Michelle Ethun '98 - Honors

The Correlation Between the Dietary Intake of the Fat-soluble, Antioxidant Vitamins Alpha-tocopherol and Retinol and Their Fasting Plasma Concentrations in Postmenopausal Women


Coronary heart disease (CHD) is the leading cause of death in older women with 500,000 dying annually. Postmenopausal women have a different relative risk for CHD due to the loss of ovarian function and cessation of menses. Recent epidemiological studies indicate that 1) an increase in α-tocopherol intake is associated with a decrease in the incidence of CHD in both men and women and 2) an increase in the plasma concentration of α-tocopherol is associated with a decreased susceptibility of LDL to oxidative modification. This study examined the dietary intake of α-tocopherol and retinol in a group of 32 postmenopausal women, and the correlation between dietary intake and plasma concentrations of these two vitamins. The 3-day diet records indicate that 66% of our population receives the RDA (8mg) of α-tocopherol and 93% receives the RDA (800 RE) of retinol. The mean intake is 38.43 mg TE for α-tocopherol and 1720 RE for retinol. Weak, positive correlations between intake and plasma concentrations for α-tocopherol and retinol were seen with correlations of r=0.326 and r=0.204 respectively. In general, this population consumes above average quantities of α-tocopherol and retinol (NHANES III). However, many are not meeting the RDA for α-tocopherol and only five are receiving 100 IU of α-tocopherol which is necessary to see antioxidant benefits. The low correlation coefficients between the intake and plasma levels suggest that dietary intake of α-tocopherol and retinol cannot accurately predict their plasma concentrations, nor do plasma levels of α-tocopherol and retinol reflect intake for the levels consumed by these women.

Faculty Mentor: Amy Olson, PhD, RD