How to Strengthen Your Immune System

The role of your immune system is to prevent or limit infection. Without it, every germ, bacteria, and virus would make us sick. Humans would be unable to survive.

Your immune system, when working properly, is able to distinguish between normal, healthy cells, and unhealthy ones. It can also recognize infectious microbes like viruses and bacteria. Once it recognizes a problem, your immune system launches an immune response. If it cannot do this sufficiently, you end up with an infection [1].

The immune system is very complex and requires a variety of cell types. Each type plays a different role, and each role is equally as important. In order to stay healthy, it is crucial that every part of your immune system is functioning optimally.

During a global pandemic like the one we’re in currently, keeping your immune system strong is more important than ever before. Luckily, there are several easy ways you can help improve and support it. They won’t definitely prevent you from contracting COVID-19 but can help to reduce the risk, and severity if infection occurs. As a reminder, these are by no means a substitute for mainstay precautions like social distancing, washing your hands, using sanitizer, and wearing a mask. This is all part of a cumulative approach to supporting immune defense.

How to Strengthen your Immune System

Strengthening your immune system is all about lifestyle factors. There is no magic formula to it. Your daily routines, and how well you take care of your body, will determine how strong your immune system is. The following is a list of things you can (and should) do every day to ensure your body can handle whatever is thrown at it.

Eat a Healthy Diet

Your immune system requires large amounts of vitamins and minerals in order to function properly. For this reason, your diet plays a crucial role in keeping it strong. Fruits and vegetables are of particular importance. Here is what you need to strengthen your immune system:

1.Protein

This macronutrient is vital to build and repair body tissue and fight bacterial and viral infections. Protein deficiency impairs your immune system, allowing infections to proliferate [2]. Adequate protein is important when strengthening your immune system.

The Academy of Nutrition and Dietetics recommends eating a variety of high-protein foods, such as lean meat, seafood, poultry, eggs, beans, peas, soy products, nuts, and seeds [3]. Adequare protein

2. Vitamin A

This fat-soluble vitamin protects the integrity of your skin and other tissues. It helps fight inflammation, enhances your immune system and helps to regulate your body’s immune response [4].

Foods that are high in vitamin A include sweet potatoes, carrots, broccoli, spinach, red bell peppers, apricots, eggs, or foods labeled “vitamin A fortified,” such as milk or some cereals [3].

3. Vitamin C

Vitamin Cis a potent antioxidant and supports the immune system by stimulating the production of antibodies. It promotes the oxidant-scavenging activity of the skin, which helps to protect your body against oxidative stress. Vitamin C deficiency has been shown to cause impaired immunity and high susceptibility to infections [5].

Foods that contain high amounts of vitamin C are citrus fruits such as oranges, grapefruit, and tangerines, or red bell pepper, papaya, strawberries, tomato juice, or foods fortified with vitamin C [3].

4. Vitamin E

T-cells a type of white blood cell that is an essential part of the immune system. Vitamin E is an antioxidant that works by increasing the number of T-cells that are capable of forming an effective immune response [6].

Foods that are high in vitamin E include sunflower seeds, almonds, wheat germ oil, sunflower oil, hazelnuts & its oil, salmon, rainbow trout, avocados, and peanut butter [3].

5. Zinc

Zinc has both anti-inflammatory and antioxidant properties. It helps balance the immune response, which prevents out-of-control inflammation that can be dangerous or even deadly [7].

Sources of zinc include oysters, beef, tofu, hemp seeds, and lentils.

Image Credit:MyFoodData

6. Vitamin B6

A vitamin B6 deficiency can cause your body to produce less antibodies, which are essential for fighting off infections. It also reduces the number of white blood cells, including t-cells, that your body produces [8].

Food sources of vitamin B6 are pork, poultry, peanuts, soybeans, wheatgerm, oats, bananas, milk, some fortified breakfast cereals [9].

7. Iron

Studies have shown that iron deficiency will cause you to be more susceptible to infections [10].

Foods that are high in iron include lean beef, oysters, chicken, turkey, beans and lentils, tofu, dark leafy green vegetables, whole grain bread, fortified cereals, cashews, and baked potatoes [11].

8. Vitamin D

Recently, researchers have found that there is a strong correlation between severe vitamin D deficiency and COVID-19 mortality rates. Previous studies have shown that vitamin D supplementation can help protect against acute upper respiratory tract infections [12]

Your body synthesizes vitamin D from the sun, but you can also get it from fatty fish and some fortified food products. People who live in northern climates may benefit from supplementation. Be sure to talk to your doctor before taking a vitamin D supplement [13].

Get Enough Sleep

Several important processes take place when you sleep. It is during this time that your body heals and regenerates itself. 

