Selenium Supplementation and Blood Sugar Levels

Testing blood sugar
The results of randomized controlled trials of selenium supplementation show beneficial effects or no effect on blood sugar levels and insulin sensitivity values. In this review, we summarize the study results.

The effect of selenium supplementation on blood sugar levels and on the risk of diabetes is still an open question. However, the data from randomized controlled studies show that selenium supplementation is associated with either a beneficial effect or no effect at all on blood sugar levels, insulin sensitivity, and glucose tolerance [Jablonska 2016].

Study Participants with Type-2 Diabetes

Beneficial effect. In a 2019 study, the participants were 72 male and 22 female patients aged 48 to 64 years old with diabetes mellitus type 2. They were smokers, all of them, and they all followed a Mediterranean diet.

The researchers administered selenium 200 microg/day once daily on an empty stomach. The study data showed a statistically significant reduction in the blood levels of glucose and in HbA1c values at both three months and six months after the beginning of the treatment. The administration of selenium to type-2 diabetic patients seemed to improve the patients’ glycemic profile [Karalis 2019]. read more

Selenium Supplementation and Prostate Cancer

New Zeland landscape
The New Zealand study results suggest that each of us needs to take personalized selenium supplement dosages based on our individual characteristics rather than have all of us take the same 200 microg/day tablet for prostate health benefits [Karunasinghe 2019].
Demographic, dietary, genetic, and life style factors influence the prostate health effects of selenium supplementation according to New Zealand researchers.

An inverse association between serum selenium concentrations and prostate-specific antigen levels was especially strong in the following sub-groups of study participants [Karunasinghe 2019]:

  • men below the age of 55 years
  • men who never smoked
  • men carrying the GPX1 rs1050450 T allele
  • men with dietary intakes above the recommended daily intake for zinc (11 mg)
  • men with dietary intakes below the recommended daily intake for vitamin B12 (15 mcg)

Moreover, the increase in serum selenium status and the resulting post-supplementation serum selenium status were significantly dependent upon baseline serum status [Karunasinghe 2019].

The overall gain in serum selenium levels from supplementation declined at a rate of 0.828 microg/L with each one microg/L increase in baseline serum selenium level [Karunasinghe 2019]. read more