Question

Is it normal for an infant’s stool to be green?

Answer

Stool that is light green can be normal in breastfed infants. If the baby’s stool is dark green, it may be a sign of indigestion. When stool is acidic, the bile it contains is oxidized by air to become green. Bilirubin, a yellow pigment in bile, colors the stool yellow. After oxidation, bilirubin turns into biliverdin, causing the stool to appear green. When the excrement comes into contact with oxygen in the diaper, bilirubin oxidizes into biliverdin, making the surface of the stool green.