The Effect of Vitamin D Supplementation on Glucose Metabolism in Non-Diabetic African American Adults
AVIS
1 other identifier
interventional
48
1 country
1
Brief Summary
Type 2 diabetes is more common among African Americans than Caucasians. African Americans are also at a higher risk for lower levels of vitamin D compared to other ethnic groups. The investigators don't yet know if there is a connection between not having enough vitamin D and type 2 diabetes in African Americans. Researchers have found that the less vitamin D Caucasians had the higher the chance they would have type 2 diabetes but it is less clear if this is the case for African Americans. The investigators want to better understand how vitamin D status and diabetes risk are linked in African Americans. Also, the investigators want to see if supplementation with vitamin D will improve your blood pressure, blood sugar, \& insulin. All of these are in some way related to diabetes. The investigators want to measure changes in blood sugar \& blood pressure in people who do not have diabetes with the hope of learning new information to help treat those that do have diabetes. The investigators hypothesize that vitamin D status is related to diabetes risk measured by hemoglobin A1c (a test of glucose level over time), fasting glucose and insulin in non-diabetic African American adults and that body weight status may affect vitamin D status in response to vitamin D supplements compared to placebo.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P25-P50 for not_applicable type-2-diabetes
Started Jan 2010
Shorter than P25 for not_applicable type-2-diabetes
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
Study Start
First participant enrolled
January 1, 2010
CompletedPrimary Completion
Last participant's last visit for primary outcome
May 1, 2010
CompletedStudy Completion
Last participant's last visit for all outcomes
May 1, 2010
CompletedFirst Submitted
Initial submission to the registry
June 4, 2010
CompletedFirst Posted
Study publicly available on registry
June 10, 2010
CompletedJune 10, 2010
June 1, 2010
4 months
June 4, 2010
June 9, 2010
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Fasting glucose level before, mid-way through, and after the vitamin D3 supplement or placebo trial.
16 weeks
Secondary Outcomes (1)
Serum 25-OH D levels in response to vitamin D3 supplement or placebo across a range of adiposity
16 weeks
Study Arms (2)
Vitamin D3 supplement
ACTIVE COMPARATOR60,000 IU vitamin D3 oral supplement provided every four weeks at weeks 0, 4, 8, and 12 in the form of one 50,000 and two 5,000 IU vitamin D3 supplements in gelcap form.
Sugar Pill
PLACEBO COMPARATORInactive placebo tablets identical in appearance to the active comparator provided every four weeks at weeks 0,4,8,and 12.
Interventions
1 gelcap of 50,000 IU vitamin D3 plus 2 gelcaps of 5,000 IU vitamin D3 each; a total of 60,000 IU vitamin D3 dosed four weeks apart at weeks 0, 4, 8, and 12 of the 16 week study.
The inactive comparator dose provided was identical in appearance to the active comparator but contained no vitamin D3
Eligibility Criteria
You may qualify if:
- African American by self-report
- In good health
You may not qualify if:
- Diagnosis of diabetes
- Health problems/medication affecting calcium and/or vitamin D metabolism
- Current use of vitamin/mineral/herbal/nutritional supplements
- Inability to swallow pills
- Pregnancy
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (1)
Medical College of Georgia
Augusta, Georgia, 30912, United States
Related Publications (5)
Liu E, Meigs JB, Pittas AG, McKeown NM, Economos CD, Booth SL, Jacques PF. Plasma 25-hydroxyvitamin d is associated with markers of the insulin resistant phenotype in nondiabetic adults. J Nutr. 2009 Feb;139(2):329-34. doi: 10.3945/jn.108.093831. Epub 2008 Dec 23.
PMID: 19106328BACKGROUNDPittas AG, Dawson-Hughes B. Vitamin D and diabetes. J Steroid Biochem Mol Biol. 2010 Jul;121(1-2):425-9. doi: 10.1016/j.jsbmb.2010.03.042. Epub 2010 Mar 18.
PMID: 20304061BACKGROUNDVoidonikola PT, Stamatelopoulos KS, Alevizaki M, Kollias GE, Zakopoulos NA, Lekakis JP, Anastasiou E, Theodorakis MJ, Pittas AG, Papamichael CM. The association between glycemia and endothelial function in nondiabetic individuals: the importance of body weight. Obesity (Silver Spring). 2008 Dec;16(12):2658-62. doi: 10.1038/oby.2008.431. Epub 2008 Oct 9.
PMID: 18846051BACKGROUNDLiu E, Meigs JB, Pittas AG, Economos CD, McKeown NM, Booth SL, Jacques PF. Predicted 25-hydroxyvitamin D score and incident type 2 diabetes in the Framingham Offspring Study. Am J Clin Nutr. 2010 Jun;91(6):1627-33. doi: 10.3945/ajcn.2009.28441. Epub 2010 Apr 14.
PMID: 20392893BACKGROUNDZhu H, Guo D, Li K, Pedersen-White J, Stallmann-Jorgensen IS, Huang Y, Parikh S, Liu K, Dong Y. Increased telomerase activity and vitamin D supplementation in overweight African Americans. Int J Obes (Lond). 2012 Jun;36(6):805-9. doi: 10.1038/ijo.2011.197. Epub 2011 Oct 11.
PMID: 21986705DERIVED
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Intervention Hierarchy (Ancestors)
Study Officials
- STUDY DIRECTOR
Yanbin Dong, MD, PhD
Augusta University
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- PARTICIPANT, INVESTIGATOR
- Purpose
- PREVENTION
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
Study Record Dates
First Submitted
June 4, 2010
First Posted
June 10, 2010
Study Start
January 1, 2010
Primary Completion
May 1, 2010
Study Completion
May 1, 2010
Last Updated
June 10, 2010
Record last verified: 2010-06