Immune System Basics and How To Strengthen It for Good Health
Written by Dr Miriam Mikicki, in Jan 2021
In today’s world, we are hearing more and more about our immune system, in particular, with regard to the current pandemic. The immune system, and immunology in general, is a very complicated topic, one that I certainly tried to run away from as a medical student! However, I think it is important to understand the basics of the immune system and the importance of keeping it in balance. We want it to help protect against pathogens but not be too reactive, which can lead to excess inflammation and potential autoimmune issues.
“Immunology Basics- The Innate and Adaptive Immune System”
How do we define the immune system? It can be divided into two parts: innate and adaptive. Our innate system is our first response to any pathogen and is the basic immune system we are born with. It consists of our natural barriers, such as our skin and mucosal linings of our lungs and intestines, alongside certain cell types like macrophages, natural killer cells, and dendritic cells. The natural barriers physically keep pathogens out but also can secrete substances such as mucus and various enzymes that trap or neutralize them.
Cells like macrophages recognize a wide variety of pathogens and create a general response that helps fight oﬀ the start of an infection1. Natural killer cells and macrophages act more locally in the early stages, releasing substances like interferon gamma and TNFa. Often, the innate immune system’s response is enough to kill oﬀ an invading pathogen. However, if it fails to completely stop an infection, it can send signaling molecules called cytokines, which alert and prime our more sophisticated adaptive immune system to launch a more targeted attack2.
Our adaptive immune system consists of more specialized and ‘highly trained’ cells called T and B lymphocytes. These lymphocytes coordinate a more sophisticated attack on the pathogen by producing specific molecules called antibodies that quell the infection. However, if too many antibodies are produced or the response goes awry, this can lead to them attacking our own cells, causing inflammation and autoimmunity. Our T lymphocytes can be further divided into Th1 and Th2 helper cells, T reg cells, and Th17 cells. Research has shown that it is the Th1 helper cells that we want to stimulate to help quell viral infections, whereas Th2 helper cells and Th17 cells, when stimulated actually contribute to more inflammation. In some cases, if left uncontrolled, this can lead to autoimmune
disease3. This is why we need to strive to have a balanced immune system that works well in the early stages of an infection to limit the infection and also a low level of general inflammation so that the process of activating both our innate and adaptive immune systems works in synergy4.
“Why We Need Immune Balance”
How do we achieve such a balance? The basic idea is that we want to strengthen our immune system so we have a greater activity of natural killer cells and macrophages at the very early stages of infection. However, we also want to have a generally low level of inflammation in our bodies, which can be achieved thru one’s diet, lifestyle, sleep pattern, and thru supplementation. If the level of inflammation is low, there is less of a chance for the adaptive immune system’s release of cytokines and antibodies to cause further inflammation and damage. For example, research has shown that people who already have a certain level of inflammation in their bodies, such as with co-morbidities of diabetes, heart disease, and asthma, are more susceptible to the cytokine storm that has been deadly in the COVID pandemic. We also know that one’s gut microbiome also plays a role in determining the health of one’s immune system and one’s level of inflammation4.
“Healthy Lifestyle for a Healthy Immune Balance”
There are many factors which contribute to a healthy immune balance. A suﬃcient amount of restful sleep, for example, promotes our Th1 helper cells to release interferon gamma, which supports an antiviral immune response5. In addition, when we are under a lot of physical and mental stress, our hormone levels of cortisol and norepinephrine increase.
Elevated cortisol levels can hurt our natural killer cells and Th1 helper cells, thereby impairing our immune system. Therefore, I recommend to my patients that they have some sort of relaxation practice, whether this is meditation, yoga, or simply being in nature, as these have all been shown to lower one’s cortisol levels6.
In terms of dietary therapy, we know that maintaining a healthy blood sugar and a healthy microbiome are key components for optimum immune health. Insulin resistance, obesity, and impaired glucose tolerance have all been associated with inflammation. In addition, having a low diversity of healthy bacteria in the gut has also been associated with inflammation. Therefore, I recommend a nutrient dense diet that is low in empty sugars and also rich in prebiotic and probiotic foods. Particularly important nutrients for a healthy functioning immune system include vitamin A, vitamin C, and vitamin D, so I recommend consuming foods rich in these or supplementing these vitamins.
“Bio-Normalizer and Immune Balance”
I find Bio-Normalizer (Fermented Green Papaya Enzyme) to be a great adjunct for immune health. As mentioned in my previous gut health article, Bio-Normalizer is a great source of prebiotics and probiotics, as well as digestive enzymes, which can contribute to a healthy gut and diverse microbiome. This is the first start to overall health and immune balance. Furthermore, research has shown that Bio- Normalizer helps to stimulate natural killer cells and macrophages to fight oﬀ infection in its early stages. In addition, Bio-Normalizer has been shown to neutralize inflammation-causing free radicals, such as superoxide and hydroxyl radicals. This helps the body achieve a natural balance, whereby we are fighting oﬀ pathogens but also neutralizing some of the general inflammation caused by the process. In my clinical practice, I find it a very useful adjunct to a healthy lifestyle and frequently recommend it for my patients.
🌿Dr. Miriam Mikicki is a Medical Doctor & General Practitioner practicing functional & integrative medicine. She helps patients find the root causes of their health issues, serving them locally in London and internationally through telemedicine consultations from her practice, Mikicki Medical. Dr Mikicki is a proud member of the Institute for Functional Medicine.
Disclaimer: The contents of this article are for information purposes only and do not constitute medical advice. Please consult your qualified healthcare professional to obtain advice suitable to your personal circumstances.
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Amsterdam: Elsevier/Academic; 2006.
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4 SF Yanuck et al., “Evidence Supporting a Phased Immuno-Physiological Approach to COVID-19 From Prevention Through Recovery,” Integrative Medicine Journal , 2020.
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