Definition: "An ergogenic aid is any substance or phenomenon that enhances performance "
The antidiabetic effect of vitamin D
Yesterday we wrote about a trial in which vitamin D supplementation improved glucose metabolism in pre-diabetics. The effect was positive, but not sky-shattering. The subjects' vitamin D levels were also pitifully low. Does vitamin D supplementation also work with a less unfavorable vitamin D level?
And the answer is...
In the 2013 trial, the Iranians experimented with 100 adult type 2 diabetes patients. The patients were given oral medications for their condition, such as glibenclamide or metformin. They weren't on insulin yet.
During the 8 weeks that the study lasted, the subjects took a capsule containing 50,000 units of vitamin D3 every week.
There was no control group.
The HOMA-IR, a marker for insulin resistance, dropped. This was also the case with the fasting glucose and insulin levels. All of these effects were statistically significant.
Using the study participants' baseline vitamin D levels, the researchers split the effect of their supplementation regimen on the HOMA-IR. Based on this data, we cobbled together the graph below.
The figure suggests that supplementation with vitamin D can bring about a small but possibly clinically relevant improvement in glucose metabolism at both relatively low and relatively high vitamin D levels.