The goal of this clinical trial is to understand the effects of oral vitamin D3 supplementation on various cardiovascular risk factors in generally healthy, young adult black women who are vitamin D deficient or insufficient at baseline. The main questions it aims to answer are: Does 8 weeks of vitamin D3 supplementation (5,000 IU per day) improve 24 hour blood pressure metrics in generally healthy, young adult black women who are vitamin D deficient or insufficient at baseline? Does 8 weeks of vitamin D3 supplementation (5,000 IU per day) improve objectively estimated sleep duration and regularity in generally healthy, young adult black women who are vitamin D deficient or insufficient at baseline? Does 8 weeks of vitamin D3 supplementation (5,000 IU per day) improve various measures of blood vessel structure and function in generally healthy, young adult black women who are vitamin D deficient or insufficient at baseline? All participants will undergo baseline testing, which includes 2 continuous weeks of objective sleep monitoring using a sleep watch, one 24-hour period of ambulatory blood pressure monitoring, and one blood vessel function testing visit. Following baseline testing, participants will be randomized to take either 5,000 IU of vitamin D3 or a placebo pill daily for 8 continuous weeks. Participants will undergo 2-weeks of sleep monitoring again during weeks 3-4 of the supplementation period and during weeks 7-8 of the supplementation period. Additionally, 24-hour blood pressure monitoring will be performed during week 4 and week 8, and blood vessel function testing will take place at the end of week 4 and again at the end of week 8. Researchers will compare the vitamin D3 and placebo groups to see if there is any effect of vitamin D3 supplementation on 24-hour blood pressure, sleep duration and regularity, and blood vessel structure and function following 4 and 8 weeks of supplementation.
2 Primary · 3 Secondary · Reporting Duration: Change in pulse wave velocity from baseline, week 4, and week 8
Experimental Treatment
Non-Treatment Group
65 Total Participants · 2 Treatment Groups
Primary Treatment: Vitamin D · Has Placebo Group · N/A
Age 18 - 40 · Female Participants · 4 Total Inclusion Criteria
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