Supplements & Covid-19

There has been a high demand for supplements in the current scenario. Without any cure for the virus outbreak, people are increasingly relying on supplements to prevent or treat symptoms of Covid 19 infection. Vitamin D, C, Zinc and many more have been prescribed or procured over the counter from the start of the pandemic, but the real question that arises is, do they really work?

Let's get an insight on some of the most commonly used supplements:

Vitamin D

Also called the sunshine vitamin, it is a substance that the body produces only when exposed to sun direct sunlight. The prevalence of vitamin D deficiency in India is as high as 95% as stated by some sources(1).The active form of Vitamin D, calcitriol, has been seen to enhance the immune response in people. In a cross sectional study of the US population, it was observed that people with vitamin D deficiency had a significantly higher occurrence of upper respiratory tract infections(2). It’s been observed that people who are lab tested deficient of vitamin D, are at a higher risk of being infected compared to those who have proper stores. It can be noted that increased serum vitamin D levels above 50 ng/ml may have a beneficial effect on reducing/preventing the severity of various viral diseases including Covid-19(3).

The daily requirement of the Vitamin D for adults is 600 IU. Supplementation is advisable only for people with a confirmed deficiency (through a blood test). Vitamin D is a fat soluble vitamin, and the body ends up storing it. Excessive intake can have its consequences and can cause calcification of soft tissues like the lungs, kidneys and heart. Instead, we advocate following lifestyle strategies like daily 20 minutes of sun exposure for avoiding vitamin D deficiency and ensuring a well balanced diet to live a healthy life(4).

Food sources of vitamin D: unless the food is fortified with Vitamin D, there is no food naturally rich in it. The active form of this vitamin is almost exclusively obtained from exposure to sunlight.

Conclusion: If someone has a deficiency a supplement is a must, but taking it without knowing the blood levels can cause toxicity.

Vitamin C

Vitamin C also called ascorbic acid is a water soluble vitamin. It has antioxidant properties and has been seen to help fight common cold (5) (6). It has been observed that vitamin C supplements on regular consumption have lowered the severity and duration of cold by 8% in adults and 15% in children (7).

In the past outbreak of SARS‐CoV‐1 in 2003, the use of vitamin C, an essential micronutrient for humans and free radical scavenger, was suggested as a nonspecific treatment for severe viral respiratory tract infections (8).But in the present outbreak there are limited studies that support the same benefits towards Covid 19.

The daily need of vitamin C for adults is 40 mg/day, and normally people end up having a 1000 mg/day through supplements. As it’s a water soluble vitamin the excess is simply excreted from the body through urine. Taking a dose above 1000mg/day for a prolonged period of time can lead to gastric disturbance like nausea, abdominal cramps and diarrhoea. It can also cause a nutrient drug interaction with anticoagulation therapy in heart patients (blood thinners).

Food sources of Vitamin C: Indian gooseberry (amla), guava,drumstick leaves, lime and capsicum are some of the rich dietary sources.

Conclusion: Vitamins C may have an effect on common cold but there are no reliable scientific resources supporting the claim that taking vitamin C supplements has benefits for Covid 19 outcomes.


Zinc is a trace element (metal) important for normal growth, DNA synthesis, cell division and immunity. A deficiency can have an impact on the human immune system. Studies showed that intake of zinc supplements can reduce the duration of common cold (9). But research needs to be done in order to understand its effect on Covid 19.

The daily recommended intake of Zinc is 8 mg/day for women and 11 mg/day for men which can be met through proper nutrition. High intake of zinc through supplements can show signs of nausea, vomiting and fever. If an intake above 40mg/day is had this can lead to decrease in copper stores and reduce immune function (10).

Food sources of zinc:

- Plant food sources: Whole grain, kabuli chana, pumpkin seeds, nuts

- Animal food sources: Oysters, red meat, eggs, milk

Conclusion:There are no reliable scientific resources supporting the claim that taking zinc supplements has benefits for Covid 19 outcomes.

Omega 3 Fatty Acid

Omega 3 fatty acid is anti-inflammatory in nature. On being affected with Covid 19 the body produces immune regulators (cytokines) that are inflammatory in nature. CRP known as C - reactive protein is an inflammatory mediator produced in the liver in response to inflammation. It has been observed that these supplements can reduce inflammation in Covid 19 patients (11). However more research needed to determine the same.the daily intake for omega 3 fatty acid for males is 1.6g and females is 1.1 g.

An overuse of these supplements has seen to increase blood sugar levels in diabetes patients over a period of 8 weeks (12). It has also been seen that excess fish oil intake leads to inhibiting blood clot formation causing nose and gum bleeding.

