Meet…Your Immune System
Most people seem to conceptualize their immune system as some sort of abstract defense against invaders that cause things like the cold or the even-more-dreaded flu.
Others know it as the root of their afflictions like hashimoto’s or any number of increasingly common autoimmune conditions. Any one-sided and simplistic perception of the immune system as a sort of rigid barrier that can’t be purposefully and beneficially influenced is a fundamentally false one – there is a lot that we can do to both support our immune system and to sabotage it. Building a solid immune system isn’t extremely complicated, but it can take quite a bit of work and require lifestyle changes. No single factor is going to make our break the force shield that we like to call our immune system, but we can definitely provide the entire network of organs, specialized cells, chemical messengers, and more with some support to help it work as well as it possibly can.
To help drag the concept of our immune system from the abstract to the more practical, we should start by quickly covering some basics of the immune system to begin painting a picture of it as the dynamic and malleable entity that it truly is. After that, stay tuned for some ways to support your overall immune system function like getting enough sleep and eating some key nutrients, as well as a few major sources of friction that many people are creating unnecessarily in their lives. Your immune system is incredibly complex, and its capabilities and limitations are dependent on far too many variables to cover today, but what we want to focus on are practical strategies that you can begin incorporating into your life today to start developing your immune system into an intelligent and precise fighting machine. There is no way that we can fully thank our immune system for protecting us from infection by unfriendly bacteria or viruses, or for zapping cancer cells before they can spread – the most we can do is support it along the way!
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What Is The Immune System?
They say knowledge is power, and becoming aware of some of what makes up your immune system is extremely helpful in understanding exactly how, and why you can support it in the fight against all kinds of would-be invaders.
Although a complete and thorough description of the components and functions of the immune system is far beyond the scope of this article, there are some helpful distinctions that can illustrate just how complex it is. First, your immune system can be broken down into a few major parts: the innate immune system, which is composed of things like skin, cells of the GI tract, eyelashes, and other obvious physical barriers as well as more subtle built-in mechanisms like inflammation, gastric acid, and various other cellular responses. Then you have your adaptive immune system which is what seeks out specific pathogens, eliminates them, and creates a lasting memory of them in case you encounter them in the future. This side of your immune system is made up of many different specialized cells that all work together – a classic example of how this works would be your response and subsequent immunity created when vaccinated.
Arguably the most important component of the human immune system, and one that is extremely influenceable, is the lymphatic system.
Your lymphatic fluid is what circulates vital immune components known as white blood cells, as well as functioning to allow the body to eliminate toxins, waste, and other unwanted materials. There is definitely a major design flaw with this system though, in that it does not get directly pumped like your blood does – bodily movement and muscular contractions are what pushes your lymph around. This is just one of the many reasons why exercise is absolutely crucial to optimal immune function, as we will discuss later. As you can see, your immune system is composed of many parts that all work together to protect you from cancer, bacteria, viruses, and much more. Unfortunately, there are many common lifestyle habits and practices that are utterly opposed to optimal, or even effective immune function.
What Can Kill Immune Function
Knowingly or unknowingly, many Americans stomp down their immune system function like a schoolyard bully on a daily basis. Less-than-healthy habits such as not sleeping enough and eating carelessly can damper the capabilities of your immune system to protect you from any number of unwanted experiences. By essentially tying your immune system’s hands behind it’s back, you are going to be setting yourself up for failure. Some of the factors that may suppress immune system function include:
- Not getting enough sleep or having an otherwise disrupted circadian rhythm.
- Lack of movement/exercise (resistance training is especially beneficial for overall health).
- Diet lacking in micronutrients (our immune system needs certain vitamins/minerals to function properly).
- Chronic stress or other unmanaged cognitive/psychological dysfunction.
Fortunately, most of what you can do to support your immune system comes down to avoiding these major sources of friction as much as possible, as well as generally living a health-focused lifestyle. There is an overabundance of research indicating that you do in fact have profound influence over your body’s ability to ward off disease and dysfunction.
The Importance Of Sleep
Arguably the most important thing that you can do to support your immune system is to get enough quality sleep.
Our immune cells have a day/night cycle just like the rest of our physiology, which results in the immune system being highly active (from a circadian biology perspective) during the rest and recovery time provided by nightly sleep. Because of that fact, the activity of certain immune cells varies immensely between day and night. Basically, if you aren’t sleeping enough, you can bet your immune system isn’t firing on all cylinders.
In a fascinating study investigating the effect of sleep deprivation on immune function, it was found that not getting enough sleep will negatively impact your immunity on many levels and to varying degrees. Further research has found that sleep restriction causes:
- chronic low-grade inflammation
- decreased natural killer (NK) cell activity
- hormonal dysregulation
- and eventually, immunodeficiency
None of these are favorable for optimal immune function. Slow-wave sleep is especially important to the health of our immune system, and mechanisms that allow your body to identify pathogens or other invading cells is especially enhanced during this part of the sleep cycle. If you are already getting between 7-9 hours of quality sleep each night, and you wake up feeling rested each day, the next most important factor to focus on to support immune health is ensuring you are getting adequate nutrition from your daily diet.
By now we likely don’t need to remind you just how complex your immune system is.
There are countless variables that can impact this system, and nutrition is definitely one of the major ones. Many of the cells, enzymes, chemical messengers, and hormones that work away for your immune system require certain micro- and macronutrients for them to function properly. What this means is that ensuring you get enough vitamins, minerals, antioxidants, fats, and amino acids (in particular those that are essential to immune function) is one of the best strategies for supporting your overall health and resilience to disease.
