(NaturalNews) Researchers from the University of South Carolina (USC) recently conducted a study that found a clear connection between low vitamin D levels and some of the worst and most aggressive forms of breast cancer. Particularly in women with darker skin, those deficient in vitamin D were found to be eight times more susceptible to malignant breast cancer than are women with higher levels.
For the study, Susan Steck, Ph.D., M.P.H., and her colleagues from USC evaluated 107 women who had been diagnosed with breast cancer within the previous five years. Forty-seven of the women were Caucasian while the other 60 were African-American. All women provided blood samples to researchers who tested their levels of 25-hydroxyvitamin D (25-OH-D).
They found that women with triple-negative breast cancer -- meaning the tumors contain no estrogen, progesterone, or HER2 receptors -- had the lowest blood serum levels of vitamin D. Triple-negative breast cancer is now widely recognized as one of the worst and most aggressive breast cancers, since it spreads easily and quickly.
Additionally, roughly 60 percent of the African-American women that participated in the study were vitamin D deficient, in contrast to roughly 15 percent of Caucasian women. Darker skin is not as receptive to the sun's ultraviolet rays -- the rays that produce vitamin D in the skin -- which is why researchers believe there is a large disparity between the two groups.
"We know that darker skin pigmentation acts somewhat as a block to producing vitamin D when exposed to sunlight, which is the primary source of vitamin D in most people," Steck is quoted as saying to MedPage Today. "We think it may be important to [sic] for doctors to monitor the vitamin D blood levels of their patients, especially among African-American patients."
When sunlight exposure is not enough, supplementing with vitamin D3 is the next best option. Some doctors recommend taking upwards of 10,000 international units (IU) or more per day of vitamin D as part of a healthy lifestyle.