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Vitamin D

Peer-reviewed research concerning vitamin d, summarized and appraised in plain language with every source cited.

6Studies

6Human studies

2026Most recent

4Countries

Differential and Dose-Dependent Redistribution of Vitamin D Metabolites After Acute High-Intensity Exercise in Mixed Martial Arts Athletes and Untrained Men: Pilot Study.

Nutrients2026n = 34

RCTHuman

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…

Muscle & Strength Supplements Training optimization

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Vitamin D Adequacy Conditions the Prolactin-Suppressive Effect of Metformin in Men Receiving Prolactin-Elevating Medications.

Nutrients2026n = 75 enrolled, 70 completed

RCTHuman

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…

Endocrine Higher Testosterone Low Testosterone

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