What’s it all about?
The immune system is incredibly complex and absolutely vital for our survival as we are exposed to millions of potential pathogens daily, through contact, ingestion, and inhalation. Several different organs, cells, tissues, and proteins are working around the clock, in perfectly synchronising throughout the body to ward off threats.
The general belief that the immune system is something we can easily manipulate, or “boost” is called into question when you realise how complicated it really is. There are hundreds of different types of cells in the immune system doing a variety of jobs. Some identify attackers, some carry messages, some destroy known bacteria and others learn how to combat new enemies. Which cells would you boost? Why boost them? How do I boost them?
First, let’s understand what COVID-19 is and see what Lifestyle Habits can be implemented to keep us fit and healthy, then, let’s take a closer look at the wonders of the immune system and how it works.
What is COVID-19?
COVID-19 is the name of the disease caused by the new strain of coronavirus, a severe acute respiratory syndrome (SARS-CoV-2). Currently, there is no vaccine, meaning our body has to fight this battle on its own for now. When we have a vaccine, our acquired immune system will have responded to the vaccine’s antigens and subsequently developed the required cells to fight back early, thus preventing the coronavirus from developing and doing harm.
In the meantime, given the current situation with COVID-19 and the return to our day-to-day lives, health is on everyone’s mind and we are all wondering “What can I do better to protect myself?”. The first answer would be “I can boost my immunity”, but …Is there such a thing without a vaccine? The answer is YES.
Fortunately, there are some key lifestyle habits that when implemented, can enhance our immune response, making us less susceptible to illnesses and excessive immune responses.
The 5 Key Lifestyle Habits for Immunity
A healthy balanced diet filled with a variety of fruits and vegetables, low-fat meat and dairy, nuts and some vegetable oils will provide all necessary nutrients without adding any supplements. If your diet contains high levels of refined sugar, trans fats, salt, and numerous food additives, it will be detrimental for health by impairing your immune system.
There are several nutrients that have been scientifically proven to promote an optimal immune system. They are essential amino acids, the essential fatty acid linoleic acid, vitamin A, D and E, B6, B9, B12, vitamin C, Zn, Cu, Fe and Se.
One exception when it comes to supplements is vitamin D. It is produced within the body when ultraviolet rays from sunlight strike the skin, therefore, a deficiency is very common during fall and wintertime.
- Physical Activity
Regular exercise of 20minutes at a moderate to vigorous intensity each week can make all the difference e.g. EMS training. The immune system’s first line of defence against disease is the lymphatic system. Physical activity stimulates the lymphatic system by increasing your heart rate and causing your muscles to contract. This response becomes the pump that helps the lymph fluid travel around your body (and the antibodies and lymphocytes contained within). Exercise can help the lymphatic system flow more effectively and help prevent infections and diseases from taking hold.
Ensure you get a minimum of 8 hours sleep each night. Studies that investigated sleep’s effect on the immune system found that even a slight reduction of sleep time can have massive consequences on the number of white blood cells. For example, specific cytokines need to increase when you have an infection or inflammation, or when you’re under stress. Sleep deprivation leads to a decrease in the production of these protective cells. Furthermore, antibodies are reduced during periods of sleep deprivation.
Stress is key for survival, but too much stress can be harmful. Take time out of your day to destress. Do activities you enjoy, employ relaxation techniques, manage your time, talk to friends and family. All of these can avoid prolonged periods of stress, thus avoiding hyper physiological levels of cortisol, which in turn weakens the immune system. Additionally, excessive cortisol can lead to fatigue, poor skin, muscle weakness, anxiety and depression, all of which can in turn negatively impact our immune system.
- Smoking & Alcohol intake
In simple terms, smoking and alcohol are to be avoided wherever and whenever possible. Alcohol misuse is known to increase susceptibility to infection – it affects the structure and integrity of the GI tract, facilitating leakage of microbes into the circulation. Secondly, it lowers the function and count of your white blood cells, thus increasing your risk of infection. Smoking causes an array of health issues, for example, the nicotine increases cortisol levels similar to that of stress, subsequently reducing the immune system’s response.
