Nutrition, Lifestyle, and Supplement Guide to Supporting your Immune System.
There is a war going on. You may not know it’s happening, but it’s happening 24/7, and it’s going on inside of you. Your immune system is constantly active; surveilling your blood and tissues, on high alert for any pathogen or bad bug that might be present.
And they’re always present. Some more easily defeated and benign than others, but others take all the reinforcements that your body has, ramping up your response into high gear.
Did you know that a fever is caused by your own body’s immune system in an attempt to kill the virus or bacteria? That’s why, although it makes you temporarily feel better, taking a fever reducer like acetaminophen or ibuprofen can result in the sickness lasting longer. But that’s a different topic altogether.
It’s easy to really see how many pathogens we come into contact with every day in cases of severe immunodeficiency, such as advanced cases of AIDS, where these patients will get strange and rare infections that people will never normally contract.
Immune System Basics
Innate Immune System
The first level is called the innate immune system. This system provides a quick first line of defense and acts against a wide range of pathogens.
The innate immunity system refers to nonspecific defense mechanisms that come into play immediately or within hours of an antigen’s appearance in the body.
These mechanisms include physical barriers such as skin, chemicals in the blood, and immune system cells that attack foreign cells in the body. The chemical properties of the antigen activate the innate immune response.
Cells of the innate immune system include natural killer cells, macrophages, mast cells, basophils, and eosinophils.
Adapative Immune System
You know how once you get something like the chicken pox, or even this year’s circulating flu, you can’t get it again? This is due to the adaptive immune system.
The immune system creates a “memory” – after infection of pathogens that are novel to the body, the body builds up troops and keeps those troops in reserve in case you ever get infected by the same pathogen again. These are memory T cells.
The adaptive immune response is more complicated than innate. The antigen (anything causing an immune system response) first must be processed and recognized. Once an antigen is identified, the adaptive immune system creates an army of immune cells specifically designed to attack that antigen.
Some adaptive immune cells include T and B lymphocytes.
T-cells attacking a pathogen.
Where Our Immune Systems Can Struggle
Chronic inflammation is one causal factor in most every modern-day chronic disease, such as type 2 Diabetes, Alzheimers, cancer, and heart disease.
Chronic inflammation also causes higher susceptibility to certain diseases by over-activation of the immune system. Inflammation in general is the immune system’s response to a bodily insult or injury.
Huh? Say what? You’d think if the immune system was in a hyper-active state, you’d be less susceptible to diseases. But in low grade chronic inflammation, this isn’t the case.
If you’re constantly causing low grade damage to the body through consuming inflammatory foods, being in an inflammatory environment, etc, in a sense, you’re redirecting resources and causing other types of immune system dysfunction leading to higher susceptibility to pathogens (viruses, bacteria, etc).
There are many different mechanisms for this, but pro-inflammatory mediators can activate immunosuppressor cells such as MDSC’s.
MDSC’s are basically the pre-cursor to many innate immune system cells such as macrophages, dendritic cells, and granulocytes. Whenever the expansion MDSC’s occurs, it disrupts the aforementioned innate immune cells from maturing. Less innate immune cells = lower immunity.1
In a large cohort study of >15,000 individuals over 3 years, low-grade inflammation (as defined by hs-CRP between 3 – 10) was associated with increased hospitalization for infection and highly increased anti-microbial prescription rate.2
Increased stress, whether physical or psychological, increases cortisol. This could be from lack of sleep or perceived threats (everything from work due dates to the tiger in the room).
Cortisol is one of the body’s primary fight-or-flight hormones which wakes you up in the morning, gives you energy, and suppresses inflammation and thus the immune system.
Say you’re an athlete or even a recreational exerciser and you’re dealing with some chronic pain of some sort – knee pain, ankle pain, etc. Or maybe you even sprained your ankle.
If the pain isn’t too bad, you may push through and still go for that run. During the first 6-8 minutes, you may notice it still hurts decently bad. But after that, the pain starts to go away. One of the reasons is because of the cortisol increase you experience during physical exertion.
