[ Back to EurekAlert! ]

PUBLIC RELEASE DATE:
20-Sep-2011

[ | E-mail ] Share Share

Contact: Jeremy Moore
Jeremy.Moore@aacr.org
267-646-0557
American Association for Cancer Research
@aacr

African-American men living in poor sunlight areas at risk for vitamin D deficiency

WASHINGTON, D.C. -- African-American men living in low sunlight areas are more likely to experience vitamin D deficiency than European-American men living in the same environment. Researchers believe that these findings should change recommendations for daily intake of vitamin D.

"This study shows that across the board vitamin D recommendations just won't work for everybody," said Adam B. Murphy, M.D., M.B.A., clinical instructor in the department of urology at Northwestern University Feinberg School of Medicine, who reported the study at the Fourth AACR Conference on The Science of Cancer Health Disparities, held Sept. 18-21, 2011, in Washington, D.C.

"With so many diseases linked to low levels of vitamin D, we should have more stratified recommendations to consider groups within the population instead of making monolithic suggestions," he added.

Researchers evaluated the marker for vitamin D - the 25 hydroxyvitamin D level (25-OH D level) - in 492 men aged 40 to 79 years who lived in Chicago, a low ultraviolet radiation (UVR) part of the country. Of that group, 93 percent of African-American men and 69.7 percent of European-American men were vitamin D deficient; having 25-OH D levels of less than 30 ng/mL.

Results showed that vitamin D levels were low in African American men, those with lower income and those with higher body mass index. Low sunlight exposure is a known factor in lower levels of vitamin D, but researchers found that African American men still had lower levels of vitamin D in sunnier seasons.

Murphy attributes low vitamin D levels to the composition of African-American skin, which contains more of the pigment melanin than lighter skin. When UVR light hits the skin cells, it reacts with the molecule 7-dehydrocholesterol to begin the production of vitamin D, which is then further processed by the body to make active vitamin D. In African-Americans, though, melanin blocks UVR rays from being absorbed, thus reducing the amount of vitamin D naturally produced.

Vitamin D deficiency has been linked to multiple diseases, including breast cancer, prostate cancer, diabetes, rheumatoid arthritis and multiple sclerosis, which is why Murphy believes it is essential to adjust recommendations to reflect differences between African Americans and European-Americans.

"Because we have a lot of special populations in the United States - people who have darker skin, people who cover their skin for religious reasons and people who live in poor sunlight environments - there shouldn't be uniform vitamin D recommendations for the entire population," he said.

###

Follow the AACR on Twitter: @aacr #aacr

Follow the AACR on Facebook: http://www.facebook.com/aacr.org

The mission of the American Association for Cancer Research is to prevent and cure cancer. Founded in 1907, the AACR is the world's oldest and largest professional organization dedicated to advancing cancer research. The membership includes 33,000 basic, translational and clinical researchers; health care professionals; and cancer survivors and advocates in the United States and more than 90 other countries. The AACR marshals the full spectrum of expertise from the cancer community to accelerate progress in the prevention, diagnosis and treatment of cancer through high-quality scientific and educational programs. It funds innovative, meritorious research grants, research fellowships and career development awards. The AACR Annual Meeting attracts more than 18,000 participants who share the latest discoveries and developments in the field. Special conferences throughout the year present novel data across a wide variety of topics in cancer research, treatment and patient care. The AACR publishes seven major peer-reviewed journals: Cancer Discovery; Cancer Research; Clinical Cancer Research; Cancer Epidemiology, Biomarkers & Prevention; Molecular Cancer Therapeutics; Molecular Cancer Research; and Cancer Prevention Research. AACR journals received 20 percent of the total number of citations given to oncology journals in 2010.



[ Back to EurekAlert! ] [ | E-mail Share Share ]

 


AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.