WHAT IS IMMUNITY AND HOW CAN WE BEST SUPPORT IT?
What is the immune system?
The immune system is a complex network of organs, cells and proteins that work together to defend the body against invaders, such as bacteria, viruses, fungi and toxins. Immune cells act as your body’s first line of defence – they recognize, identify and neutralize any harmful substances (environmental or pathogenic) that have found their way into your body.
How does our immune system work?
The immune system is activated when it encounters a pathogen (an organism that causes disease) which our body does not recognise. These are called antigens. When this happens, the immune cells attach themselves onto the antigens which then triggers a series of processes in the body to destroy these invaders.
The immune system has an incredible memory, remembering every invader it has previously fought so that it can easily recognise and destroy it if it re-enters the body again. That is why some diseases, such as chickenpox, you only get once as the body has a chickenpox antibody stored, ready and waiting to destroy it next time it enters the body. This is called immunity. Similarly, this is how vaccines work. Vaccines expose your immune system to a small, non-harmful, amount of a specific pathogen so that if your body encounters this pathogen in the future, it is able to recognise it immediately and destroy it quickly.
In addition, the endocannabinoid system is a complex nerve cell signalling system that modulates the central nervous system’s function and helps maintain homeostasis (state of equilibrium in the body in which all the organs function optimally). It is widely expressed in the body, including the immune system, where the endocannabinoid receptors, specifically CB2 receptors, significantly influence immune functions. CB2 receptors are found primarily in immune cells and in the gut and help regulate inflammation and antipathogen immune responses .
Everyone’s immune system is different, but in general it becomes stronger during adulthood as by this time our bodies have been exposed to more pathogens and thus developed more immunity.
How can we support our immune system?
A healthy immune system requires adequate nutrition. Diets should include plenty of vitamin A, B6, C and D, zinc, selenium, iron, copper, magnesium. Sufficient protein intake is also important for antibody production. Deficiencies in nutrition can impact the functioning of the immune system.
Exercise has important modulatory effects on our immune system function such as reducing inflammation and stress.
Stress can negatively impact our immune response as it raises your cortisol levels which can weaken your immune system if they stay high for too long. Stress can also damage your body’s own cells and trigger responses from your immune system such as elevating inflammation, making you more susceptible to viruses and infections.
There is an extensive interplay between our gut microbiota and immune system. As we know, most of the human microbiota resides in the gut. But as it turns out so does 70-80% of the body’s immune system. The relationship between the two is symbiotic, working together to promote a healthy body.
Getting enough sleep is crucial for maintaining a healthy immune system. During sleep your immune system releases proteins called cytokines. Certain cytokines are required when you have an infection or inflammation, or when you are under stress. Lack of sleep can decrease production of these protective cytokines.
The immune system is incredibly complicated and vital for our survival. Several different systems and cell types work in perfect synchrony (most of the time) throughout the body to fight off pathogens and clear up dead cells. So, look after your immune system!
This article is not intended to provide medical advice and is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment.
1. Immune System. Betterhealth.vic.gov.au (2021). Retrieved 7th September 2021 https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/immune-system
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3. Gombart, A, F., Pierre, A., and Maggini, S., (2020) “A Review of Micronutrients and the Immune System – Working in Harmony to Reduce the Risk of Infection”, Nutrients, 12 (236), doi:10.3390/nu12010236