I personally remember when I’d injured my low back 8 or 9 years ago, I was prescribed corticosteroids (medical cortisol, basically) for a short time and I went from taking a full 5 minutes to get myself out of bed to doing moderately heavy deadlifts while still injured (like an idiot, don’t do that).
Well the pain was caused by inflammation, and corticosteroids suppress that inflammation by suppressing the immune response.
An appropriate amount of cortisol is necessary for life. If we didn’t have it, we’d be dead. However, chronically elevated cortisol makes us susceptible to a host of diseases by suppressing the immune system.
If you’re interested in some mechanisms, elevated cortisol inhibits T-cell (adaptive immune system) proliferation, directly inhibits natural killer cells (innate immune system), and stimulates superoxide dismutase (SOD).3,4
SOD nullifies the free radical superoxide and turns it into oxygen. Now, you might be thinking that this is a good thing since you’re nullifying free radicals which are known to cause all sorts of damage.
However, free radicals do play an important positive role in the body. It’s only when they get into places and compartments in the body that they’re not supposed to be that they cause damage.
The free radical superoxide, when in a controlled environment with everything working properly, plays a very large role in poisoning bacteria and pathogens without reacting with other bodily molecules negatively.
Independent of sleep loss increasing cortisol which can suppress the immune system, some very important processes occur for your immune system during sleep.
As I spoke on earlier, T-cells are part of the immune systems adaptive branch; they start out “naive” when created, and when a new virus or bacteria that your body hasn’t seen before occurs, they “remember” the infection and build up antibodies towards it to prevent infection next time.
Sleep affects these: New, naive T-cells are created during sleep. So less sleep equals less new T-cells. The memory process I spoke of earlier where T-cells become mature and contribute to immunological memory occurs during sleep as well.5
How Can We Support and Optimize Our Immune System?
Nutrition and Supplementation
Everything we put in our body either increases inflammation or ameliorates it. There are no neutral foods except for water.
The immune system is centered in the gut. This means anything that you eat that is causing gut inflammation is causing some sort of dysfunction of the immune system, whether mild or severe. And gut inflammation reaches systemic circulation, meaning it reaches whole body circulation (including crossing the blood brain barrier and causing brain inflammation!).
With that, we have to get the basics out of the way. Stop it with the processed, packaged, foods. Especially processed carbohydrates. There are so many things wrong with those, it’s hard to cover in a single post.
The fast-digesting attributes, the preservatives, emulsifiers, etc. From causing massive blood sugar spikes, to damaging the gut, to numerous other effects. It’s basically an orchestra of haywire whenever you consume these things in excess. And they’re engineered to be addictive, so chances are, if you’re consuming them, you’re doing so in excess.
As stated above, these can wreak havoc on the gut and therefor disrupt the immune system.
Beyond those basics, things that can cause gut inflammation are fairly individual from person to person. Here is a spectrum of intolerances taken from Dr. Ruscio’s Healthy Gut, Healthy You:
For a little clarification on the picture, foods on the left under the “Most tolerated” list are still common intolerances – they’re just the least common of the common intolerances, if that makes sense.
Beyond this, people can still have intolerances to specific foods not on that list. The best way to go about finding this out is to make a food awareness diary.
Record what you eat, how you feel within the next few hours as in digestive discomfort, mood, focus, energy, etc. Record how you sleep. After a week or two of data, look back and start to identify trends, and eliminate suspect foods for at least a month.
For a much more in-depth look at this, and protocols on how to heal your gut and identify your individual intolerances, check out Dr. Ruscio’s Healthy Gut, Healthy You (no affiliation). It’s a great guide to all things gut.
Now let’s talk about fats. It’s pretty much mainstream knowledge these days that certain added fats are extremely inflammatory and should be avoided. I’ll summarize by providing a picture of the PDF I include to all of my clients:
Inclusion – Supplements, compounds, and the foods that contain them
Now that you’ve removed the foods causing some degree of immune system suppression, we can look at foods and supplements that support the immune system. I’m going to outline the specific compounds known to increase or support immunity, and then foods that contain them and supplemental doses.
