A healthy pregnancy. Selenium is an essential trace element needed to support a healthy pregnancy. However, to date, studies of the mother’s selenium status and the child’s growth and development are scarce. Data from the Odense Child Cohort study in Denmark give researchers an opportunity to investigate the possible effects of the mother’s low selenium intake and low selenium status on the child’s neuro-development [Demircan 2023; Demircan 2024].
Selenium-Enriched Yeast Supplementation Studies
The rationale for taking a selenium-enriched yeast preparation: one or more of the selenium compounds in the preparation other than selenomethionine may be the selenium species that has specific effects against cancer. This is an area for further research.
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This week, we focus on studies conducted with a selenium-enriched yeast preparation containing at least 20 different species of selenium in addition to selenomethionine [Bendahl & Gammelgaard 2004].
Randomized, double-blind, controlled clinical trials are the gold standard method for testing the safety, absorption, and efficacy of nutritional supplements and medical drugs. Below, we summarize some of the important clinical trials of nutritional interventions using selenium-enriched yeast.
Selenium Status and the Risk of Gestational Diabetes
Lower selenium status during pregnancy means there is a greater risk of developing gestational diabetes [Hamdan 2022; Xu 2022]. Three different selenium biomarkers in early and late pregnancy show a quite strong association of selenium with 1) the risk of developing gestational diabetes mellitus and 2) the birth of large for gestational age offspring [Demircan 2022].
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The Mayo Clinic defines gestational diabetes as being diagnosed with diabetes for the first time during pregnancy. Gestational diabetes is like other forms of diabetes in that it affects how well the cells use glucose. It causes high blood sugar levels that can affect the mother’s health and the baby’s health [Mayo Clinic 2023].
Selenium Supplementation and Preeclampsia Risk
Selenium supplementation of pregnant women at a high risk of preeclampsia has shown beneficial effects on 1) serum selenium levels, 2) some metabolic profiles, 3) uterine artery pulsatility index, and 4) mental health, compared to placebo. The study compared the effect in 60 pregnant women of supplementation with 200 mcg/day for 12 weeks with the effect of placebo for the same period.
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The supplementation took place for 12 weeks starting in weeks 16 to 18 of pregnancy. No side effects related to the intake of 200 mcg of selenium per day by pregnant women at high risk of preeclampsia were reported throughout the duration of the study [Mesdaghinia 2022].
Selenium Supplementation Compared to Placebo
How did the selenium supplementation compare with the placebo supplementation in the pregnant women?