Selenium and Type 2 Diabetes: Systematic Review

Abstract

Several studies have investigated the potential role of selenium (Se) in the development of type 2 diabetes (T2D) with disparate findings. We conducted a systematic review and meta-analysis to synthesize the evidence of any association between Se and T2D. PubMed, Embase, and Scopus were searched following the Preferred Reporting Items for Systematic Reviews and Meta-analysis Approach (PRISMA). Sixteen studies from 15 papers met inclusion criteria defined for this review. Of the 13 observational studies included, 8 demonstrated a statistically significant positive association between concentrations of Se and odds for T2D, with odds ratios (95% confidence intervals) ranging from 1.52 (1.01–2.28) to 7.64 (3.34–17.46), and a summary odds ratio (OR) (95% confidence interval (CI)) of 2.03 (1.51–2.72). In contrast, among randomized clinical trials (RCTs) of Se, a higher risk of T2D was not observed for those who received Se compared to a placebo (OR = 1.18, 95% CI 0.95–1.47). Taken together, the results for the relationship between Se and T2D differ between observational studies and randomized clinical trials (RCTs). It remains unclear whether these differences are the result of uncontrolled confounding in the observational studies, or whether there is a modest effect of Se on the risk for T2D that may vary by duration of exposure. Further investigations on the effects of Se on glucose metabolism are needed.

Effectiveness and safety of selenium supplementation for type 2 diabetes mellitus in adults: a systematic review of randomised controlled trials

“…As a chronic hyperglycaemia can cause a substantial increase of reactive oxygen species (ROS) and oxidative stress, leading to diabetes‐related complications and a decreased Se level , it was hypothesised that, in patients diagnosed with T2DM, Se supplementation may be beneficial. However, a number of studies indicate that it may act adversely on glucose homeostasis and insulin sensitivity and even increase the risk of T2DM . This can be partially explained by the impact of Se on selenoproteins and insulin signalling .…”

“…Therefore, the potential benefits of Se need to be balanced with possible harms. Recently, in 2018, two systematic reviews of randomised controlled trials ( RCT s) showed equivocally the effect of selenium on T2DM development .…”

Effect of selenium supplementation on glycemic indices: a meta-analysis of randomized controlled trials

“…However, RCTs of selenium did not indicate a higher risk of T2D in individuals receiving selenium as compared with placebo group. In this study, the associations between selenium and risk of T2D were observed in the observational studies which were not repeated in the RCT studies [39].…”

Ernährung bei Diabetes mellitus Typ 2

“…Dabei hatten hohe Selen-und Kupferwerte einen höheren HbA 1c -Spiegel zur Folge. Ursächlich dafür könnte unter anderem eine Störung der Insulinsignalkaskade durch insulinähnliche Wirkungen von Selenoproteinen sein [9] [11].…”

“…Bezüglich der Entstehung eines Typ-2-Diabetes nach Supplementierung gibt es bislang keinen Nachweis [11].…”