THE LYMPHATIC SYSTEM AND IMMUNE SYSTEM HEALTH

While we often talk about the immune system, it can be hard to visualise exactly what it is and how it works in practice.

The immune system is one of the most incredible and complex systems in the body, able to spring into action in defence against harmful ‘invaders’ (like bacteria and viruses) within minutes by releasing antibodies.

As one of our most important health assets, it therefore makes sense to do all we can to support and even boost our immunity.

Inside the body, the immune system is made up of an ‘army’ of special cells. These defenders each have different functions and are located in different areas of the body. For instance, some do their work in the bloodstream, tonsils, appendix and spleen, while others work in the gut and lymph nodes.

For the purposes of this article, we are going to look at the specific role of the lymphatic system in supporting immunity.

What is the lymphatic system?

The lymphatic system is made up of:

Lymphocytes: These are a form of small white blood cell that determine the type of immune response to infectious microorganisms and other foreign substances that enter the body.

Lymph: This is a clear fluid, which bathes the tissues and carries immune cells (such as B and T lymphocytes). The lymphatic system collects excess fluids, nutrients, gases, ions, hormones, enzymes and plasma proteins from surrounding tissues and returns them to the blood circulation, once pathogens, toxins and waste matter have been filtered out.

Lymph vessels: Fluids move out of our blood capillaries into tissue spaces, and then into lymph capillaries. These then join to form larger lymph vessels. The lymph vessels carry lymph.

Lymph nodes: Located along the lymph vessels, these are small glands interspersed along lymphatic vessels. They act as collection sites and cleaning filters, which form part of an immune system response against infection. Lymph must pass through them, before entering the blood.

Tonsils: Tonsils are the two lymph nodes located on each side of the back of your throat. They function as a defence mechanism, helping to prevent infection from entering the rest of your body.

The thymus gland: Located behind the sternum and between the lungs, this gland is only active until puberty. After puberty, the thymus starts to shrink and is gradually replaced by fat. Thymosin is the hormone of the thymus, and it stimulates the development of disease-fighting T cells.

Peyer’s patches: These are small masses of lymphatic tissue found in the small intestine. They form an important part of the immune system by monitoring intestinal bacteria populations and preventing the growth of harmful bacteria in the intestines.

Did you know that arguably the most important part of your immune system is in your gut? A massive 70% of all antibody-producing cells are located in Gut Associated Lymphoid Tissue (GALT), found in the intestine. GALT is considered the largest collection of immune cells in the body.

The spleen: The spleen is an organ found on the left-hand side of your upper abdomen. Its main functions are to filter the blood, create new blood cells and store platelets. It is also a key part of the immune system.

What does the lymphatic system do?

Aside from maintaining fluid balance in the body and absorbing fat from the digestive tract, the lymphatic system’s primary functions are to:

1. act like a ‘garbage collection’ service for the body, filtering the bloodstream of toxins and waste;
2. fight infection – as we have already mentioned, the lymph nodes contain high levels of white blood cells that engulf bacteria. If we have an infection, the nodes closest to the site enlarge as the white blood cells multiply inside them. This is why lymph nodes (for example in the neck, armpits and groin) often become inflamed during illness – this means they are doing their job!

So with this in mind, it is easy to see how the lymphatic system plays a crucial role in removing toxins and pathogens from the body and thereby generally supporting the immune system.

Keep that lymph moving!

One of the most important things to know about the lymphatic system is that it does not have a circulatory ‘pump’ equivalent to the heart. However, given that it is a collection point for many toxins and waste products, it is obviously important to keep these undesirable substances moving, ultimately heading for elimination out of the body.

You might be surprised to learn that we have approximately three times the amount of lymph fluid in our bodies than we do blood. In contrast to blood, which is pumped around by the heart’s contractions, lymphatic fluid generally flows around our body against gravity. But how does this happen?

Three things help to keep lymph moving: the contractions of surrounding muscles during exercise or physical activity (this can increase lymph flow by up to 15 times); contractions of smooth muscle in the lymph vessel walls; and movements of the chest when breathing.

This therefore highlights the importance of keeping active and breathing deeply – by doing so, you will be supporting lymphatic drainage and helping to cleanse your immune system!

The average modern lifestyle, filled with stress, work pressures, family pressures, lack of exercise, environmental toxins and unhealthy foods can all place a huge strain on our toxic loads and, therefore, the lymphatic system on a daily basis. A sensible exercise regime and healthy diet can go a long way towards lessening this burden.