An article was recently published in PNAS that investigated the relationship between alcohol dependence and the microbiome. The authors had previously shown that alcohol-dependent people are at higher risk for a 'leaky gut', in which some molecules, such as bacterial metabolites, are passing through the GI tract into the bloodstream. Leaky guts cause an inflammatory response that leads to further health issues. In their new study, the authors investigated whether alcohol craving, and depression are associated with the gut microbiome, and suggest the possibility of targeting the microbiome as a therapeutic modality during alcoholism recovery.

The authors studied 60 alcohol dependent subjects who recently stopped drinking and measured their microbiome, leakiness of gut, and mood. They immediately discovered that the leakiness of the gut was associated with alcohol craving during withdrawal. The more leaky the gut, the more the subject craved alcohol, whereas patients with less leaky guts had less psychological addictions.

The authors also discovered that leakier guts were associated with microbiome dysbiosis, which included many bacteria associated with inflammatory bowel disease (IBD). Other studies have shown that similar dysbioses are associated with leaky guts in IBD patients, and in recovering alcoholics the dysbiosis can last long after cessation of drinking.

This study suggests that potential treatments for recovering alcoholics could include targeting the microbiome to bring it back to a more 'normal' state. This normal state will decrease the permeability of the gut (make it less leaky), and thus decrease the psychological addiction to alcohol.