BACKGROUND: It is important to understand the factors affecting strategies to improve the vitamin A status of populations. We reported previously that a 3-d deuterated-retinol-dilution (DRD) procedure might be used to indicate total body stores of vitamin A. OBJECTIVE: We studied the ability of 3-d DRD to detect changes in the body pool size of vitamin A and the effect of vitamin A status on the bioconversion of plant carotenoids to vitamin A. DESIGN: Two separate, unrelated studies were conducted in 7-13-y-old children with poor or marginal serum retinol concentrations (0.32-0.93 micromol/L) by feeding them controlled diets daily for 5 d/wk for 12 wk, after treatment with an anthelmintic drug. In school 1 (n = 27), lunch and 2 snacks that were provided at school contained 2258 retinol equivalents/d (mostly from orange fruit and vegetables) and 5.3 MJ/d from 33 g fat, 37 g protein, and 209 g carbohydrates; in school 2 (n = 25), 2 snacks provided 2.5 MJ/d from 9.4 g fat, 9.6 g protein, and 119 g carbohydrates, but no carotenes. RESULTS: In school 1, mean serum beta-carotene increased from 0.12 to 0.62 micromol/L (P = 0.0001) and serum retinol increased from 0.68 to 1. 06 micromol/L (P = 0.0001). In school 2, serum beta-carotene increased from 0.06 to 0.11 micromol/L (P = 0.0001) and serum retinol increased from 0.66 to 0.86 micromol/L (P = 0.0001). In school 1, but not school 2, improvement in serum retinol varied inversely with baseline retinol (r = -0.38, P = 0.048). In both schools, 3-d DRD showed reductions in the ratio of serum deuterated to nondeuterated retinol (D:H retinol) postintervention, denoting improvements in vitamin A status; the higher D:H retinol (ie, the poorer the status) at baseline, the greater the reduction in D:H retinol postintervention (school 1: r = -0.99, P = 0.0001; school 2: r = -0.89, P = 0.0001). CONCLUSIONS: Three-day DRD can detect changes in the body pool size of vitamin A, although a predictive equation to quantitate total body stores of vitamin A with the use of 3-d data needs to be developed. Bioconversion of plant carotenoids to vitamin A varies inversely with vitamin A status; improvement in status after dietary interventions is strongly influenced by total body stores of vitamin A and is influenced little or not at all by serum retinol.
BACKGROUND: It is important to understand the factors affecting strategies to improve the vitamin A status of populations. We reported previously that a 3-d deuterated-retinol-dilution (DRD) procedure might be used to indicate total body stores of vitamin A. OBJECTIVE: We studied the ability of 3-dDRD to detect changes in the body pool size of vitamin A and the effect of vitamin A status on the bioconversion of plant carotenoids to vitamin A. DESIGN: Two separate, unrelated studies were conducted in 7-13-y-old children with poor or marginal serum retinol concentrations (0.32-0.93 micromol/L) by feeding them controlled diets daily for 5 d/wk for 12 wk, after treatment with an anthelmintic drug. In school 1 (n = 27), lunch and 2 snacks that were provided at school contained 2258 retinol equivalents/d (mostly from orange fruit and vegetables) and 5.3 MJ/d from 33 g fat, 37 g protein, and 209 g carbohydrates; in school 2 (n = 25), 2 snacks provided 2.5 MJ/d from 9.4 g fat, 9.6 g protein, and 119 g carbohydrates, but no carotenes. RESULTS: In school 1, mean serum beta-carotene increased from 0.12 to 0.62 micromol/L (P = 0.0001) and serum retinol increased from 0.68 to 1. 06 micromol/L (P = 0.0001). In school 2, serum beta-carotene increased from 0.06 to 0.11 micromol/L (P = 0.0001) and serum retinol increased from 0.66 to 0.86 micromol/L (P = 0.0001). In school 1, but not school 2, improvement in serum retinol varied inversely with baseline retinol (r = -0.38, P = 0.048). In both schools, 3-dDRD showed reductions in the ratio of serum deuterated to nondeuterated retinol (D:H retinol) postintervention, denoting improvements in vitamin A status; the higher D:H retinol (ie, the poorer the status) at baseline, the greater the reduction in D:H retinol postintervention (school 1: r = -0.99, P = 0.0001; school 2: r = -0.89, P = 0.0001). CONCLUSIONS: Three-day DRD can detect changes in the body pool size of vitamin A, although a predictive equation to quantitate total body stores of vitamin A with the use of 3-d data needs to be developed. Bioconversion of plant carotenoids to vitamin A varies inversely with vitamin A status; improvement in status after dietary interventions is strongly influenced by total body stores of vitamin A and is influenced little or not at all by serum retinol.
Authors: Jesse Sheftel; Ashley R Valentine; Angela K Hull; Tetra Fadjarwati; Bryan M Gannon; Christopher R Davis; Sherry A Tanumihardjo Journal: Am J Clin Nutr Date: 2021-05-08 Impact factor: 7.045
Authors: Tilman Grune; Georg Lietz; Andreu Palou; A Catharine Ross; Wilhelm Stahl; Guangweng Tang; David Thurnham; Shi-an Yin; Hans K Biesalski Journal: J Nutr Date: 2010-10-27 Impact factor: 4.798
Authors: Rashidul Haque; Tanvir Ahmed; M A Wahed; Dinesh Mondal; A S M Hamidur Rahman; M John Albert Journal: J Health Popul Nutr Date: 2010-06 Impact factor: 2.000
Authors: Sherry A Tanumihardjo; Robert M Russell; Charles B Stephensen; Bryan M Gannon; Neal E Craft; Marjorie J Haskell; Georg Lietz; Kerry Schulze; Daniel J Raiten Journal: J Nutr Date: 2016-08-10 Impact factor: 4.798