Research shows that our diet, lifestyle and stress levels all play a primary role in immune function. With that in mind, here are some practical tips for supporting a healthy immune system.
My hope is that as you read them you’ll be encouraged by how many of them you’re already doing, and of course there might be some ideas you can add in if you’d like.
As always, I want to mention that none of these statements have been evaluated by the FDA, this article is not medical advice, and it is not meant to prevent, diagnose or treat any condition. As always, please talk with your healthcare provider about any supplements or big lifestyle changes you are considering. Now that we’ve got that out of the way, let’s dive in.
1. Get Deep, Restorative Sleep
According to the Mayo Clinic:
Studies show that people who don’t get quality sleep or enough sleep are more likely to get sick after being exposed to a virus, such as a common cold virus. Lack of sleep can also affect how fast you recover if you do get sick.
During sleep, your immune system releases proteins called cytokines, some of which help promote sleep. Certain cytokines need to increase when you have an infection or inflammation, or when you’re under stress. Sleep deprivation may decrease production of these protective cytokines. In addition, infection-fighting antibodies and cells are reduced during periods when you don’t get enough sleep.”
Of course, waking up rested is sometimes easier said than done. Here are 22 science-backed sleep tips for deeper, more restful sleep.
2. Optimize Vitamin D
Vitamin D is a hormone that acts as an immune system modulator – in other words, it helps our bodies balance between an underactive immune system (increased susceptibility to infection) and an overactive one (autoimmunity). (1)
It’s no surprise, then, that low vitamin D levels are associated with more frequent infections (especially cold/flu infections) and autoimmunity. (2)
Although many people turn to oral forms of vitamin D, emerging research suggests that not all of the benefits of sunlight are necessarily related to vitamin D production.
For that reason I try to get healthy amounts of daily sunshine (without burning) as often as possible.
3. Eat Probiotic Rich Foods (Or Consider Supplements)
When someone says “immune system,” it’s easy to picture little white blood cells traveling throughout the body doing their thing. Really, though, percentage-wise about 70% of the cells that make up our immune systems live in one spot – our gut (4)
“The human gut plays a huge role in immune function,” Dr. Natalia Shulzhenko explains via Science Daily. “This is little appreciated by people who think its only role is digestion. The combined number of genes in the microbiota genome is 150 times larger than the person in which they reside. They do help us digest food, but they do a lot more than that.” (5)
Researchers believe that the bacteria that live in the gut talk to the immune cells and vice versa, and that this “crosstalk” shapes immune and metabolic function. That’s probably why in this study done with rugby players, researchers found that probiotic supplementation reduced both the number and duration of respiratory and gastrointestinal infections.
4. Stay Hydrated
According to the Cleveland Clinic:
Staying hydrated can boost your immune health too . .. Water helps your body produce lymph, which carries white blood cells and other immune system cells. Try to avoid overdoing beverages that can made you dehydrated, like coffee. Or try eating more hydrating foods, such as cucumbers, celery or watermelon.” (6)
I often make a big batch of tea with elderberry, peppermint, nettle or another herb while cooking breakfast and then pour it into a pitcher that sits on our kitchen table. When my kids walk by they usually grab a glass because they like the flavor.
5. Focus On Nourishing Foods
I’m truly grateful for medicines – both natural and otherwise – that help restore us in times of illness. However, as Karen Pendergrass put it:
Medicine is not healthcare, food is healthcare. Medicine is sick care. Let’s all get that straight for a change.”
In other words, food is one of the most powerful ways to support immune resilience and overall health. That’s why I’m making sure we get all our A, B, C’s and other nutrients, too. Here’s an overview of what I’m focusing on.
Sufficient vitamin A levels are associated with improved outcomes following infection. (7) However, the “vitamin A” found in sweet potato, carrots and other fruits and veggies is actually beta-carotene. As I wrote about in this article, beta-carotene needs to be converted into the bioavailable form of Vitamin A (retinol) that is found in animal products.
