Iron Absorption from Iron-Biofortified Sweetpotato Is Higher Than Regular Sweetpotato in Malawian Women while Iron Absorption from Regular and Iron-Biofortified Potatoes Is High in Peruvian Women

Abstract

Background: Sweetpotato and potato are fast-maturing staple crops and widely consumed in low-and middle-income countries. Conventional breeding to biofortify these crops with iron could improve iron intakes. To our knowledge, iron absorption from sweetpotato and potato has not been assessed. Objective: The aim was to assess iron absorption from regular and iron-biofortified orange-fleshed sweetpotato in Malawi and yellow-fleshed potato and iron-biofortified purple-fleshed potato in Peru. Methods: We conducted 2 randomized, multiple-meal studies in generally healthy, iron-depleted women of reproductive age. Malawian women (n = 24) received 400 g regular or biofortified sweetpotato test meals and Peruvian women (n = 35) received 500 g regular or biofortified potato test meals. Women consumed the meals at breakfast for 2 wk and were then crossed over to the other variety. We labeled the test meals with 57 Fe or 58 Fe and measured cumulative erythrocyte incorporation of the labels 14 d after completion of each test-meal sequence to calculate iron absorption. Iron absorption was compared by paired-sample t tests. Results: The regular and biofortified orange-fleshed sweetpotato test meals contained 0.55 and 0.97 mg Fe/100 g. Geometric mean (95% CI) fractional iron absorption (FIA) was 5.82% (3.79%, 8.95%) and 6.02% (4.51%, 8.05%), respectively (P = 0.81), resulting in 1.9-fold higher total iron absorption (TIA) from biofortified sweetpotato (P < 0.001). The regular and biofortified potato test meals contained 0.33 and 0.69 mg Fe/100 g. FIA was 28.4% (23.5%, 34.2%) from the regular yellow-fleshed and 13.3% (10.6%, 16.6%) from the biofortified purple-fleshed potato meals, respectively (P < 0.001), resulting in no significant difference in TIA (P = 0.88). Conclusions: FIA from regular yellow-fleshed potato was remarkably high, at 28%. Iron absorbed from both potato test meals covered 33% of the daily absorbed iron requirement for women of reproductive age, while the biofortified orange-fleshed sweetpotato test meal covered 18% of this requirement. High polyphenol concentrations were likely the major inhibitors of iron absorption. These trials were registered at www.clinicaltrials.gov as NCT03840031 (Malawi) and NCT04216030 (Peru).

Heterosis and Responses to Selection in Orange-Fleshed Sweetpotato (Ipomoea batatas L.) Improved Using Reciprocal Recurrent Selection

“…The observed response to selection in iron was moderate (19.4%), but, remarkably, almost all H 1 -O-HIFE offsprings exceeded the mean of the checks (99.8% with an H 1 -O-HIFE offspring mean of 8.2-mg kg –1 iron above the mean of checks). This is a significant improvement for this micronutrient, which is seriously deficient in food supply ( Jongstra et al, 2020 ). Outstanding clones such as PH17.9239 (45.9 mg kg –1 dwb iron and 31.6 mg kg –1 dwb zinc, results not presented) are an indication that double or triple biofortification might be possible with further RRS cycles.…”

Breeding Progress for Vitamin A, Iron and Zinc Biofortification, Drought Tolerance, and Sweetpotato Virus Disease Resistance in Sweetpotato

“…MUSG15052-2 (OFSP) bred in Mozambique had high Fe levels of 4.4 mg/100 g, DW (ICP method of analysis) was subjected to Fe bioavailability studies in Malawi in 2019 led by ETH-Zurich and the College of Medicine in Malawi. The work on bioavailability of Fe has been published elsewhere (Laryea et al, 2018;Jongstra et al, 2020).…”

The Potato of the Future: Opportunities and Challenges in Sustainable Agri-food Systems

“…Likewise, in developing countries, it contributes to combat micronutrient deficiency, also referred to as hidden hunger, that is a major global public health problem affecting an estimated 2 billion people globally (Bailey et al 2015). Improving the phyto-availability of iron and zinc from potato varieties in order to fortify the tubers for human consumption to reduce global micronutrient malnutrition can be achieved by breeding and agronomic fortification (Kromann et al 2016;Amoros et al 2020;Jongstra et al 2020). When eaten with its skin, a single medium-sized potato of 150 g provides nearly half the daily adult requirement (100 mg) of vitamin C. It is also a good source of vitamins B1, B3, and B6 and minerals such as iron, potassium, phosphorus, and magnesium and contains folate, pantothenic acid, and riboflavin.…”