The 2019 novel coronavirus, also known as COVID-19, has taken the world by surprise with its highly infectious nature and mortality rate. Relatively unknown until the outbreak, the virus has expanded to almost every part of the world.
What’s most concerning is that while we know that COVID-19 is part of a large family of viruses that include Middle East Respiratory Syndrome (MERS-CoV) and Severe Acute Respiratory Syndrome (SARS-CoV), there are many traits of this virus that we have yet to uncover, such as the dynamics of transmission. According to the World Health Organization (WHO), it could take up to 18 months for the first COVID-19 vaccines to be made publicly available.
Only an approved drug can treat or cure, or prevent the transmission of, COVID-19 and other diseases. In the absence of any vaccine to date, we are left with practical prevention measures, such as maintaining proper hygiene, wearing a mask when necessary, or maintaining social distancing. It may also be useful to keep our bodies strong so that our immune systems function well.
After all, our immune system is one of the most effective forms of defence against viral infections. There are two categories of immune functions in everyone’s body – the innate immunity which prevents diseases from entering the body and adaptive immunity which eliminates or prevent the growth of pathogens, such as viruses and bacteria, in our body.
However, increasing the body’s immunity is not as straightforward as it sounds. There remains much about the immune system that researchers are still working to understand, but what we do know is the tangible connection between the immune system and nutrition.
How nutrition impacts the body’s immune system
To understand how nutrition and diet affect an individual’s immune system, we need to delve deeper into the role of epigenetics – the study of biological mechanisms that switch our genes on and off.
While the idea of epigenetics might seem complex, consider the example of honeybees. Despite having the same DNA sequence, honeybees produce three different organisms – workers, drones and queens – and this is dependent on the diet that the larvae are fed. This demonstrates that while all worker bees are born with the genetic ability to become queens, the workers’ diet ultimately affects how their genes are expressed and manifest physically.
In the same vein, while all humans are 99.9% genetically identical, epigenetics makes us unique by the different combinations of genes that turn on and off – which explains why some of us have red hair and others black, or why some of us have darker or lighter skin, for instance.
What we eat, where we live, how much we sleep, how we exercise, and even who we live with, all causes chemical reactions that can alter our health status. Added to the mix is our microbiome, which are the microorganisms we depend on to protect us against germs, break down food for energy, produce vital vitamins and bolster our immune system.
The largest part of the immune system – approximately 70% of it – is located near the intestines, which monitors the intake of food and how the body uses it. This makes it critical for us to consume a balanced diet with the right vitamins, minerals and nutrients while maintaining a healthy lifestyle. This requires more than just changing the intake of one or two nutrients but involves balancing the entire diet to ensure that there is optimal nutrition intake at a cellular level.
Four essential groups of nutrients to help individuals strengthen their immune system
Also known as the basic building blocks of the body, protein allows the body to manufacture antibodies that it requires to defend against invading viruses and bacteria. To ensure that we have sufficient levels of protein in our diet, we can eat more healthy protein foods such as fish, poultry, lean meats, soy foods and low-fat dairy products.
Vitamins and phytonutrients
Vitamins A and C, as well as phytonutrients, are key players in immune system health. As one of the biggest immune system boosters, Vitamin C encourages our body to produce antibodies that fight diseases. It is essential to maintain a daily intake of vitamin C as the body does not produce or store it. Vitamin A supports the health of our skin, tissues of our digestive tract and respiratory system.
Phytonutrients, which are found in vegetables and fruits, reduce our body’s oxidative stress, which may weaken its ability to fight off illnesses. A number of phytonutrients have been shown to reduce the risk of cancer and cardiovascular diseases, fight inflammation, lowering blood pressure, and boost the overall health of our immunity system.
Probiotics and prebiotics
The digestive system plays a central role in supporting immune function. The intestinal tract is the main route of contact with the external environment and is a pathway that contains microbiomes that aids digestion as well as the absorption of nutrients. Having the right gut bacteria has been associated with benefits such as weight loss, improved digestion, healthier skin, and most importantly enhanced immune function, although research in these areas is not conclusive or universally applicable.
Studies have shown that probiotics, which are ‘good bacteria’, are useful in maintaining the digestive system, and prebiotics, types of fibre that the human body cannot digest, serve as food for these probiotics.
Omega-3 fatty acids
Omega-3 fatty acids, such as DHA and EPA, are healthy and essential types of fat which can be found in food such as chia seed and supplements such as fish oil. Omega-3 fatty acids may enhance the functions of immune cells, which plays a large role in both the innate and adaptive system that responds to infections.
Nutrition is no substitute for an effective drug and at the same time, drugs or health supplements are no substitute for good nutrition. Good nutrition certainly won’t prevent you from contracting COVID-19 or other diseases. Maintaining a strong immune system, though, is something everybody should do.
With inputs from Dr. David Heber, M.D., PhD, FACP, FASN – Chairman, Herbalife Nutrition Institute talks about the importance of nutrition in boosting the body's immunity