How to Boost Your Immune System During the Coronavirus Outbreak

Reviewed by Kimberly Langdon
Featured image for article on how to boost your immune system during the coronavirus outbreak

By now, the whole world knows what the coronavirus disease 2019 (COVID-19) is. After all, the global pandemic has been going on for almost a year now. The World Health Organization proclaimed the outbreak as a pandemic on March 11th, 2020. And while there are vaccines now, it will take some time before we bid adieu to this virus. In this post, we are going to discuss how to boost your immune system during this ongoing pandemic.

The virus is transmitted through a variety of means – from person-to-person and via contact with contaminated surfaces. Infected individuals expel saliva and respiratory secretions or droplets when they talk, cough, sneeze or sing. This is why the wearing of face masks and personal protective equipment is highly encouraged when going out to public places.

Who is at higher risk of getting sick with COVID-19?

COVID-19 is a highly contagious disease. It affects people differently. Many don’t experience any symptoms at all. Others only have a mild case. And many others get sick very badly but ultimately survive. Unfortunately, for about 2-3% of people infected, it’s the end of the journey for them. So, who’s at increased risk of getting the end of the short stick, that is, the severe version of COVID-19?

  • Older adults
  • Pregnant women
  • People with serious chronic conditions, such as diabetes, chronic kidney disease, various heart conditions, lung disease, obesity, and cancer
  • Anyone with an immunocompromised state
  • Smokers

If you or anyone you know belong to the at-risk category, please do take some precautions to reduce your chances of contracting this disease. It’s scary, we know, but it’s important NOT to panic to keep on protecting yourself and others.

know how to boost your immune system

So, how to boost your immune system?

Everyone is talking about boosting the immune system to fight coronavirus, but what are the steps you need to take to keep your immune system strong and healthy? Here are our top 5 health tips:

1. Reduce your stress levels

Stress has a direct effect on immunity. When you experience a stressful event, your body responds by releasing hormones like cortisol and adrenaline, which affect your production of T-cell lymphocytes (1), a type of immune cell responsible for fighting infections. Your immune system will overcome short-term stress. But when stress becomes chronic, you can become susceptible to viruses (including coronavirus) and bacterial infections.

Here are a few ways you can reduce your stress and boost your immune system at the same time:

  • Introduce more time to relax
  • Exercise regularly
  • Get more quality sleep at night
  • Express your creative side
  • Work on your favorite hobbies, i.e. reading, gardening, painting, baking, etc.
  • Even music strengthens immunity (2)

2. Exercise regularly (at home)

With all the stay-at-home orders going on in many places, exercising in the gym and in public spaces may not always be possible. Fortunately, you can still workout at home. But it’s important to not overexert yourself!

Moderate exercise can indeed boost your immunity but overdo it and you’ll end up stressed. That said, moderate exercise can potentially reduce the severity of an upper respiratory tract infection, which is good because COVID-19 symptoms often present in this part of the body (3).

So, what exactly counts as moderate exercise?

Well, it’s any physical activity that raises your heartbeat by about 50-70% of your max heart rate. Do this for a cumulative 150 minutes a week (you can do 30 minutes x 5 days).

Here are some exercises you can do at home: 

  • Jogging in place
  • Jumping rope
  • Jumping jacks
  • Kickboxing
  • Dancing
  • Staircase exercise
  • Gardening
  • Some housework, such as vacuuming
  • Walking or jogging on a treadmill
quit smoking asap to boost immunity

3. Quit smoking

I know it’s easier said than done, especially if you’ve been smoking for years! But it’s no fake news that smoking increases your risk of developing a respiratory tract infection. The coronavirus attacks the lungs, so if they’re pre-damaged courtesy of your smoking habit, then you’re likely to experience complications (4). Stop smoking well before the virus gets you (hopefully not but better safe than sorry). It’s a huge step you need to take for your health.

4. Get enough sleep

Who said sleep is overrated?! Well, it’s not. The truth is sleep plays a big role in boosting and regulating your immune system. Remarkably, recent studies show how the immune system replenishes itself during sleep. Even one night without sleep affects the innate immune system. This is the body’s first line of defense against viral infection. A strong immune system responds immediately to prevent the spread of the virus throughout the body (5).

“Natural killer” cells are a type of lymphocyte (a white blood cell) available in blood circulation. These cells play a crucial role in this first line of defense against viruses, as they immediately recognize virally infected cells and rapidly eliminate them. So, while you’re working to boost your immune system during the coronavirus pandemic, it’s crucial to get enough sleep.

Lack of sleep reduces white blood cells

Researchers found that sleep disturbance causes a reduction of natural killer cell activity. This means that if you don’t get enough sleep, you’re not getting that natural killer cell protective activity. This leaves you prone to catching viruses such as colds and the flu, even coronavirus.

