The Immune System

Three happy, healthy men used as a metaphor for a healthy immune system
How to boost your immune system

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What is the Immune System?
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The immune system is a very complex part of our bodies. It’s like a defense team that fights off germs and keeps us healthy. When you get a cut or a scrape, it’s also responsible for helping you heal. Without it, we wouldn’t be able to fight off infections, or even heal from small injuries.

What makes up the immune system?
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White Blood Cells

White blood cells are like the soldiers of our body. They move around in our blood and lymphatic vessels, always on the lookout for harmful invaders. When they find one, they multiply and signal other cells to do the same.

There are two main kinds of white blood cells: phagocytes and lymphocytes.

  • Phagocytes engulf and break down invaders, acting like bodyguards.
  • Lymphocytes have a memory of past infections, so they can recognize and fight off invaders more effectively if they come back. This is called the adaptive part of our immune system.

There are two important types of lymphocytes: B cells and T cells. B cells make antibodies and alert T cells about invaders. Then, T cells destroy infected cells and help other white blood cells get into action.

Special Organs Involved in the Immune System

The thymus is located in the upper chest behind the breastbone. It makes and matures T cells, which are important white blood cells that fight infections.

The spleen is an organ that filters blood, getting rid of old or damaged red blood cells. It also stores white blood cells.

Bone marrow makes and stores white blood cells, including B cells.

Lymph nodes are spread throughout the body and are connected to lymphatic vessels. They also make infection-fighting white blood cells.


Antibodies, also called immunoglobulins, are big Y-shaped proteins made by the immune system’s memory cells. They’re produced when the immune system encounters unfamiliar substances called antigens. These antigens trigger a response where the immune cells attack, break down, and remember them. Later, if the immune system faces the same antigen again, it quickly releases antibodies to fight it off. Essentially, antibodies act like the search-and-destroy team of the body’s defense, targeting specific invaders.

The Complement System

This is a group of proteins that only exist to help antibodies do their job.

The Lymphatic System

The lymphatic system has three main jobs: fighting bacteria, controlling body fluids, and getting rid of cell waste that could make us sick. It’s made up of lymph nodes, vessels, and white blood cells.

Signs you have a compromised immune system
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If any part of the immune system isn’t working well, it can cause problems because it relies on many of the body’s functions. Here are signs that your immune system might not be working right:

  • High stress levels. Stress can weaken your immune system, making it easier to get sick.
  • Getting colds, flu, or infections often.
  • Having digestive problems or frequent stomach bugs.
  • Wounds taking a long time to heal.
  • Feeling tired and low on energy all the time.
infographic showing the signs of a compromised immune system

How to keep your immune system healthy
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  • Sleeping well is extremely important. Not getting enough sleep can affect your nerves and immune system.
  • Eating healthy food like fruits, veggies, nuts, and healthy fats helps keep your body strong and ready to fight off bugs.
  • Fermented foods like pickles and kimchi are good for your gut and help protect against bad bacteria.
  • Try not to eat too much junk food with added sugars, as it can mess with your immune system.
  • Doing some moderate exercise is good for your immune system.
  • Drink plenty of water – it’s good for you!
  • Try to keep your stress levels in check.
  • Washing your hands and keeping your mouth clean are also important for staying healthy.
  • If you want to give your immune system an extra boost, you can take some supplements like zinc, vitamin C, vitamin D, folic acid, iron, and probiotics.

Zinplex range of white blood cells and immune system boosting supplements

Immune system and white blood cells brochure Medical references

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