Researchers publishing in Nature Communications found that daily consumption of iron- and zinc-biofortified pearl millet caused no detectable adverse effects on the developing gut microbiomes of young children. The randomized controlled trial tracked children aged 12 to 18 months from Mumbai urban slums who did not suffer from severe anemia, defined as having hemoglobin levels of at least 9.0 g/dL.
Participants received either biofortified pearl millet containing 8.70 mg of iron per 100 grams or control pearl millet containing 3 mg of iron per 100 grams over a nine-month period. Researchers used shotgun metagenomics to profile the children's gut microbiomes, evaluating paired samples from 81 participants and endpoint samples from 108 participants. The trial, registered as NCT02233764 on ClinicalTrials.gov, originally targeted iron status biomarkers and infant growth as its primary outcomes.
Exploratory findings indicated that biofortified pearl millet may promote beneficial metabolic adaptations by directly modulating antibiotic, antioxidant, and pollutant degradation pathways. Conventional iron supplementation in children under five can prompt unwanted shifts in gut bacteria. The trial authors noted that biofortified crops could offer a sustainable food-based approach to address iron deficiency while preserving healthy microbiome development in early life.
Samantha L. Huey and Nathaniel L. Cole served as co-first authors of the study, collaborating with researchers across Cornell University, the University of California San Diego, St. John’s Research Institute in Bangalore, SNDT Women’s University, and the Centre for the Study of Social Change in Mumbai. SRL Diagnostics in Mumbai and Genotypic Pvt. Ltd. in Bangalore facilitated the organization, storage, and analysis of biological samples.
Funding for the publication came in part from a Gates Foundation grant awarded to HarvestPlus, alongside grants from the United States Department of Agriculture National Institute of Food and Agriculture and the National Institutes of Health. HarvestPlus receives principal funding from UK International Aid, the Government of Canada, the Gates Foundation, the Happel Foundation, and the Church of Jesus Christ of the Latter-Day Saints.
