Eating food can make us feel good
Evolution builds rewards into activities that are important for survival and reproduction, so the drive to eat when hungry is strong. Eating activates our brain’s reward system, which produces a good feeling via the neurotransmitter dopamine.
Recent studies suggest that some people who have genetically low levels of dopamine – and also show low activity in the food reward regions of the brain in imaging experiments – are especially prone to putting on weight. Their overeating could be an attempt to get a stronger response from their sluggish neurons or could stem from a higher than normal reward from eating: it feels so good you want more.
Both could be true. On one hand, there is evidence that obese people start out getting more reward from tasty snacks like chocolate ice cream. After they gain weight, their reward centres become less active when tasting the same treats. On the other hand, imaging studies also suggest that extreme hunger makes the reward centres respond more strongly to high-calorie foods (which, again, makes evolutionary sense).Lead image:
Illustration © Glen McBeth
- NBC News: Watch out for ‘food swings’ when hunger, anger collide
- Compensatory weight gain due to dopaminergic hypofunction: new evidence and own incidental observations (2008)