Chocolate's effect on the brain is similar to that of opium says a new study.
Researchers at the University of Michigan found that a natural brain chemical called enkephalin surged while rats snacked on M&M chocolate candies.
Enkephalin is an endorphin with similar characterisitics to heroin.
It is believed that this chemical may be responsible for binge-eating in people as well as drug addiction, said the Daily Mail.
In the study with rats, a brain area known to release enkephalin was stimulated during feeding times.
It was shown that with the release of enkephalin, the animals ate double their normal share of food, reported NBC.
More from GlobalPost: MasterCard for addicts, alcoholics prevents frivolous purchases
"‘This (study) means that the brain has more extensive systems to make individuals over-consume rewards than previously thought," said study author Alexandra DiFeliceantonio, of the University of Michigan, reported IANS.
"The same brain area tested here is active when obese people see foods and when drug addicts see drug scenes."
The findings bring researchers closer to understanding what drives addiction in the brain and how to stop it.
The study was published in the journal Current Biology.