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Vitamin D

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

11Studies

11Human studies

2026Most recent

4Countries

Cross-Sectional Association of Time Spent Outdoors With Serum Testosterone: Results From the National Health and Nutrition Examination Survey.

The Journal of urology2026n = 2,205 men

Cross SectionalHuman

This study looked at whether time spent outdoors is linked to testosterone in men. It analyzed 2,205 men in the US National Health and Nutrition Examination Survey, tracking daily outdoor…

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Bright Light Exposure Is Positively Associated with Serum Testosterone in Adult Men: A National Cross-sectional Analysis.

European urology focus2026n = 2209

Cross SectionalHuman

This study set out to see whether exposure to bright light is linked to testosterone in men, an area far less studied than diet and exercise. It analyzed data from…

Endocrine Higher Testosterone Low Testosterone

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Association between vitamin D status and triglyceride-glucose index among South Korean adults: a cross-sectional study.

Clinical nutrition research2026n = 4,819

Cross SectionalHuman

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,…

Aging Heart Health Longevity

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