A new study shows that food addiction may be quite similar to drug addiction, neurologically speaking. For people who have struggled with compulsive eating and weight issues their whole lives, the results may not come as a surprise. The research is among the first to illustrate that the brains of "food-addicted" people respond to both the thought and action of eating food in very much the same way as the brains of drug addicts respond to drugs.

The participants were shown pictures of milkshakes or glasses of water while their brains were being scanned with MRI.

In the study, the researchers looked at 48 women who had taken part in a weight loss program. The women ranged from normal weight to obese. Each completed the Yale Food Addiction Scale (YFAS), a scale the team had designed previously and which uses questions similar to those that determine whether people may be addicted to alcohol or drugs. The YFAS helped the research team to measure how "food-addicted" each participant was.

The participants were shown pictures of milkshakes or glasses of water while their brains were being scanned with MRI. After a couple of seconds of thinking about the food, the women were asked to take a sip of either a milkshake or a solution designed to taste like saliva (this "flavor" was chosen instead of water since water’s distinct flavor can activate the taste centers of the brain).

When looking at the pictures of the milkshakes, the women who scored higher on the food addiction scale, no matter whether they were obese or normal weight, showed more activity in parts of the brain associated with reward. This is exactly what is found when studying people with other types of substance abuse problems.

When the women actually tasted the milkshakes, those with higher food addiction scores had less activity in brain areas that control inhibition and satiety. In other words, women who were more food-addicted may have less ability to control the eating behavior, or less capacity to be satiated by the food they eat. Again, the same pattern has also been seen in the brains of people with other types of substance abuse.

Lead author Ashley Gearhardt says in the study’s press release that this avenue of research is especially important since it may one day help us understand how food addiction works, not just in adults, but also in children, whose obesity rates have climbed alarmingly high in this country.

"Kids are in an especially dangerous position," Gearhardt said. "From an early age, they are exposed to addictive food, and we would like to look into how those foods affect their bodies and brains." Future research will no doubt look at how and when food addiction may develop in children and teens, and what may be done to help address and reverse it early on.

Gearhardt is a doctoral candidate at Yale University. The study was published in the April 4, 2011 online issue of Archives of General Psychiatry.