Since the pandemic was declared, so many of us have become amateur immunologists. That’s probably why questions about how to boost immunity are being fired into Google search faster than ever.

To help with answers, we’ve consulted medical and university websites for reliable information about how to strengthen your immune system. Most of the information here applies to everyone; some is specific to people who are 65+.

The answer is ‘sometimes’. One of the pandemic’s biggest mysteries has been why some people recover quickly from Covid-19 and others become severely sick or die. After many months of study, it’s now known that the natural immune response in some people can go haywire. When this happens, the immune system causes inappropriate inflammation and fluid build-up that can block airways and cause organs to fail.[1]

While older people and those with underlying medical conditions are more likely to get very sick from Covid-19, severe illness can happen at any age.[2] Being young and fit is no guarantee of a mild case. That’s why Covid-19 vaccination is recommended for nearly all age groups in New Zealand.

Studies have shown that about 95% of people who received both doses of the Pfizer vaccine were protected against getting seriously ill.[3] However, you’ll still be susceptible to all the usual cold and ‘flu viruses going around. That’s why your doctor will continue to remind you to get an annual ‘flu jab.

Aside from getting recommended vaccines, you can help yourself by keeping your immune system in good shape. Here are some tips to help with that:

Eat immune boosting foods

If you’re not getting adequate nutrition, your immune system is going to suffer. Many adults over the age of 65 are at nutrition risk, which can compromise their immune response.

As well as ensuring you’re getting adequate nourishment, a wide variety of whole, minimally processed foods will help your immune system to stay strong. Both malnutrition and ‘micronutrient malnutrition’ (which can occur when older people have less variety in their diets)[4] need to be avoided for an effective immune system.

The general recommendation is to focus on fruits, vegetables, nuts, seeds, legumes and wholegrains, as well as smaller amounts of high-quality meats and dairy products. Avoid refined and highly processed foods.[4]

For a strong immune system, prioritise these nutrients:[5]

• Vitamin A from eggs, cheese, kumara, pumpkin, carrots, spinach, broccoli, rock melon and dried apricots.
• Vitamin C from citrus fruits, kiwifruit, pineapple, leafy green veges and capsicum.
• Vitamin D from eggs, salmon, fortified dairy products and 10 minutes of sun exposure on bare skin each day.
• Vitamin E from almonds, peanuts, sunflower seeds and avocado.
• Zinc from shellfish, red meat, chickpeas, eggs, dairy products and cashew nuts.
• Folate from leafy greens, legumes and avocado.
• Iron from red meat, poultry, oily fish, beans, broccoli and kale.
• Selenium from eggs, seafood, meat, poultry and Brazil nuts.

The foods mentioned here are just a few easy-to-find examples. For each nutrient, there are many other sources.

Get daily exercise

Do something every day that gets your heart pumping and your muscles working. Movement promotes good circulation, which helps your immune system to operate more effectively.[6]

Here are some exercise ideas:

• Go for a brisk walk around your neighbourhood, being careful to stay two metres away from other people.
• Try the walking version of interval training: walk as fast as you can for 20 seconds, then slowly for 10 seconds, repeat until you get home.
• Find a gym that specialises in fitness classes for over 60s.
• Hire a personal trainer to help you and a couple of friends get fit; you can share the cost.
• Find a yoga class or senior workout on You Tube – there are heaps of them. See if you can stream You Tube through your TV, to see a bigger screen.
• Download an exercise app for your phone, like Daily Workouts or 30 Day Fitness at Home.
• Put on your favourite music and dance around the living room.
• Vacuum the house, sweep leaves, pull weeds or mow the lawn.
• If you have a stationary bike or treadmill, dust it off and use it. Listen to audio books to prevent boredom.

Focus on gut health

Around 70% of your immune system is located in the gut, so if gut health is compromised it can negatively affect your immune function.[7]

Try these eating tips to include more prebiotics and fibre and improve gut health:

• Kiwifruit, garlic, leeks and onions are particular good prebiotics, so try including these foods in your daily diet.
• Snack on raw fruits, nuts, or seeds.
• Include two to three vegetables (and their skin!) in each meal.
• Swap meat for legumes or beans occasionally.
• Try oats for breakfast and opt for wholegrain/brown bread, brown rice and wholewheat pasta when possible.
• Consume probiotic foods, like natural yoghurt. Other probiotic foods that are commonly available today are kombucha (a fermented drink), sauerkraut (fermented cabbage) and miso (fermented soya bean paste).

Sleep for immune health

A lack of sleep can impair your immune system, because your body carries out cellular repair processes when you’re asleep.[8]

For better sleep, avoid coffee and tea after midday. Find a herbal or fruit tea you like, as an alternative. Also, avoid watching TV or looking at your phone right before bed. Instead, read or listen to a book until you feel sleepy. To calm your mind when the lights go out, try ‘square breathing’ – breathe in for three counts, hold for three counts, out for three counts, hold for three counts, repeat until you fall asleep.

Another go-to-sleep trick is cognitive shuffling. It’s a simple brain game that uses random words and images. This randomness causes the processing part of your brain to lose interest and relax. Start the game by thinking of a five letter word. Then visualise as many new words as you can, beginning with the first letter of your starting word. Once you’ve exhausted the first letter, move on to the second. Repeat until you’ve spelled out your starting word or are fast asleep.

Give your immune system enough water

Are you in the habit of hydrating mostly with tea and coffee? Now is a good time to re-programme yourself to drink more plain water. Water is important for delivering nutrients around the body. It also aids digestion, and keeps your nose and throat moist. This last point is very important, because mucous is one of the immune system’s first defence barriers. To ensure you’re drinking enough water every day, fill a jug or water bottle with 1.5 litres in the morning. See if you can get through all of it before bed (in addition to tea and coffee).

Read another article related to good health – What does a healthy meal look like?

[1] https://www.immunology.org/news/coronavirus-immunology-qa-what-you-need-know-about-our-new-report

[2] https://www.cdc.gov/aging/covid19/covid19-older-adults.html

[3] https://www.health.govt.nz/our-work/diseases-and-conditions/covid-19-novel-coronavirus/covid-19-vaccines/covid-19-vaccine-effectiveness-and-protection#:~:text=The%20clinical%20trials%20performed%20on,effective%20after%20only%20one%20dose.

[4] https://www.health.harvard.edu/staying-healthy/how-to-boost-your-immune-system

[5] https://health.clevelandclinic.org/eat-these-foods-to-boost-your-immune-system/

[6] https://www.mayoclinic.org/healthy-lifestyle/fitness/in-depth/aerobic-exercise/art-20045541

[7] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2515351/

[8] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3256323/