Researchers at Mass General Brigham examined whether high doses of vitamin D could influence COVID-19 outcomes, including the risk of developing long COVID, a condition in which symptoms such as fatigue, shortness of breath and brain fog continue weeks or months after the initial infection<\/a>.<\/p>\n The findings were published in The Journal of Nutrition.<\/p>\n HIGHLY CONTAGIOUS VIRUS WITH NO TREATMENT SPREADING RAPIDLY THROUGH WESTERN STATE<\/a><\/p>\n The randomized clinical trial included 1,747 adults who had recently tested positive for COVID-19, along with 277 members of their households. Participants were assigned to receive either vitamin D3 supplements or a placebo for four weeks.<\/p>\n A new study suggests vitamin D may help researchers better understand and possibly prevent long COVID. (iStock)<\/p>\n Dr. JoAnn Manson, senior author of the study and a physician at Mass General Brigham, told Fox News Digital that the results point to a possible benefit<\/a> related to long-term symptoms.<\/p>\n “A key takeaway is that vitamin D supplementation looks promising for reducing the risk of developing long COVID but does not appear to affect the severity of the acute infection,” Manson said.<\/p>\n COMBINATION NASAL SPRAY VACCINE COULD PROTECT AGAINST COVID, FLU AND PNEUMONIA AT ONCE<\/a><\/p>\n Researchers found that vitamin D supplementation did not significantly change short-term outcomes such as symptom severity<\/a>, hospital visits or emergency care.<\/p>\n The study also showed no difference between the vitamin D and placebo groups in the likelihood that household contacts would contract the virus.<\/p>\n Long COVID is a condition where symptoms like fatigue, shortness of breath, and brain fog last for weeks or months after the initial infection. (iStock)<\/p>\n However, when researchers analyzed participants who closely followed the supplement regimen, they observed a possible difference in lingering symptoms.<\/p>\n CLICK HERE TO SIGN UP FOR OUR LIFESTYLE NEWSLETTER<\/a><\/p>\n About 21% of participants who took vitamin D reported at least one ongoing symptom eight weeks after infection, compared with 25% of those who received a placebo.<\/p>\n “There\u2019s been tremendous interest in whether vitamin D supplements can be of benefit in COVID, and this is one of the largest and most rigorous randomized trials on the subject,” Manson said in the press release.<\/p>\n “While we didn\u2019t find that high-dose vitamin D reduced COVID severity or hospitalizations, we observed a promising signal for long COVID that merits additional research,” she added.<\/p>\n CLICK HERE FOR MORE LIFESTYLE STORIES<\/a><\/p>\n Manson said vitamin D may influence longer-term complications because the nutrient<\/a> plays a role in regulating inflammation in the body.<\/p>\n Researchers say vitamin D may affect inflammation in the body, which could play a role in long COVID symptoms. (iStock)<\/p>\n Study limitations<\/p>\n The researchers noted several limitations in the trial. The study had to be conducted remotely during the pandemic, and participants began taking vitamin D several days after their COVID diagnosis.<\/p>\n TEST YOURSELF WITH OUR LATEST LIFESTYLE QUIZ<\/a><\/p>\n Ideally, Manson said, supplementation would begin before infection or immediately after diagnosis.<\/p>\n She added that larger studies<\/a> will be needed to confirm whether vitamin D could reduce the risk or severity of long COVID symptoms.<\/p>\n![\"Person](\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2026\/03\/woman-holding-supplements-hand.jpg\")
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