Acute diet soda consumption alters brain responses to food cues in humans: A randomized, controlled, cross-over pilot...

Diet soda consumption has frequently been linked to obesity and its comorbidities in epidemiological studies. Whether this link is causal and a potential mechanism remains to be determined.

This randomized, cross-over, controlled pilot study sought to determine whether there may be changes in reward-related brain activations to visual food cues after acute consumption of diet soda versus regular soda or carbonated water using functional magnetic resonance imaging.

Diet soda as compared to carbonated water consumption increased activation of reward-related caudate to highly versus less desirable food cues. Diet soda as compared to regular soda increased reward-related insula and decreased activation of cognitive control-related dorsolateral prefrontal cortex to food cues versus non-food cues. No changes in ratings of hunger an hour after beverage consumption were observed.

These results may suggest a potential mechanism for diet soda to increase food palatability through activation of the reward system and suppression of inhibitory control that remains to be confirmed by future studies.