Iodine status, including breastmilk iodine content, of lactating mothers and their infants aged 0 to 6 months in Vhembe and Mopani districts of the Limpopo province, South Africa

Background. Both iodine deficiency and excess may affect lactating women and their infants. In Limpopo Province, South Africa (SA), there are no data on the iodine status of individuals in these vulnerable groups. Objective. To determine the iodine status, including breastmilk iodine content, of lactating mothers and their infants aged 0-6 months in Vhembe and Mopani districts, Limpopo, SA. Methods. A cross-sectional descriptive study in the quantitative domain was undertaken in Vhembe and Mopani districts. Mother-infant pairs were randomly selected. Breastmilk iodine content (BMIC), urinary iodine content (UIC) of infants, UIC of mothers, household (HH) salt iodine content (SIC) and water iodine content (WIC). The iodine nutrition knowledge of mothers was determined. Results. The median (interquartile range (IQR)) of BMIC among lactating mothers in Vhembe and Mopani was 102 (62-179.7) µg/L and 150.4 (89.4-201.7) µg/L, respectively. The median (IQR) UIC of mothers in Vhembe and Mopani was 96.3 (54.8-154.8) µg/L and 137.9 (72-212.4) µg/L, respectively. The median UIC of infants was 217.7 (107.1-409.9) and 339.8 (162.9-490.3) µg/L in Vhembe and Mopani, respectively. There was a significant difference between SIC of coarse and fine salt in both districts. Lactating mothers in both areas had limited iodine nutrition knowledge. Conclusion. The results suggest that iodised salt is a major contributor to iodine status in lactating mothers and their infants. Our results also show that the salt iodisation programme in SA supplies sufficient iodine for children, women of reproductive age, lactating mothers and breastfed infants.