soon gain back any lost weight, a UCLA study suggests.
Traci Mann, PhD, associate professor of psychology at UCLA, was teaching a seminar on the psychology of eating when she noticed something odd(奇怪的) about diet studies. Few of the studies followed up on dieters for more than six months. Even fewer followed dieters for a year or more.
Mann wondered what, in the long term, really happens when people go on diets. So she and her students tracked down 31 studies that, one way or another, had at least one year of follow-up data. They were interested in just one number: the percentage of dieters who, over time, gain back more weight than they lose.
"We found that the average percentage of people who gained back more weight than they lost on diets was 41%," Mann tells WebMD. "In each of the studies, a third to two thirds of thesubjectsgained back more weight than they lost. "
Does this mean that most of the people in the studies actually lost weight and kept it off? No, Mann says.
"This is actually bleaker(更不乐观的)than it seems-even though most people would find that 41%number to be pretty depressing(令人沮丧的)," she says. "We have strong reasons to feel that this number underrepresents the true number of participants who gained back more weight than they lost."
Mann and her colleagues report their findings in the April issue of American Psychologist.
