The recognition of potentially noxious physiological substances in the intestinal milieu, prompted the use of an "elemental" semi-hydrolysed formula diet in the prophylaxis of experimental acute ischemic enteropathy. An elemental diet protects the intestinal mucosa of rodents from radiation injury and facilitates mucosal healing. Clinical trials have shown the benefits of this form of treatment in the prevention of acute radiation enteritis and therapy of delayed enteropathy and Crohn's disease.