Effects of Physical Activity and Sedentary Behaviour on Brain Response to High‐Calorie Food Cues in Young Adults

Physical activity is known to be an effective method of weight management, due to increased burning of calories. However, this study published in Obesity, found that beyond the calorific effect, there is also a physiological change in the brain in areas associated with reward.

For this study, 22 lean and 18 obese people were selected and their activity levels assessed. Looking at levels of moderate to vigorous physical activity (MVPA), and levels of sedentary behaviour (SB). Next, they ingested some glucose and underwent an fMRI brain scan, and while in the scanner, they were shown images of high-calorie foods, alongside inanimate objects. The researchers looked at 10 regions of the brain known to be responsive to visual food cues. What they found is that those who engaged in MVPA had lower responses to the food cues, and those who engaged in SB, had higher responses. This was true of the healthy weight individuals, and particularly true amongst the obese participants.

The potential mechanism through which physical activity suppresses responses to food cues is still unclear, however what is clear is that reducing SB and increasing MVPA can have positive effects on regions of the brain associated with food perception. Future studies on the underlying mediators of the effects of physical activity on the brain’s response to unhealthy food cues, may provide an interesting new approach to treating obesity.