Can Black Americans Reduce or Eliminate Racial Health Disparities by Getting More Sun Exposure?

Abstract

It is becoming well understood that insufficient sun exposure is a risk factor for many adverse health effects. Increased adverse health effects such as cancers and cardiovascular disease have been quantified with respect to measured levels of vitamin D, a marker for sun exposure. Most acquired vitamin D [measured as 25(OH)D level] is a result of ultraviolet radiation from sun exposure. Because of higher levels of melanin in the skin, individuals with darker skin obtain less vitamin D and other beneficial sun-produced biomolecules such as nitric oxide from a given amount of sun exposure. It is the purpose of this paper to report the published observed 25(OH)D levels in Black Americans and the correlated levels of adverse health effects. Our conclusion is that insufficient sun exposure is a major component of the observed health disparities between Black and White Americans, and that Black Americans can significantly attenuate these disparities by having enough additional sun exposure to raise their 25(OH)D levels to 30 ng/mL.

Are Vitamin D Supplements an Adequate Substitute for Sun Exposure?

“…For many years, vitamin D has been commonly assumed to be the only health benefit of sun exposure. More recently, there has been greater awareness of the diversity of other mediators released in response to sun exposure, suggesting that the beneficial effects of sun exposure may be mediated by multiple sun-induced molecules in addition to vitamin D 1,2,9,12 .…”

“…Nitric Oxide. The 1998 Nobel Prize in Medicine was awarded for the discovery of nitric oxide as an important signaling molecule in the cardiovascular system that protects the heart, stimulates the brain and kills bacteria 9 . In 2009, it was discovered that sun exposure converts nitrogen derivates stored in the skin to nitric oxide which is mobilized to the circulatory system and causes a significant decrease in blood pressure 1,2,9,[13][14][15][16][17] .…”

“…Starting at the beginning of the 21st century, scientists around the world began discovering correlations between increased risks of a wide variety of diseases and low levels of 25(OH)D 1,2 . They also began discovering a diversity of mediators produced in the body by sun exposure, indicating that some of the health benefits of sun exposure may not be attributable to vitamin D 1,2,9 .…”

“…Numerous scientific studies over the past 20 years have correlated low levels of 25(OH)D with dramatically increased risk of premature death and a large number of diseases and adverse conditions including hypertension, cardiovascular disease, stroke, breast cancer, colorectal cancer, metabolic syndrome, type 2 diabetes, obesity, multiple sclerosis, type 1 diabetes, rheumatoid arthritis, Alzheimer's disease, autism, schizophrenia, asthma, preterm birth, maternal mortality, myopia and COVID-19 1,2,9,11 . The adverse health effects of insufficient sun exposure have grown to the point that insufficient sun exposure has become a significant public health problem 1 .…”

“…Studies in the last decade indicate that low levels of 25(OH)D may be responsible for 340,000 preventable deaths per year in the United States 1 , making low levels of 25(OH)D the nation's second largest public health problem after tobacco with its 480,000 preventable deaths per year 10 . This enormous burden of disease and death falls disproportionately on Black Americans because the larger amount of melanin in their skins, which developed by evolution of their African ancestors under the powerful equatorial sun, is not suited for the weaker sun of America and absorbs more of the sun's rays than the lesser amount of melanin in the skins of White Americans 9,11 .…”