5 Supplements that Boost Your Immune Function

Jan 11, 2024 | Written by Matthew Lees, PhD and Marion Hall | Reviewed by Scott Sherr, MD and Marion Hall

5 Supplements that Boost Your Immune Function

The immune system is a vitally important network that integrates organs, cells, and proteins throughout the body to fight infection and protect cells from abnormal changes. Without it, we would have no way to protect ourselves from harmful things that enter the body, such as disease-causing germs or pathogens (bacteria, fungi, viruses, or parasites). In this role, the immune system has two arms, referred to as the innate and adaptive systems [1,2].

The innate system defends against foreign bodies, injuries, and pathogens, and is a faster albeit more general line of defense. The adaptive system is slower to engage but is geared towards specific pathogens or altered cells within the body.

The immune system does far more than simply fight infection. It also recognizes and neutralizes harmful substances we might encounter in the environment. It also detects abnormal cells, such as those associated with cancer, that can lead to disease and death.

When the immune system is operating normally, we are completely unaware, but when problems arise or it isn’t functioning as well as it should, we tend to get sick. Germs that the body hasn’t encountered before are likely to make us ill.

In today’s article, we will take a look at five supplements (and a bonus!) that can support and enhance the immune system to work more optimally to maximize health and well-being.

1. Zinc

Zinc is a well-known mineral and micronutrient that has a significant role in the healthy function and regulation of the immune system [3]. It is an essential trace mineral for all organisms and has been referred to as “the gatekeeper of immune function” [4], so it is fitting that we address it first in this article.

Zinc deficiency is associated with imbalanced immune reactions that favor allergies and autoimmune diseases. In its severe form, zinc deficiency manifests with clinical symptoms like lymphopenia (insufficient white blood cells, or lymphocytes), decreased ratios of T helper cells to cytotoxic T cells, decreased natural killer cell activity, and increased monocyte cytotoxicity.

Supplementation with zinc, under the supervision of a physician, can be a helpful strategy, especially in older people, to ensure that these elements of the immune system remain in optimal function. Careful attention must be paid to the dose, timing, length of treatment, and form of zinc consumed [5].

2. Cordycepin

Cordycepin is a derivative of the nucleoside adenosine, that was initially extracted from the Cordyceps militaris fungus but can now be produced synthetically [6]. It can also be obtained from other fungi within the Cordyceps genus. These fungi have received attention in recent decades due to their immunostimulatory potential [7].

The Cordyceps species, its extracts, and bioactive constituents have been linked with cytokine production, the cellular signaling proteins of the immune system that play a major role in inflammatory and immune responses [8].

Early research has shown promise for Cordyceps in promoting animal survival against influenza by boosting the immune system, whilst also demonstrating anti-inflammatory effects [9]. More recently, work has shown that 500 mg of cordyceps consumed as a food supplement three times a day showed effectiveness in patients with mild to moderate COVID-19 infection [10].

3. Omega-3 Polyunsaturated Fatty Acids

Omega-3 polyunsaturated fatty acids are major components of cell membranes that must be consumed in the diet (i.e., essential fatty acids). Adequate availability of omega-3s supports the integrity and strength of cell membranes throughout the body, including that of immune cells.

In recent years, research has found that omega-3s don’t just help with suppressing inflammation, they also enhance the effectiveness and function of B cells (cells that produce antibodies against pathogens) [11].

Research on omega-3 supplements has indicated that the supplement formulation should be obtained from a certified sustainable source, free from heavy metals and organic pollutants, with minimal processing, and composed of the natural triglyceride form of the fatty acids for improved safety and effectiveness in providing optimal immune support [12].

4. Vitamin C

An essential vitamin and micronutrient, vitamin C is a powerful antioxidant and cofactor for a plethora of biosynthetic and gene-regulatory enzymes [13]. It supports epithelial barrier function against pathogens (the mucus membranes of the mouth and nose for example) and also accumulates in phagocytic cells such as neutrophils that are involved in the process of destroying invading pathogens as a first line of defense. Vitamin C is also needed for the clearance of spent neutrophils from the site of infection by macrophages, reducing tissue damage and necrosis.

