Mineral Composition of Indigenous Leafy Vegetables and Their Potential Contribution to Micronutrient Adequacy among Rural Households in Bo and Pujehun Districts, Sierra Leone

Abstract

Indigenous leafy vegetables may provide locally available sources of essential minerals and contribute to dietary diversity in rural communities, yet evidence on their mineral composition and relevance to mineral adequacy remains limited. This study assessed the mineral composition of selected indigenous leafy vegetables and their relevance to mineral adequacy among rural households in the study area. A cross-sectional study was conducted among 800 rural households comprising 2,368 participants, including 1,568 adults and 800 children aged 6–23 months. Household dietary intake was assessed using 24-hour dietary recalls and a 7-day food frequency questionnaire. Five indigenous leafy vegetables were analysed for calcium, iron, potassium, magnesium, sodium, phosphorus, and zinc using standard laboratory methods. Nutrient adequacy ratios (NARs) were used to assess selected mineral intakes. Significant differences were observed among the vegetables (p < 0.001). “Sorrel” had the highest concentrations of calcium (22,035.69 ± 265.24 mg/kg) and iron (2,003.43 ± 3.11 mg/kg), “Kponhula” had the highest concentrations of magnesium (6,188.39 ± 32.86 mg/kg), sodium (709.19 ± 16.11 mg/kg), and zinc (43.42 ± 0.58 mg/kg), sweet-potato leaves had the highest phosphorus concentration (4,857.46 ± 4.43 mg/kg), and “Popodaa” had the highest potassium concentration (44,467.57 ± 248.17 mg/kg). Among adults, mean NARs were 0.23 ± 0.14 for calcium, 1.18 ± 0.59 for iron, and 0.52 ± 0.26 for zinc. Among children aged 6–23 months, mean daily intakes were 140.56 mg calcium, 3.78 mg iron, and 1.89 mg zinc, with available NAR estimates of approximately 0.38 for calcium and 0.75 for zinc. The findings demonstrate substantial variation in the mineral profiles of the selected indigenous leafy vegetables, indicating potential nutritional relevance, particularly for calcium and zinc, which showed lower dietary adequacy in the study population. Indigenous leafy vegetables may therefore be considered as components of dietary-diversity and food-based nutrition strategies in rural Sierra Leone.