Food sources of Omega 3 fatty acids:

- Plant food sources: Flax seeds, walnuts, soybean oil, canola oil

- Animal food sources: Mackerel, salmon, tuna, sardines

Conclusion: There are no reliable scientific resources supporting the claim that taking omega 3 fatty acid supplements has benefits for Covid 19 outcomes.


It is a non-metallic element that has anti-oxidation properties, needed for proper thyroid function and aids in boosting the immune system. It has been observed that selenium deficiency can lead to oxidative stress and hyper inflammation seen in critical illness, and its deficiency is found to be associated with the severity of Covid-19 disease (13). Its daily requirement is 40 μg/day for adults. Selenium supplement at an appropriate dose may help in supporting Covid 19 therapies, but more evidence is needed for the same. Excess intake can lead to nausea, hair fall, brittle nails, dermatitis and mottling of teeth.

Food sources of Selenium:

- Plant food sources: Whole grains, nuts, soy, beans

- Animal food sources: Pork, chicken, fish, egg

Conclusion: One can meet the daily requirements of selenium through diet hence a supplement won't be needed unless one is deficient.


Iron deficiency anemia is very common in India, especially in women of reproductive age. According to UNICEF 40% of the girls are anemic. Iron supplementation is only recommended if a diagnosis of anemia has been made through a blood test. Otherwise, Iron can be sourced through nutrition.

In case of a confirmed Covid 19 infection, iron supplements are to be stopped. Since in the case of an acute infection (Covid or otherwise), iron acts as a source of nutrition for opportunistic bacteria normally found in our gut. Iron supplements should be restarted 4 weeks after the acute illness has resolved.

Food sources of Iron: Iron is found in two forms; heme (animal source) and non-heme (plant source). Since non-heme iron is poorly absorbed, hence to enhance its absorption it's good to combine it with Vitamin C rich foods like lime, chilli, orange, amla etc.

- Non-heme iron (plant food source): Spinach, rice flakes, garden cress seeds, roasted bengal grams

- Heme iron (animal food source): Organ meat,red meat, egg, chicken

Conclusion: Having enough iron is important to avoid Covid complications. Only personas with confirmed iron deficiency should take supplements. Iron supplementation has to be stopped in case of active infection.

Vitamin E

A fat soluble vitamin that has antioxidant properties. Its immunostimulatory effects help to provide resistance to infection. Vitamin E supplements have been observed to increase high antibody response in the body (14). However when it comes to having an effect towards Covid-19 virus there is no scientific evidence stating the same.

Excess vitamin E doses more than 1000 mg can interfere with blood clotting, increasing tendency to bleed and increase the risk of hemorrhagic stroke. People on anticoagulants should be careful with this supplement intake.

Food sources of Vitamin E: unrefined vegetable oils like, olive, soybean, sunflower, nuts and wheat germ are some dietary sources.

Conclusion: being an antioxidant in nature, there is no scientific evidence that can state its effect on the precaution/cure of Covid 19 virus.

Vitamin B12

Vitamin B 12 is also known as cobalamin and is a water soluble vitamin. It has a role to play in cell division, growth and development of nervous tissues. In a study it was observed that people with B12 deficiency leading to pernicious anaemia had lower lymphocytes (immune cells) levels, and on supplementing B12 these levels rose. This proved that vitamin B12 had immunomodulatory effects on cellular immunity, and abnormalities in the immune system caused by pernicious anaemia are restored by vitamin B 12 supplements (15)(16).

Being a water soluble vitamin there are no edge cases of toxicity noticed but an over supplementation can cause neurological abnormalities, weight loss and infertility. When it comes to covid 19 infections there is no evidence that states that these supplements can help boost immune response towards this virus.

Food sources: Vitamin B 12 is found mainly in animal foods like liver, meat, eggs, milk and cheese. Vegetarians are prone to be vitamin B12 deficient as plant foods aren’t sources for the same.

Conclusion: Vitamin B12 does support immune function in people affected with pernicious anaemia, still more scientific evidence would be needed in its claim on general immunity and covid 19 recovery.


Multivitamin is a combination of different types of vitamins that can be found easily in foods. Many people use these pills as a method of prevention towards a disease. The intake of these supplements has risen up in recent years. But are these pills really effective?

It is always good to have the pill if deficient, when guided by the physician. Avoid taking more than one multivitamin product at the same time unless your doctor prescribes so. Taking similar vitamin products together can result in a vitamin overdose. As these pills contain minerals like calcium, iron, zinc, an overdose of this can have side effects.

When one can get all the nourishment through food, why have a pill? Focus more on a well-balanced diet which includes all the food groups, from cereals to vegetables to dairy products let the fads stay at bay.

About Sova Health

Sova Health is a precision nutrition platform that helps p