Astragalus has been shown to stimulate and activate T-cells.6
When most people think of vitamin D, they think of calcium and bones. Well, vitamin D goes way beyond those functions. It is in control of over 1000 genes in the body, modulating everything from mood to energy to – yes – the immune system.
Alot of immune cells have the vitamin D receptor on them (B, T, and antigen presenting cells) for vitamin D to exert it’s effects. Low vitamin D levels have been strongly correlated to increased susceptibility to infection and increased incidence of autoimmunity.7
If you don’t get a lot of sunlight on your bare skin during the day (and even if you do, to be safe), 2000 IU/day is a good number to supplement with.
Vitamin A is crucial to so many aspects of immune system function. Research has shown that our immune systems need a constant supply of vitamin A incoming to perform many functions.
It plays a big role in the creation, maturation, and function of all innate immune system cells. Deficiency has been shown to cause lower numbers and dysfunction of macrophages and neutrophils.
It plays a big role in the adaptive immune system as well – vitamin A regulates bone marrow homeostasis in a positive way. T-cells from the adaptive immune system originate in the bone marrow, and vitamin A deficiency has been shown to lead to defects in all t-cell mediated immune responses, including t-regulatory cells (cells that police the immune system and make sure it’s not attacking your own body).8
I would recommend getting vitamin A mostly from animal sources, since it’s already in it’s active form of retinol. Whereas plant sources contain a form that has to be converted to retinol, and many individuals have genetic polymorphisms preventing them from converting plant vitamin A to retinol.
Sources of (retinol) vitamin A include: Liver (beef and lamb), mackerel, salmon, tuna, goat cheese, aged cheddar, Camembert, eggs, and butter.
Sources of pro-vitamin A (precursor) include: Sweet potato, carrots, winter squash, kale, collards, turnip greens, red bell peppers.
Vitamin C has been shown to bolster the immune system in many aspects. It supports the barrier function of all epithelial (skin, all surface tissues basically) barriers against pathogens and increases anti-oxidant activity.
It builds up in both macrophages and neutrophils of the innate immune system, enhancing their ability to scavenge pathogens and neutralize them.
It also aids in clearing out used up and near-dead neutrophils (innate immune cells), keeping the immune system “clean” and in better shape in general.
It has been shown to increase proliferation of both B and T cells, and has been used successfully to treat respiratory and systemic infections.14
Good food sources of vitamin C include citrus fruits, canteloupe, mangos, broccoli, Brussels sprouts, cauliflower, green and red peppers, spinach, cabbage, turnip greens, and other leafy greens. However, higher supplemental doses are recommended for increasing immunity.
Supplemental doses of vitamin C range largely – from 1000mg (1g)/day, up to 10,000mg (10g)/day. The half life of vitamin C in the body is 30 minutes, so during times of high infectivity (cold or flu season), I have personally had great success with dosing 2000mg of vitamin C 3 to 4 times daily. I haven’t been sick – not even as much as a cold – in about 7 years.
Zinc is also huge for the immune system. Zinc is crucial to the development of all innate immune cells.
It plays a large role in immune memory of the adaptive immune system by regulating the activation of T lymphocytes, Th1 cytokine production, and recruits helper B cells.
It also plays a large role in B lymphocyte development and antibody production (particularly IgG).15
Zinc has also been shown to prevent viruses from proliferating within cells.
Zinc is high in foods such as oysters, red meat, crab, mussels, chickpeas, lentils, and beans in general.
Supplemental zinc – A good brand of supplemental zinc is Jarrow Zinc Balance. However, I think you should also have Zinc Acetate Lozenges on hand as well. Zinc Balance should be the daily supplement. At first sign of a “scratchy” throat or feeling any sickness like that, let zinc acetate dissolve in your mouth over the course of an hour.
Chlorella has been shown to increase salivary IgA a significant amount compared to placebo; suggesting a significantly enhanced mucosal immune response.9
A good supplemental dose of chlorella (make sure you get a product thats organic with a cracked cell wall) is 6-10 tablets/day.
