What is your immune system? You probably only think about your immune system when colds and flu are doing the rounds.But it is working all the time to guard you against foreign invaders, mounting constant attacks to defend your body without you even noticing.1 It’s a huge, complex network of cells, organs, proteins, and antibodies – known as immunoglobulins – designed to prevent your body from invasion by bacteria, viruses and parasites.
In fact, it saves your life on a daily basis: it’s your immune system that launches an attack when it detects something that shouldn’t be there. Your immune system also shifts dead or faulty cells out of the body, and, if working correctly, it recognises normal, healthy tissue and leaves it alone.2 Whilst we usually only think of our immune system when we feel ill, it’s actually working every day to keep us safe.3
Meet your immune system’s key players White blood cells, also called leukocytes, roam your body, monitoring the presence of pathogens – organisms which can give us diseases. White blood cells are produced and stored in the following organs:4
lymph nodes, spread throughout the body
thymus gland, in your neck
spleen, found above the stomach
There are two main types of white blood cells:
These break down and eat pathogens. Phagocytes include:
macrophages – they patrol for foreign bodies and remove waste cells
neutrophils – these attack bacteria
Lymphocytes, or effector cells
Produced in bone marrow, lymphocytes remember previous invaders and mount an attack as soon as they detect their presence again. There are:
B-cells – these act as lookouts, keeping an eye out for pathogens and sending alerts
T-cells – they receive signals from B-cells. Helper T-cells coordinate the immune response, while natural killer T-cells destroy infected cells5
Mast cells are a separate group of cells that are important in allergy. Their job is to heal wounds, but they also release a substance called histamine that can trigger allergy symptoms.
Why is my immune system so important? Your immune system offers protection against all kinds of infections, allergies and diseases. It looks out for anything harmful that enters your body, picks it up and fights back.
There’s a wide range of things that can spark your immune system into action – an allergen such as pollen, a virus causing a cold, a cut from a fall. But whatever the problem, your immune system is what’s powering your ability to heal and recover.
When your immune system is in tip-top condition, you probably don’t even notice it working away to protect you around the clock.
However, you will know when there’s something wrong as your immune system is your body’s in-built defence system against illness and infection. If you feel good today, thank your immune system (and give yourself a pat on the back for looking after it!).
If you have ever wondered what your immune system does and why it is so important then this article should help shed some light.
The immune system basics The main purpose of your immune system is to protect your body from viruses and bacteria.
Without it, they would have free reign and you would be constantly falling ill. Your immune system works by recognising the difference between your body’s cells and alien cells, allowing it to destroy any that could be potentially harmful. This usually works well but can cause problems if your immune system wrongly classifies some of your own cells and attacks them instead.
Why exactly do you need a healthy immune system? A robust and properly functioning immune system helps you go about daily life as you come into contact with germs and bugs from pets, other people, and your environment.
Without a healthy immune system, you could pick up infections and infectious diseases more easily, and the effects could be serious – even fatal.
Your body’s first line of defence is its physical barriers. If viruses and bacteria manage to break through, there are specialised cells that will jump into action. Your bloodstream and key areas of your body contain white blood cells that can fight and destroy the viruses and bacteria they find.
Sometimes, our immune system can overreact and even attack your body’s own cells. This is what happens in the case of allergies like hay fever and autoimmune diseases. It is why donated blood and organs must be very careful matched.
It is easy to take the immune system for granted because it does such a good job at keeping us free from infection around the clock! If you’ve got a healthy immune system, look after it and it will look after you.
We need a healthy immune system to help avoid contracting infections and infectious diseases
Our immune system is a complex network of cells, organs, proteins, and antibodies that launches an attack when it detects something that shouldn’t be in the body
White blood cells track down and devour harmful pathogens