Active — Not RecruitingNot Applicable

Acute Vitamin D Supplementation on Testosterone in Females

United States20 participantsStarted 2025-07-01

Plain-language summary

Participation will take place over two visits to the Clinical Exercise Research Center (CERC) at the University of Southern California Health Sciences Campus. On the first visit, height, weight, and body composition by bioelectrical impedance are recorded. Questionnaires and withdrawal of a sample of blood (1 tablespoon) are also completed. The intervention begins the day following the first visit. The intervention protocol consists of three weeks of consuming either a placebo capsule or a 5000 IU Vitamin D capsule daily and completing a daily survey. The second visit to CERC immediately follows the 3-weeks intervention. In this visit, the same blood sampling protocol will be completed. The assignment of the intervention will be randomized (i.e., rolling a die), and participants are blinded to group assignment.

Who can participate

Age range18 Years – 35 Years

SexFEMALE

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AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Assigned female at birth * 18 to 35 years of age * No chronic diseases affecting the uptake of Vitamin D or causing Vitamin D sensitivity (e.g., sarcoidosis, tuberculosis, Wegener's granulomatosis, other forms of vasculitis, inflammatory bowel diseases, etc.) \[21\] * Completion and signature of the informed consent document * Non-pregnant or trying to become pregnant * No supplementation with Vitamin D within three months of enrollment * No documented gynecological disease (e.g., PCOS, endometriosis, etc.) * Weight greater than or equal to 110 lbs Exclusion Criteria: * Pregnant * Supplementation with Vitamin D within three months of enrollment * Taking exogenous hormones * Documented gynecological disease (e.g., PCOS, endometriosis, etc.) * Suffering from chronic diseases affecting the uptake of Vitamin D or causing Vitamin D sensitivity (e.g., sarcoidosis, tuberculosis, Wegener's granulomatosis, other forms of vasculitis, inflammatory bowel diseases, etc.) \[21\] * Weight less than 110 lbs

What they're measuring

Hormonal Effects of Vitamin D in Young, Healthy Women

Timeframe: 3 weeks

Hormonal Effects of Vitamin D in Young, Healthy Women

Timeframe: 3 weeks

Hormonal Effects of Vitamin D in Young, Healthy Women

Timeframe: 3 weeks

Hormonal Effects of Vitamin D in Young, Healthy Women

Timeframe: 3 weeks

Trial details

NCT IDNCT06610968

SponsorUniversity of Southern California

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2026-03-05

View on ClinicalTrials.gov More Female Hormone Profile trials

Plain-language summary

Who can participate

Age range18 Years – 35 Years

SexFEMALE

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.