most common cause of yeast infections
Causes of Yeast Infection. The most common cause of yeast infections in men is the instability in the ratio of good bacteria to yeast, in the digestive system, which helps the yeast fungi flourish and spread throughout the body.
Report Abuse. Probably the most common cause is hormones causing bacterial fluctuations in the vaginal environment, which in turn allow an overgrowth of yeast. The second most common cause would probably be antibiotic use (because it kills off ALL the bacteria in your body-good AND bad).