Exercise and regular physical activity have a huge positive impact on your immune system. (Credit: Getty Images)
Guess how many views the hashtag "immune system" gets on TikTok? The answer: more than 100 million! Of course, not all trending content can be trusted (lemon coffee or "mucus fishing," anyone?). But, considering the COVID-19 pandemic, this certainly illustrates just how many people are looking to strengthen their immune system.
The good news is you know the best health advice already – eat fruits and vegetables, exercise and drink plenty of water. But as you age, it's natural to wonder if the basics are enough to help your immune system to do its job. As you approach your 30s or 40s, for example, is it time to start taking supplements?
Seven science-backed ways to boost your immune system
The immune system is comprised of a complex structure of organs, cells and tissues – and there is no stand-alone pill that can address the entirety of it. However, there are scientifically proven ways to boost your immunity overall. We explore seven of these below.
1. Get a good night's sleep
No over-the-counter drug can cure the common cold, but you might be more equipped to fight it off if you consistently sleep well. Chronic sleep loss makes you susceptible to infections and has also been linked to an increased risk of diabetes.
Dr Michael Chee, a professor at Duke-NUS Medical School and principal investigator of the Cognitive Neuroscience Lab, notes the rise of diabetes cases in East Asia.
"While dietary changes and reduced physical activity play a part, the contribution of poor sleep has been insufficiently acknowledged," he explains. "Experimental evidence from tightly controlled laboratory studies on sleep deprivation reveal a number of physiological changes that could, in the long run, increase the risk of diabetes."
How to start: develop a consistent sleep schedule. Stick to the same bedtime and wake-up time daily with a sleep goal of seven hours.
2. Walk, walk and walk some more
Aside from supporting a healthy immune system, walking is a great mood booster. (Credit: AIA)
Walking is one way to seriously crank up your fitness game, especially if you lead a fairly sedentary lifestyle. A study reports that people who walked at least 20 minutes a day – at least 5 days a week – had nearly half fewer sick days than those who exercised once a week or less.
According to the World Health Organization, poor physical activity is one of the leading risk factors for death from noncommunicable diseases in the Southeast Asia region. Adults between the ages of 18 and 64 can improve their health by doing 150 to 300 minutes of moderate-intensity weekly aerobic activity like walking.
Walking benefits include improved cardiovascular health, lower blood pressure, weight loss and better memory.
How to start: instead of trying for 10,000 steps, commit to doing 30 minutes of brisk walking every day.
3. Take vitamin D
The immune system needs vitamin D to fight bacteria and viruses. (Credit: Getty Images)
In some countries, many doctors prescribe vitamin D to recovering COVID-19 patients to help avoid reinfection. A 1,000 to 2,000 IU dosage given to these patients can help prevent upper respiratory infections from returning.
How to start: talk to your doctor about the right amount, as large doses of vitamin D can harm your kidneys. The general recommendation is 600 IU per day for adults between the ages of 19 and 70 years to prevent vitamin D deficiency. The recommended dosage is lower in Hong Kong (400 IU), Australia and New Zealand (200 IU) and Singapore (100 IU).
4. Get vaccinated
Vaccines are powerful immune system boosters. The pandemic highlighted their importance, particularly among the elderly. COVID-19 vaccines prevent severe illness and hospitalisation, and when inoculated, you are less likely to pass the virus to others.
How to start: by now, you should have had two doses of the COVID-19 vaccine and a booster shot. Keep track of your recommended booster schedule. Also, remember to get a flu shot annually.
5. Snack with purpose
Apples are known as a healthy snack rich in fibre, vitamins and minerals. (Credit: Getty Images)
Snacking can help control your blood sugar levels and make you less hungry. Fruit, nuts and whole-grain products are good options for healthy snacks. Make sure to read the nutrition label if you're going for pre-packaged snacks.
How to start: eat 150-calorie snacks like:
- 1 small apple
- ¼ cup of unsalted pumpkin or sunflower seeds
- 1 hard-cooked egg and 4 whole-wheat crackers
- ½ cup roasted chickpeas
6. Ease up on the worrying
The brain directly affects the stomach and intestines, and 70 per cent of the immune system is in the gut. Chronic stress can lead to gas, abdominal cramps and diarrhoea. No one can avoid stress altogether, but you can choose how to respond to it.
How to start: relax with guided body scan meditation before going to sleep.
7. Know the preventive care of your gender's immune system now
Immune function and response among men and women differ as they age. According to the Centers for Disease Control and Prevention (CDC) and based on data from Global Health 50/50, more men than women have died of COVID-19 in 41 out of 47 countries. While men are more prone to having the worst comorbidities (i.e., cardiovascular disease, high blood pressure), women are more susceptible to auto-immune diseases (i.e., Type 1 diabetes and arthritis).
How to start: get a health check-up with AIA Vitality, a wellness programme that helps members make the positive change needed to sustain healthy living. Its health assessments cover nutrition, stress, sleep and exercise. You can also enjoy discounts on gym memberships, workout gear and insurance premiums – all of which can help you lead a healthier, longer, better life.
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