A new study from Mass General Brigham indicates vitamin D may help reduce the risk of long COVID. Researchers analyzed 1,747 adults recently infected with COVID-19, plus 277 household contacts, assigning them either high-dose vitamin D3 or a placebo for four weeks.
The trial showed no impact on acute infection severity or transmission to household members. However, participants who adhered closely to the regimen reported fewer lingering symptoms.
About 21% in the vitamin D group had ongoing symptoms eight weeks post-infection, compared to 25% in the placebo group. Dr. JoAnn Manson, the study’s senior author, said vitamin D's role in regulating inflammation may explain its potential effect on long-term outcomes.
Researchers emphasize the findings are preliminary. Larger trials are planned to confirm whether vitamin D can prevent or treat long COVID. Supplementation ideally should begin early after diagnosis.
