7 Ways to Improve Your Immune SystemDr. Miranda Wiley, ND
October 14, 2022
I spluttered on a sip of water while watching my kids at the playground and found myself madly asserting “It’s not Covid! It just went down the wrong way!” through my coughing fits. In 2019 no one would have thought twice about reassuring those standing near them that they were in fine fettle while dealing with sneezes from allergies, or coughs from quasi-choking on food, but that was pre-pandemic. Here we are in the “new normal” with an ongoing desire to improve our immune systems, particularly as we head into winter, while adjusting to all the changes that happened in our personal, local, and global communities over the last 2.5 years.
While the panic around Covid is settling, concern about immune health continues for many people. Advice on how to “boost” the immune system still abounds but the immune system is so beautifully complex that “boosting” it is a bit of a mislabel. In cases of allergy or autoimmune disorders the last thing we need is a stronger immune response! Better, I think, to focus on immune balance, immune strength, immune resilience, immune modulation, immune health… simply improving our immune system so that it is the best it can be.
Do I need to improve my immune system?
The immune system is comprised of a range of white blood cells that all have their unique roles to play. At times it is necessary for the immune system to spike inflammation to allow white blood cells access to an area of trauma or infection, while at other times it works to remove inflammation so that function to that tissue can be restored. A balanced immune system allows for all of these interplays to happen at the right time and in the right order. A poor immune systems fails to protect us from the myriad of circulating colds and flus, or leaves with ongoing inflammation long after the danger has passed.
Allergies, autoimmune disorders, inflammatory illnesses (anything ending in “-itis” such as arthritis, bronchitis, cystitis), chronic illnesses, or recurrent illnesses (“I catch everything going around!”) are all indications that the immune system needs some support.
Factors affecting immune resilience
From keeping our hands clean to improved respiratory etiquette, our personal hygiene is a priority in improving our immune system. We can’t avoid all microbes, but washing our hands regularly will naturally limit our exposure to potentially harmful pathogenic viruses and bacteria.
Immune function appears to have daytime and nighttime actions indicating a strong relationship to our sleep-wake cycles, the circadian rhythm.  Likewise, signals sent out by the immune system can have a direct effect on our sleep: “Sleep disorders are commonly associated with chronic inflammatory diseases and chronic age- or stress-related disorders.” 
If sleep is not a current priority but immune health is then it’s time to refresh your relationship with sleep. Setting a regular bedtime as well as wake up time are an essential foundation to a balanced, well-functioning immune system.
If you suffer from insomnia then working with a professional with experience in supporting nightly, restorative sleep is a good idea. As suggested above there may be an underlying immune imbalance that needs to be addressed!
Also correlated to our circadian rhythm is cortisol, a key stress hormone. Many people have used or heard of corticosteroids for reducing inflammation – creams for eczema, puffers for asthma, or pills for wide spread inflammation. The cortisol that we produce ourselves also has anti-inflammatory and immune regulating effects. 
Cortisol is released in a fairly predictable daily pattern where it’s highest in the morning and after meals, and lowest at bedtime and while we sleep. Chronic and acute stress alters our immune function with acute stress helping to protect us from infection, and chronic stress decreasing the efficacy of our immune system  making us more susceptible to illness.
While some sources of stress are beyond our control (for example, a pandemic and the ensuing restrictions!) we can work to support our physical and emotional reactions to external stressors. To that end, mindfulness meditation is under investigation as a useful tool for supporting immune function during times of stress. 
A wide range of whole food nutrients are involved in overall optimal immune function. Vitamin C, vitamin D, and zinc have the most evidence for immune support benefit. 
Vitamin C is highest in fresh produce. Vitamin D is predominantly found in meat, organ meats, fortified dairy/juice products , and UVB-exposed mushrooms.  We are able to synthesize our own vitamin D from sunlight exposure on our skin indicating that supplementation may be more beneficial in winter months than during the summer.
Zinc is found in shellfish, meat, and legumes. 
Astragalus is a herb with a long history of use in Traditional Chinese Medicine where it is used to build “defensive Qi” (essentially “immune energy”).
When we’re healthy we need to move our bodies to some degree every day. Whether that be walking (gentle or brisk), a dance party in the living room, or an exercise class then “motion is the potion” to keep us young, supple, and healthy. Lymph, which carries immune cells, is carried along vessels similar to the blood vessels but it isn’t pumped by the heart so it requires muscular contraction and relaxation (physical activity) to move it.
When we’re ill the focus is on rest but we can still work in some gentle stretches to help move lymphatic fluid until we’re fully recovered.
Water is necessary for the movement of nutrients into cells, waste out of cells, and immune cells throughout the body. Imagine washing your hair but not rinsing away all of the shampoo! Yuck. Sufficient water throughout each day keeps cells hydrated and allows waste removal through sweat and urine.
Caffeine and alcohol encourage us to excrete water but a squeeze of lemon juice or herbal teas are a lovely way to take in more fluids whether we’re healthy or ill.
7. Digestion and gut health
When looking at the immune system we really must give credit to the trillions of beneficial flora (health supporting bacteria, yeast/fungi, and viruses) that live in and on us!
Altered immune function can cause a disruption in our good bacteria, and conversely, changes to our microbiome can contribute to immune dysfunction. For long-term immune resilience we need to be mindful and proactive about our microbiome; supporting healthy microbes and minimizing the growth of disease-causing ones.
A whole foods, fibre-rich diet that includes some naturally fermented foods is a good foundation for our trillions of microbes residing along our digestive tract. Digestion is also supported by good hydration, regular activity, restorative sleep, stress management, and proper hygiene! Holistic health comes full circle…
So embrace the changing of the seasons and be mindful of which areas of your health and lifestyle could be fortified in order to improve your immune system. Do you need to bump up your veggie intake? Do you need to reprioritize sleep or practice setting boundaries at work to keep stress down? Would you benefit from a glass of warm water with lemon juice on rising?
Do you need more immune nutrients? Celebrate your successes and do what you can to optimize your immune system so that you can enjoy the months ahead with minimal interruption from the circulating infections in the world.
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