Whether or not we contract a virus, bacteria, or other pathogen depends on our individual susceptibility. So what makes someone more susceptible to becoming ill? Some people can have genetically healthier immune systems or better control over their inflammatory responses. However, studies show that external factors impact immunity more than genetics does.1 For example, environmental toxin exposure, psychological stress, obesity, lack of restorative sleep, and dietary intake of nutrients all can keep your immune system from functioning at its best.2 All of these factors cause what’s called allostatic overload.2 Allostatic load refers to the ways in which your body remains in balance. Anything that overtaxes your allostatic load can throw you and your immune system out of balance.
The good news? There are certain ways to improve your immune system naturally. Here are some easy suggestions on how to support immunity. These are especially useful in the winter when we’re confronted by many different immune assaults. However, they can be used all year long with good results. In fact, the lifestyle strategies should be something you do throughout the year to keep you healthy all year long.
The Most Effective Lifestyle Strategies
First, avoid exposure to toxins, which includes pollution. Toxins can reduce immunity and push your body into a hyperinflammatory state.3-6In addition, obesity can lead to weakened lung function, so it’s important to take steps to stay at a healthy weight.7 Getting a good night’s rest is also important. Not getting enough sleep is linked to weakened immune system function and weakened immune cells such as CD4+ and CD8+ T lymphocytes and natural killer cells.8,9
One reason for poor sleep is exposure to light at night, which deprives lots of people of a deep, restful sleep. Exposure to light at night also causes levels of melatonin to drop. Melatonin is an antioxidant and anti-inflammatory that may enhance respiratory health and boost immunity.10,11 Therefore, it’s important to reduce your exposure to light at night.
How To Support Immune System Health
Studies show that a number of botanicals, vitamins, and other nutrients have a role to play in supporting immunity. I always recommend to my patients that they keep these ingredients on hand so they’ll have them when they need them. I like to recommend Tru Immune Support, because it conveniently contains all these effective ingredients in one supplement, along with Tru D3 to make sure your vitamin D3 is at healthy levels.
Astragalus is well known for its ability to provide immune system support. It offers a helping hand to the immune system by improving the function of natural killer cells and reducing activity of proteins known as pro-inflammatory cytokines.12,13 It also enhances the activity of lymphocytes, white blood cells responsible for antibody production.14
Yeast-Based Fermentate (EpiCor®)
EpiCor® is made from a type of yeast (Saccharomyces cerevisiae) that boosts immunity. In preclinical and human studies, EpiCor® improved mucosal immunity, supported the health of people with seasonal allergies, supported a healthy inflammatory response, and helped people under the weather feel better.15-17
Preclinical and cell culture studies show berberine may support immune health. In mice, it supported a healthy inflammatory response in the lungs.18 In both human cells and in mice, berberine blocked viral replication.19,20
Olive Leaf Extract
Olive leaf extract is loaded with polyphenols that keep the immune system and respiratory tract healthy. Olive leaf extract promotes immune health by interacting with the protein of virus particles, weakening virus actions.21 It also stimulates the production of natural killer cells.22 In a randomized, placebo-controlled study of 32 high school athletes, olive leaf extract supported upper respiratory tract health.23 One of the most important components of olive leaf is oleuropein. Tru Immune Support contains olive leaf extract with a generous 16% oleuropein for optimal potency.
Vitamin C and Zinc
These two foundational nutrients are critical for immune health. A meta-analysis of the medical literature found that vitamin C supported the health of 11,077 people who had the common cold.24 Dietary zinc also plays an important role in immunity. Even a mild deficiency of this mineral can weaken the function of immune cells.25 Zinc supplementation can promote immune health in people exposed to wintertime immune system challenges. Researchers have recommended the use of zinc supplements to counteract modern-day immune threats.26 This is because zinc enhances innate and acquired immune responses.26 It can also shield cells from viral entry and replication.26
This herb contains allicin, garlic’s active component that was shown in a human study to keep subjects healthy.27 Even in the subjects that didn’t feel their best, garlic supplementation made them feel better faster. Furthermore, research has shown that garlic essential oil acts on the angiotensin-converting enzyme 2 (ACE2) protein.28 ACE2 is involved in cellular immune defense.28
Citrus bioflavonoids are immune-promoting compounds that come from citrus fruits such as oranges and lemons. In particular, the citrus bioflavonoid hesperidin has immune-boosting abilities.29,30 Citrus bioflavonoids team up with vitamin C to enhance immune health.
