Sweet Pleasure: Calories Register Reward Independent of Taste

That the brain has the ability to appreciate calories hedonistically without input from the tongue is a momentous report. A new study, using mice incapable of tasting sweetness, determined that the brain's pleasure system is activated when sugar is consumed independent of taste.

When the mice consumed sugar -whether they could taste it or not- dopamine levels increased suggesting that the mice were experiencing pleasure. When given a choice, taste deficient mice like normal mice selected the sipper containing a sugar solution over water. But when artificial sweetener was substituted, the “sweet blind” mice showed no bottle preference or change in dopamine levels indicating that the feel good effect was due to the calories.

Interestingly, mice with intact sweet taste did not have a greater pleasure effect from sugar than the artificial sweetener. So does taste trump calories? The authors imply that it might not and speculate that obesity and overeating may involve this calorie sensing sweet pleasure.

. de Araujo IE, Oliveira-Maia AJ, Sotnikova TD, Gainetdinov RR, Caron MG, Nicolelis MA, Simon SA. Food reward in the absence of taste receptor signaling.
Neuron. 2008 Mar 27;57(6):930-41