Is food addictive? New study adds to the evidence

There is new evidence to support the hotly-debated notion that you can be addicted to food, much like people get addicted to cocaine or heroin. A new study finds cravings may be "hard-wired" into the brains of people who are overweight.

The research was presented Sunday at a conference of the European College of Neuropsychopharmacology.

For the study, an international group of researchers offered buffet-style food to 81 people -- 39 of them obese, and 42 of normal weight. After eating the food, the people were put into MRI brain scanners and shown photographs of the food, which should stimulate food cravings.

"The big finding here was that food cravings had a different effect on the brains of obese people versus people of normal weight," CBS News medical contributor Dr. Holly Phillips explained on "CBS This Morning." "So people who were obese saw a greater stimulation in areas of the brain that we call the 'reward center,' where it controls our behavior based on reward and stimulation, than people of a normal weight."

Three months later, the researchers measured the patients' Body Mass Index (BMI). They found that 11 percent of the weight gain in the obese people could be predicted by this brain behavior.

The findings suggest that the tendency to crave food may be hard-wired into the brains of overweight people. But Phillips cautions that comparing food addiction with drug addiction is controversial.

"Food addiction is not a recognized medical condition, whereas drug addiction is," she said. "Drug use causes neuronal changes in the brain that do not go away, and it changes the way the brain functions."

Despite the latest study, she noted, "We don't know if food does that yet. What we do know is both food and drugs can cause behaviors that are very similar to addiction -- the inability to cut down, continued use despite negative consequences, a sense of a loss of control -- so they clearly have some similarities."

Foods that tend to be most associated with cravings generally have a high glycemic index, containing high levels of sugar, fat and salt. "These are foods that have a very intense and fast effect on our blood sugar," Phillips said.

In the United States, more than 2 in 3 adults, and one-third of children, are considered to be overweight or obese, according to government statistics. People who are overweight or obese are at higher risk for type 2 diabetes, heart disease, high blood pressure, and other chronic health problems.

Phillips notes that the more researchers understand about what triggers obesity, the better they can treat it.