9 Activities You Didn’t Know Can Boost Your Immune System

Image courtesy of Kelly Sikkema via Unsplash.

With kids back in school, cooler weather approaching, and more activities taking place indoors, the not-so-welcome cold and flu season is also upon us. This year in particular, with our extreme alertness to anything viral and/or respiratory, it’s more necessary that we keep ourselves aware of the possibility of getting sick—and be proactive about taking steps to keep ourselves healthy.

To be honest, when I started my research for writing this post, I expected to find evidence of clear trends and some near-conclusive evidence of one or two driving factors behind the annual cold and flu season. What I actually found was far from clear or decisive. Many illnesses exhibit seasonal trends (i.e. respiratory infections increase from October to March or April, then take a downturn), and every season in every major geographic region has its bugs. But science doesn’t have a clear grasp on why.

So rather than trying to explain that why, I’ve decided to give you some of my lesser-known tips for boosting your immune system. That way, you have some tangible tools to try today to help keep you and your family healthy all season long. 

Get a Dog

(Okay, fine, a cat will work too—but I’m very partial to dogs.) Pets are naturally dirty. They carry with them a host of bacteria that are not otherwise present in human homes. They also produce dander and other microscopic matter.

I know, I know. All of these sound like great reasons not to have a dog if you’re trying to avoid getting sick. The truth is that it’s the exposure to these minor immune challenges that strengthens our immune systems and makes us better prepared to appropriately respond to other irritants and pathogens.

Early life exposure to dogs has been shown to decrease incidence of allergies and asthma. Dog ownership has also been tied to decreased incidence of heart disease, lower blood pressure, increased life satisfaction, and lower stress levels.

Even petting a dog has been shown to increase levels of some immune chemicals, decrease cortisol (the stress and alertness hormone) levels, and increase levels of oxytocin (the trust and bonding hormone). That’s part of why therapy dogs work.

Go for a Walk Outside Every Day (Yes, Even the Cold Ones)

In case you need another solid reason to have a dog, moderate exercise has been consistently shown to increase overall immune function. What’s important here is the word MODERATE.

Too mild—say a leisurely stroll around your favorite Target—is not enough to get the immune system going. Too strenuous—say running an ultra marathon—will deplete your system and leave you less able to fight pathogens.  

The Goldilocks zone is where your heart rate goes up, you’re breathing hard enough that you can’t quite carry on a conversation while you’re doing it, and you can still walk away in the end with enough energy to go back to work, have family time, or maybe fight off a virus (wink, wink). This will obviously vary with your fitness level.  

One suggestion from the science is brisk, daily walks. This doesn’t mean you have to throw on your 1980s tracksuit and fanny pack to go power walking (unless that’s really your thing, in which case—you do you). A 30-minute outdoor walk at a pace that’s fast enough that it’s difficult to carry on a conversation, and slow enough that you don’t feel winded is just what the doctor ordered (maybe while taking your dog for a walk… just saying). 

Consider Boosting Your Vitamin D

Yet another benefit of the outdoor walk is direct skin exposure to sunlight and vitamin D. The benefits of vitamin D on the immune system have been widely discussed recently, but not everyone produces sufficient vitamin D levels. People in northern latitudes tend to suffer deficiencies, especially in the winter and early spring, but it goes beyond that.

People of color also tend to produce less of the vitamin in response to sun exposure. This is presumably because skin with more pigmentation is usually a genetic adaptation to high sun exposure, which would require less efficient creation of vitamin D. If you’re a person of color who also lives in a northern latitude, you’re susceptible to a double whammy of vitamin D deficiency—low sun exposure and a predisposition to producing less.

If this is you, spending time outside without sunscreen, which blocks the UV light necessary for creating Vitamin D, is a great place to start. Try 30 minutes of direct sunlight to reap the benefits.

There are also a few genetic predispositions that can cause people to have difficulty producing vitamin D or converting it to its active form. If you suspect your body isn’t adequately producing this vitamin, or you consistently have low levels of vitamin D in your bloodwork, a genetic test (like 23 and Me) can help illuminate possible causes.

Supplementation is always an option if you have challenges with vitamin D production. The recommended daily dose is 600IU of vitamin D3 (the activated form our bodies can use), but up to 2,000IU tends to be well tolerated.

Cholesterol levels are another factor when it comes to vitamin D conversion. Vitamin D, like many of your body’s hormones (including sex hormones), is derived from cholesterol. Too little cholesterol means your body won’t be able to produce vitamin D, no matter how much sunlight you get.

