The Influence of Iron and Zinc Supplementation on the Bioavailability of Provitamin A Carotenoids from Papaya Following Consumption of a Vitamin A-Deficient Diet

Abstract

Summary Iron deficiency anemia, zinc and vitamin A deficiencies are serious public health problems in Cameroon, as in many developing countries. Local vegetables which are sources of provitamin A carotenoids (PACs) can be used to improve vitamin A intakes. However, traditional meals are often unable to cover zinc and iron needs. The aim of this study was to determine the bioavailability of 3 PACs (a-carotene, b-carotene, and b-cryptoxanthin) in young men, who were fed with a vitamin A-free diet and received iron and zinc supplementation. Twelve healthy participants were divided into three groups and were supplemented with elemental iron (20 mg of iron fumarate), 20 mg of zinc sulfate or iron1zinc (20 mg of iron in the morning and 20 mg of zinc in the evening) for 11 d. They were given a vitamin A-and PAC-free diet from the 6th to the 11th day, followed by a test meal containing 0.55 kg of freshly peeled papaya as a source of PACs. Blood samples were collected four times successively on the 11th day (the test meal day), at T0 (just after the test meal), after 2 h (T2), after 4 h (T4) and after 7 h (T7). Ultracentrifugation was used to isolate serum chylomicrons. Retinol appearance and PAC postprandial concentrations were determined. The supplementation with zinc, iron and iron1zinc influenced the chylomicron appearance of retinol and PACs differently as reflected by retention times and maximum absorption peaks. Iron led to highest retinol levels in the chylomicron. Zinc and iron1zinc supplements were best for optimal intact appearance of a-carotene, b-carotene and b-cryptoxanthin respectively. Supplementation with iron led to the greatest bioavailability of PACs from papaya and its conversion to retinol.

Host‐related factors explaining interindividual variability of carotenoid bioavailability and tissue concentrations in humans

“…Also a low zinc status appears to reduce β‐carotene absorption from the gut , perhaps as phospholipase A2 can bind zinc and may be more active. These effects were confirmed in human studies, where supplementation with iron and zinc following a vitamin A deficient diet improved retinol and carotenoid plasma appearance, respectively . Also low protein status appears to hinder conversion of β‐carotene to vitamin A, contributing to carotenoid variability .…”

The effects of zinc supplementation on zinc, retinol and carotene levels in lactating Amazonian women

“…Tackling zinc deficiency in isolation is considered inappropriate however (Shrimpton et al 2005) and including zinc in multiple micronutrient supplementation and fortification interventions and promoting their use through existing programmes aimed at tackling anaemia for example will be less disruptive, avoiding further fragmentation of health service interventions. Indeed, zinc together with iron supplements have been shown recently to have a greater effect on carotene absorption than zinc supplements alone (Kana-Sop et al 2015).…”

Nutraceutical potentials of synergic foods: a systematic review

“…Vitamin A and iron Increases the bioavailability of pro-vitamin A carotenoids, including alpha-carotene, beta-carotene, and beta-cryptoxanthin [52]; increases iron absorption, especially non-heme iron [53]; reverse iron deficiency anemia [54] A review of dietary supplementation suggests that although supplements may be beneficial in states of insufficiency, the safe middle ground for consumption likely is food. Also, food provides a buffer during absorption.…”