Iodine status of lactating mothers and infants aged 0 to 6 months in Vhembe and Mopani district of the Limpopo Province, South Africa

Abstract

Introduction: Iodine is an essential nutrient required by humans for the synthesis of thyroid hormones, which are vital for normal growth and development. Objective: The primary aim of the study was to describe the iodine status of lactating mothers and infants aged from 0 to 6 months in the Vhembe and Mopani Districts. Methods: A cross-sectional study conducted on 246 infant-mother pair, from the Mopani and the Vhembe Districts. Data was gathered using a questionnaire. Breastmilk, mother urine, infant urine, household salt and drinking water were collected to be analysed for iodine content. Results: The median of breastmilk iodine concentration level amongst lactating mothers in the Vhembe District was 101.4 µg/l (IQR 62.9 – 175.1 µg/l) and 154.4 µg/l (IQR 92.6 – 211.8 µg/L) in Mopani. The median UIC of mothers in Vhembe was 98.5 (IQR 57.66 – 153.93), whereas in the Mopani District the median UIC of mothers was 126.08 µg/l (IQR 69.89 – 206.71 µg/L). The median UIC of infants in Vhembe was 220 (IQR 106.67 – 418.43 µg/l) and in the Mopani District was 321.94 µg/l (IQR 167.96 – 482.66 µg/l). Conclusion: The BMIC in the study signifies iodine sufficiency in both the Vhembe and the Mopani Districts. The results of this study suggest that the BMIC be included in studies assessing iodine status in lactating mothers since the UIC only reflects iodine that was consumed recently. The UIC may under estimate the maternal iodine status if it is not complemented by the BMIC data.