Maintaining weight loss depends on the brain
New research shows that maintaining weight loss depends on how the brain responds to food. Behavioral changes associated with dieting are important to avoid regaining lost weight. The new study shows that differences in brain activity exist between people who are able to maintain weight loss, and those who put weight back on after dieting.
Findings published in the American Journal of Clinical Nutrition suggest that learning how to respond differently to food is important for maintaining weight loss.
Using functional magnetic resource imaging (fMRI), researchers were able to observe brain response in individuals able to maintain weight loss, comparing to obese and normal weight participants. When individuals able to keep weight off were shown pictures of food, images showed activation in the area of the brain responsible for behavioral control and visual attention.
Lead author Jeanne McCaffery, PhD, of The Miriam Hospital's Weight Control and Diabetes Research Center says, "Our findings shed some light on the biological factors that may contribute to weight loss maintenance. They also provide an intriguing complement to previous behavioral studies that suggest people who have maintained a long-term weight loss monitor their food intake closely and exhibit restraint in their food choices."
Maintaining weight loss through behavioral changes is an important part of successful diet programs to prevent discouragement with regaining weight. Most people do put weight back on after dieting, making obesity treatment challenging.
The current study used fMRI after study participants fasted four hours, ensuring they would be hungry. When shown pictures of a variety of low calorie, and high calorie food, in addition to non-food photos, the researchers documented the response in the brain. Included were pictures of salads, fruits, vegetables, French fries, ice cream, hot dogs, and shrubs, rocks and flowers. The findings showed that successful weight loss maintainers had increased activity in the left superior frontal region and right middle temporal region of the brain – areas related to inhibition and control.
The study shows that how our brain responds to food can be an important factor for maintaining weight loss. The researchers are not sure if brain responses are intrinsic among individuals who cannot maintain weight loss, or if they can be changed. The answer will require more studies.
Am J Clin Nutr: doi:10.3945/ajcn.2009.27924