A brain scan study suggests it may be possible to train your brain to prefer healthy low-calorie foods over unhealthy higher-calorie foods, reversing the addictive power of unhealthy food.
"We don't start out in life loving French fries and hating, for example, whole wheat pasta," said Susan B. Roberts, Ph.D., a professor at the Friedman School of Nutrition Science and Policy at Tufts University and an adjunct professor of psychiatry at Tufts University School of Medicine. "This conditioning happens over time in response to eating -- repeatedly! -- what is out there in the toxic food environment."
Scientists have long suspected that, once unhealthy food addiction circuits are established, they may be hard or impossible to reverse, subjecting people who have gained weight to a lifetime of unhealthy food cravings and temptation.
To find out whether the brain can be re-trained to support healthy food choices, Roberts and colleagues studied the reward system in 13 overweight and obese men and women, 8 of whom were participants in a new weight loss program designed by Tufts University researchers and 5 who were in a control group and were not enrolled in the program.
The study is published in the journal Nutrition & Diabetes.
Both groups underwent magnetic resonance imaging (MRI) brain scans at the beginning and end of a 6-month period. Among those who participated in the weight loss program, the brain scans revealed changes in areas of the brain reward center associated with learning and addiction. After 6 months, this area had increased sensitivity to healthy, lower-calorie foods, indicating an increased reward and enjoyment of healthier food cues. The area also showed decreased sensitivity to the unhealthy higher-calorie foods.
"The weight loss program is specifically designed to change how people react to different foods, and our study shows those who participated in it had an increased desire for healthier foods along with a decreased preference for unhealthy foods, the combined effects of which are probably critical for sustainable weight control," said co-author Sai Krupa Das, Ph.D., an assistant professor at the Friedman School. "To the best of our knowledge this is the first demonstration of this important switch."
The authors hypothesize that several features of the weight loss program were important, including behavior change education and high-fiber, low glycemic menu plans.
"There is much more research to be done here, involving many more participants, long-term follow-up and investigating more areas of the brain," Roberts added. "But we are very encouraged that, the weight loss program appears to change what foods are tempting to people."