How chiropractors may influence immunity: Zinc supplementation

In chiropractic circles, it is commonly said that subluxations are caused by trauma, toxins and stress. In turn, these subluxations, which ASRF defines as ”a diminished state of being, comprising a state of reduced coherence, altered biomechanical function, altered neurological function and altered adaptability” can manifest increased inflammation.

Why? A system that cannot adapt to its environment is at its mercy – whether it be colds, flus, inflammation, or reduced range of motion.

So what does all this have to do with zinc supplementation? While evidence for chiropractic support of immune function is still emerging, and the parameters of what we can and can’t claim are still being drawn, there is one thing that is a little simpler to answer. That is whether or not it might be beneficial for zinc supplementation to be a weapon in the chiropractic artillery. A recent review published in the Asia-Pacific Journal of Chiropractic brings to light the importance of zinc and the role it can play in immune function (1). For us to properly understand how zinc and its effects fit into the chiropractic context, we need to take a step back and first look at what a lack of zinc, or a zinc deficiency, can cause.

Background:

Vitamin and mineral deficiencies, and zinc specifically, can contribute to a wide array of illnesses. Even in the beginning of life, zinc has an important role to play in supporting strong health in both mother and baby. Maternal zinc deficiency has been associated with epigenetic modifications in babies, which can increase the risk of developing diseases later in life (2).

If you are unfamiliar with epigenetics, it may be helpful to think of it as the step beyond changes to the DNA sequence. Epigenetic modifications can be inherited and alter the way DNA is expressed, and therefore how active or inactive different genes are. These modifications can have little obvious impact or can appear as significant changes to expected levels of various proteins, and even change how a system functions. In essence, zinc deficiency during pregnancy can predispose the body to illness later in life, even before exposure to internal and external stressors.

Looking into that later life, zinc deficiency in adulthood can contribute to another lot of issues and potential illnesses. Zinc is a key player in the functioning of various enzymes and biological processes, and thus a lack of zinc can affect many different aspects of the body.

Zinc deficiency has been associated with anxiety and psychological stress, with some studies beginning to consider whether nutrient supplementation can minimise these effects (3-5).

When considering central nervous system health, a core element of chiropractic, Zinc supplementation has been proposed as a useful treatment in spinal cord injury. One such study found that increasing zinc concentrations in the spinal cord was correlated with increasing levels of brain-derived neurotrophic factor (BDNF) (6). BDNF is a protein that promotes the survival, growth, and maturation of neurons, which is particularly vital when trying to support spinal cord repair. That being said, the study does mention that exposure to excess zinc is known to be a risk factor in neuron death in brain and spinal cord injuries, so it is important that the right amount of zinc is supplemented in these injuries. A similar study found that zinc can improve functional recovery by regulating/increasing the secretion of factors that modulate inflammation and reduce neuronal apoptosis at the injury site (7).

A detailed overview of the relationship between zinc and the central nervous system can be found at the reference below (8). It touches on the role zinc plays in gene expression regulation and various enzyme activity. It also delves into the effects of zinc in neurogenesis, development, synaptic activity, and interestingly neuronal plasticity.

Neuronal plasticity, or neuroplasticity, is a hot topic in the world of brain science, and is likely to stay that way for a while. And as traditional science and medicine finds its own way through this juggernaut of possibilities, we are already seeing indications that chiropractic care changes the structure and function of the brain. (20) So, to drop the proverbial breadcrumbs as closely together as we can – it stands to reason that zinc supplementation may be advantageous for individuals under chiropractic care.

While there are many other studies, and we cannot cover them all in one go (you wouldn’t want us to – I promise), other research has highlighted zinc deficiency affecting vascular function. Specifically in angiogenesis in the context of stroke recovery, and the development and perpetuation of pressure ulcers (9,10).

 

The Current Paper

Now that we are informed of the importance of zinc across various areas of physical and psychological health, we can return to the paper recently published in the APCJ. The paper covered ‘defensive health’, a phrase used to describe the topic of immunity and what this means for chiropractors. More specifically, this article looked at zinc, how it affects general immune function, viral immunity, and what implications this has for chiropractic.

