Peer-reviewed research concerning vitamin d, summarized and appraised in plain language with every source cited.
This systematic review and meta-analysis set out to see whether vitamin D supplements raise testosterone or related markers in men. It pooled randomized trials measuring total testosterone, SHBG (sex hormone-binding…
This study looked at how high-intensity exercise and vitamin D3 supplements affect vitamin D levels differently in trained athletes versus untrained men. It compared 22 mixed martial arts athletes and…
This study looked at whether vitamin D levels are linked to metabolic health, measured by the TyG index (a score from fasting blood sugar and triglycerides that flags insulin resistance,…
This study looked at whether vitamin D changes how well metformin (a common diabetes drug that lowers blood sugar) can bring down prolactin (a pituitary hormone that suppresses testosterone when…