Some of the more important nutrients for immune system function include:
- vitamins A, C, D, B2, B6, B9, and B12
Poor nutrition can clearly compromise immune function and increase infection risk as well as the likelihood of severe infections. Luckily, you can absolutely improve immune function by patching up any holes in your diet, or with added supplementation if needed. Here are just a few of the major micronutrients that can deeply impact the capabilities of your immune system:
- Vitamin D: Vitamin D levels are notoriously low in America, and it is no surprise that D can have an enormous impact on your immune health – both good and bad. Low levels of Vitamin D are especially detrimental to immune function due to the fact that it binds to, or interacts in some way with many immune cells such as B cells, T cells, and antigen presenting cells (APCs). This powerful vitamin/hormone has the ability to modulate the innate and adaptive immune responses, and should likely be taken by everyone on a daily basis depending upon a variety of factors.
- Zinc: Zinc is a heavy-hitting mineral that is crucial for immune function and depletion of this key nutrient has been associated with many adverse events. For example, zinc deficiency can enhance atrophy (shrinking) of the thymus, decrease immune cell number and activity, and increase oxidative stress and inflammation by altering production of cytokines. As a result, your ability to fight off infections is dramatically reduced.
- Vitamin C: Although it might sound obvious, Vitamin C is actually rather important for immune function. During infection, disease, or even chronic, the rate at which you produce reactive oxygen species is increased. This boost in ROS production further depletes vitamin C stores, requiring you to get even more than usual from diet or supplementation. Vitamin C is also crucial for modulating the inflammatory process, and has other roles within the immune system.
We typically recommend getting as much of your nutrition from whole food sources as possible. However, supplementation has absolutely been proven effective at boosting immune function if you are deficient in any of these key micronutrients. It is important that you keep in mind though, that adding in supplements likely won’t make much of a difference at all if you are not managing the other major sources of friction that can reduce immune function. Chronically elevated stress levels for example, are notoriously good at throwing a major wrench in things.
Reducing your level of overall stress is one of the most impactful things you can do to positively influence the ability of your immune system to protect you from invaders and dysfunction.
Normal, acute increases in the sympathetic (fight or flight) stress response undoubtedly has the ability to cause potentially beneficial changes in immune function (like activation of detoxification pathways from exercise, heat stress, or caloric restriction). Once any stressful experience becomes overwhelming or too frequent however, all kinds of dysfunction can emerge. The infamous stress hormone cortisol is actually a potent antioxidant that is required to make certain the immune system or inflammatory response is appropriate and under control. If cortisol is chronically elevated, as it is with unmanaged stress levels, your body (more importantly some kinds of immune cells) become desensitized and down-regulate their receptors for it. This is just one example of the physiological adaptations that can occur due to chronic stress and how they may limit your immune system capacity. Other psycho-social factors such as social isolation and depression have also been shown to negatively impact immune function.
To begin controlling your stress levels, a meditation practice has been proven effective time and time again. Interestingly, not only has meditation been proven to reduce stress in peer-reviewed research, it has been directly associated with increased immune function. In a meta-analysis looking at many randomized controlled trials (totaling 160 subjects) it was found that many markers of immune health were vastly improved by simply engaging in a mindfulness meditation practice. Researchers observed:
- decreases in Nf-kB activity (pro-inflammatory molecule)
- an increase in telomerase activity (DNA protective enzyme)
- a decrease in levels of C-reactive protein (marker of inflammation)
- an overall increase in many parameters of cell-mediated immunity.
These findings were not the first to suggest that reducing overall stress can aid in immune function. It is hardly controversial to suggest that having a positive mindset is an incredibly important factor to sway the outcome of various disease-states in a more favorable direction. One of the final pillars in developing a robust immune system is consistent movement and (hopefully) exercise.
Exercise And Immune Health
Exercise, and in particular resistance training, has the ability to positively impact your immune system on many levels.
At minimum, some form of movement is required for the circulation of lymph fluid (your lymphatic system doesn’t have a pump, instead it relies on your physical movement and contracting muscles). In contrast, too much exercise can result in overtraining which can be just as bad as not exercising at all – if you are wanting to stay healthy. This is why resistance training that is appropriate (for you), and the resulting increase in lean body mass, is likely your best route for improving immune function. Unsurprisingly, increases in lean body mass has been shown to result in more favorable outcomes from all kinds of health problems – in fact, the importance of utilizing muscle mass as a new vital sign is becoming increasingly obvious.
Scarily, the expected and preventable decrease in lean body mass (sarcopenia) that comes hand-in-hand with the aging process can result in:
- increased risk of infection
- slower wound healing
- increased risk of pneumonia
- enhanced risk of osteoporosis and fractures
- many more undesirable effects.
But that doesn’t mean that you absolutely have to start lifting weights in order to boost your immune system – simply moving more throughout the day can increase the circulation of your lymphatic fluid and result in more robust defense capabilities. Combining relatively frequent resistance training with a good amount of daily low-level movement (get off the couch!) will ensure that you are getting the best of both worlds.
Last Word On Immune Health
Our immune system is always working, day and night. And the things that we do, or don’t do, can have profound implications on its ability to protect us from potential invaders. It is up to each of us to make sure that the habits and practices we implement in our daily lives are going to support this defense system in the fight against unwanted bacteria, viruses, cancerous cells, parasites, funguses, and more.
No single factor alone will completely make or break your immune system, but consistently getting enough sleep, exercising, eating the right food, and managing stress are all crucial aspects to ensure your immune system isn’t going into a fight that it is rigged to lose.