Vitamin D May Help Lower Risk of Severe Flu Complications

New research analyzing 36,258 UK Biobank participants found people with severe vitamin D deficiency (below 15 nmol/L) had a 33% higher hospitalization rate for respiratory tract infections than those with levels of 75 nmol/L or higher, and each 10 nmol/L increase was linked to a 4% lower hospitalization rate.

Vitamin D has been linked in new research to lower risk of severe reactions to the flu. The study examined health records from 36,258 people who are part of the UK Biobank. Researchers reported higher hospitalization rates for respiratory infections among those with severe vitamin D deficiency. The report appears as flu activity remains high in the U.S., driven in part by the subclade K variant. Key findings: - Researchers analyzed data from 36,258 UK Biobank participants. - Severe vitamin D deficiency (under 15 nmol/L) was associated with a 33% higher rate of hospitalization for respiratory tract infections compared with levels of 75 nmol/L or higher. - Each 10 nmol/L increase in vitamin D was associated with a 4% lower hospitalization rate for respiratory infections. - The analysis was observational, meaning it identified an association rather than proving a cause-and-effect link. - Experts quoted in the article noted vitamin D’s role in immune function and reiterated that vaccination and other established prevention measures remain central to flu control. Summary: The findings add to earlier research connecting low vitamin D levels with greater risk of respiratory infection, particularly among those with severe deficiency. Because the study is observational, it cannot establish causation. Undetermined at this time.