ORIGINAL RESEARCH COMMUNICATION
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
Judy D Ribaya-Mercado, Cherry C Maramag, Lorena W Tengco, Gregory G Dolnikowski, Jeffrey B Blumberg and Florentino S Solon
1 From the Jean Mayer US Department of Agriculture Human Nutrition Research Center at Tufts University, Boston, MA (JDR-M, GGD, and JBB), and the Nutrition Center of the Philippines, Taguig City, Philippines (CCM, LWT, and FSS)
Background:Strategies for improving the vitamin A status of vulnerable populations are needed.
Objective:We studied the influence of the amounts of dietary fat on the effectiveness of carotene-rich plant foods in improving vitamin A status.
Design:Schoolchildren aged 9–12 y were fed standardized meals 3 times/d, 5 d/wk, for 9 wk. The meals provided 4.2 mg provitamin A carotenoids/d (mainly ß-carotene) from yellow and green leafy vegetables [carrots, pechay (bok choy), squash, and kangkong (swamp cabbage)] and 7, 15, or 29 g fat/d (2.4, 5, or 10 g fat/meal) in groups A, B, and C (n = 39, 39, and 38, respectively). Other self-selected foods eaten were recorded daily. Before and after the intervention, total-body vitamin A pool sizes and liver vitamin A concentrations were measured with the deuterated-retinol-dilution method; serum retinol and carotenoid concentrations were measured by HPLC.
Results:Similar increases in mean serum ß-carotene (5-fold), -carotene (19-fold), and ß-cryptoxanthin (2-fold) concentrations; total-body vitamin A pool size (2-fold); and liver vitamin A (2-fold) concentrations were observed after 9 wk in the 3 study groups; mean serum retinol concentrations did not change significantly. The total daily ß-carotene intake from study meals plus self-selected foods was similar between the 3 groups and was 14 times the usual intake; total fat intake was 0.9, 1.4, or 2.0 times the usual intake in groups A, B, and C, respectively. The overall prevalence of low liver vitamin A (<0.07 µmol/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 concentrations.
Key Words: Vitamin A • deuterated-retinol dilution • stable-isotope dilution • retinol • plant carotenoids • ß-carotene • bioavailability • dietary fat • school-age children • Philippines
American Journal of Clinical Nutrition, Vol. 85, No. 4, 1041-1049, April 2007
© 2007 American Society for Nutrition 美國臨床營養學期刊(AJCN)
留言列表