Food addiction tendencies create strong responses in the brain similar to those of drugs and alcohol, according to a new study.
Previous studies have used functional MRI machines to look at the relationship between obesity and substance addictions but not at the link between people's food addiction tendencies and responses in the brain.
Researchers set up an experiment with 48 young women enrolled in a weight management program. Based on body mass index, subjects ranged from lean to obese.
After using the Yale Food Addiction Scale to assess subjects' food addiction tendencies, researchers placed them into a fMRI machine to measure blood flow in areas of their brains.
Each subject was presented with one of two photos: one of a chocolate milkshake, and another of a glass of water, for a couple of seconds.
Five seconds after exposure, subjects received small portions of a chocolate shake or a flavorless solution, depending on the image they just saw.
When subjects with higher food addiction tendencies viewed photos of a milkshake they displayed brain responses similar to what's seen in individuals with addictive behaviors toward drugs or alcohol. Areas of the brain associated with reward pathways such as the anterior cingulate cortex, orbitofrontal cortex and amygdala, showed more activity, the authors write.
Interestingly, they also discovered that body mass index did not necessarily predict levels of food addiction.
It also turns out that anticipation of food produces greater responses in the brain when compared to actually consuming the food. This might be why people with addictive eating behaviors overeat from not feeling satisfied.
One of the major drawbacks of the study, however, is its focus on women, not men. The authors admit more research is necessary to generalize these results to men and other age groups.
They also think the work will help understand biology's contributions to obesity, which affects nearly one third of adults in America, according to the CDC.