Scientists believe they have found (one of) the reason(s) for the cyclical binge eating-dieting sequence that so many people seem to find themselves in when trying to lose weight. The team from Johns Hopkins University in Baltimore, MD believe the root of the problem lies with opioid receptors in the brain. Opioids are chemicals employed by the body for increasing pain tolerance and inducing sedation, amongst other duties. Their effects can produce a feeling of euphoria by binding to the opioid receptor, which is how illegal narcotics such as heroin work (and is also where the term ‘opiate’ originates). Natural opioids were once believed to be the reason for the “runner’s high” associated with strenuous exercise, but more recent research seems to indicate it may be from the endocannabinoid, anandamide, or possibly even brain neurochemicals such as dopamine or phenethylamine. What the scientists found was that continuous binge eating, focusing on high fat and high sugar foods, altered the expression of the opioid receptors in the part of the brain that controls food intake. It is possible that the feel-good effect from the binge is something that the person wants to recreate, thereby leading to further binges and possibly the development of an eating disorder.
Source: N.T. BelloCorresponding F. Casseusa, M.T. Chuanga, B.A. Mitchella, Z.W. Patinkina, P. Singha and T.H. Morana. Continuous or binge access to sweet-fat food reduces mu-opioid receptor mRNA expression in the nucleus of the solitary tract in female rats. Appetite Volume 52, Issue 3, June 2009, Page 819.