Food & Supplements : Do They Lower Risk Of Infection?

Apr 23, 2020

Today, some of the most pressing questions about health are – How can I boost my immunity? Should I take supplements? How can I avoid getting infected? And more..

Health is always on our mind and we often try different things to stay healthy. If you are healthy, you probably have a strong immune system and can fight off most infections. On the contrary, having a weakened immunity doesn’t mean you will definitely get infected/develop disease, it means that you are more likely to get infected when you come in contact with an infected person or get exposed to pathogens.

Studies prove that the immune system and lifestyle habits are interconnected but the mechanisms are fully not understood. Various studies are being conducted to learn about the effect of diet, physical activity, psychological factors etc., on immune response.  

Can good nutrition really boost the immune system? Will taking supplements help boost the immune system?

Our immune system offers protection against various diseases and infections caused by bacteria, virus, fungi etc. The immune system is not a single entity – it contains many cells (T cells, B cells, NK cells, macrophages and more). For optimal functioning of the immune system, balance and harmony is required between these immune bodies.

Most infections trigger the immune system – mostly ‘adaptive immunity’ which targets specific pathogens and kills them. The concept of ‘boosting’ immunity is to get a stronger/active immune response. Yet, the concept of boosting immunity is always controversial. 

One of the best ways to maintain immunity is to have a proper nutritious diet combined with  regular physical activity. 

Many health experts across the world are recommending a diet rich in nutrients with antiviral properties, which in turn help the immune system to fight against infections, such as coronavirus.  Let us see the properties of certain nutrients and how they help the immune system.

Also Read: Immunity Boosting Nutrients

Vitamin C

Vitamin C is an essential micronutrient which helps the immune defenses by supporting the  functioning of both the innate and adaptive immune system. The role of vitamin C in lymphocytes is less clearly understood , but it has been known that vitamin C enhances the  differentiation and proliferation of B- and T-cells , and helps swallow the pathogens that enter our body.

Vitamin C also has antioxidant activity, and can decrease the inflammation which may help the immune system. Vitamin C deficiency most likely results in impaired immunity and higher susceptibility to infections caused by any viruses, bacteria , fungi etc.

In turn, infections may also significantly impact on vitamin C levels in our body due to enhanced inflammation and metabolic requirements. Furthermore, supplementation with vitamin C may be known to be able to both prevent and treat respiratory and systemic infections.

In studies, for effectiveness against viruses that cause the infections, vitamin C may not make you any less likely to get infected  but it may help you get over the infection faster and make the symptoms less severe.

A few studies state that individuals infected with coronavirus were administered with vitamin C intravenously (as nutrient levels drastically dropped due to the inflammatory responses during the infection). They had significantly better outcomes than those who were not administered Vitamin C . However, this does not mean that supplementation of vitamin C cures the infection. 

Vitamin C is rich in guava, papaya, broccoli, kiwi fruit, oranges, red/green/yellow peppers, tomatoes , strawberries, brussels sprouts, cantaloupe, pineapple, potatoes etc.

Also Read: The Role of Your GENES in Fighting COVID-19

Vitamin D 

Vitamin D plays an important role in maintaining an adequate level of serum calcium and phosphorus. Recently, studies have also been found that vitamin D receptors exist in various cells, thus it has a biological effect on more than mineral metabolism. 

Vitamin D insufficiency affects almost 50% of the population across the globe. Vitamin D is unique because it can be made in the skin from exposure to sunlight.

Obtaining sufficient vitamin D from natural food sources (cod liver oil, egg yolk, milk, fatty fish like tuna, mackerel, salmon, etc) alone is difficult, the consumption of vitamin D from fortified foods, mushrooms, cow milk, cereals, oat meals and exposure to some sunlight are essential for maintaining a healthy vitamin D status. 

Insufficient levels of vitamin D may decrease the cell proliferation and increase cell differentiation, stop the growth of new blood vessels, and have significant anti-inflammatory effects.

According to researchers, vitamin D supplementation may aid in resistance against the respiratory infections caused by coronavirus or limit illness, particularly in adult patients. People with low levels of Vitamin D have weaker immune defenses against coronavirus. 


Zinc is an essential micronutrient that our body doesn’t make on its own. This means that we have to obtain zinc from diet and/or supplementation. Zinc plays a role in metabolism, catalyzes over more than 100 enzymes, facilitates protein folding and also helps regulate gene expression. 

Zinc deficiency is now known to be an important malnutrition problem across the globe, mostly among older adults.

Zinc supplementation may be effective for prevention of upper respiratory infection and diarrhea, and as an adjunct treatment for diarrhea in malnourished children.

Studies are being  carried out for investigating the association between the role of zinc and viral infections, as some theories state that zinc inhibits the binding of the virus to the nasal mucosa and suppresses inflammation. 


Antioxidants are mainly known to reduce the cell damage, counteract oxidative stress, to  obtain and maintain the optimal health. The sources of antioxidants are natural or artificial . certain plant based foods ( leafy vegetables, legumes, berries, fruits like watermelon, oranges, mangoes etc,  bell pepper, peas, nuts, grains etc.) are known to be rich in antioxidants. 

Antioxidants help neutralize the free radicals in our body. Free radicals are highly unstable molecules that are formed in our body during exercise, heavy workout sessions, when your body converts food into energy. Free radicals cause oxidative stress , which may damage our tissues, cells . Oxidative stress plays an important role in certain diseases like Alzheimer’s ,  certain cardiovascular diseases, diabetes and certain eye diseases. 

Oxidative stress is also seen during a cytokine storm (immune overreaction), however the association is not fully delineated. A cytokine storm is mainly seen during a viral infection, where more number of immune bodies are released to fight the infection and cause severe damages, sometimes death. In case of COVID-19 infection, acute lung damages are seen due to cytokine storm, hence the novel concept of using the immunonutrients for modulation of cytokine production has been applied, where the antioxidants, anti-inflammatory oral nutrient supplements are given to patients on a daily basis.  

There is evidence that proves that deficiencies in micronutrients alter immune response.  When it comes to fighting against the viruses, everyday precautions such as washing your hands often and avoiding meeting the sick people are key. But experts suggest that boosting your immune system via diet, may also give you an edge in staying healthy.

Genetic factors

There are certain genes that affect the levels of these micronutrients in blood,  and are likely to increase risk for deficiencies due to certain genetic variation. Mapmygenome has introduced GenomepatriTM Immunity – a comprehensive genetic assessment of factors which affect COVID-19 susceptibility and severity:

  • Nutritional parameters – vitamin and mineral requirements
  • Immune response
  • Drug response
  • Health risks (eg., heart disease, diabetes, blood pressure)
  • And more

Understanding your genetics helps you identify potential health risks and address them with timely interventions such as dietary intake. For example, carriers of certain MTHFR gene variants require higher dietary intake and specific supplementation of 5-MTHF, to meet their folate needs. A personalized action plan that is suited to your genetics and body, is the best bet for lifelong prevention and health.

Stay healthy, stay safe!

Disclaimer: The information provided here is not exhaustive by any means. Always consult your doctor or other qualified healthcare provider with any questions you may have regarding a medical condition, procedure, or treatment, whether it is a prescription medication, over-the-counter drug, vitamin, supplement, or herbal alternative.