How Does the Immune System Work?

The recent COVID-19 outbreak has left us with a stern reminder of how important it is to have a fully functioning immune system. Your immune system is often the last line of defense between you, your body, and bacteria, viruses, fungi, and other damaging foreign invaders. To best take care of your immune system, it’s important to have a base-level understanding of your immune system and how it works. Here is some helpful information regarding what exactly it is that your immune system does and what could potentially damage it. 

How Does The Immune System Work?

Your immune system is activated when your body notices something in your body that shouldn’t be there. These unknown foreigners are known as antigens and include the proteins on the surfaces of bacteria, fungi, and viruses (1). Whenever an antigen attaches to a special receptor on an immune cell, several different functions are triggered throughout the body. 

These processes are crucial for your overall wellbeing. One of the most important processes is the information process, which occurs when your body comes in contact with a disease-causing germ. Your body will store information about the germ and how to fight it. This way, if your body ever comes in contact with the germ again it immediately recognizes it, allowing it to battle the germ quicker. 

What Are The 5 Parts of The Immune System?

You should think of your immune system like a well-oiled machine. There are many different moving parts, all of which play a key role in keeping you healthy and safe from foreign invaders. There are many different immune system parts but here are five of the most important parts:

  • White blood cells - Made in your bone marrow and are part of the lymphatic system. These blood cells move through your body searching for microbes such as bacteria, viruses, parasites, and fungi. If they come across any of these, they act fast to combat them (2)
  • Antibodies - Antibodies recognize antigens on the surface of the microbe or in the chemicals they produce, which mark the microbe as being a toxin
  • Complement system - This system is made up of proteins who work hard to complement the work done by antibodies
  • Lymphatic system - This system is made up of delicate tubes throughout the body. The goal of this system is to manage the fluid levels, react to bacteria, deal with cancer cells, and absorb fats in our diet from the intestine
  • Spleen - The spleen removes microbes and destroyed old or damaged red blood cells

Other parts such as the skin, lungs, digestive tract, saliva, and tears all play a big role in protecting you and your body from things trying to harm it. 

What Are The 3 Major Functions of the Immune System?

Without the immune system, our body would have no way of fighting off harmful things that enter our body from the outside. It would also be impossible for the body to protect itself from harmful changes that occur inside the body. Here are some of the main tasks of the immune system:

  • Fight disease-causing germs such as bacteria, viruses, parasites, and fungi, removing them from the body
  • Recognize and neutralize harmful substances from the environment
  • Fight disease-causing changes in the body, such as cancer cells

In order for the immune system to properly function, each moving part has to function at 100%. If something were to happen to any part, the entire system may shut down. That’s why it’s important to stay on top of your immune system, ensuring it’s always healthy. 

How Does The Immune System Work With Other Systems?

To better explain the immune system, think of it like a small police force that is tasked with patrolling every organ and tissue in your body. It works closely with the circulatory system for transportation and the lymphatic system for the production of lymphocytes. It is in constant communication with the other systems of your body to ensure that there are no foreign invaders that need to be addressed. 

Your immune system also works in unison with the largest organ in your body, your skin. Your skin is the first defense your body has against disease. The skin is full of cells and compounds that help kill any bacteria that appear. You can help your immune system and your skin prevent illness by washing your hands and showering frequently. 

Can Stress and Anxiety Affect Your Immune System?

We all deal with anxiety from time to time, in fact, it’s completely healthy for our brain to deal with small bouts of anxiety. However, chronic anxiety can greatly interfere with your quality of life and can even weaken your immune system. This is because anxiety can trigger your flight-or-fight stress response, releasing hormones such as adrenaline into your system. 

This increase in adrenaline can increase your pulse and breathing rate so your brain can get more oxygen. Again, if this only happens from time to time it can actually help boost your immune system. However, if you repeatedly feel anxious your body may never get the signal to return to normal functioning. This can lead to a weakened immune system, leaving you more vulnerable to infections and illness. 

What Are Three Immune Disorders?

Researchers believe that there are more than 80 different autoimmune diseases, each of which affects the immune system in different ways. Some of these disorders can be present from birth while others may develop over time. Experts are still unsure as to what exactly causes these disorders. Here are three of the most common immune disorders:

  • Multiple sclerosis (MS) - This disorder damages the myelin sheath, the coating that surrounds the nerve cells in your central nervous system. Damage to this sheath will slow the transmission speed of messages between your brain and spinal cord to and from the rest of your body
  • Type 1 Diabetes - With type 1 diabetes, the immune system attacks and destroys insulin-producing cells in the pancreas
  • Rheumatoid arthritis (RA) - With RA, the immune system turns on itself, attacking the joints. This will cause redness, warmth, soreness, and stiffness in the joints. This can start as early as your 30s or sooner

Symptoms like fatigue, muscle aches, swelling, and redness could be signs of an autoimmune disease. Symptoms might come and go over time. Keep in mind, these symptoms are also common in other diseases and ailments. It’s best to consult with your doctor to better understand what’s going on with your body. Some other disorders include celiac disease, pernicious anemia, myasthenia gravis, Graves’ disease, and Addison’s disease. 

Supplements Can Help The Immune System

There are several processes our body uses to remove antigens. One of the protective systems involves our bodies producing macrophages, those macrophages engulf the antigen, and then the antigen is digested (destroyed) through a process of autophagy. Early studies show that spermidine triggers cellular autophagy, which can play a major role in helping to build more robust immune defense through healthier cells and increased autophagic strength and function.

The positive impacts of spermidine-induced autophagy and spermidine supplementation have been studied worldwide. In addition to boosting our immune system, spermidineLIFE® offers remarkable supplemental support for the health of our brain, heart, bones, muscles, weight, hair, liver, and overall longevity.



  1. How does the immune system work?
  2. Immune system explained
  • Don Moxley - Director of Applied Science

    Don Moxley is the Director of Applied Science at Longevity Labs. Moxley draws upon his career as an athlete, a sports scientist, and an instructor to lead and educate on the science of autophagy and longevity.