A simple step could help millions of people reduce their risk of heart disease, according to new research: make sure to get enough vitamin D. The new research elucidates linkages between skin pigmentation, vitamin D, and indicators of cardiovascular health. Combined with evidence from previous research, the new study suggests vitamin D deficiency could contribute to the high rate of heart disease among African Americans.
“More darkly-pigmented individuals may be at greater risk of vitamin D deficiency, particularly in areas of relatively low sun exposure or high seasonality of sun exposure,” said S. Tony Wolf, PhD, a postdoctoral fellow at the Pennsylvania State University and the study’s lead author. “These findings may help to explain some of the differences that we see in the risk for developing blood vessel dysfunction, hypertension, and overt cardiovascular disease between ethnic groups in the United States. Although there are many factors that contribute to the development of hypertension and cardiovascular disease, vitamin D supplementation may provide a simple and cost-effective strategy to reduce those disparities.”
Your need for vitamin D supplementation depends on a variety of factors, Wolf noted. These include where you live, how much time you spend in the sun, your skin pigmentation, and your age.
Wolf presented the research at the American Physiological Society annual meeting during the Experimental Biology (EB) 2021 meeting.
Melanin, which is more concentrated in darker skin, is known to inhibit the process our bodies use to produce vitamin D when exposed to sunlight. As a result, darkly pigmented people may make less vitamin D, which could potentially lead to vitamin D deficiency.
18 healthy adults of varying skin tones participated in the study. Wolf and colleagues measured skin pigmentation, vitamin D, and the activity of nitric oxide in the small blood vessels beneath the skin of each participant. Nitric oxide is important for blood vessel function, and reduced nitric oxide availability is thought to predispose an individual to the development of cardiovascular disease or hypertension. Previous studies indicate that vitamin D helps to promote nitric oxide availability.
According to the results, study participants with darker skin had lower levels of vitamin D and lower nitric oxide availability. Additionally, the scientists found that lower levels of vitamin D were related to reduced nitric oxide-mediated blood vessel function. The findings align with those of a separate study by the same research group, which found that vitamin D supplementation improved blood vitamin D levels and nitric oxide-mediated blood vessel function in otherwise healthy, young African American adults.
“Vitamin D supplementation is a simple and safe strategy to ensure vitamin D sufficiency,” said Wolf. “Our findings suggest that promoting adequate vitamin D status in young, otherwise healthy adults may improve nitric oxide availability and blood vessel function, and thereby serve as a prophylactic to reduce risk of future development of hypertension or cardiovascular disease.”