So, is it really possible to boost your immune system by catching up on your sleep? Let’s look at the study that explains this in detail.

get enough quality sleep

A study on sleep and natural killer cell activity

A group of researchers conducted several studies to test whether sleep loss alters daytime values of cellular immune function and the effect of night partial sleep deprivation on natural killer cell activity (6, 7). Here are the findings:

  • One study included 23 medically and psychiatrically healthy male volunteers. After a night of sleep deprivation between 3 and 7am, natural killer cell activity was reduced in 18 of the 23 subjects with average virus destruction activity reduced significantly.
  • Another study included 42 medically and psychiatrically healthy male volunteers. After a night of sleep deprivation between 10pm and 3am., a reduction of natural immune responses measured by natural killer cell activity was found.
  • In both studies, after a night of recovery sleep, natural killer cell activity had returned to baseline levels.

These studies results indicate the role of early night sleep in the modulation of natural immunity and demonstrated that even modest sleep disturbances produce a reduction of natural killer cell activity.

Therefore, getting a good night’s sleep helps boost your natural killer cell activity to get rid of viruses and keep you healthy. Sleep deprivation, on the other hand, will reduce your immune response.

The link between sleep and respiratory infections

Interestingly, there’s also a link between upper respiratory tract infections and poor sleep. Prather et al.’s study on more than 22,000 Americans showed that people who slept 5 hours or less, or reported low-quality sleep, were more likely to experience a chest infection or head cold than those who slept for 6 or 9 hours (8).

If you are experiencing sleeplessness due to coronavirus anxiety, try to relax before going to sleep at night to avoid waking up in the middle of the night feeling anxious.

Here are some tips to help you sleep better:

  • Do something relaxing like reading or listening to relaxing music until you feel drowsy.
  • Keep your bedroom comfortable; temperature, lighting, and noise should be controlled to help you to fall (and stay) asleep.
  • Make sure your bed is comfortable.
  • Keep away all electronic devices and mobile phones so you can ensure a quiet place, free of distractions.
  • Pay attention to what you eat and drink, avoid heavy or large meals within a couple of hours of bedtime.
  • Don’t consume caffeine late in the day.
  • Reduce irregular or long daytime naps.
  • Take a good Magnesium supplement.
  • Drink a soothing beverage like chamomile tea, which has been shown to promote sleep and relaxation.
  • Maintain a regular sleep-wake schedule.
improve your diet

5. Improve your diet

There are several studies suggesting that nutritional deficiencies can weaken your immune system and make you more vulnerable to infections. Increasing the intake of important micronutrients leads to a better immune response (9).

So, what does this mean exactly? Well, eating a healthy diet is necessary for good health and a robust immune system. However, many people still fall short of some needed nutrients, including many older adults who aren’t getting enough nutrients from their diets. Fortunately, these nutritional imbalances can be “plugged” through the use of appropriate dietary supplements.

Eating enough fruits and vegetables

If you’re a fan of fruits and veggies, here’s some good news. These foods increase the production of T-cells and lower the level of c-reactive protein (an inflammation marker) (10). This is important because in severe cases of COVID-19, the inflammatory response is extreme, and the body attacks both the virus and healthy tissue! Keeping inflammation levels low is therefore beneficial and may offer some level of protection against the virus.

Avoid processed foods

Processed foods are delicious, but far from healthy. Avoid or limit the following:

  • Fried foods
  • Sweet and sugary treats
  • Excessive carbohydrates especially refined carbs
  • Preserved or cured meats
change your diet if you want a healthy immune system

How to boost your immune system by changing your diet

Here’s a table summarizing the top 15 foods you can eat to boost your immune system. Scroll down if you’d like to read the full details about each food!

FoodWhy eat it?
AlmondsVitamin E, fiber, protein, good fats, dietary minerals
BlueberriesRich in antioxidants
BroccoliVitamins A, C, E and K, folate, fiber, protein, dietary minerals
Dark ChocolateRich in bioflavonoids, resveratrol, PQQ (all antioxidants)
CurcuminAnti-inflammatory and antioxidant effects
Fatty fishOmega-3 fatty acids, such as DHA and EPA
GarlicAntiviral that can help ward off the common cold
GingerWorks as an antioxidant
Green teaAbundant in antioxidants!
KefirExcellent source of natural probiotics
Citrus fruitsVitamin C
Bell pepperVitamin C and flavonoids
SpinachVitamins A, C, and K, dietary minerals, carotenoids, flavonoids
Sunflower seedsVitamin E, vitamin B complex, dietary minerals
Sweet potatoesBeta carotene


Almonds are an excellent source of vitamin E, an antioxidant that helps fight free radicals and helps your immune system function. These tree nuts are also rich in fiber, protein, monounsaturated fats (good fats), manganese, and magnesium (11).