Eleuthero (Siberian Ginseng)
Two names for the same thing, eleuthero has been shown to stimulate both T-cells of the adaptive immune system and natural killer cells of the innate immune system.10
Doses of standardized extracts used in studies have ranged from 1.2g – 4g. 2g/day would be a good sweet spot.
Reishi Mushroom Extract (Ganoderma lucidum)
Reishi mushroom extract (Ganoderma lucidum) has been shown to strongly influence the proliferation of both T-cells and natural killer cells, and has strong anti-cancer activity.11
Doses used in research to show effects have ranged from 1 – 5.4g of standardized extract. A good middle ground to ensure you’re getting effects would be 3g of a standardized extract/day.
Holy Basil (Tulsi)
Holy Basil has been shown to increased proliferation of T lymphocytes and T cytokines.12
Studies with Elderberry extract has shown a lot of positive results – from mechanistic studies to in vivo (human studies). It, like zinc, appears to prevent viruses from replicating within cells by blocking important viral glycoproteins.
It modulates the immune system by stimulating cytokines.
It has been specifically shown to minimize the effects of influenza infection, and has a modest effect in the pre-infection phase, but a very robust effect in the post infection phase.18
Nigella Sativa increases innate immune system activity – It increases macrophage killing potential and phagocytic activity. In other words, it increases the ability of macrophages to suck up pathogens and neutralize them.13
The dosage used in studies was 2g of a standardized extract/day.
Garlic extract, specifically stabilized allicin at 180mg, has been shown to be very anti-microbial, specifically against bacterial infection in studies.
Mechanistically, it has been shown to stimulate macrophages by activating them and increasing their phagocytic activity, lymphocytes, natural killer cells, dendritic cells, and eosinophils. It modulates cytokine production and immunoglobulin secretion.16
As stated earlier, efficacious doses in studies were 180mg of stabilized allicin/day. If using a regular garlic extract, 3-5g a day is appropriate.
N-Acetyl Cysteine (NAC)
NAC is the precursor to the body’s master anti-oxidant – glutathione. NAC supplementation has been shown to improve all aspects of lymphocyte and neutrophil function, as well as modulate cytokine levels in a positive manner.17
Doseages used in studies were 600mg NAC/day.
Lifestyle Practices to Support Immunity
As stated earlier, I talked about how sleep deprivation damages immunity, thus proper sleep will support and maximize it.
Shoot for 8 hours of largely un-interupted sleep per night. Struggle with sleep? Here are a few tips.
Get more sunlight during the day. This aligns and strengthens your body’s circadian rhythm.
Avoid blue light after sunset. Blue light is emitted from LED lights and any screen you may watch. Blue light inhibits melatonin secretion; one
of the body’s primary sleep hormones. Wear blue-blocking glasses after dark. Download filter programs on your computer/phone such as Iris or f.lux.
Stop drinking caffeine or stimulants by 2 PM. Even folks who “sleep fine” drinking caffeine after this, it has been shown to decrease the REM and deep stages of sleep regardless.
Keep your room and bed cool. The optimal ambient temperature for sleep is around 68 degrees.
Black your room out as much as possible. Even small lights such as a tiny indicator light on a TV has been shown to disrupt sleep
Use magnesium before bed. Magnesium is a central nervous system relaxant and magnesium deficiency is very common. Citrate and glycinate are good supplemental forms – 200 – 400mg, up to 600mg to be taken before bed.
Your bed is for sleeping and that’s it! Don’t do work on your laptop in your bed. Don’t watch TV in your bed. Etcetera. If you’re used to doing these things, your brain associates bed with work or bed with blue light and mental stimulation. This can cause insomnia.
Be active and exercise during the day, but not too close to sleep. Higher amounts of energy expenditure during the day has been shown to aid in sleep quantity and quality at night.
Stop eating at least 3 hours before bed. If you eat too close to bed, your body is working to digest, which has been shown to cause night wake-ups and decrease both REM and deep sleep.
