The first step beat the Coronavirus is to develop a strong immune system.

We’re staying safe at home, washing our hands and keeping a physical distance from others. Sure, you may pop a vitamin C tablet here or there, or even getting a workout in at home, but are you looking into the myriad ways we can boost our immunity against illness during this crucial time?

A balanced diet and lifestyle are of course key, quarantine or not. But if you’re looking for a quick fix, you’ll want to look into supplementation and nutrition to really help fill in the gaps of what you’re missing — and really kick your body’s natural defences into high gear. As well if you’ve been working from home, or if you’ve been keeping your regular grocery runs limited, keeping a stash of supplements on hand may also prove to be useful to optimise your nutrition.

We reached out to Miles Price, LifeHub’s Functional Medicine and Clinical Nutritionist, to explain a little further with some scientific evidence, with five ways to boost our immune system.

1. Get some sun for a vitamin D boost

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Price says, “Vitamin D3 is good at preventing respiratory tract infections, bacterial or viral. It’s essential for the regeneration of the epithelial barrier — made up of mucosal immune cells that line our lungs and throat. Vitamin D3 also promotes the health and maturation of immune cells including neutrophils, lymphocytes, and dendritic cells.” Respectively, these cells ingest and destroy invaders, help create antibodies in response to invaders, and recognise pathogens and raise the alarm to activate other immune cells.

“Aim for at least 2,000IU/day or better still, get a health test at a clinic and bring up your levels to 50ng/dL. Studies have shown that optimal blood levels of vitamin D3 are around 50ng/dL, while if you have less than 30ng/dL, you’re considered clinically deficient in D3.”

2. Get enough retinol and vitamin A

boost immune system - eggs
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“Vitamin A’s key role is also in the mucosal barrier which lines the lungs and throat, and it’s required for the proper functioning of this barrier to provide the first line of defence. The adaptive immune system response requires the production of certain antibodies, and vitamin A potentiates the antibody response, ensuring a more effective immune activation.

The onset of any viral or bacterial infection actually reduces retinol levels very rapidly, therefore being protected prior to infections with sufficient levels has been shown to reduce the severity and incidence of infectious disease.

Look into getting at least 5,000IU of vitamin A per day. Great sources are cod liver oil, eggs and cheese. For reference, one large egg gives about 500IU each, 100g of cheddar cheese gives 1,000IU, while one teaspoon of cod liver oil provides 4,500IU. If you have one 100g serving of lamb’s liver, that’s already 24,000IU — one serving and you won’t need any more that week!”

3. Boost your zinc levels

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If you’re deficient in zinc, you may be more susceptible to viral infections.
Price says, “specifically, zinc has been shown to reduce the incidence of lower respiratory infections, such as pneumonia, which just so happens to be one the complications of CoViD-19. Zinc can help to reduce the inflammatory response from an infection, therefore reducing those lingering symptoms.
Zinc’s role in the innate immune response — the body’s first response when someone becomes infected in the first few hours — is vital. It stimulates the activation of NK (natural killer) cells and macrophages which target the invader.

With the SARS coronavirus, zinc has been proven to target three different areas of the virus biology and interfere with the virus replication process. Therefore, we can assume that the same will apply for the CoViD-19 virus.”

You’ll want to try and optimise your zinc levels to 30mg a day. The best sources for zinc are found in red meat (100g serving provides 4.5mg); chickpeas (1 cup provides 4.1mg); cashews (a 28g serving gives 1.6mg) ; and oysters (six medium oysters give a whopping 32mg).

4. Load up on pre- and probiotics to improve your gut immunity

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Improving your gut bacteria by adding pre- and probiotic strains such as lactobacillus and bifidobacterium can also help your body react faster to infection.

Price explains, “oral probiotic bacteria interact with the intestinal epithelial cells (IECs) or immune cells in the lining of the gut, and induce the production of different immune messengers, or cytokines. These activate the innate immune response in the body. In another study, oral probiotics stimulated the production of antibodies in the body when an infection was present. The gut bacteria interact with the immune system of the body to make a more vigilant response.”

5. Take plant-based vitamin C, and split your dosage throughout the day

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We all recognise the importance of vitamin C when it comes to beating colds and flu, largely due to its antioxidant power. Studies have shown that vitamin C supplementation may lower the risk of pneumonia, and can aid the body with antiviral activity.

Price adds, “for immunity, vitamin C has been shown to stimulate both the production and function of neutrophils and lymphocytes — which recognise foreign pathogens and bind to them.

Also, white blood cells (WBC) take up large amounts of vitamin C which help protect them against oxidative damage. This oxidative damage happens when WBCs produce oxidative compounds to help degrade or kill invading microorganisms, so the vitamin C acts as a form of self-protection for the cell.

Acerola is a food source of Vitamin C, and when coming from a plant source, it comes with vitamin C co-factors like flavonoids, which enhance the antioxidant effect of vitamin C.

When taking vitamin C there is a rate-limiting absorption limit in the gut at around 800mg at one time, so it’s best to split the dosage at say 500mg in morning and evening.”

This article first appeared on Lifestyle Asia Hong Kong.

Evelyn Lok
Managing Editor
When not trying out the latest beauty and wellness trends, Evelyn is likely enjoying a perfectly balanced negroni or exploring some of Hong Kong's best new places to eat and drink. At Lifestyle Asia she covers everything from the biggest events in town to interviews with Hong Kong specialists, with topics spanning art, food and drink, health, tech, and travel.