N-Acetyl Cysteine (NAC)
This antioxidant has several useful abilities. First, it breaks up mucous and clears the respiratory passages.31 Second, it supports lung health.31 Human research has found NAC can significantly support immune system health and lung function at times when immune support is needed the most. 32
Vitamin D3 is an important player in immune health. A systematic review and meta-analysis of the medical literature including 25 randomized, controlled trials of 11,321 people found that vitamin D supplementation improved respiratory tract health in all the study subjects.33 The beneficial effects were most evident in the people with vitamin D deficiency. Healthy vitamin D levels are also linked to better immune function, reduced levels of inflammatory cytokines, and good respiratory function.34-36
Cannabidiol’s Role in Immune Health
Many people don’t think about Cannabidiol (CBD) in terms of enhancing immunity. However, research is unveiling possible ways CBD may be involved in immune health. CBD works through what’s known as the endocannabinoid system. This system includes receptors like CB1 and CB2 and endocannabinoids that your body produces that work on these receptors. Sometimes, due to factors like psychological stress, people can suffer from endocannabinoid deficiency, where they’re not producing enough endocannabinoids or the system simply doesn’t work the way it should. This can lead to problems in many areas of health, including immunity.37
The evidence that CBD can play a role in keeping the immune system healthy begins with the fact that immune cells express the CB2 receptor and to a lesser extent CB1.38 However, CBD also works through other receptors that are related to the endocannabinoid system, although not directly a part of it. For example, CBD activates transient receptor potential vanilloid 2 (TRPV2), a protein that plays a role in healthy immune system function.39 What’s more, CBD enhances the action of natural killer cells.40
CBD can also soothe the inflammatory response in the gut, where much of the immune system is located.41 In addition, by reducing the production of inflammatory cytokines and promoting a healthy inflammatory response, CBD keeps the lungs and respiratory tract healthy.42-46 Finally, CBD has a calming effect that reduces stress.47 Psychological stress is associated with reduced immunity.48
The Bottom Line on Immune System Support
One of the most important considerations as to whether or not you stay healthy is how susceptible you are. To summarize the points in this article:
- Make sure to regularly get restorative sleep in a dark room.
- Detoxify your body of toxins and avoid toxin exposure in the first place to keep your body from becoming overburdened.
- Take steps to remain at a healthy weight.
- Promote immune system health by using Tru Immune Support, which contains the ingredients mentioned in this article.
- Add Tru D3 into your supplement routine to take advantage of vitamin D3’s ability to support immune health.
- Finally, as an additional way to power up the immune system, add CBD to your supplement routine.
- Brodin P, Jojic V, Gao T, et al. Variation in the human immune system is largely driven by non-heritable influences. Cell. 2015;160(1-2):37-47.
- McEwen B. Stress: Homeostasis, Rheostasis, Reactive Scope, Allostasis and Allostatic Load. https://www.sciencedirect.com/topics/neuroscience/allostatic-load. Accessed October 18, 2020.
- Wang M, Zhao J, Wang Y, et al. Genome-wide DNA methylation analysis reveals significant impact of long-term ambient air pollution exposure on biological functions related to mitochondria and immune response. Environ Pollut. 2020;264:114707.
- Henderson SB. The COVID-19 Pandemic and Wildfire Smoke: Potentially Concomitant Disasters. Am J Public Health. 2020;110(8):1140-1142.
- Deek SA. Chronic exposure to air pollution implications on COVID-19 severity. Med Hypotheses. 2020;145:110303.
- Araiza V, Mendoza MS, Castro KEN, et al. Bisphenol A, an endocrine-disruptor compund, that modulates the immune response to infections. Front Biosci (Landmark Ed). 2021;26:346-362.
- Kimura T, Namkoong H. Susceptibility of obese population to COVID-19. Int J Infect Dis. 2020.
- Ibarra-Coronado EG, Pantaleón-Martínez AM, Velazquéz-Moctezuma J, et al. The Bidirectional Relationship between Sleep and Immunity against Infections. J Immunol Res. 2015;2015:678164.
- Dinarello CA. Overview of the IL-1 family in innate inflammation and acquired immunity. Immunol Rev. 2018;281(1):8-27.
- Huang SH, Cao XJ, Liu W, Shi XY, Wei W. Inhibitory effect of melatonin on lung oxidative stress induced by respiratory syncytial virus infection in mice. J Pineal Res. 2010;48(2):109-116.
- Yip HK, Chang YC, Wallace CG, et al. Melatonin treatment improves adipose-derived mesenchymal stem cell therapy for acute lung ischemia-reperfusion injury. J Pineal Res. 2013;54(2):207-221.
