Myth buster

Notable faculty: Traci Mann, a psychology professor in the U’s College of Liberal Arts (CLA), translated her scientific research into an engaging, accessible book that debunks some of our most deeply held beliefs about dieting and obesity. 
The book: Secrets from the Eating Lab: The Science of Weight Loss, the Myth of Willpower, and Why You Should Never Diet Again 
Biggest finding: Diets don’t work. “People see their weight drop and give the diet credit,” says Mann, founder and director of the Health and Eating Lab in CLA’s Department of Psychology, “but then they blame themselves when they gain it back. They don’t realize that the weight coming back is a predictable, expected part of the process.” In a review of dozens of diet studies, Mann found that at the end of the study periods (which ranged from two to 10 years), dieters weighed just 2 pounds less, on average, than they had at the beginning. 
Why is that? There are several reasons:

  • When you restrict calories, your metabolism changes to allow you to survive on less. “That means that the number of calories you ate to lose weight eventually becomes too many calories to eat if you want to keep losing weight,” Mann writes in her book. 
  • Your hormones change when you’re dieting, making you feel less full.
  • Research has shown that people’s attention changes when they’re restricting calories. “You become preoccupied with thoughts of food, you’re more likely to notice food, and once you notice it, you have more trouble taking your attention away from it,” she says. 

How gifts from donors help: Financial support from the Engdahl Family Research Fund allowed Mann to study whether gradually reducing sugar in coffee was an effective way of reducing sugar intake. Participants who used the often-recommended method of gradually cutting back sugar reported that they liked their coffee less and less as they reduced sugar. A group that went “cold turkey” (using no sugar at all in their coffee) and received mindfulness training, however, was still choosing to drink coffee with no sugar six months after the study ended.

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