The article summarised 6 papers, including literature and systematic reviews, that describe the current literature regarding zinc and the role it plays in immune function (11-16). The important takeaways from the paper include:

• Serum and plasma zinc levels of samples from autoimmune disease patients are significantly lower than in controls which supports a relationship between zinc intake and immune function
• Zinc has been used as a therapeutic for viral infections such as herpes simplex virus and the common cold.
• A small number of studies suggest zinc may improve antibody titres and antibacterial responses to pneumococcal and cholera infections
• Zinc deficiency affects cells involved in both the adaptive and innate immune system at the survival, proliferation, and maturation levels.
• The balance between the different T helper cell subset are particularly susceptible to change in zinc levels (T helper cells are important ‘bridges’ from innate immune response to adaptive immune response. Adaptive immunity is the bigger and better one, it is responsible for generating a specific immune response, and also responsible for developing memory cells which is how we generate ‘immunity’ to different pathogens so you want to make sure the adaptive immune system is getting activated in the right way at the right time).
• Zinc deficiencies and zinc excess can result in severe disturbances in immune cell numbers, and subsequently immune activity. This can lead to increased susceptibility to infections and development of especially inflammatory diseases.
• For intracellular signalling pathways; the main underlying molecular mechanisms and targets affected by altered zinc homeostasis included kinases, caspases, phosphatases, and phosphodiesterases.
• Sublingual zinc (under the tongue) did not prevent clinical colds from developing following viral exposure, but they did find there were clinically significant reductions in day 4 symptom severity, but not average daily symptom severity
• No significant aftereffects were reported in the 25 RCTs that monitored them (Hunter et al)
• The paper also mentions that a Zinc taste test is not a bad option for gauging zinc levels/deficiency

What does this mean for chiropractic?

In light of all of this information, it seems logical that Chiropractors consider promoting adequate zinc intake to all patients. But if you are still unconvinced of the relevancy of zinc deficiency to individuals presenting at chiropractic clinics; here is even more research.

An aspect that has been briefly mentioned is the relationship between zinc deficiency and inflammation. We know that inflammation is an important aspect of many pathologies, and can even drive the development of subluxations. This can form a kind of loop in which inflammation is contributing to nervous system dysfunction, which in turn is allowing further inflammation.

Zinc is involved in modulating the proinflammatory response, and thus a lack of zinc can contribute to an increase in inflammation.

• Zinc deficiency results in immune dysfunction and promotes systemic inflammation (17)
• Zinc deficiency has also been associated with the promotion of carcinogenesis (via inflammation as one pathway) and tumorigenesis (18)
• Zinc deficiency can also lead to impaired immune function. (19)

As noted by the study’s author, “It would seem that the most prudent action remains for a chiropractors to inform their patients of up-to-date findings such as reported in this paper, and allow them to make their own decisions.”

A combination of well-adjusted and well-informed? We like that!

 

References:

