With the outbreak of the corona pandemic, immune boosting has become a popular concept.

Recently, a 35-year-old male approached the hospital, complaining of inability to eat, and breathlessness. On evaluation, he was found to have a combination of severe liver and kidney failure. While his medical history was being studied, he admitted to preparing his own concoction of herbs and powders and consuming it, to prevent corona infection. A similar episode relating to a manufacturer of Ayurveda preparations was reported two months ago; he had consumed a remedy apparently to fight corona but succumbed to it.

Vitamins, probiotics, anti-oxidants, alternate medicines and food supplements are all marketed as immune boosters. The estimated global market in 2019 was around $133 billion. Products have been widely promoted on the internet through blogs, health news and commercial advertisements. And now it must have jumped manifold. What is the evidence of their benefit?

According to the Harvard Medical School, there is no scientific meaning to the word immune boosting. Basically there are three components to immunity or fighting of an infection: The first is through the intact skin, airway lining or the mucous membrane. The second is the innate immunity in the form of chemicals and white cells, and the third is the production of antibodies and lymphocytes. The most accepted and proven way of inducing immunity against a specific infection is vaccination. Vitamins and other nutrients help only when there is a deficiency.

Pitfalls aplenty

What is the danger of immunity-boosting supplements?

They could result in your dropping guard against the virus — in terms of being lax with the face mask, hand-washing and social distancing, which are more helpful in protecting one from catching the bug.

Such supplements give a false sense of security. This was shown scientifically in the case of influenza. In Australia, some people following naturopathy avoided the vaccine, leading to dire consequences. It has happened in the US also for other preventable diseases. Secondly, the side effects of some of them, at least in high doses, include making one sick. Many supplements have not been analysed routinely.

The FDA has warned about the presence of heavy metals in some of the herbal preparations and periodically bans them. Chinese regulatory authorities too have come down on some preparations sold in China for boosting immunity against the coronavirus. And finally, you can use the money you spend on them for something you enjoy. According to Yale university, immune boosting is a bit of a racket without scientific justification.

In India, traditionally we believe in strengthening the immune system. The ministry of Ayush has issued guidelines with special reference to coronavirus in various systems, including Naturopathy, Ayurveda, Unani, Homeopathy, Siddha, Yoga, etc. The ministry has also warned against claiming any cure for the coronavirus. The food safety organisation FSSAI regulates supplements and food products but does not question the claims of immune boosting.

The single most important cause behind catching the virus is exposure to it and the viral load. It is best prevented by physical distancing, hand-washing and wearing of masks.

General health determines the outcome in all diseases. Why some apparently healthy people succumb to corona is not known. The over-reaction of the immune system with release of cytokines and clotting produces death. It is a paradox that a drug like dexamethasone, which quietens the immune system, has reduced deaths in corona.

So, what is the final answer? A healthy lifestyle, balanced food with special attention to vegetables and fruits, ideal body weight, adequate sleep, minimising stress and lastly moderation in alcohol and avoiding smoking is the gold standard to follow.

The writer is Director, Department of Nephrology, MIOT Hospital, Chennai. Views are personal