The patient had an infection with Saccharomyces cerevisiae, Cordell says. So when he ate or drank a bunch of starch — a bagel, pasta or even a soda — the yeast fermented the sugars into ethanol, and he would get drunk. Essentially, he was brewing beer in his own gut. Cordell and McCarthy reported the case of "auto-brewery syndrome" a few months ago in the International Journal of Clinical Medicine.