Craving is caused by natural chemicals produced in the brain region called neostriatum, according to new research published in Current Biology. These chemicals, named enkephalin, surge when eating palatable food, increasing the subject’s desire to eat more.
‘This means that the brain has more extensive systems to make individuals want to over-consume rewards than previously thought,’ said co-author Alexandra DiFeliceantonio. ‘It may be one reason why overconsumption is a problem today.’
The findings are based on experiments with rats. The researchers stimulated the rats’ nestriatum and gave them access to unlimited amounts of M&M’s. They confirmed that this area of the brain is linked to craving; moreover, they found that it was the release of enkephalin what boosted the desire to eat more.
‘The same brain area we tested here is active when obese people see foods and when drug addicts see drug scenes,’ said DiFeliceantonio. ‘It seems likely that our enkephalin findings in rats mean that this neurotransmitter may drive some forms of overconsumption and addiction in people.’
Alexandra G. DiFeliceantonio, Omar S. Mabrouk, Robert T. Kennedy, & Kent C. Berridge (2012). Enkephalin Surges in Dorsal Neostriatum as a Signal to Eat Current Biology DOI: 10.1016/j.cub.2012.08.014