A new study of COVID-19 hospitalisation data found that taking vitamins and supplements do not lessen the chance of COVID-19 mortality.
A meta-analysis of 26 studies that includes over 5,600 patients hospitalised with COVID-19, carried out by the University of Toledo, found that taking vitamins and supplements that aim to boost immunity like vitamin C, vitamin D, and zinc do not lessen the chance of mortality from COVID-19.
Early in the pandemic, healthcare providers tried a variety of micronutrients as potential therapies for COVID-19. More recently, vitamins and supplements have been promoted as an alternative to safe and proven vaccines as a way to combat the condition.
The paper is published in the journal Clinical Nutrition ESPEN.
Little evidence for vitamins and supplements
Dr Azizullah Beran said there’s been little evidence those strategies work, despite the enduring interest in them. “A lot of people have this misconception that if you load up on zinc, vitamin D or vitamin C, it can help the clinical outcome of COVID-19,” said Beran, an internal medicine resident at The University of Toledo College of Medicine and Life Sciences. “That hasn’t been shown to be true.”
Beran is the lead author on the new paper that significantly strengthens the emerging medical consensus that micronutrient vitamins and supplements are not an effective treatment for COVID-19.
The research team reviewed 26 peer-reviewed studies from around the globe which included data from over 5,600 hospitalised COVID-19 patients. Their analysis found no reduction in mortality for those being treated with vitamin C, vitamin D or zinc compared to patients who did not receive one of those three vitamins and supplements.
Furthermore, their analysis found that treatment with vitamin D may be associated with lower rates of intubation and shorter hospital stays, but the researchers said a more rigorous study is needed to validate that finding. Vitamin C and zinc were not associated with shorter hospital stays or lowering the chance a patient would be put on a ventilator.
Whilst the study predominately looked at patients who were already sick and hospitalised with COVID-19 when given the vitamins and supplements, researchers did analyse a smaller subset of individuals who had been taking vitamin D before contracting the virus. Again, they found no significant difference in the mortality rate of that subset either.
Ineffective against COVID-19
“It’s important for people to understand that taking a lot of these supplements does not translate into better outcomes,” said Dr Ragheb Assaly, a UToledo professor of medicine and the paper’s senior author. “The other important message is that the answer to this disease is the vaccine. Micronutrient supplements will not offset the lack of vaccination or make you not need the vaccine.”
The researchers cautioned that the study should not be interpreted as saying vitamins and supplements should be avoided but clarified that they are ineffective at preventing COVID-19 deaths.
Beran and Assaly said it’s possible that some COVID-19 patients who are malnourished or otherwise deficient in micronutrients may benefit from taking supplements, but that’s because their bodies already lack essential nutrients — not because vitamin D or vitamin C are effective against the virus.
“What we’re saying is this: If you don’t medically need these supplements, don’t take them thinking they’re protective against COVID-19,” Beran said. “They’re not going to prevent you from getting it and they’re not going to prevent you from dying.”