Don’t drink alcohol before bed. Even as much as one glass of wine or beer has been shown to disrupt sleep quality and length, causing more night wakeups.
Certain supplements may help: Valerian root extract, chamomile extract, glycine powder, PharmaGaba, melatonin.
Chronic stress, as noted in the first part of this post, both physical and mental, is a huge detriment to many aspects of health. Chronic stress causes a chronic low grade elevation of cortisol, causing a chronic suppressing of the immune system.
However, it is important to note the concepts of objective stress and subjective stress.
An objective stressor is something that would normally cause stress. E.g. a car accident, loss of job or family member, divorce, etc.
Subjective stress is how you actually perceive the stress and if you actually feel stress from it. Some individuals feel immense stress from a small stressor, such as running out of toothpaste. Whereas other individuals may not feel a whole lot of stress from a large
objective stressor such as a car accident.
What actually matters in terms of raising cortisol and suppressing the immune system is subjective stress. Therefor, there are actions you can take to decrease your subjective stress and therefor prevent suppression of your immune system.
Sleep 8 hours a night
Sleep obviously directly impacts immunity like I talked about in the first part, but it also impacts your ability to handle stress.
Sleep deprivation has been shown to elevate the fight or flight response, translating to an increase in subjective stress to smaller objective stressors.
I’m sure we’ve all experienced differences in our abilities to handle stress – sometimes it seems like the world is ending when we’re missing an ingredient to make a recipe. But other times you’ll get in a fender-bender and shrug your shoulders. Sleep can make all the difference in this.
Although it may sound woo-woo, meditation has tons and tons of clinical research backing its efficacy for stress relief and health.
Getting proficient at meditation is hard. It’s as much of a skill as learning to ride a bike or learning to ski or snowboard. When you first start out, you’ll probably be anxious and questioning why you’re doing it and not feeling much. Stick with it. Start with 5 minutes a day and escalate from there.
If you’re new to meditation, download an app to begin will help. There are lots out there, but I personally like the Waking Up app by Sam Harris.
Another seemingly woo-woo practice, but focusing on the breath with different practices has been shown to decrease cortisol and bring you back to baseline.
Box breathing has been shown efficacious for this: Inhale to a 4 count, hold at the top for a 4 count, exhale for a 4 count, hold at the bottom for a 4 count and repeat.
Alternate nostril breathing is also effective for this. Sit up long and straight, cover the right nostril, and inhale with a deep breath. At the top, uncover the right and cover the left nostril to exhale. Repeat.
Get more sunlight
Sunlight effects your immunity in various different ways from indirect to direct.
Sunlight boosts immunity indirectly by boosting vitamin D production. Since I went in depth in the food/supplement section, I don’t need to be redundant here.
Directly Boosts Immunity via T-cells
Sunlight has been shown to literally speed up T-cells so that they can do their bacteria and virus-fighting job faster.
Another indirect mechanism tying it together, more sun exposure during the day improves sleep quality and duration at night, which has numerous effects in supporting immunity.
The aforementioned effects occur when certain rays of the sun are the strongest – Generally from 9 AM to 2 PM. A good practice would be to try to spend 40 – 60 minutes outside during this time with as much skin exposed as possible. However, some is better than none. If you can only get ten minutes, go for it.
Summary, Takeaways, and Recommended Protocol
On the lifestyle side, be active during the day and exercise, sleep 8 hours a night, get as much sun as you can, and practice stress mitigation techniques such as meditation and breathwork.
On the food side, make your diet as varied as possible – include various sources of meat and animal products to ensure your intakes of vitamin A, zinc, and other important micronutrients are adequate. Include as many different plants as possible as well.
On the supplement side, if you’re limited by budget (and most of us are), then I would do the following.
If you can only afford one thing, vitamin D is a must. Vitamin D deficiency is rampant in the modern age with everyone sitting inside having 9 to 5’s.
I saw this first hand working in a doctors office for over a year. Witnessing the bloodwork of patient after patient; it was actually very rare that someone had even an adequate level of vitamin D, let alone an optimized level.