Vitamin C deficiency is associated with impaired immunity and higher susceptibility to infections. Supplementation with this important vitamin appears to be able to prevent and treat respiratory and systematic infections [13]. To optimize the cell and tissue levels of vitamin C as a prophylactic against infection, 100-200 mg/day is advised as an initial dietary intake. The treatment of an established infection requires higher amounts due to the increased inflammatory response and metabolic demand [13].

Research studies suggest that adequate intakes of vitamin C and zinc (see above) ameliorate symptoms and shorten the duration of respiratory tract infections like the common cold. Furthermore, vitamin C and zinc reduce the incidence and improve the outcome of pneumonia, malaria, and diarrhea infections, especially in children in developing countries [14].

5. Vitamin D

Although its reputation as the “sunshine vitamin” is well established, alongside its roles in calcium and bone homeostasis [15], vitamin D is also important for immune function.

The vitamin D receptor is expressed on immune cells (i.e., T cells, B cells, and antigen-presenting cells) and vitamin D itself can modulate innate and adaptive immune responses.

Vitamin D deficiency can bring about an increased risk of infection and increased autoimmunity. It is associated with conditions such as psoriasis, type 1 diabetes, multiple sclerosis, and autoimmune diseases.

The current recommendation is to increase vitamin D intake and get sufficient sunlight exposure for a serum vitamin D level of 30 ng/mL (75 nmol/L) and better at 40-60 ng/mL (100-150 nmol/L) to obtain optimal health benefits [16].

Bonus: GABA supplements

Gamma-aminobutyric acid (GABA) is one of the most important inhibitory neurotransmitters in our brain. GABAergic function refers to the relaxation effects that occur through GABA and its receptors in the brain.

While studies have shown that increasing GABA production or intake may improve sleep quality, decrease anxiety, have neuroprotective effects, suppress neurodegeneration, and decrease blood pressure [17,18], it is also known to enhance immune system function.

GABA has various effects on immune cells, such as activation or suppression of cytokine secretion, cell proliferation modification, and cell migration [19]. It also plays a role in autoimmune diseases like multiple sclerosis, type 1 diabetes, and rheumatoid arthritis, as well as modulating the immune response to infections [19]. In an animal model for multiple sclerosis, increasing GABAergic activity ameliorated ongoing paralysis in experimental autoimmune encephalomyelitis via inhibition of inflammation [20].

Given all this information, you must be wondering how to increase your GABA intake! Considering the name of this section, you think we're probably going to suggest GABA supplements. (If you want to learn about other methods to increase GABA in your brain, you can read our list here!)

However, while several drugs can mimic or increase GABA in the brain, such as benzodiazepines and gabapentin, very few supplements are capable of the same thing. This is because exogenous GABA taken as a supplement has very poor bioavailability and cannot penetrate the blood-brain barrier (BBB) on its own [21]. It is glutamate, with the help of vitamin B6, that can cross the BBB to later be converted into GABA. You can learn more about this process in our GABA guide.

But fear not, there are still ways to help GABA get to your brain and to help modulate your GABA system without using drugs, some of which can be found below:

  • Niacin bound to GABA forms N-nicotinoyl-GABA, which helps GABA cross the BBB by increasing both vitamin B3 and GABA levels in the brain.
  • Kava (Piper methysticum) increases the binding of GABA, though the full mechanism has not yet been established [22].
  • Honokiol interacts with GABA receptors in the brain, enhancing their response to GABA and increasing GABAergic neurotransmission.
  • Agarin binds to and activates GABA receptors in the brain, increasing GABA neurotransmission.
  • Cannabidiol (CBD) modulates brain excitatory glutamate and inhibitory GABA levels, and has been found to increase GABA levels and modulate glutamate-GABA systems, though further research is still needed [23].
  • Cannabinol (CBN) indirectly modulates the GABA system and is found to be more effective when used with CBD [24].

