Hydrochloric acid (HCl) insufficiency can be complete (achlorhydria) or partial (hypochlorhydria) and intermittent. HCl plays an important part in the first digestive step, which if not completed properly can result in digestive problems all the way through the digestive tract. HCl does not digest food on its own, but creates an environment in which digestion begins. HCl is responsible for converting pepsinogen to pepsin, which begins breaking down proteins in the stomach. With limited HCl, pepsinogen is not converted to pepsin and protein digestion fails. A second action of HCl is to prevent infections, since most organisms that are ingested are destroyed by an adequately acid environment.