After being revealed 94% of United Kingdom doctors who died from COVID-19 infections were black, Asian, and minorities, a study is exploring whether vitamin D deficiency is a root cause of vulnerability.

"These figures are extremely disturbing," British Medical Association Chairman Dr. Chaand Nagpaul, told the BBC. "This is a figure that cannot be explained on pure statistical variation."

While health experts agree low levels of vitamin D can increase risk of severe COVID-19 cases, specifically lung infections, the theory would require more empirical data through clinic study, ABC news reported.

"There are likely to be many different reasons black or Asian people are more likely to suffer from COVID-19 infection," University of Liverpool pharmacologist Andrew Hill, M.D., told ABC News.

"More densely populated housing, higher prevalence of diabetes and hypertension, more likely to use public transport and also potentially low Vitamin D levels. I doubt that Vitamin D deficiency is the only reason for the higher risks of COVID-19 infection."

Vitamin D deficiencies tend to require "people with darker skin may need more sunlight to get the recommended levels of vitamin D," per the report.

"There are a lot of diseases in which worse outcomes are associated with vitamin D deficiency, yet almost none has shown that restoring vitamin D leads to improved outcomes," Atlanta's Emory University professor Dr. Carlos del Rio told ABC News. "Bottom line, association does not mean causation."

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