Evaluation of the newly proposed vitamin A supplementation regimen for postpartum mothers using stable carbon isotopes

The long-term goal of this project is to establish public health programs to improve the health of women and children globally by determining safe and effective methods to improve vitamin A status. By improving the vitamin A status of mothers and infants, mortality and morbidity of children will be reduced. The specific aims of this proposal are: - To determine the length of time mothers are protected against depletion after receiving either 400,000 IU of vitamin A in two doses of 200,000 IU 24 hours apart or one dose of 200,000 IU. The modified relative dose response (MRDR) test will be used at monthly intervals for 5 months post dosing to assess changes in vitamin A status. - To determine the degree of dilution in the vitamin A body pool after dosing women with either 200,000 or 400,000 IU of vitamin A using stable 13C2-retinol as a tracer. - To determine the difference in total vitamin A body reserves of women who received either 200,000 or 400,000 IU of vitamin A using the 13C2-retinol isotope dilution (13C2-RID) test. This proposal addresses the following hypothesis: In women who are given 400,000 IU of vitamin A, the length of protection from vitamin A depletion is increased but not doubled. A 400,000 IU dose dilutes the vitamin A pool more than 200,000 IU but not by 2:1 and a 400,000 IU dose increases the total body reserves of vitamin A over 200,000 IU but not by 2:1. (author)