Most of us do not possess enough of the enzyme needed to efficiently make this conversion – in fact, this study found that only about 3% is converted, and about 45% of adults can’t make the conversion at all. (8) (9)
Of course, dark leafy greens, orange and yellow vegetables (sweet potatoes, carrots, squash, and peppers), cantaloupe, apricots, mangoes contain a lot of beneficial micronutrients in addition to beta-carotene. I personally just don’t rely on them alone to optimize vitamin A levels.
Important note: You will find many warnings associated with vitamin A consumption, citing its toxicity. According to Chris Kresser, LAc this warning is legitimate if you are taking Vitamin A supplements and getting it through fortified foods like cereal – yet another reason to avoid the middle aisles in the grocery store! Consuming real foods where it’s naturally occurring is not a problem as long as you’re also optimizing your Vitamin D intake. He explains why here.
The Cleveland Clinic lists vitamin B6 as one of the top three vitamins for supporting the immune system. (6) Since I prefer to give vitamins in whole-food form with possible, I take bee pollen daily which is rich in B6 as well as B1, B2, and co-factors that help with absorption. (10)
Foods rich in vitamin B6: Milk, ricotta cheese, salmon, eggs, liver, banana, avocado, and bee pollen.
According to this study, vitamin C supports “various cellular functions of both the innate and adaptive immune system.”
Our bodies don’t make vitamin C, so the only way to optimize levels is through dietary intake.
Foods rich in vitamin C: Citrus fruits, red and yellow bell peppers (and to a lesser extent green bell peppers), and homemade gummies made with vitamin C rich foods. (11)
We’ve already covered how vitamin D supports the immune system above, so I’ll just mention some good sources here:
Foods rich in vitamin D: Salmon, cod liver oil, egg yolks, and pastured lard.
According to this study, “Vitamin E, a potent lipid-soluble antioxidant, found in higher concentration in immune cells compared to other cells in blood, is one of the most effective nutrients known to modulate immune function. Vitamin E deficiency has been demonstrated to impair normal functions of the immune system in animals and humans, which can be corrected by vitamin E repletion.”
However, the Cleveland Clinics cautions that vitamin E supplementation may do more harm than good and recommend focusing on food sources instead. I recently published an article about the potential problems with common vitamin E supplements if you want to learn more.
Foods rich in vitamin E: Nuts, seeds, avocado, and dark leafy greens.
Vitamins D and K work synergistically together, so in order to get all the benefits you need both.
Foods rich in vitamin K: The two main forms are K1 and K2. Vitamin K1 is obtained through green leafy vegetables. Vitamin K2 is obtained through fermented foods and animal fats (cheese, butter and eggs) and is also synthesized by bacteria in your gut.
Other Nourishing Foods & Herbs
Bone broth – Chicken soup has long been revered for its immune supporting properties, and at least one study has concluded that it “may contain a number of substances with beneficial . . . activity” that help to ease discomfort. Here’s how to make homemade bone broth in an Instant Pot, and here’s how to make it in a slow cooker.
Garlic – According to this study, “The benefits of garlic to health have been proclaimed for centuries; however, only recently have Allium sativum and its derivatives been proposed as promising candidates for maintaining the homeostasis of the immune system.”
In other words, modern research is beginning to validate some of the traditional uses of garlic to support the immune system. Specifically, the study found that garlic supported balanced immune and inflammatory processes.
Raw, aged, or fermented garlic are considered to be more potent than cooked garlic. When consuming raw garlic, it’s best to dice it and wait ten minutes before eating so that a primary beneficial compound – allicin – has time to activate.
6. Include Nourishing Herbs & Mushrooms
Many herbs and mushrooms contain micronutrients that are thought to support health in a variety of ways. (12) I may write a more detailed article on this soon, but in the meantime here are some worth considering:
7. Reduce Stress Levels
Easier said than done, right? We all know that chronic stress impairs immune function, but for many stress is a daily reality. Here are some easy ways to reduce stress levels naturally.
