In Brief: Snacks in Your Brain

How much you snack may be related to an area of the brain related to reward and pleasure more than how hungry you are, suggests a small new brain-imaging study.

In the study, 25 women first completed a questionnaire that measured how hungry they were. The women had not eaten at least six hours prior to the study.

The women were then shown pictures of non-food items and a variety of different foods. As they were seeing the images, scientists used MRI scanning to look at the activity of a brain region called the nucleus accumbens. This area is associated with motivation and reward.

After an hour, the women rated the food images for desirability and again rated their levels of hunger and food craving. Then everyone was offered the same amount of potato chips. Afterwards, the women rated the food images for desirability and again rated their levels of hunger and food craving.

Brain responses to the foods varied substantially among the individuals. But overall, the study found that it was the brain activity to the food images that determined how many potato chips participants ate, as opposed to the reported feelings of hunger or how much they liked the chips. More research is needed to answer many questions, including whether brain response and levels of self-control are learned or inherited.

Source: Natalia S. Lawrence, Elanor C. Hinton, John A. Parkinson, Andrew D. Lawrence. Nucleus accumbens response to food cues predicts subsequent snack consumption in women and increased body mass index in those with reduced self-control. NeuroImage, 2012.