Guava fruit with a habitual rice-based meal enhances iron bioavailability in adolescents

Guava fruit with a habitual rice-based meal enhances iron bioavailability in adolescents: study

Posted on April 18, 2013 by Stone Hearth News

Inclusion of Guava Enhances Non-Heme Iron Bioavailability but Not Fractional Zinc Absorption from a Rice-Based Meal in Adolescents 1,2

Krishnapillai Madhavan Nair 3,*,
Ginnela N.V. Brahmam 4,
Madhari S. Radhika 4,
Roy Choudhury Dripta 3,
Punjal Ravinder 3,
Nagalla Balakrishna 5,
Zhensheng Chen 6,
Keli M. Hawthorne 6, and
Steven A. Abrams 6
First published April 17, 2013, doi: 10.3945/​jn.112.171702 J. Nutr. June 1, 2013 jn.112.171702
+ Author Affiliations
3 Divisions of Micronutrient Research National Institute of Nutrition, Indian Council of Medical Research, Hyderabad, India
4 Divisions of Community Studies and the National Institute of Nutrition, Indian Council of Medical Research, Hyderabad, India
5 Department of Biostatistics, National Institute of Nutrition, Indian Council of Medical Research, Hyderabad, India; and
6 USDA/Agriculture Research Service, Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine and Texas Children’s Hospital, Houston, TX
↵*To whom correspondence should be addressed. E-mail: nairthayil@gmail.com.
Abstract

Assessing the bioavailability of non-heme iron and zinc is essential for recommending diets that meet the increased growth-related demand for these nutrients. We studied the bioavailability of iron and zinc from a rice-based meal in 16 adolescent boys and girls, 13–15 y of age, from 2 government-run residential schools. Participants were given a standardized rice meal (regular) and the same meal with 100 g of guava fruit (modified) with 57Fe on 2 consecutive days. A single oral dose of 58Fe in orange juice was given at a separate time as a reference dose. Zinc absorption was assessed by using 70Zn, administered intravenously, and 67Zn given orally with meals. The mean hemoglobin concentration was similar in girls (129 ± 7.8 g/L) and boys (126 ± 7.1 g/L). There were no sex differences in the indicators of iron and zinc status except for a higher hepcidin concentration in boys (P < 0.05). The regular and modified meals were similar in total iron (10–13 mg/meal) and zinc (2.7 mg/meal) content. The molar ratio of iron to phytic acid was >1:1, but the modified diet had 20 times greater ascorbic acid content. The absorption of 57Fe from the modified meal, compared with regular meal, was significantly (P < 0.05) greater in both girls (23.9 ± 11.2 vs. 9.7 ± 6.5%) and boys (19.2 ± 8.4 vs. 8.6 ± 4.1%). Fractional zinc absorption was similar between the regular and modified meals in both sexes. Hepcidin was found to be a significant predictor of iron absorption (standardized β = −0.63, P = 0.001, R2 = 0.40) from the reference dose. There was no significant effect of sex on iron and zinc bioavailability from meals. We conclude that simultaneous ingestion of guava fruit with a habitual rice-based meal enhances iron bioavailability in adolescents.
Footnotes
↵1 Supported by grants from Indian Council of Medical Research (project no.63/4/Indo-US/2003-RHN) and the National Institutes of Health (HD061032).
↵2 Author disclosures: K. M. Nair, G. N. V. Brahmam, M. S. Radhika, R. C. Dripta, P. Ravinder, N. Balakrishna, Z. Chen, K. M. Hawthorne, and S. A. Abrams, no conflicts of interest.
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