8. Exercise (But Don’t Overdo It)
“Exercise causes change in antibodies and white blood cells (WBC). WBCs are the body’s immune system cells that fight disease. These antibodies or WBCs circulate more rapidly, so they could detect illnesses earlier than they might have before.” (13)
It also triggers the release of feel good hormones and slows down the production of stress hormones. Of course, exercise that is too intense can have the opposite effect and actually stress the body, so make sure not to overdo it.
9. Try Dry Brushing
Although it’s often recommended for improving skin softness and overall texture, the benefits of dry brushing are more than skin deep.
I mentioned earlier that our bodies need to be well-hydrated to produce lymph, which carries white blood cells to where they’re needed. Dry brushing is thought to help support immune function by improving lymph flow (exercise helps, too). Click here to read more about the benefits of dry brushing and how to do it.
10. Moderate Alcohol
Excessive alcohol consumption weakens the immune system, while the occasional polyphenol-rich glass of wine or beer may have a positive impact. (14)
There are lots of sources of polyphenols so if you don’t drink there’s no need to start. If you do enjoy the occasional glass that’s okay too.
Seriously. According to the Chicago Tribune, “Natural killer cells that destroy viruses and tumors increase during a state of mirth. Gamma-interferon, a disease-fighting protein, rises with laughter as do B-cells, which produce disease-destroying antibodies and T-cells, which orchestrate the immune response.” (15)
12. Try Forest Bathing
In one study, participants who forest bathed for two nights and three days experienced a 53.2% increase in natural killer (NK) cell activity. That’s important because according to Dr. Qing Li, a physician, professor at Nippon Medical School in Tokyo, and president of the Japanese Society of Forest Medicine:
One of the ways we test the health of the immune system is by looking at the activity of our natural killer (NK) cells. Natural killer cells are a type of white blood cell and are so called because they can attack and kill unwanted cells, for example, those infected with a virus, or tumor cells.” (16)
The increased NK activity the effect lasted up to thirty days. (16)
- Catch some rays
- Prioritize sleep
- Drink water
- Nourish yourself well
- Use de-stressing techniques
- Exercise, but don’t overdo it
- Consider dry brushing
- Limit alcohol
- Watch a funny movie
And as the city of Round Rock, Texas put it:
Wash your hands like you just got done slicing jalapeños for a batch of nachos and you need to take your contacts out.”
What are your tried-and-true methods for supporting immune function naturally?
Please tell me in the comments below!
1. Aranow, Cynthia (2011) Vitamin D and the Immune System
2. Centers for Disease Control (CDC) The Flu Season
3. Webb, AR et. al. (1988) Influence of season and latitude on the cutaneous synthesis of vitamin D3: exposure to winter sunlight in Boston and Edmonton will not promote vitamin D3 synthesis in human skin
4. Vighi, G et. al. (2008) Allergy and the gastrointestinal system
5. Science Daily (2013) Gut microbes closely linked to proper immune function, other health issues
6. Cleveland Clinic (2020) 3 Vitamins That Are Best for Boosting Your Immunity
7. World Health Organization (WHO) Micronutrient Deficiencies
8. Kresser, Chris. Why you can’t get vitamin A from eating vegetables
9. Hickenbottom, Sabrina et. al. (2002) Variability in conversion of β-carotene to vitamin A in men as measured by using a double-tracer study design
10. Komosinska-Vassev, Katarzyna et. al. (2015) Bee Pollen: Chemical Composition and Therapeutic Application
11. Jones, E and Hughes, R.E. (1984) The influence of bioflavonoids on the absorption of vitamin C
12. Healing Mushrooms by Tero Isokauppila
13. U.S. National Library of Medicine. Exercise and immunity
14. Romeo, J et. al. (2007) Moderate alcohol consumption and the immune system: a review
15. Ricks, Delthea (1996) Doctors: Laughing Is Nothing To Joke About
16. Li, Qing (2018) Forest Bathing: How Trees Can Help You Find Health and Happiness