Vegetarians and vegans are at a higher risk for this type of deficiency, as there are no plant-based sources of usable cholesterol. Plants have a cholesterol equivalent called phytosterols, which human bodies can use for some functions, but not for creating elastic connective tissues, hormones, or vitamin D.

Since the only naturally occurring sources of vitamin D are mushrooms (and you should toss those edible varieties into meals where you can), vegans and vegetarians also benefit from sun exposure. Supplementation isn’t as great of an option, since most vitamin D capsules are animal derived, and I don’t recommend adding vitamin-fortified processed foods into your diet. I would also seriously consider adding ethically sourced fish and/or krill to your diet to provide the fats necessary for healthy body functions.

Expose Yourself to Nature

Walks outdoors increase activation of the immune system across the board. Not only does exposure to green plants lower stress hormone levels, but being in nature also exposes you to naturally occurring viruses, bacteria, and fungi. These provide your body with the chance to deal with low-grade challenges and tune your immune system for appropriate responses to these particles.

Bonus: plants filter pollutants out of the air and produce oxygen in exchange for our carbon dioxide, helping to stave off respiratory issues.

Ditch Your Dishwasher

Using a dishwasher to clean your home dishes is correlated with an increase in chronic diseases, especially allergies, later in life. Why? Dishwashers might sterilize your plates and silverware a little too well.

Both this and pet ownership are believed to be part of the “hygiene hypothesis,” the idea that exposure to a variety of bacteria, fungi, and other pathogens (especially early in life) creates an immune system that is more capable of mounting appropriate responses to all types of pathogens. This means fewer allergies (a hyper response to a harmless stimulus) and fewer acute infections (presumably due to the more responsive immune system).

Under this hypothesis, our perpetually scrubbed, sterilized, and sanitized artificial environments are so clean that our immune systems are not afforded the opportunity to develop. We rely on minor pathogens like those that our dishwashers sterilize away to train our immune responses and to populate the biomes of our gut, skin, hair, and mouths with a variety of good bacteria. So, a few times a week, wash your dishes by hand (and definitely turn off the “sterilize” function on your dishwasher). 

Get Body Work

There’s an increasing amount of evidence that supports practices like chiropractic and massage for immune health. Some research targets specific chemical pathways, trying to figure out what mechanisms behind such types of physical touch might stimulate or inhibit parts of the immune response. Others have pursued the theory that better general body health is contributing to improved overall function of the immune system.

Truth be told, this is probably a “both and” scenario. People who receive regular body work tend to have higher overall quality of health. They also tend to be more aware of their bodies and are more likely to perceive the early warning signs of illness and take steps (like the ones listed here) to prevent it from progressing into a full-blown illness.

Increase Physical Contact with Trusted Others 

It might sound silly, but a good hug can work wonders for boosting your immune system, for multiple reasons. Physical contact with trusted people boosts your oxytocin (trust and bonding hormone) levels and decreases your cortisol (alertness hormone), which serves to increase your feeling of well being and decrease your stress levels.

Get Quality Sleep

Sleep is one of the most important things you can do for all areas of your health. The human body relies on this 7 to 9-hour rest period to clean up toxins that have built up during the day, repair and regrow tissues, store memories, and create the immune cells needed to fight off invaders.

Sleep has many facets that deserve more space than I can provide here. To improve your sleep quality, check out my Top 10 Tips to Sleep Like a Boss. 

Manage Your Stress

Like a trial run, training, or a scrimmage, “good stress” or hormetic stress helps the body adapt to more effectively deal with stress. If we don’t test our bodies’ ability to respond or heal, we won’t develop the ability (use it or lose it).

However, if we miss the “good” target and go too far, we can overwhelm our systems and cause a disordered state, or teeter into chronic stress territory. The tricky bit here is that the hermetic or “good” range is different for everyone and changes over time.

Cortisol and other stress-response hormones like norepinephrine and adrenaline are normally part of appropriately stimulating your immune system to act. However, when cortisol is consistently elevated (a.k.a. when you’re experiencing chronic stress), your immune system becomes desensitized to it (like a diabetic being desensitized to insulin). In short bursts, these hormones help your immune system function well. In long, drawn-out spells, they create dysfunction of the immune system.  

That’s why being in tune with your body’s reaction to stress is important. Certain foods, environmental exposures, or exercise can activate your body to strengthen its ability to deal with stress. But if you find yourself suffering from out of the ordinary pain, fatigue, digestion issues, or other recurring problems, you might have pushed yourself too far (and you can learn how to manage your stress here).

If you’re interested in pursuing specific-to-you immunity boosters, reach out. Chiropractic work and a personalized wellness plan can help protect you and your family from illness this season (and beyond).