Ingestion of supplements and fortified food with iodine on the breast milk iodine concentration in deficiency areas: a systematic review

Introduction: The level of iodine in breast milk may be inadequate and compromise the health of this, both due to excess and lack, some population groups remain deficient because of the low consumption of iodate salt, because there is an in- crease in consumption of other sources of iodine, such as supplements and fortified foods. Objective: To evaluate the effect of the consumption of fortified foods and nutritional supplements with iodine on mater- nal milk levels. Methodology: Systematic review based on the Prism method, using the descriptors provided by DeCS. The reading, selec- tion and analysis of the methodological quality of the articles was done by two researchers independently. Results: From 346 abstracts, 6 were eligible. The median iodination range between the studies ranged from 75 to 600 μg in supplements and 150 and 225 μg in fortified foods with effect on increased iodine concentration of breastmilk (BMIC), achieving the adequacy of the median BMIC in 4 of the 6 studies. Conclusion: Iodine ingestion through supplements or fortified foods results in improved iodine levels in breast milk. Keywords: Iodine; supplements; fortified foods; breastmilk; iodine concentration.

Comparison of breast-milk iodine concentration of lactating women in Australia pre and post mandatory iodine fortification

ObjectiveTo compare the breast-milk iodine concentrations (BMIC) of lactating women before and after the mandatory iodine fortification of bread in Australia in 2009.DesignCross-sectional study. Breast milk samples were collected from two cohorts of women in South Australia within 7 d of delivery to determine BMIC. The percentage of samples with iodine concentration below 100 µg/l, a level considered adequate for breast-fed infants, was calculated. Sociodemographic information and intake of dietary supplements were obtained from all women.SettingThe breast milk samples were collected between 2006 and 2007 in the pre-fortification cohort and between 2012 and 2013 in the post-fortification cohort.ResultsThe median (interquartile range) BMIC was higher in the post-fortification samples compared with samples collected in the pre-fortification period (187 (130–276)v.103 (73–156) µg/l;P<0·05). Overall, the percentage of women with BMIC <100 µg/l was lower in the post-fortification cohort than in the pre-fortification cohort (13v.49 %;P<0·01). The percentage of women with BMIC <100 µg/l in the post-fortification cohort was lower among women who took iodine supplements in pregnancy (12v. 29 %;P<0·01).ConclusionsMandatory iodine fortification of bread has resulted in an increase in the iodine content of breast milk in Australian women. However, iodine supplementation may still be required in some women post-iodine fortification to reach the level of BMIC that is considered adequate to meet the iodine requirement of full-term infants.

Urinary Iodine Excretion of Lactating Mothers Predicts the Iodine Content of Their Breast Milk

Background: Iodine is essential for normal growth, mental development and survival of infants. Bangladesh is an iodine deficient region. Breast milk is the only source of iodine for exclusively breast-fed infants. Routine measurement of breast milk iodine concentration is very difficult in our country due to some social and religious barriers. So, we designed this study in our population using urinary iodine as the indicator for assessing iodine status. Objectives: To assess the iodine status of lactating mothers and their breast-fed infants and to propose a method on how to predict the iodine concentration in breast milk. Materials and Methods: This observational analytical study was carried out in the department of Biochemistry, Bangabandhu Sheikh Mujib Medical University, Dhaka with active cooperation of Kumudini Women’s Medical College Hospital, Mirzapur, Tangail involving fifty lactating mothers and their exclusively breast-fed infants. Early morning urine and breast milk samples were collected in dry and clean plastic container free from any chemical contamination. All statistical analyses were done by using SPSS (Statistical Programme for Social Science) 12 version software package for windows. Results: The median (range) urinary iodine concentration of lactating mothers and their breast-fed infants were 225.25 ?g/L (61.50-530.00) and 225.75 ?g/L (100.50-526.50). 96% (48) mothers had no biochemical iodine deficiency (UIE ?100?g/L), only 4% (2) mothers had mild biochemical iodine deficiency (UIE 50-99?g/L). There was no biochemical deficiency of breast-fed infants. The median (range) breast-milk iodine concentration was 157 ?g/L (54.50-431.50) which was more than three times of recommended minimum concentration (50 ?g/L). Iodine in breast milk of lactating mothers positively correlated with their urinary iodine excretion (P<0.01). Infant’s urinary iodine positively correlated with iodine concentration in breast milk (P<0.01) and also positively correlated with urinary iodine excretion of lactating mothers. Conclusion: Lactating mothers and their breast-fed infants in this study were found iodine sufficient. Urinary iodine concentration of lactating mothers predicts the iodine content of their breast milk. DOI: http://dx.doi.org/10.3329/jemc.v1i1.11132J Enam Med Col 2011; 1(1): 15-18