In simple, have a good nights sleep, prepare some healthy meals and snacks coupled with some daily exercise, avoid alcohol and smoking, and do the activities you enjoy to keep stress out of your life….your immune system will thank you for it!
Understanding your Immune System
This system can broadly be divided into two branches:
- The Innate
- The Acquired.
Innate Immune System
The innate system judges friend from foe, and provides an immediate line of defence, acting within minutes of infection. It is present from birth and has no memory.
This innate immunity system includes:
- Physical Barriers – Skin, the gastrointestinal tract, the respiratory airways and lungs, cilia, blood-brain barrier, eyes, eyelashes and other body hair.
- Defence Mechanisms – Secretions (mucus, saliva, tears, bile, gastric acid), desquamation of the skin, gut flora and many others.
- General Immune Responses – Inflammation, complement system and non-specific cellular responses.
Adaptive Immune System
The adaptive system responses are induced during the first weeks after infection. This system targets specific threats and learns how to launch precise responses against viruses or bacteria, it adapts to the new threat. The adaptive system is capable of memorising a specific pathogen, setting up a rapid and effective response should it be encountered again (the basis of vaccination and antibodies).
The main cells of the adaptive immune system are T and B lymphocytes (lymphocytes are a subtype of white blood cells).
Found in the blood, lymph nodes, spleen, tonsil and other mucosal tissues. They play an important role by producing antibodies. For example, some B-cells can make antibodies that target COVID-19 or regular influenza, whilst other B-cells produce antibodies that target bacteria related to tuberculosis.
T-cells originate from bone marrow and mature in the thymus. They do not utilise antibodies to fight pathogens, but their cell membranes are populated by specific receptors (T-receptors) that recognise the various types of specific antigens (substances that provoke an immune response).
- Cytotoxic T-cells – theses cells have sacs containing chemical substances that cause target cells to burst open. They are the cause of transplant organ rejection, for example.
- Helper T-cells – support other immune cells (stimulating the production of antibodies by B-cells, or activating cytotoxic T-cells). For example, Helper T cells are targeted by HIV. HIV infects helper T cells and destroys them by triggering signals that result in T cell death.
- Regulatory T-cells – inhibit the activity of B cells and T cells towards the antigens. Basically, they are responsible for making peace on the battlefield once the enemy had been defeated. Abnormal activity of the Regulatory T cells leads to autoimmune diseases.
- Natural Killer T-cells (NKT) – they differentiate infected or cancerous cells from normal body cells. Dysfunction in NKT cells activity has been shown to lead to the development of autoimmune diseases and cancers.
- Memory T-cells– they are stored in the lymph nodes and spleen and may provide lifetime protection against a specific antigen in some cases (measles). They identify previously met antigens and react to them more rapidly and for a longer period of time.
Our Immune System Summarised
- The immune system is an incredibly complicated network that works continuously to protect the body from potentially harmful foreign invaders.
- Innate immunity is the natural protection that we are born with, and is our first line of defence against infection.
- Producing extra mucus, tearing, increasing body temperature (fever), redness and pain are non-specific responses that come into play immediately or within hours of an antigen’s appearance in the body.
- When the first line of defence is bypassed, evaded, or overwhelmed, an induced or adaptive immune response is
- Adaptive immunity is the protection that we gain throughout life as we are exposed to infections or protected against them with vaccines. It is much slower to react, but it is specific just like special forces – take longer to mobilize but are better trained.
- Right now, no vaccine is available for COVID-19, so it is of vital importance to ensure we do what we can to support our immune system; Follow the 5 Key Lifestyle Tips
- Janeway CA Jr, Travers P, Walport M, et al. Immunobiology: The Immune System in Health and Disease. 5th edition. New York: Garland Science; 2001. The complement system and innate immunity.Available from: https://www.ncbi.nlm.nih.gov/books/NBK27100
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