These sweet, little fruits are rich in anthocyanins, a type of flavonoid with antioxidant properties. A 2016 systematic review found that people who ate flavonoid-rich food like blueberries were less likely to get sick from the common cold and upper respiratory tract infection (12).


Eat these green cruciferous veggies cooked or raw and you’ll get a healthy dose of antioxidants, vitamins and minerals! It’s a rich source of vitamins A, C, E and K, folate, fiber, protein, iron, calcium, potassium, and magnesium. Eating this regularly – and its close cousin cauliflower – can help boost your immune system health.

Just a word of caution when cooking though – a study found that cooking in water for too long can cause antioxidants to leach. Microwaving, on the other hand, retains and even enhances the antioxidant content of broccoli (13).

Chocolate (dark)

Surprised? Yes, dark chocolate which contains at least 70% cocoa powder is healthy. It’s an excellent source of antioxidants such as bioflavonoids, resveratrol, and PQQ. It’s also rich in fiber, iron, magnesium, manganese, copper, selenium, zinc, phosphorus, calcium, and potassium. Dark chocolate helps reduce bad cholesterol, reduce the risk of heart disease, improve brain function, and helps you feel good!

Read more about why chocolate is considered a superfood here.

Curcumin (or turmeric)

Turmeric is a spice commonly used in Asian food. Consuming turmeric may improve immune response, due to its curcumin content as this compound has antioxidant and anti-inflammatory effects.  

Check out our Intelligent Labs Meriva Curcumin Complex supplement. Meriva curcumin has been shown in studies to decrease inflammation levels by up to 1600%, as measured by the reduction in c-reactive protein levels (14).

eat fish rich in omega-3

Fish rich in Omega-3

Fish isn’t just a rich source of protein, it’s also an excellent source of Omega-3, an essential fatty acid that the body needs to function properly. Fatty fish like tuna and salmon are good sources of Omega-3.

Research shows that omega-3 fatty acids enhance the function of immune cells, which helps protect your body from viral infections (15). Moreover, it’s also a powerful anti-inflammatory with neuroprotective properties. In fact, it has a long list of health benefits as you can read in this article.


Eating lots of garlic may give you a bit of bad breath, but it’s long been known for its health benefits. It’s an effective antiviral, especially if chewed raw. This is why in some cultures, garlic is often used to treat colds and other illnesses. In one study, researchers found that people who took garlic supplements containing allicin caught fewer colds than those who didn’t (16).


Similar to garlic, ginger has also been used for centuries to treat various conditions, such as the common cold, chills, digestive issues, and even fever. This is because ginger has antioxidant properties and contains nutrients like iron, zinc, calcium, folate, phosphorus, and magnesium. Try drinking ginger ale to warm your belly and boost your immune system at the same time!

Green tea

Green tea does have a bit of caffeine, but not as much as coffee or black tea. Just like blueberries, green tea is rich in flavonoids. According to a study, these catechins have antiviral properties. They block the enzymes that allow the virus to reproduce, thus stopping the virus in its tracks (12).


Just like its thicker cousin (yogurt), kefir is also rich in probiotics or live cultures of beneficial bacteria which is great for your gut health. But kefir is usually fermented longer than yogurt, which gives the bacteria more time to grow.

According to a 2017 study, kefir can help boost the immune system. Regular consumption helps reduce inflammation, fight off bacteria, and even increase antioxidant activity (17).

citrus fruits are rich in vitamin c

Citrus fruits

Citrus fruits like orange and grapefruit are rich in Vitamin C. Many people take Vitamin C when they feel a cold coming down. This is supported by a study which reported that taking Vitamin C may help prevent viral infections, such as the common cold (18). And if you do get the cold, then eating Vitamin C-rich food may help reduce the duration of symptoms.

Bell pepper

Ever tried stuffed bell pepper? You should! They not only taste great, but they’re also a fantastic source of Vitamin C. A 100g of red bell pepper contains 212% DV of Vitamin C and 62% DV of Vitamin A. But yellow pepper takes the cake when it comes to Vitamin C – a 100g serving contains a whopping 305% DV!

Additionally, red bell pepper is rich in quercetin, a flavonoid that has been shown to inhibit flu infection. Quercetin also helps reduce inflammation, blood pressure, and allergy symptoms (19).  


Popeye loved his spinach, didn’t he? And why not? This green, leafy veg is a nutritional powerhouse with high levels of vitamins A, C, and K, and many essential minerals. It also contains carotenoids and flavonoids. All these nutrients work together to help boost your immune system and fight off infection (20).

