Researchers in Germany recently published one of those studies that, now and then, make me question my core beliefs. I’m a supplement skeptic, but I try not to let that identity prevent me from assimilating new data. And if there’s one supplement whose possible benefits I’ve been on the fence about in recent years, it’s vitamin D.
The new study, which appears in the European Journal of Applied Physiology, is part of a major initiative to improve the performance of German elite athletes. A research team led by Sebastian Hacker of Justus Liebig University in Giessen studied 474 athletes on German national teams in a range of sports including hockey, table tennis, and three-on-three basketball. They tested vitamin D levels and measured (among other outcomes) handgrip strength.
Here’s the money shot:
This graph shows handgrip strength as a function of 25(OH)D levels, which is how vitamin D status is assessed in the blood. The two dashed lines indicate the thresholds between vitamin D deficiency (below 20 ng/mL), insufficiency (between 20 and 30…
