The contribution of plant foods to the vitamin A supply of lactating women in Vietnam: a randomized controlled trial

Abstract

Background: More information is needed on the efficacy of carotenoids from plant foods in improving vitamin A status. Objective: We aimed to quantify the efficacy of provitamin A-rich vegetables and fruit in improving vitamin A status. Design: Breastfeeding women in 9 rural communes in Vietnam were randomly allocated to 1 of 4 groups: the vegetable group (n ҃ 73), which ingested 5.6 mg ␤-carotene/d from green leafy vegetables; the fruit group (n ҃ 69), which ingested 4.8 mg ␤-carotene/d from orange or yellow fruit; the retinol-rich group (n ҃ 70), which ingested 610 g retinol/d from animal foods and 0.6 mg ␤-carotene/d; and the control group (n ҃ 68), which ingested 0.4 mg ␤-carotene/d. Meals of groups 1, 2, and 4 contained 30 g retinol/d. Lunch and dinner were provided 6 d/wk for 10 wk. Results: Mean (95% CI) changes in serum retinol concentrations of the vegetable, fruit, retinol-rich, and control groups were 0.09 (0.03, 0.16), 0.13 (0.07, 0.19), 0.25 (0.17, 0.33), and 0.00 (Ҁ0.06, 0.06) mol/L, respectively. Mean (95% CI) changes in breast-milk retinol concentrations were 0.15 (0.04, 0.27), 0.15 (0.02, 0.28), 0.48 (0.32, 0.64), and Ҁ0.06 (Ҁ0.21, 0.09) mol/L, respectively. According to these findings, the equivalent of 1 g retinol would be 12 g ␤-carotene (95% CI: 8, 22 g) for fruit and 28 g ␤-carotene (17, 84 g) for green leafy vegetables. Thus, apparent mean vitamin A activity of carotenoids in fruit and in leafy vegetables was 50% (95% CI: 27%, 75%) and 21% (7%, 35%), respectively, of that assumed. Conclusion:The bioavailability of carotenoids from vegetables and fruit is less than previously assumed.Am J Clin Nutr 2007;85: 1112-20.

Plasma and dietary carotenoids and vitamins A, C and E and risk of colon and rectal cancer in the European Prospective Investigation into Cancer and Nutrition

“…26 Vitamin C was determined in 250 lL plasma by reversed phase chromatography using fluorescence detection. 27 Case-control sets were assayed in the same batch to minimize batch-to-batch variations.…”

“…BMI was selected instead of waist circumference, because BMI had no missing values. Participants were cross-classified according to quartiles of intake of vitamins and carotenoids and categories of smoking status (current, former and never smokers), alcohol consumption [low (0-3 g/day for women and 0-6 g/day for men), moderate (3-12 g/ day for women and 6-24 g/day for men) and high (>12 g/ day for women and >24 g/day for men)], BMI (<25, [25][26][27][28][29][30] and >30 kg/m 2 ) and physical activity (inactive, moderately inactive, moderately active, active participants). Deviation from multiplicative interaction was tested by likelihood ratio tests comparing models including multiplicative interaction terms with models without interaction terms.…”

Vitamin A intake and infection are associated with plasma retinol among pre-school children in rural Zambia

“…Vitamin A retinol activity equivalents (RAE) were used, where the retinol equivalency is assumed to be 12:1 for b-carotene and 24:1 for a-carotene and bcryptoxanthin (17) . However, it has been suggested that the retinol equivalency of provitamin A carotenoids from green and yellow vegetables is as high as 26-28:1, while from fruits it is 12:1 (18)(19)(20) . We thus calculated 'alternative vitamin A RAE' intake data assuming that provitamin A from green and yellow vegetables had a retinol equivalency of 26:1 and that from fruits, orange vegetables and orange and yellow roots had a retinol equivalency of 12:1.…”

Aplikasi Bioinformatik Untuk Studi Genetik Jagung Pro Vitamin-A

“…Jagung provit-A mengandung vitamin A (betakaroten) 8-15 μg/g, lebih tinggi dibanding jagung biasa yang hanya mengandung betakaroten 1,0 μg/g. Betakaroten dapat mencegah defisiensi vitamin A, meningkatkan daya tahan tubuh, membantu pertumbuhan gigi, mencegah buta dini, dan meningkatkan nafsu makan (Science Daily, 2008;Nutra, 2008;Cong Khan et al, 2007;Bwibo dan Neumann, 2003).…”