A good supplemental dose is 2000 IU/day in general and up to 4000 IU/day during winter. Of course, the best way to assess is to actually get your 25-OH-D tested and supplement accordingly.
Other order of operations –
I would go with supplemental zinc using the Jarrow Zinc Balance, and keeping Life Extension Zinc Acetate Lozenges on hand if you start to feel a scratchy throat.
Keep Vitamin C on hand at 1000mg per cap or pressed pill. During cold or flu season, I would take at least 2000mg/day, but if you’re starting to feel under the weather, doing 3-4 2000mg doses per day can work well. However, take note that some people have a lower gastric tolerance for vitamin C and larger doses can cause stomach upset. I’ve not experienced any stomach upset from the doses I mentioned.
These are the strongly recommended supplements. If you want to experiment more, take 2 or 3 from the list and try them. Ones Ive tried with success are Reishi extract, Astragalus, and Elderberry extract.
Hope all this helps. Stay safe and healthy.
2. Low-Grade Inflammation Is Associated with Susceptibility to Infection in Healthy Men: Results from the Danish Blood Donor Study (DBDS)Kathrine Agergård Kaspersen, Khoa Manh Dinh, Lise Tornvig Erikstrup, Kristoffer Sølvsten Burgdorf, Ole Birger Pedersen, Erik Sørensen, Mikkel Steen Petersen, Henrik Hjalgrim, Klaus Rostgaard, Kaspar Rene Nielsen, Henrik Ullum, Christian Erikstrup PLoS One. 2016; 11(10): e0164220. Published online 2016 Oct 4. doi: 10.1371/journal.pone.0164220
6. Zwickey, H., Brush, J., Iacullo, C.M., Connelly, E., Gregory, W.L., Soumyanath, A. and Buresh, R. (2007), The effect of Echinacea purpurea, Astragalus membranaceus and Glycyrrhiza glabra on CD25 expression in humans: a pilot study. Phytother. Res., 21: 1109-1112. doi:10.1002/ptr.2207
7. Aranow, Cynthia. “Vitamin D and the immune system.” Journal of investigative medicine : the official publication of the American Federation for Clinical Research vol. 59,6 (2011): 881-6. doi:10.2310/JIM.0b013e31821b8755
9. Otsuki T, Shimizu K, Iemitsu M, Kono I. Salivary secretory immunoglobulin A secretion increases after 4-weeks ingestion of chlorella-derived multicomponent supplement in humans: a randomized cross over study. Nutr J. 2011;10:91. Published 2011 Sep 9. doi:10.1186/1475-2891-10-91
11. Zhao, R., Chen, Q. & He, Y. The effect of Ganoderma lucidum extract on immunological function and identify its anti-tumor immunostimulatory activity based on the biological network. Sci Rep 8, 12680 (2018). https://doi.org/10.1038/s41598-018-30881-0
12. Mondal S, Varma S, Bamola VD, et al. Double-blinded randomized controlled trial for immunomodulatory effects of Tulsi (Ocimum sanctum Linn.) leaf extract on healthy volunteers. J Ethnopharmacol. 2011;136(3):452–456. doi:10.1016/j.jep.2011.05.012
13. Işik H, Cevikbaş A, Gürer US, et al. Potential adjuvant effects of Nigella sativa seeds to improve specific immunotherapy in allergic rhinitis patients. Med Princ Pract. 2010;19(3):206–211. doi:10.1159/000285289
17. Arranz L, Fernández C, Rodríguez A, Ribera JM, De la Fuente M. The glutathione precursor N-acetylcysteine improves immune function in postmenopausal women. Free Radic Biol Med. 2008;45(9):1252–1262. doi:10.1016/j.freeradbiomed.2008.07.014
18. Golnoosh Torabian, Peter Valtchev, Qayyum Adil, Fariba Dehghani. Anti-influenza activity of elderberry (Sambucus nigra),
Journal of Functional Foods, Volume 54, 2019, Pages 353-360, ISSN 1756-4646, https://doi.org/10.1016/j.jff.2019.01.031.