Impact of Vitamin D Supplementation on Inflammatory Markers in African-Americans: Results of a Four-Arm, Randomized, Placebo-Controlled Trial
Published OnlineFirst December 10, 2013; doi: 10.1158/1940-6207.Cancer Prevention Research-13-0338-T
Paulette D. Chandler 1,*,
Jamil B. Scott 2,
Bettina F. Drake 3,
Kimmie Ng 4,
JoAnn E. Manson 5,
Nader Rifai 6,
Andrew T. Chan 7,
Gary G. Bennett 8,
Bruce W. Hollis 9,
Edward L. Giovannucci 10,
Karen M. Emmons11, and
Charles S. Fuchs12
1Preventive Medicine, Brigham and Women's Hospital
2Michigan State University
3Division of Public Health Sciences, Washington University School of Medicine
4Medical Oncology, Dana-Farber Cancer Institute
5Department of Epidemiology, Harvard School of Public Health
6Children's Hospital Boston
7Division of Gastroenterology, Massachusetts General Hospital and Harvard Medical School
8Psychology, Duke University
9Heartland Assays
10Departments of Epidemiology & Nutrition, Harvard School of Public Health
11Department of Medical Oncology, Harvard School of Public Health
12Department of Medical Oncology, Dana Farber Cancer Institute and Harvard School of Public Health
↵* Corresponding Author:
Paulette D. Chandler, Preventive Medicine, Brigham and Women's Hospital, 900 Commonwealth Ave, 3rd Floor, Boston, MA, 02115, United States pchandler@partners.org
African-Americans have a disproportionate burden of inflammation-associated chronic diseases such as cancer and lower circulating levels of 25-hydroxyvitamin D [25(OH)D]. The effect of vitamin D3 (cholecalciferol) supplementation on inflammatory markers is uncertain. We conducted a randomized, double-blind, placebo-controlled trial of supplemental oral vitamin D (Placebo; 1,000; 2,000; or 4,000 IU/day of vitamin D3 orally for 3 months) in 328 African-Americans (median age, 51 years) of public housing communities in Boston, MA who were enrolled over 3 consecutive winter periods (2007-2010). Change from 0 to 3 months of plasma levels of 25(OH)D, high-sensitivity C-reactive protein (CRP), interleukin (IL)-6, interleukin (IL)-10, and soluble tumor necrosis factor alpha receptor type 2 (sTNF-R2) in 292 (89%) participants were measured.
Overall, no statistically significant changes in CRP, IL-6, IL-10, and sTNF-R2 were observed after vitamin D supplementation period. Baseline CRP was significantly inversely associated with baseline 25(OH)D level (p<0.001) in unadjusted and adjusted models. An interaction between baseline 25(OH)D and vitamin D supplementation was observed for outcome change in log CRP (Month 3-Month 0) (p for interaction=0.04). Within an unselected population of African-Americans, short-term exposure to vitamin D supplementation produced no change in circulating inflammatory markers. This study confirms the strong independent association of CRP with 25(OH)D status even after adjusting for BMI. Future studies of longer supplemental vitamin D3 duration are necessary to examine the complex influence of vitamin D3 on CRP and other chronic inflammatory cytokines for possible reduction of cancer health disparities in African-Americans.
Comment by VitaminDWiki
Doubt that very many of the African-Americans in that short of time, without a loading dose, got to a useful amount (>30 ng) of vitamin D in their blood.
Would most likely have reduced inflammation markers if any of the following:
- Had started with a loading dose of >300,000 IU
- Had 2X the time: 3 months ==> 6 months
- Had 2X the dose: 4,000 IU ==> 8,000 IU
See also VitaminDWiki
- Overview Dark Skin and Vitamin D
- Many healthy African Americans got above 33 ng with 4,000 IU of vitamin D – RCT March 2014 another publication based on this same study
- Extra 4,000 IU daily raised the vitamin D levels of blacks to that of whites – July 2012
but it took 2 months of 4,000 IU of vitamin D to get blood levels high enough to start to be of any use
The dashed line is the average for African Americans