Junk food addicts show same brain activity as drug addicts

Indulging in food cravings could be more than just a matter of a weak will. After studying the brain activity of women presented with a chocolate milkshake, researchers in the US found that seeing the tempting dessert drink activated the same parts of the brain as a drug addict who sees cocaine.

The Yale University study - published online this week and due to appear in the August issue of Archives of General Psychiatry - found that higher food addiction scores correlated with greater activation in certain areas of the brain - the same areas that light up among people with a substance dependence.

Participants included 48 healthy young women ranging from lean to obese. They were presented with both a chocolate milkshake and a tasteless control solution. Milkshakes were chosen not only for their high fat and sugar content, but also because it allowed participants to keep still during head scans.

The implications of the study could be wide-ranging. One-third of American adults are obese and suffer from obesity-related diseases, researchers point out. Most obesity treatments fail and patients regain the weight within five years. But if certain foods are addictive, not only could that explain why some people can't lose weight, it could also change the dialogue on obesity and food advertising, the study suggests.

"If food cues take on enhanced motivational properties in a manner analogous to drug cues, efforts to change the current food environment may be critical to successful weight loss and prevention efforts," reads the study. "Ubiquitous food advertising and the availability of inexpensive palatable foods may make it extremely difficult to adhere to healthier food choices because the omnipresent food cues trigger the reward system."

Researchers from The Scripps Research Institute in Florida came to similar conclusions last year when they found that overconsumption of high-calorie foods can trigger addiction-like responses in the brain. The study, which used lab rats, could help in understanding obesity as a food addiction and in developing therapies for it, researchers said.

Though compulsive eaters can do little to avoid fast-food billboard ads around their city or commercials on TV, the Mayo Clinic offers advice on how to change the food environment at home. For example, keep less food at home than usual to avoid temptation. Keeping the house junk food-free also eliminates visual cues.

http://archpsyc.ama-assn.org/cgi/content/abstract/archgenpsychiatry.2011.32v1