How to Boost Your Immune System

As worries about the coronavirus grow, people desperately scramble for ways to protect themselves and their families.

What you need to know:

  • Greedy marketers will try to cash in on the pandemic with supplements or miracle cures. Even though there is no single supplement or super food that magically boosts immunity.
  • Rather the immune system is a complex network affected by a lifetime of exposure to germs. As well as factors like genetics, diet, exercise, stress, and sleep.
  • Therefore, it’s best to nurture the system as a whole – by giving your body what it needs to fend off illness.

In this article I’ll give you 5 proven ways to nurture your immune system. While there is no guaranteed way to prevent illness, these tips are your best bet for staying healthy.

immune system

5 Proven Steps to Nurture Your Immune System

Eat 10 Servings Of Fruit & Vegetables Daily

Surely we all know fruits and vegetables are good for us. And studies confirm that regular consumption of plant foods reduces the risk of chronic diseases1.

Most often, the advice is 5 cups of fruit and veggies per day. However, disease prevention studies suggest 9 to 13 servings of all plant-based foods. Which includes nuts, grains, and legumes.

Admittedly, 10 servings a day sounds like a lot. Particularly if you don’t like the taste and texture of veggies. But it’s not as difficult as it sounds.

What Does 10 Servings Look Like?

  • 1 salad (2 cups of leafy greens)
  • 1 medium sweet potato
  • 1 ounce almonds
  • 1 fruit smoothie (1 cup berries + 1 banana)
  • 1/4 cup of rice
  • 2 cups of broccoli

Your food choices and servings may differ depending on calorie intake and goals.

Exercise At Least 150 Minutes Per Week

Over the past two decades multiple studies proved that exercise has a significant effect on immunity3. Because working out changes your body’s response to physical stress.

However, the effects on immunity depend on the intensity, duration, and frequency of the exercise.

In other words, too much exercise actually lowers your defenses. While moderate exercise can boost immunity and decrease the likelihood of infection4.

How to Exercise Without Overdoing It

  • Workout at low to medium intensity (100 to 150 bpm)
  • Exercise for 2.5 to 6 hours per week
  • Include at least 1 or 2 rest days

Improve the Quality Of Your Sleep

When it comes to sleep, quantity is important but quality is king.

One study assessed sleep duration and “efficiency” in the weeks before a viral exposure. Where efficiency was the amount of time asleep as a percentage of total time in bed. So a higher percentage is better sleep quality.

As it turns out, the participants who slept less than 7 hours were nearly 3 times more likely to catch a cold.

Moreover, participants with less than 92% efficiency were more than 5 times as likely to catch a cold5!

How to Improve Sleep Quality

  • Go to bed around the same time every night
  • Avoid looking at screens before bed
  • Try not to eat heavy meals within 2 hours of bedtime
  • Make your bedroom as dark as possible
  • Relax your mind instead of planning the next day

Become Better At Dealing With Stress

As with exercise, a little bit of stress is a good thing. But constant worry wreaks havoc on our immune system.

To emphasize, an analysis of 27 studies concluded that psychological stress increases susceptibility to upper respiratory infection6.

Unfortunately, psychological stress is inevitable. Especially with concerns over the stock market, coronavirus, and unemployment.

So instead of trying to avoid it, we have to get better at dealing with it.

How to Deal With Stress

Supplement Your Diet Where Needed

Many scientists believe that dietary supplements do not have the same health benefits as whole foods2. However, supplements can be useful for preventing vitamin deficiency.

Specifically, vitamin D deficiency is associated with an increased risk of infection7.

In fact, our major source of vitamin D is sunlight. Which means up to 65% of people are vitamin D deficient in winter months8.

On top of that, few foods naturally contain vitamin D. With exception to oily fish like salmon, mackerel, and herring.

vitamin d levels and immune system

Adapted from Holick & Chen

Therefore, many people can benefit from increasing vitamin D intake. Some experts suggest getting at least 800–1,000 IU of vitamin D daily9.

How to Get More Vitamin D

  • Increase direct sun exposure (in moderation)
  • Eat more fatty fish
  • Supplement with D3

Personally, I take 5,000 IU of D3 daily from October to April. Since the winter sun is weak in my area and I don’t eat a lot of fish.

Although, you could get by with as little as 400 IU per day. Which can be obtained from a good multivitamin.


At the end of the day, being healthy always comes down to exercising and eating well. In additon to adequate rest, relaxation, and maybe a supplement or two.

Certainly, we also need to follow other proven health advice to protect ourselves from viral illness. Such as washing your hands, not touching your face, and social distancing.

About the Author

Jeremy Fox  –  Founder of Nutritioneering, Engineer, CPT, Bodybuilder, Coach

1) Liu, Rui Hai. “Health-promoting components of fruits and vegetables in the diet.” Advances in nutrition 4.3 (2013): 384S-392S.
2) Liu, Rui Hai. “Health benefits of fruit and vegetables are from additive and synergistic combinations of phytochemicals.” The American journal of clinical nutrition 78.3 (2003): 517S-520S.
3) Pedersen, Bente Klarlund, and Laurie Hoffman-Goetz. “Exercise and the immune system: regulation, integration, and adaptation.” Physiological reviews 80.3 (2000): 1055-1081.
4) Nieman, D. C., et al. “The effects of moderate exercise training on natural killer cells and acute upper respiratory tract infections.” International journal of sports medicine 11.06 (1990): 467-473.
5) Cohen, Sheldon, et al. “Sleep habits and susceptibility to the common cold.” Archives of internal medicine 169.1 (2009): 62-67.
6) Pedersen, Anette, Robert Zachariae, and Dana H. Bovbjerg. “Influence of psychological stress on upper respiratory infection—a meta-analysis of prospective studies.” Psychosomatic medicine 72.8 (2010): 823-832.
7) Aranow, Cynthia. “Vitamin D and the immune system.” Journal of investigative medicine 59.6 (2011): 881-886.
8) Fuleihan, Ghada El-Hajj, et al. “Hypovitaminosis D in healthy schoolchildren.” Pediatrics 107.4 (2001): e53-e53.
9) Holick, Michael F., and Tai C. Chen. “Vitamin D deficiency: a worldwide problem with health consequences.” The American journal of clinical nutrition 87.4 (2008): 1080S-1086S.

Please share with your friends... because I need your help to get the word out!