Synbiotic supplementation is not effective on breast milk selenium concentrations and growth of exclusively breast fed infants: a pilot study

Abstract

Abstract. In this randomized, double-blind, placebo-controlled trial, 57 lactating mothers were randomly allocated into two groups to receive a daily supplement of synbiotic (n = 30) which contained different probiotic strains (2.0 × 108 CFU) and fructooligosaccharide (394 mg) or a placebo (n = 27) for 30 days. Dietary intake was collected from lactating women by 24-hour recall method. Breast milk selenium contents were determined by atomic absorption spectrometry with graphite furnace. Weight for age Z-score (WAZ) and Height for age Z-score (HAZ) were evaluated for infants. Data analyses were assessed using nutritionist IV, Epi Info and SPSS software and presented as mean ± sd or SEM. The total mean breast milk selenium levels were 50.1 ± 16.1 mcg L−1. At the baseline, the mean breast milk selenium concentrations in the synbiotic and placebo groups were 51.7 ± 20.2 and 48.5 ± 12.1 mcg L−1. The mean breast milk selenium levels increased and decreased in the symbiotic and placebo groups respectively, which were not significant (p > 0.05). Also, comparison of the changes in breast milk selenium concentration showed no significant difference between the two study groups after the intervention. At the baseline, the mean WAZ and HAZ of infants whose mothers’ milk selenium was more than 60 mcg/l was significantly (P < 0.05) higher than for others. In this pilot study, no significant effect was observed by synbiotic supplementation, however, for concise conclusion, more human studies with higher doses of supplements and longer duration of supplementation are needed to determine the effects of synbiotic supplementation on breast milk selenium contents and infants’ growth.