Here at Troscriptions, Tro Calm and Tro Zzz are our precision-dosed, pharmaceutical-grade, and physician-formulated buccal troches with ingredients that directly or indirectly modulate the brain's GABAergic system.

Tro Calm is our relaxation troche that will help you take the edge off, chill out, and quiet your mind. It has N-nicotinoyl-GABA, kava, and CBD among its ingredients.

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Pick out and try the product that suits your needs for a GABA boost!


In this article, we looked at five different supplements and their roles in enhancing immune function. We explored the impact of zinc, the important antioxidant vitamin C, the fat-soluble vitamin D, omega-3 fatty acids, and cordycepin. We also discussed how increasing GABA production or intake can boost your immune function, and provided some non-drug ways to do so.

If you’re planning on taking any new supplementation, make sure to consult with a medical professional before doing so.

You can also try our new product Tro Mune, a health optimization troche for immune support that will swap your endless colds and constant inflammation for an immune shield of unmatched power and resilience!



  1. S. Hillion, M.I. Arleevskaya, P. Blanco, A. Bordron, W.H. Brooks, J.Y. Cesbron, S. Kaveri, E. Vivier, Y. Renaudineau, The Innate Part of the Adaptive Immune System, Clin Rev Allergy Immunol 58 (2020) 151–154. https://doi.org/10.1007/s12016-019-08740-1.
  2. D.D. Chaplin, Overview of the immune response, J Allergy Clin Immunol 125 (2010) S3-23. https://doi.org/10.1016/j.jaci.2009.12.980.
  3. A.S. Prasad, Zinc in human health: effect of zinc on immune cells, Mol Med 14 (2008) 353–357. https://doi.org/10.2119/2008-00033.Prasad.
  4. I. Wessels, M. Maywald, L. Rink, Zinc as a Gatekeeper of Immune Function, Nutrients 9 (2017) 1286. https://doi.org/10.3390/nu9121286.
  5. E. Mocchegiani, J. Romeo, M. Malavolta, L. Costarelli, R. Giacconi, L.-E. Diaz, A. Marcos, Zinc: dietary intake and impact of supplementation on immune function in elderly, Age (Dordr) 35 (2013) 839–860. https://doi.org/10.1007/s11357-011-9377-3.
  6. S. Huang, H. Liu, Y. Sun, J. Chen, X. Li, J. Xu, Y. Hu, Y. Li, Z. Deng, S. Zhong, An effective and convenient synthesis of cordycepin from adenosine, Chem. Pap. 72 (2018) 149–160. https://doi.org/10.1007/s11696-017-0266-9.
  7. G. Das, H.-S. Shin, G. Leyva-Gómez, M.L.D. Prado-Audelo, H. Cortes, Y.D. Singh, M.K. Panda, A.P. Mishra, M. Nigam, S. Saklani, P.K. Chaturi, M. Martorell, N. Cruz-Martins, V. Sharma, N. Garg, R. Sharma, J.K. Patra, Cordyceps spp.: A Review on Its Immune-Stimulatory and Other Biological Potentials, Front Pharmacol 11 (2020) 602364. https://doi.org/10.3389/fphar.2020.602364.
  8. J.-M. Zhang, J. An, Cytokines, inflammation, and pain, Int Anesthesiol Clin 45 (2007) 27–37. https://doi.org/10.1097/AIA.0b013e318034194e.
  9. Y. Park, S. Choi, B. Kim, S.G. Lee, Effects of Cordyceps militaris Extracts on Macrophage as Immune Conductors, Applied Sciences 11 (2021) 2206. https://doi.org/10.3390/app11052206.
  10. S. Dubhashi, S. Sinha, S. Dwivedi, J. Ghanekar, S. Kadam, P. Samant, V. Datta, S. Singh, I.H. Chaudry, P. Gurmet, H. Kelkar, R. Mishra, S. Galwankar, A. Agrawal, Early Trends to Show the Efficacy of Cordyceps militaris in Mild to Moderate COVID Inflammation, Cureus 15 (2023) e43731. https://doi.org/10.7759/cureus.43731.
