Training the Brain to Prefer Healthy Foods

This might be a tough one to swallow, but it turns out that training your brain to crave vegetables instead of junk food can actually be done, according to a small study.

Scientists at the Jean Mayer USDA Human Nutrition Research Center on Aging (USDA HNR-CA) at Tufts University and at Massachusetts General Hospital have observed that we may be able to condition ourselves to want low-calorie foods instead of unhealthy, higher-calorie foods. Published online in the September edition of the journal Nutrition & Diabetes, the brain-scan study involving adult men and women suggests it is possible to reverse the addictive power of unhealthy foods while increasing our preference for healthy foods.

We don’t start out in life loving french fries and hating,
for example, whole wheat pasta,” said senior and co-corresponding author Susan B. Roberts, PhD, director of the Energy Metabolism Laboratory at the USDA HNRCA, who is also 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 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 retrained to support healthy food choices, Roberts and colleagues studied the brain’s reward system in 13 overweight and obese men and women, eight of whom were participants in a new weight loss program designed by Tufts researchers and five who were in a control group not enrolled in the program.

Both groups underwent 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 the brain’s reward center associated with learning and addiction. After 6 months, this area had increased sensitivity to healthy, lower-calorie foods, indicating an increased reward from them and more enjoyment of healthier food cues. The area also showed decreased sensitivity to 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 coauthor Sai Krupa Das, PhD, a scientist in the Energy Metabolism Laboratory at the USDA HNRCA and an assistant professor at the Friedman School. “To the best of our knowledge this is the first demonstration of this important switch.” The authors hypothesized 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.”