High dose vitamin D supplementation safe for diabetics


The conduct of the trial was supported primarily by the NIDDK and the Office of Dietary Supplements of the National Institutes of Health

High dose vitamin D supplementation safe for diabetics

Recent research published in Nature has investigated supplementation with high doses of vitamin D3 in prediabetic individuals. After testing the incidence of adverse events (AEs) in the study’s participants across a three-year period, researchers concluded supplementation at 4000 IU per day was both safe and well tolerated among participants at high risk for diabetes.

According to the researchers, the study responds to a substantial increase in routine usage of vitamin D supplements in the US. While the vitamin may exhibit potential preventative benefits for various chronic diseases including diabetes, the researchers argue there is currently not enough evidence confirming the safety of supplementation at the higher concentrations now being considered.

For this randomised, double-blind, placebo-controlled trial, 2423 overweight or obese people with prediabetes took either 4000 UI of vitamin D3 (the upper tolerable limit according to the National Academy of Medicine) or a placebo once daily. The researchers followed up with participants four times annually throughout the following three years to track AEs, which were defined as “untoward or unfavourable medical occurrences”. The researchers also tracked Serious AEs, such as death, life-threatening events and hospitalisation.

More than 8300 AEs were registered throughout the follow-up period, however these incidences were lower in the supplementation group than in the placebo group. Specified AEs of interest, which have previously been associated with vitamin D supplementation (nephrolithiasis, hypercalcemia, hypercalciuria and low estimated glomerular filtration rate) saw a low overall occurrence with no group-specific weighting.

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In light of these findings, the researchers concluded vitamin D supplementation at high doses should be considered safe and well tolerated in prediabetics.