Since human beings can barely absorb sorbitol (or lactulose) into their bloodstream, it is often used as a sweetening agent. It then appears on food labels as E420, and this explains why sugar-free cough candies, for example, always include the warning, “Excessive consumption may have a laxative effect.” Some studies have shown that sorbitol has a similar effect to lactulose, but causes fewer side effects overall (no unpleasant wind).
