How Come the Day After I Drink Red Wine My Stool is Dark Green?
Red wine will darken your stool, some more than others. It is nothing to be alarmed about, it’s just natural coloring. Most foods have color that get digested, while red wine, and green food coloring if you’re been out for St Patrick’s Day, have color in them that don’t get digested.
The fact that yours is dark green instead of dark brown is a bit out of the ordinary. Light green stool is usually the result of a diet that consists of too much sugar, fruits and vegetables, and not enough grains and salt. Possibly your diet when you drink red wine is lacking in grains and salt, and heavy in fruits and sugars (isn’t that what wine is?).
If you’re concerned you should consult your doctor. More details can be determined with blood tests and other tests that only a doctor can perform.