- Jiang D, Wang X, Su Q, et al. Milkvetch root improves immune function in patients with acute exacerbation of COPD. Biomed Mater Eng. 2015;26 Suppl 1:S2113-2121. 13. Huang ZQ, Qin NP, Ye W. [Effect of Astragalus membranaceus on T-lymphocyte subsets in patients with viral myocarditis]. Zhongguo Zhong Xi Yi Jie He Za Zhi. 1995;15(6):328-330.
- Niu GH, Sun X, Zhang CM. [Effect of compound astragalus recipe on lymphocyte subset, immunoglobulin and complements in patients with myasthenia gravia]. Zhongguo Zhong Xi Yi Jie He Za Zhi. 2009;29(4):305-308.
- Moyad MA, Robinson LE, Zawada ET, Jr., et al. Effects of a modified yeast supplement on cold/flu symptoms. Urol Nurs. 2008;28(1):50-55.
- Moyad MA, Robinson LE, Zawada ET, et al. Immunogenic yeast-based fermentate for cold/flu-like symptoms in nonvaccinated individuals. J Altern Complement Med. 2010;16(2):213-218.
- Moyad MA, Robinson LE, Kittelsrud JM, et al. Immunogenic yeast-based fermentation product reduces allergic rhinitis-induced nasal congestion: a randomized, double-blind, placebo-controlled trial. Adv Ther. 2009;26(8):795-804.
- Yan YQ, Fu YJ, Wu S, et al. Anti-influenza activity of berberine improves prognosis by reducing viral replication in mice. Phytother Res. 2018;32(12):2560-2567. 19. Wu Y, Li JQ, Kim YJ, Wu J, Wang Q, Hao Y. In vivo and in vitro antiviral effects of berberine on influenza virus. Chin J Integr Med. 2011;17(6):444-452.
- Botwina P, Owczarek K, Rajfur Z, et al. Berberine Hampers Influenza A Replication through Inhibition of MAPK/ERK Pathway. Viruses. 2020;12(3).
- Lee-Huang S, Zhang L, Huang PL, Chang YT, Huang PL. Anti-HIV activity of olive leaf extract (OLE) and modulation of host cell gene expression by HIV-1 infection and OLE treatment. Biochem Biophys Res Commun. 2003;307(4):1029-1037.
- Magrone T, Spagnoletta A, Salvatore R, et al. Olive Leaf Extracts Act as Modulators of the Human Immune Response. Endocr Metab Immune Disord Drug Targets. 2018;18(1):85-93.
- Somerville V, Moore R, Braakhuis A. The Effect of Olive Leaf Extract on Upper Respiratory Illness in High School Athletes: A Randomised Control Trial. Nutrients. 2019;11(2).
- Douglas RM, Hemila H, D’Souza R, Chalker EB, Treacy B. Vitamin C for preventing and treating the common cold. Cochrane Database Syst Rev. 2004(4):Cd000980. 25. Roxas M, Jurenka J. Colds and influenza: a review of diagnosis and conventional, botanical, and nutritional considerations. Altern Med Rev. 2007;12(1):25-48.
- Ateya AM, Sabri NA. Zinc supplementation for males during COVID-19: Is it beneficial? Med Hypotheses. 2020:110403.
- Josling P. Preventing the common cold with a garlic supplement: a double-blind, placebo-controlled survey. Adv Ther. 2001;18(4):189-193.
- Thuy BTP, My TTA, Hai NTT, et al. Investigation into SARS-CoV-2 Resistance of Compounds in Garlic Essential Oil. ACS Omega. 2020;5(14):8312-8320.
- Saha RK, Takahashi T, Suzuki T. Glucosyl hesperidin prevents influenza a virus replication in vitro by inhibition of viral sialidase. Biol Pharm Bull. 2009;32(7):1188- 1192.
- Kim HK, Jeon WK, Ko BS. Flavanone glycosides from Citrus junos and their anti influenza virus activity. Planta Med. 2001;67(6):548-549.
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- Martineau AR, Jolliffe DA, Hooper RL, et al. Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data. Bmj. 2017;356:i6583.
- Maghbooli Z, Sahraian MA, Ebrahimi M, et al. Vitamin D sufficiency, a serum 25- hydroxyvitamin D at least 30 ng/mL reduced risk for adverse clinical outcomes in patients with COVID-19 infection. PLoS One. 2020;15(9):e0239799.
- Ye K, Tang F, Liao X, et al. Does Serum Vitamin D Level Affect COVID-19 Infection and Its Severity?-A Case-Control Study. J Am Coll Nutr. 2020:1-8.
- Musavi H, Abazari O, Barartabar Z, et al. The benefits of Vitamin D in the COVID-19 pandemic: biochemical and immunological mechanisms. Arch Physiol Biochem. 2020:1- 9.
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