A new study has found that the dose of 600 International IUs of Vitamin D daily is too low for some people.
It found that African-American men living in areas with low sunlight are up to 3 1/2 times more likely to have Vitamin D deficiency than Caucasian men and should take high levels of Vitamin D supplements.
"This study shows that the current one-size fits all recommendations for 600 International Units (IU) of Vitamin D don't work," said Adam Murphy, M.D., a clinical instructor in urology at Northwestern's Feinberg School.
"Skin colour and sunlight exposure need to be considered for recommended daily allowances of Vitamin D," he stated
Vitamin D deficiency causes brittle bones and has been linked to such diseases as prostate cancer, diabetes, rheumatoid arthritis and multiple sclerosis.
African-American men have lower levels of Vitamin D because the increased melanin in darker skin blocks the ultraviolet rays necessary for the body to produce the vitamin, Murphy said.
Thus, African-American men require up to six times more sun exposure than Caucasian men to make adequate Vitamin D levels.
"It takes a dark-skinned male like myself 90 minutes three times a week to absorb enough sunlight to produce the recommended amount of Vitamin D compared to just 15 minutes three times a week for a Caucasian male," explained Murphy.
African-American men living in Chicago would need to take nearly 2,500 IU's of Vitamin D to reach normal, healthy levels, Murphy said.
The finding was presented at the American Association of Cancer Researchers Health Disparities Conference in Washington, D.C.