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Sun & Vitamin D

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

3Studies

3Human studies

2026Most recent

3Countries

Vitamin D Supplementation, Total Testosterone, and Androgen Bioavailability Markers in Adult Men: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Nutrients2026n = 21 comparison-level records from 18 reports

Meta AnalysisHuman

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…

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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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Sex-specific associations of serum 25-hydroxyvitamin D concentrations with incident sarcopenia in older adults: A 2-year follow-up study.

The journal of nutrition, health & aging2025n = 1,292 (53% women)

CohortHuman

This study looked at whether vitamin D levels in the blood are linked to developing sarcopenia (age-related muscle loss) in older adults. It followed 1,292 Korean adults aged 70-84 without…

Aging Muscle & Strength Musculoskeletal

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