title: Absorption of stable70 Zn in healthy young men in relation to zinc intake.
abstract: Zinc absorption was measured in two groups of four healthy young men using the method of stable tracer isotope neutron activation analysis. All absorption measurements were made using a test dose of ZnCl2 in subjects who participated in an overnight fast and also in subjects from whom food was withheld for 5 h after ingestion of tracer. In one group of experimental subjects, dietary zinc intake was held constant (approximately 15 mg/day), and three different test doses of the tracer were administered at weekly intervals. Fractional absorption was 81% from a 4.52-mg dose, 67% from a 6.47 mg dose and 61% for a 24.52-mg dose. In the other group of subjects, dietary zinc was reduced from approximately 15 mg to less than 2 mg/day. This was accompanied by a significant increase in fractional zinc absorption of a fixed tracer zinc dose (1.19 mg), from 81 to 92%. This increase, which occurred within 6 days, was also measurable when the tracer zinc dose was increased to 4.76 mg. These data indicate that there is a significant effect of the dose level of stable zinc isotope on its fractional absorption. They also demonstrate that a restriction in dietary zinc intake results in a prompt increase in the absorption of a fixed pulse dose of zinc in healthy young men.
mesh_terms: D000328:Adult; D004032:Diet; D005243:Feces / Q000032:analysis; D006801:Humans; D007408:Intestinal Absorption; D008297:Male; D009501:Neutron Activation Analysis; D015032:Zinc / Q000097:blood / Q000378:metabolism* / Q000652:urine; D015033:Zinc Isotopes
chemical_list: D015033:Zinc Isotopes; D015032:Zinc