Race and Covid-19 Outcomes
It has been widely reported that nonwhite racial groups have been disparately impacted by COVID-19, including up to a three-fold higher risk of testing positive for infection as compared to whites, as well as a larger percentage needing hospitalization, and even dying from the infection. This has been true for African-Americans, Latinos, Asian-Americans, and Native Americans within the US; and similar racial disparities have been observed in other countries [1-11].
Some of the explanation for these disparate impacts doubtless lies in societal factors, including worse health and healthcare among low-income nonwhite minorities, more crowded households with higher rates of transmission, and greater participation of nonwhite minorities in occupations that involve extensive contact with the public (essential employees; grocery workers; transit workers; etc) [12-15].
However, anecdotal reports indicate that even wealthy, high-status African-Americans have succumbed to COVID at high rates; [16,17], and studies suggest that Vitamin D is an important biological factor that may also contribute to COVID-19 outcomes [18]. Evidence suggests a potential relationship between melanin, Vitamin D, and COVID outcomes.
Skin Color, Melanin, and Vitamin D
It has been known for decades that African-Americans have, on average, lower levels of Vitamin D than whites [20-23]. This difference appears largely due to skin melanin (pigment) absorbing the UV-B rays that are required for the deep layers of skin to manufacture the Vitamin D precursor [24-26]. Other non-white racial groups who live in the industrialized North (eg North America and Europe) or in urban environments in the less developed South (eg Africa) also tend to have lower Vitamin D levels [27-30]. The higher levels of melanin are helpful for shielding the skin from the harmful effects of UV-B, such as skin cancer, but those same UV-B rays are needed to make Vitamin D, and if dark skin is not exposed to enough skin, Vitamin D deficiencies can occur.
The good news is that Vitamin D supplementation with capsules or softgels is very effective at increasing blood levels of Vitamin D. Higher levels of supplementation are generally needed in individuals with darker skin, but it has been shown to be safe and effective [31-35].
Skin Color and COVID
At this time, it has not been scientifically proven that low Vitamin D levels are a cause for worse outcomes to COVID infection among African-Americans or other nonwhite racial groups, nor that Vitamin D can protect us from COVID. Additionally, we do not suggest that low Vitamin D levels in nonwhite groups are the only cause of worse outcomes to COVID infection [35]. However, the evidence is strong that low levels of Vitamin D in dark-skinned individuals are a cause for worse outcomes to other respiratory infections such as the flu and pneumonia [36].
Given that dark skin predisposes people to both low levels of Vitamin D and worse outcomes to COVID, and that low levels of Vitamin D are associated with worse COVID outcomes, consensus is growing that the links between levels of melanin, Vitamin D status, and COVID outcomes are likely to be real [37-39].
REFERENCES
Price-Haygood, E. et al. 2020. Hospitalization and Mortality among Black Patients and White Patients with Covid-19. N Engl. J. Med. 382:2534.
Khunti, K. et al. 2020. Is ethnicity linked to incidence or outcomes of covid-19? The Harvard Gazette.
Pan, D. et al. 2020. The impact of ethnicity on clinical outcomes in COVID-19: A systematic review. eClinicalMedicine. 23:100404.
Ford, T. et al. 2020. Race gaps in COVID-19 deaths are even bigger than they appear. Brookings Institution. June 16, 2020.
Mineo, L. 2020. For Native Americans, COVID-19 is ‘the worst of both worlds at the same time’. The Harvard Gazette. May 8, 2020.
Barboza, T. & Poston, B. 2020. I was naive to think this couldn’t touch my family’: Pacific Islanders hit hard by the coronavirus. The Los Angeles Times. July 19, 2020.
Muñoz-Price, L. et al. 2020. Racial Disparities in Incidence and Outcomes Among Patients With COVID-19. JAMA Netw. Open. 3:e2021892.
Rentsch, C. et al. 2020. Patterns of COVID-19 testing and mortality by race and ethnicity among United States veterans: A nationwide cohort study. PLoS Med. 17: e1003379.
Baqui, P. et al. 2020. Ethnic and regional variations in hospital mortality from COVID-19 in Brazil: a cross-sectional observational study. Lancet Glob. Health. 8:e1018.
Pareek, M. et al. 2020. Ethnicity and covid-19: an urgent public health research priority. Lancet. 395:1421.
Abuelgasim, E. et al. 2020. COVID-19: Unique public health issues facing Black, Asian and minority ethnic communities. Curr. Prob. Cardiol. 45: 100621.
Uzoigwe, C. 2020. Coronavirus R number hides raised risk for minority ethnic groups. Nature. 582:341.
