A study of men in Chicago found that low vitamin D levels were more common in African-American men than in European-American men. These results were presented at the Fourth AACR Conference on The Science of Cancer Health Disparities, held September 18-21 in Washington DC.
Vitamin D is important for bone health, and some research suggests that it may also reduce the risk of certain types of cancer. A role for vitamin D in cancer prevention has not yet been firmly established, however, and research on this topic continues. Vitamin D can be produced in the skin in response to ultraviolet B (UVB) radiation from the sun or obtained from dietary sources. Few foods naturally contain large amount of vitamin D, but vitamin D can be obtained from fatty fish such as salmon, fortified foods such as milk, and dietary supplements.
The level of vitamin D that is optimal for health is still a matter of debate, but it’s clear that some segments of the population are more likely than others to have levels that may be insufficient. People who are at increased risk of having low vitamin D levels include breastfed infants, older adults, people with limited sun exposure, people with dark skin, people who are obese or who have undergone gastric bypass surgery, and people with a reduced ability to absorb fat in the gut (such as those with Crohn’s disease).
To explore blood vitamin D levels among men in a low ultraviolet radiation part of the country (Chicago), researchers conducted a study among 492 men between the ages of 40 and 79. A low vitamin D level was defined as a level of 25-hydroxyvitamin D [25(OH)D] less than 30 ng/ml.
Low vitamin D levels were detected in 93% of the African American men and 70% of the European American men. People with darker skin tend to produce less vitamin D in their skin than people with lighter skin. The researchers note that recommendations regarding vitamin D intake may need to vary by factors such as skin color and sun exposure.
Because of the link between sun exposure and skin cancer, organizations such as the American Academy of Dermatology recommend getting vitamin D through dietary supplements rather than through sun exposure. Dietary supplements can provide an identical form of vitamin D without the skin cancer risk. It’s also important for people to realize that at high latitudes (regions farther from the equator, including the northern part of the United States), sun exposure does not produce any vitamin D during winter months.
Reference: American Association for Cancer Research (AACR) Press Release. African-American Men Living in Poor Sunlight Areas at Risk for Vitamin D Deficiency. September 20, 2011.