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ARS Home » Northeast Area » Boston, Massachusetts » Jean Mayer Human Nutrition Research Center On Aging » Research » Publications at this Location » Publication #207141
Title: Carotene-Rich Plant Foods Ingested With Minimal Dietary Fat Enhance The Total-Body Vitamin A Pool Size In Filipino Schoolchildren As Assessed By Stable-Isotope-Dilution Methodology

Author
item Ribaya-Mercado, Judy
item MARAMAG, CHERRY - NUTRITION CTR PHILIPPINES
item TENGCO, LORENA - NUTRITION CTR PHILIPPINES
item Dolnikowski, Gregory
item Blumberg, Jeffrey
item SOLON, FLORENTINO - NUTRITION CTR PHILIPPINES

Submitted to: The American Journal of Clinical Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/22/2006
Publication Date: 4/5/2007
Citation: Ribaya-Mercado, J., Maramag, C.C., Tengco, L.W., Dolnikowski, G., Blumberg, J., Solon, F. 2007. Carotene-Rich Plant Foods Ingested With Minimal Dietary Fat Enhance The Total-Body Vitamin A Pool Size In Filipino Schoolchildren As Assessed By Stable-Isotope-Dilution Methodology. American Journal of Clinical Nutrition. 85:1041-9.

Interpretive Summary: Stable isotope dilution methodology is a powerful tool for assessing vitamin A status and for evaluating the effectiveness of interventions aimed at improving the vitamin A status of populations. Based on data obtained with the use of other vitamin A assessment methods, the effectiveness of plant carotenoids in combating vitamin A deficiency has been questioned. Data from the present study indicate that it is possible to improve the total-body vitamin A pool size and restore low liver vitamin A concentrations to normal levels by eating sufficient carotene-rich yellow and green leafy vegetables with minimal dietary fat (2.4 g/meal). Thus, carotene-rich plant foods can effectively meet vitamin A needs. This finding is of public health importance especially in developing nations where health professionals and policymakers can promote the use of yellow and green leafy vegetables for combating vitamin A deficiency in vulnerable groups. In the US and other countries where school-feeding and other food programs are in place, the information is useful for formulating dietary guidelines for inclusion of carotene-rich vegetables and a small amount of dietary fat in meals.

Technical Abstract: Background: Strategies for improving vitamin A status of vulnerable populations are needed. Objective: We studied the influence of dietary fat amounts on the effectiveness of carotene-rich plant foods in improving vitamin A status. Design: Schoolchildren (9-12 y) were fed standardized meals 3 times/d, 5 d/wk, for 9 wk. The meals provided 4.2 mg/d of provitamin A carotenoids (mainly beta-carotene) from yellow and green leafy vegetables [carrots, pechay (bok choy), squash, and kangkong (swamp cabbage)] and either 7, 15 or 29 g fat/d (2.4, 5 or 10 g fat/meal) (Groups A, B and C; n=39, 39, and 38, respectively). Other self-selected foods eaten were recorded daily. At pre- and post-intervention, total-body vitamin A pool sizes and liver vitamin A concentrations were assessed by the deuterated-retinol-dilution method; serum retinol and carotenoid concentrations, by HPLC. Results: In the 3 study groups whose daily intakes of beta-carotene from study meals plus self-selected foods were 14 times usual intakes, and whose fat intakes were 0.9, 1.4, and 2.0 times usual intakes, similar increases were observed in serum mean beta-carotene (5-fold), alpha-carotene (19-fold), beta-cryptoxanthin (2-fold), total-body vitamin A pool size (2-fold), and liver vitamin A concentration (2-fold) after 9 wk; mean serum retinol concentration was unchanged. The overall prevalence of low liver vitamin A (<0.07 umol/g) decreased from 35% to 7%. Conclusions: Carotene-rich yellow and green leafy vegetables, when ingested with minimal fat, enhance serum carotenoids and the total-body vitamin A pool size, and can restore low liver vitamin A concentrations to normal levels.