Ahmed, M. 2020. Black and Minority Ethnic (BAME) Alliance Against COVID-19: One Step Forward. J. Racial Ethn. Health Disparities. 7:822.
Health Equity Considerations and Racial and Ethnic Minority Groups. Centers for Disease Control, accessed October 18, 2020.
Webb Hooper, M. 2020. COVID-19 and Racial/Ethnic Disparities. JAMA. 323:2466.
Reuters Staff. Herman Cain, ex-presidential candidate who refused to wear mask, dies after COVID-19 diagnosis. July 30, 2020.
Marbella, J. & Harris, N. Maryland’s Prince George’s County is among nation’s wealthiest Black communities, but it leads state in coronavirus cases. Baltimore Sun July 9, 2020.
Meltzer, D. et al. 2020. Association of Vitamin D Status and Other Clinical Characteristics With COVID-19 Test Results. JAMA Netw. Open. 3: e2019722.
Bell, N. et al. 1982. Evidence for alteration of the vitamin D-endocrine system in blacks. J. Clin. Invest. 76:470.
Hollis, B. & Pittard, W. 1984. Evaluation of the total fetomaternal vitamin D relationships at term: evidence for racial differences. J. Clin. Endocrinol. Metab. 59:652.
Nesby-O’Dell, S. et al. 2002. Hypovitaminosis D prevalence and determinants among African American and white women of reproductive age: third National Health and Nutrition Examination Survey, 1988-1994. Am. J. Clin. Nutr. 76:187.
Harris, S. et al. 2006. Vitamin D and African Americans. J. Nutr. 136:1126.
Loomis, W. 1967. Skin-pigment regulation of vitamin-D biosynthesis in man. Science. 157:501.
Clemens, T. et al. 1982. Increased skin pigment reduces the capacity of skin to synthesise vitamin D3. Lancet. 1:74.
Rockell, J. et al. 2008. Association between quantitative measures of skin color and plasma 25-hydroxyvitamin D. Osteoporos. Int. 19:1639.
Gozdzik, A. 2008. Low wintertime vitamin D levels in a sample of healthy young adults of diverse ancestry living in the Toronto area: associations with vitamin D intake and skin pigmentation. BMC Public Health.. 8:336.
Forrest, K. & Stuhldreher, W. 2011. Prevalence and correlates of vitamin D deficiency in US adults. Nutr. Res. 31:48.
van der Meer, I. 2011. Prevalence of vitamin D deficiency among Turkish, Moroccan, Indian and sub-Sahara African populations in Europe and their countries of origin: an overview. Osteoporos. Int. 22:1009.
Mojire, R. et al.2020. Prevalence of vitamin D deficiency in Africa: a systematic review and meta-analysis. Lancet Global Health. 8:e134.
Aloia, J. et al.2005. A randomized controlled trial of vitamin D3 supplementation in African American women. Arch. Intern. Med. 165:1618.
Hall, L. et al. 2010. Vitamin D intake needed to maintain target serum 25-hydroxyvitamin D concentrations in participants with low sun exposure and dark skin pigmentation is substantially higher than current recommendations. J. Nutr. 140:542.
Garrett-Mayer, E .et al. 2012. Vitamin D3 supplementation (4000 IU/d for 1 y) eliminates differences in circulating 25-hydroxyvitamin D between African American and white men. Am. J. Clin. Nutr. 96:332.
Murphy, A .et al. 2012. Predictors of serum vitamin D levels in African American and European American men in Chicago. Am. J. Mens Health. 6:420.
Ng, K .et al. 2014. Dose response to vitamin D supplementation in African Americans: results of a 4-arm, randomized, placebo-controlled trial. Am. J. Clin. Nutr. 99:587.
Raisi-Estabragh, Z. et al. 2020. Greater risk of severe COVID-19 in Black, Asian and Minority Ethnic populations is not explained by cardiometabolic, socioeconomic or behavioural factors, or by 25(OH)-vitamin D status: study of 1326 cases from the UK Biobank. J. Public Health (Oxf). 42:451.
Aloia, J. et al. 2007. Re: epidemic influenza and vitamin D. Epidemiol. Infect. 135:1095.
Manson, JA .& Bassuk, S. 2020. Commentary. Eliminating Vitamin D Deficiency During the COVID-19 Pandemic: A Call to Action. Metabolism. 112:154322.
Kohlmeier. 2020. Avoidance of vitamin D deficiency to slow the COVID-19 pandemic. BMJ Nutrition, Prevention, & Health. 3:doi: 10.1136/bmjnph-2020-000096.
Thakkar, V. Vitamin D and Coronavirus Disparities: Supplements may promote immunity, especially in people with darker skin. Wall St. Journal. April 16, 2020.