Mumbai: Immune-boosting supplements such as vitamin C, vitamin D and zinc do not lessen the chances of dying from Covid-19, a new review by the researchers at the University of Toledo, Ohio has found. The researchers reviewed 26 peer-reviewed studies from around the globe that included more than 5,600 hospitalised Covid-19 patients and their analysis found no reduction in mortality for those being treated with vitamin D, vitamin C or zinc compared to patients who did not receive one of those three supplements.

Covid-19 patients have been widely prescribed with such immune boosting supplements during their treatment. “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. That hasn’t been shown to be true,” Dr Azizullah Beran, the lead author of the paper was quoted in a media release. Beran is an internal medicine resident at The University of Toledo College of Medicine and Life Sciences.

The paper showed that treatment with vitamin D may be associated with lower rates of intubation and shorter hospital stays, but the researchers noted that more rigorous study is needed to validate that finding. Vitamin C, usually perceived as harmless, inexpensive, with potential benefits in various respiratory infections and zinc, a trace element, were not associated with shorter hospital stays or lowering the chance a patient would be put on a ventilator, said the study published in the peer reviewed Clinical Nutrition ESPEN- an official publication of the European Society for Clinical Nutrition and Metabolism (ESPEN).

According to the authors, their paper predominantly looked at patients who were already sick and hospitalised with Covid when given the supplements, but they also did analyse a small number of individuals who had been taking vitamin D prior to contracting the virus. “No significant difference in the mortality rate of that population either,” the authors noted.

Echoing the findings of the study, internal medicine specialist Dr Anita Mathew from Fortis Hospital said that supplements do not play any role in reducing or preventing the severity of the infection or reducing mortality.

“They however help during the convalescence period while the patient is recovering,” said Mathew. “Put simply, our body stores stocks of nutrients which get rapidly utilised during the illness. A short course of these supplements helps in replenishing the nutrient stocks in the body,” she said.

According to Mathew, one must not assume that the supplements may help them from switching to moderate category from severe Covid, or help in avoiding the infection.

The authors of the study also noted that 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. Thus, patients must not take these supplements thinking they are protective against Covid-19.

Immunologist Dr Vineeta Bal from the Indian Institute of Science Education and Research (IISER), Pune called the supplements “pointless prescriptions” during Covid. “These so-called nutraceuticals have no role to play in the course of Covid. In general, let’s say if there is an elderly patient who has low absorption of nutrients, in such a situation, the supplements do have a role to play” she said.

According to Bal, often patients insist on these supplements from doctors. “But it’s the responsibility of the doctors to prescribe judiciously,” she said.