Twenty-one of 52 patients with regional enteritis had low serum zinc concentrations on initial testing. Fourteen of 31 patients followed longitudinally had low serum zinc concentrations. Two patients are presented as case reports who developed acrodermatitis skin lesions that responded to zinc therapy. Hypogonadism, growth retardation, and abnormalities in taste were frequent complications in Crohn's patients with low serum zinc levels. Certain complications of regional enteritis may be due, in part, to zinc deficiency.