  11. E.A. Gurzell, H. Teague, M. Harris, J. Clinthorne, S.R. Shaikh, J.I. Fenton, DHA-enriched fish oil targets B cell lipid microdomains and enhances ex vivo and in vivo B cell function, Journal of Leukocyte Biology 93 (2013) 463–470. https://doi.org/10.1189/jlb.0812394.
  12. J.S. Bland, Therapeutic Use of Omega-3 Fatty Acids for Immune Disorders In Search of the Ideal Omega-3 Supplement, Integr Med (Encinitas) 21 (2022) 14–18.
  13. A.C. Carr, S. Maggini, Vitamin C and Immune Function, Nutrients 9 (2017) 1211. https://doi.org/10.3390/nu9111211.
  14. E.S. Wintergerst, S. Maggini, D.H. Hornig, Immune-enhancing role of vitamin C and zinc and effect on clinical conditions, Ann Nutr Metab 50 (2006) 85–94. https://doi.org/10.1159/000090495.
  15. C. Aranow, Vitamin D and the immune system, J Investig Med 59 (2011) 881–886. https://doi.org/10.2310/JIM.0b013e31821b8755.
  16. C. Sîrbe, S. Rednic, A. Grama, T.L. Pop, An Update on the Effects of Vitamin D on the Immune System and Autoimmune Diseases, IJMS 23 (2022) 9784. https://doi.org/10.3390/ijms23179784.
  17. P. Hepsomali, J.A. Groeger, J. Nishihira, A. Scholey, Effects of Oral Gamma-Aminobutyric Acid (GABA) Administration on Stress and Sleep in Humans: A Systematic Review, Frontiers in neuroscience 14 (2020) 923. https://doi.org/10.3389/fnins.2020.00923
  18. D.H. Ngo, T.S. Vo, An Updated Review on Pharmaceutical Properties of Gamma-Aminobutyric Acid, Molecules (Basel, Switzerland) 24 (2019) 2678. https://doi.org/10.3390/molecules24152678
  19. Z. Jin, S.K. Mendu, B. Birnir, GABA is an effective immunomodulatory molecule, Amino acids 45 (2013) 87–94. https://doi.org/10.1007/s00726-011-1193-7
  20. R. Bhat, R. Axtell, A. Mitra, M. Miranda, C. Lock, R.W. Tsien, L. Steinman, Inhibitory role for GABA in autoimmune inflammation, Proceedings of the National Academy of Sciences 107 (2010) 2580-2585. https://doi.org/10.1073/pnas.0915139107
  21. J.I. Byun, Y.Y. Shin, S.E. Chung, W.C. Shin, Safety and Efficacy of Gamma-Aminobutyric Acid from Fermented Rice Germ in Patients with Insomnia Symptoms: A Randomized, Double-Blind Trial, Journal of clinical neurology (Seoul, Korea) 14 (2018) 291–295. https://doi.org/10.3988/jcn.2018.14.3.291
  22. A. Jussofie, A. Schmiz, C. Hiemke, Kavapyrone enriched extract from Piper methysticum as modulator of the GABA binding site in different regions of rat brain, Psychopharmacology 116 (1994) 469-474. https://doi.org/10.1007/BF02247480.
  23. C.M. Pretzsch, J. Freyberg, B. Voinescu, D. Lythgoe, J. Horder, M.A. Mendez, R. Wichers, L. Ajram, G. Ivin, M. Heasman, R.A.E. Edden, S. Williams, D.G.M. Murphy, E. Daly, G.M. McAlonan, Effects of cannabidiol on brain excitation and inhibition systems; a randomised placebo-controlled single dose trial during magnetic resonance spectroscopy in adults with and without autism spectrum disorder, Neuropsychopharmacology 44 (2019) 1398–405. https://doi.org/10.1038/s41386-019-0333-8.
  24. C. Maioli, D. Mattoteia, H.I. Amin, A. Minassi, D. Caprioglio, Cannabinol: History,  syntheses, and biological profile of the greatest “Minor” cannabinoid, Plants 11 (2022) 2896.  https://doi.org/10.3390/plants11212896

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