Sunflower seeds

Roasted sunflower seeds make for the best snacks. Sprinkle them over a salad or eat them by the mouthful. These tiny nuts pack a punch full of vitamin E, copper, vitamin B1/B3/B6/B9, selenium, phosphorus, manganese, and magnesium.

Sweet potatoes

Sweet potatoes are a rich source of beta carotene, an antioxidant that’s also a precursor to Vitamin A. As an anti-inflammatory vitamin, it plays a key role in promoting the body’s immune response (21).

boost your immune system by taking vitamins

How to boost your immune system by taking vitamins and minerals

Here’s a list of vitamins and minerals that can help improve your immunity:

Vitamin D

Vitamin D is an important vitamin as it contributes to the normal function of the immune system. A 2012 study has shown that supplementing with Vitamin D may help prevent respiratory tract infections (22). Aim to keep your vitamin D in the normal range (between 50 and 175 nmol/L) – vitamin D levels can easily fall, especially in the winter months. You can test your vitamin D with a Vitamin D Blood Test or as part of a general health check.

Fortunately, Vitamin D can be had in a variety of ways – food, sun, and supplements. Foods rich in vitamin D include oily fish, red meat, liver, and eggs. As for the sun, sunbathe for about 10-20 minutes at noon time (between 11am and 2pm). You see, when sunlight hits the skin, your body makes Vitamin D.

Just a word of caution though: if you’re sensitive to sunlight and burn easily, take a Vitamin D supplement instead (check out SHIELD Immunity Booster).

Vitamin C

There is some evidence that Vitamin C can prevent and shorten the duration of a respiratory tract infection (23, 24). Vitamin C is a potent antioxidant that protects your cells from free radical damage. This water-soluble vitamin also helps maintain the normal function of the immune system. The catch with Vitamin C is that the body does not produce or store it, so you need to get it daily. The recommended daily intake is at 90mg, but the safe upper limit is 2,000mg. Fortunately, many different fruits and veggies are excellent sources of Vitamin C.

Live cultures

Majority of your immune system resides in your gut. It’s therefore essential to keep your gut microbiome healthy to keep your immunity in tip-top shape. One of the best ways to do this is by taking live cultures of beneficial bacteria. These ‘good’ bacteria keep the ‘bad’ ones in check. A 2015 study showed that people (both adults and children) who took live cultures were better protected against upper respiratory tract infections than the placebo group (27).

Live cultures are available in fermented/cultured food like yogurt, kefir, kimchi, miso, and sauerkraut. If this doesn’t appeal, check out our live cultures with fibre supplements, available for adults, women, and kids.

intelligent labs live cultures with fibre for adults, women, and children

Vitamin B6

Just like Vitamin C, Pyridoxine or Vitamin B6 is another water-soluble vitamin that our bodies can’t produce. So, we need to either get it from food or supplements. It’s vital to our immune system’s normal functioning as well as a host of other important biological functions. B6-rich foods include salmon, tuna, chicken, chickpeas, and green veggies.

Vitamin E

Vitamin E is a well-known antioxidant that’s found in higher concentration in immune cells. It’s so important that a deficiency leads to impaired immune system function. Fortunately, a consistent intake of vitamin E can correct the deficiency. Add more almonds and sunflower seeds to your diet to get your daily intake of Vitamin E.


Selenium is a trace mineral that’s also a powerful antioxidant and immunity booster. Unfortunately, selenium levels in the soil are slowly becoming depleted due to modern agricultural methods, which means the food we eat gets less of this important nutrient. Selenium deficiency increases the likelihood of you contracting a viral infection (25).


Zinc is another immunity booster that also has antioxidant and anti-inflammatory properties. While it may not solely stop you from getting infected with coronavirus, it may help speed up the recovery. A 2012 meta-analysis found that people who supplemented with Zinc recovered faster from the common cold than people who didn’t (26).

woman spraying hand sanitizer

Stay safe

Here are 8 tips to keep yourself and your family safe during the pandemic:

  • Wear a face mask, e.g. surgical mask, N95 mask, fabric/cloth mask, when going out. This helps trap droplets and reduce virus transmission.
  • Keeping your hands clean is super important, so wash them often with soap and water (aim for at least 20 seconds per wash).
  • Always bring isopropyl alcohol or a hand sanitizer (at least 60% alcohol) wherever you go, so you can clean up right after touching unsanitary surfaces.
  • Avoid close contact with sick people.
  • Avoid touching your mouth, nose, and eyes with unwashed hands.
  • Disinfect frequently touched surfaces, e.g. door handles, light switches, phones, countertops, etc.
  • Always be on high alert in public and as much as possible put some distance (at least 6 feet) between yourself and other people.
  • Consider wearing gloves when out in public but remember to practice common sense. Don’t rub your gloved hands on your face as that will defeat the purpose of wearing gloves!


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