Food is addictive: A study
– Reported, June 29 2013
Drug addiction and food addiction are similar, a new study has found.
Food could be as addictive as class-A drug heroin and nicotine in cigarettes, claims a new study. Researchers have found substance abuse and food with a high glycaemic index – such as white bread and potatoes – may trigger the same brain mechanism tied to addiction. Eating highly processed carbohydrates can cause excess hunger and stimulate brain regions involved in reward and cravings, according to the study.
The findings suggest that limiting ‘high-glycaemic index’ foods could help obese people avoid overeating. The study, published in the American Journal of Clinical Nutrition, investigated how food intake is regulated by dopamine-containing pleasure centres in the brain. Study leader Dr David Ludwig, of Boston Childrens Hospital in the United States, said: ‘Beyond reward and craving, this part of the brain is also linked to substance abuse and dependence, which raises the question as to whether certain foods might be addictive.’
To examine the link, researchers measured blood glucose levels and hunger, while also using MRI scanning to observe brain activity during the crucial four-hour period after a meal, which influences eating behaviour at the next meal. Evaluating patients in such a time frame is one novel aspect of the study, whereas previous studies have evaluated patients with an MRI soon after eating.
Twelve overweight or obese men ate test meals designed as milkshakes with the same calories, taste and sweetness. The two milkshakes were essentially the same; the only difference was that one contained rapidly digesting – high-glycaemic index – carbohydrates, and the other slowly digesting – low-glycaemic index – carbs. After the participants consumed the high-glycaemic index milkshake, they experienced an initial surge in blood sugar levels, followed by sharp crash four hours later.
This decrease in blood glucose was associated with excessive hunger and intense activation of the nucleus accumbens, a critical brain region involved in addictive behaviour. revious studies of food addiction have compared patient reactions to drastically different types of foods, such as high-calorie cheesecake versus boiled vegetables. Another novel aspect of the new study is how a specific dietary factor that is distinct from calories or sweetness, could alter brain function and promote overeating.
Dr Ludwig said: ‘These findings suggest that limiting high-glycaemic index carbohydrates like white bread and potatoes could help obese individuals reduce cravings and control the urge to overeat.’ Though the concept of food addiction remains controversial, the findings suggest that more interventional and observational studies be done.
Dr Ludwig said additional research will hopefully inform clinicians about the subjective experience of food addiction, and how they can potentially treat obese patients and regulate