1. Ebrall P. How chiropractors may influence immunity: Zinc supplementation. A speed update of the literature. Asia-Pac Chiropr J. 2022;2.4. URL apcj.net/papers-issue-2-5/#Ebrallimmunity
2. Sanusi KO, Ibrahim KG, Abubakar B, Malami I, Bello MB, Imam MU, et al. Effect of maternal zinc deficiency on offspring health: The epigenetic impact. Journal of Trace Elements in Medicine and Biology. 2021. 65:126731.
3. Russo AJ. Decreased zinc and increased copper in individuals with anxiety. Nutr Metab Insights. 2011. 4:1-5. doi:10.4137/NMI.S6349
4. Tao L, Zheng Y, Shen Z, Shen H. Psychological Stress-Induced Lower Serum Zinc and Zinc Redistribution in Rats. Biological Trace Element Research. 2013. 155(1).
5. Kaplan BJ, Rucklidge JJ, Romijn AR, Dolph M. A randomised trial of nutrient supplements to minimise psychological stress after a natural disaster. Psychiatry Research. 2015. 228(3):373–9.
6. Wang Y, Me X, Zhang L, Lv G. Supplement moderate zinc as an effective treatment for spinal cord injury. Medical Hypotheses. 2011. 77(4):589–90. Available from: https://pubmed.ncbi.nlm.nih.gov/21752551/
7. Li X, Chen S, Mao L, Li D, Xu C, Tian H, et al. Zinc Improves Functional Recovery by Regulating the Secretion of Granulocyte Colony Stimulating Factor From Microglia/Macrophages After Spinal Cord Injury. Frontiers in Molecular Neuroscience. 2019. 12.
8. Gower-Winter SD, Levenson CW. Zinc in the central nervous system: From molecules to behavior. BioFactors. 2012. 38(3):186–93.
9. Tsuruoka T, Kodama A, Yamaguchi S, Masutomi T, Koyama A, Murohara T, et al. Zinc deficiency impairs ischemia-induced angiogenesis. JVS: Vascular Science. 2022. 3:30–40.
10. Nakamura H, Sekiguchi A, Ogawa Y, Kawamura T, Akai R, Iwawaki T, et al. Zinc deficiency exacerbates pressure ulcers by increasing oxidative stress and ATP in the skin. Journal of Dermatological Science. 2019. 95(2):62–9.
11. Sanna A, Firinu D, Zavattari P, Valera P. Zinc Status and Autoimmunity: A Systematic Review and Meta-Analysis. Nutrients. 2018. 10(1):68. DOI 10.3390/nu10010068. PMID: 29324654
12. Read SA, Obeid S, Ahlenstiel C, Ahlenstiel G. The Role of Zinc in Antiviral Immunity. Adv Nutr. 2019. 10(4):696-710. DOI 10.1093/advances/nmz013. PMID: 31305906
13. Bonaventura P, Benedetti G, Albarède F, Miossec P. Zinc and its role in immunity and inflammation. Autoimmun Rev. 2015. 14(4):277-85. DOI 10.1016/j.autrev.2014.11.008. Epub 2014 Nov 24. PMID: 25462582
14. Maywald M, Wessels I, Rink L. Zinc Signals and Immunity. Int J Mol Sci. 2017. 18(10):2222. DOI 10.3390/ijms18102222. PMID: 29064429
15. Maares M, Haase H. Zinc and immunity: An essential interrelation. Arch Biochem Biophys. 2016 Dec 1;611:58-65. doi: 10.1016/j.abb.2016.03.022. Epub 2016 Mar 26. PMID: 27021581
16. Hunter J, Arentz S, Goldenberg J, et al Zinc for the prevention or treatment of acute viral respiratory tract infections in adults: a rapid systematic review and meta-analysis of randomised controlled trials BMJ Open 2021;11:e047474. DOI 10.1136/bmjopen-2020-047474
17. Wong CP, Rinaldi NA, Ho E. Zinc deficiency enhanced inflammatory response by increasing immune cell activation and inducing IL6 promoter demethylation. Molecular Nutrition & Food Research. 2015. 59(5):991–9.
18. Zhang Y, Tian Y, Zhang H, Xu B, Chen H. Potential pathways of zinc deficiency-promoted tumorigenesis. Biomedicine & Pharmacotherapy. 2021. 133:110983.
19. ‌Kloubert V, Wessels I, Wolf J, Blaabjerg K, Janssens V, Hapala J, et al. Zinc deficiency leads to reduced interleukin-2 production by active gene silencing due to enhanced CREMα expression in T cells. Clinical Nutrition. 2021. 40(5):3263–78.
20. Lelic, D, Niazi, IK, Holt, K, Jochumsen, M, Dremstrup, K, Yielder, P, Murphy, B, Drewes, A and Haavik, H (2016), “Manipulation of dysfunctional spinal joints affects sensorimotor integration in the pre-frontal cortex: A brain source localization study,” Neural Plasticity, Volume 2016 (2016).