Your body produces and distributes important immune cells while you sleep, including cytokines, T-cells, and interleukin [12]. Without adequate sleep, your body can’t do this as effectively. This will leave you more susceptible to various viruses and diseases.

Sleep deprivation also elevates your body’s cortisol levels. Normally, cortisol is an anti-inflammatory hormone that helps your immune response. When it is chronically elevated, however, it can cause your immune system to become “resistant”. I can also lead to a greater production of inflammatory cytokines, which compromises the immune system even more [13].

Experts advise adults to get between seven and nine hours of sleep per night. Babies, young children, and teenagers need even more sleep because they are still growing [14].

Exercise Regularly

When you exercise regularly, you have a lower risk of developing chronic diseases like obesity, type 2 diabetes, and heart disease. It also makes you more resistant to viral and bacterial infections [15].

Additionally, regular exercise that elevates your heart rate and makes you short of breath is the best way to strengthen your lungs. While this won’t prevent you from contracting the coronavirus, it will decrease your risk of developing a severe form of the virus.

The CDC recommends that adults get at least 150 minutes (two and a half hours) of moderate-intensity aerobic exercise every week. This could include walking, running, or cycling. They also recommend strength training at least twice per week [16].

Try to Decrease Stress

Similarly to a lack of sleep, constant stress causes chronic elevation of the stress hormone cortisol. High cortisol levels can prevent your body from mounting an effective immune response. This makes you more susceptible to illness [17].

Try your best to manage your daily stress. Exercise is a great way to do this, as is yoga, deep breathing, and meditation. If you can, try to schedule a bit of “me time” into your day, where you do something relaxing that’s just for you. That could be taking a warm bath, reading a good book, or going for a walk in the park.

Drink in Moderation

Of course, choosing not to drink at all is always an option, but if you do enjoy alcoholic beverages, be sure to do so moderately. When you drink too much alcohol, it inhibits your immune system and slows down your recovery time.

For this reason, individuals who drink large amounts of alcohol tend to be more susceptible to pneumonia, acute respiratory distress syndrome, and some cancers [18].

Experts recommend that women drink no more than one drink per day (the equivalent to one four-ounce glass of wine), and men should drink no more than two [19].

Don’t Smoke

Anything that’s a toxin can impair your immune system, and cigarette smoke is among the worst offenders. Many of the chemicals found in cigarettes can interfere with the growth and function of your immune cells [20].

Smoking can also damage your lungs, which increases your risk for developing pneumonia, or more severe forms of viruses like the novel coronavirus [21].

Protect Yourself and Others

Strengthening your immune system is very important if you want to stay healthy, and prevent severe illness. When it comes to the COVID-19 virus, however, having a strong immune system does not replace the need for other preventative measures.

As the world continues to grapple with the COVID-19 pandemic, it is crucial that we all do everything we can to keep ourselves and others safe. This includes maintaining a safe social distance, avoiding large, crowded areas, wearing a mask when we’re in public, and staying home when we feel unwell.

It is during times like these that we all need to work together to keep each other safe and healthy.

1. https://www.niaid.nih.gov/research/immune-system-overview
2. https://journals.lww.com/ccmjournal/abstract/1990/02003/effect_of_dietary_protein_and_amino_acids_on.2.aspx
3. https://www.eatright.org/health/wellness/preventing-illness/support-your-health-with-nutrition
4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6162863/#:~:text=Vitamin%20A%20(VitA)%20is%20a,role%20in%20enhancing%20immune%20function.
5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5707683/#:~:text=It%20is%20a%20potent%20antioxidant,innate%20and%20adaptive%20immune%20system.
6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6266234/#:~:text=Vitamin%20E%20has%20been%20shown,81%2C82%2C83%5D.
7. https://www.sciencedaily.com/releases/2013/02/130207131344.htm
8. https://pubmed.ncbi.nlm.nih.gov/28367454/
9. https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-b/
10. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3173740/
11. https://www.eatright.org/health/wellness/preventing-illness/iron-deficiency
12. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3256323/
13. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4465119/#:~:text=Cortisol%20is%20ordinarily%20anti%2Dinflammatory,the%20immune%20response%20%5B18%5D.
14. https://pubmed.ncbi.nlm.nih.gov/29073412/
15. https://www.frontiersin.org/articles/10.3389/fimmu.2018.00648/full
16. https://www.cdc.gov/physicalactivity/basics/adults/index.htm
17. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4465119/
18. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4590612/
19. https://medlineplus.gov/ency/article/001963.htm
20. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5352117/
21. https://www.cdc.gov/tobacco/data_statistics/sgr/50th-anniversary/pdfs/fs_smoking_overall_health_508.pdf