In the gut, there are harmful bacteria associated with disease as well as beneficial bacteria that are essential for daily bodily functions. One of the challenges is to kill harmful bacteria while allowing the beneficial bacteria to thrive.
Alcohol is known to be able to kill bacteria, so one would assume consumption of alcohol would kill both the harmful and beneficial bacteria in the gut. Research has shown that wine and other alcohol can help kill harmful bacteria in your stomach before it reaches your intestine, such as Salmonella and norovirus. In fact, drinking in moderation could help boost the number of beneficial bacteria in your microbiome.