Gut Health and Immunity

Gut Health and Immunity

We take a look at the relationship between your gut and your immune system.

Your immune system is incredibly important. While you may only notice it when you’re not feeling very well, your body’s immune system is constantly working in the background to keep you healthy. Think of it as your invisible shield, your natural defence system.

 Our understanding of the immune system has come a long way in the last few decades, and one of the most exciting discoveries is how gut health is linked to immunity. It turns out that your immune system is inextricably linked to your gut and what happens in your gut has a big effect on your immune system.

How Does the Immune System Work?

To understand the role gut health plays in your immune system, it helps to understand the basics. Think of your immune system as just that - a system.  It is a dynamic network of cells, molecules, proteins, tissues and organs that work together to protect your body from disease and infection [1].

From birth you are equipped with an innate immune system, while your adaptive immune system is constantly accumulating ‘memory’ and learning to differentiate between harmful and useful substances throughout the course of your life. It is also learning how to balance between initiating a response or deciding to tolerate the environmental organisms that it comes into contact with. This continuous adaptation ensures you’re protected from pathogens, but that you’re not an inflamed mess every time you encounter something new.

Your Immune System and Your Gut

When it comes to gut health, it is the cell section of the immune system that is the main focus. The cell part of your immune system is made up of five different types of white blood cells that each play a role in protecting your body [2]. Some cells, such as the B cells, release antibodies to defend against harmful invading cells, while CD8 killer T cells destroy thousands of virus-infected cells in the body every day.

“A huge proportion of your immune system is actually in your GI tract,” says Dan Peterson, assistant professor of pathology at the Johns Hopkins University School of Medicine. This huge proportion is mainly down to the immune cells. In fact, more resident immune cells reside in your GI tract than anywhere else in the body [3]. These cells come from the lymphoid branch of the immune system and it is their job is to attack harmful invaders.

So how exactly does your immune system and gut work together? To start, there is a constant interaction between our body’s immune system and bacteria in our guts. It is as if the bacteria found in the gut mucosa ‘talks’ to the immune cells to trigger a set of responses.

Let’s take T-cells for example. These immunity powerhouses are essential in helping fight infection, disease, and cancer. They perform a variety of functions, and that particular function is determined by the biochemical signals they receive. In the case of T1 cells, scientists have found that they are stimulated both in production and activity by a species in the human gut called Bacteroides Fragilis. Once stimulated they will get to work clearing pathogenic microbial incursions.

This is just one example of the interdependent relationship between microbes and your immune system. Our bodies are smart, and our immune systems are pretty good at controlling the microbial community so that a certain microbial load is tolerated. Of course, there will be times with this balance is out of whack, but when functioning properly, your immune network works together to ensure that ‘bad’ bacteria rarely breach the intestinal barrier and if they do invade, they are killed rapidly [4].

The Importance of Gut Health

A healthy and happy gut is one that is home to a diverse microbiome. Our gut microbiomes are home to trillions of organisms that play essential roles in your immune system. And what you eat can directly determine the levels of bacteria in your gut.

Having a healthy balance of good bacteria in your gut can help your immune system effectively and efficiently do its job. Gut-friendly flora also seem to enhance the effectiveness of immune cells and boost the overall defence of the intestinal walls to prevent pathogens and infections from being absorbed [5].

What is the best way to maintain a healthy gut? As with most things in life, it is all about balance. Your diet can either strengthen your immune system or take away from its defensive capabilities.

A gut-friendly diet is one that consists of natural, whole foods. A varied diet full of fruits and vegetables will ensure you are getting enough nutrients and prebiotics while adding in foods high in probiotics will introduce ‘friendly’ bacteria to your gut.

To Sum it Up

The interaction between your gut and your immune system is complex, and scientists are still making new discoveries to enhance our understanding. While there isn’t one magic potion to enhance immunity, we do know that a healthy gut supports a healthy immune system.

We’ll continue to follow the latest research and keep you posted on any new information. If you have any questions about immunity or gut health, feel free to send us a message. We would love to hear from you.

Sources

https://www.hopkinsmedicine.org/research/advancements-in-research/fundamentals/in-depth/the-gut-where-bacteria-and-immune-system-meet

https://www.cancerresearch.org/blog/april-2019/how-does-the-immune-system-work-cancer

https://www.foodmatters.com/article/your-gut-and-immune-system-connection-recipe-giveaway

https://www.gutmicrobiotaforhealth.com/immunology-in-the-gut-mucosa-a-video-animation-from-nature/

https://www.sciencedirect.com/topics/medicine-and-dentistry/intestine-mucosa https://sciencenordic.com/denmark-forskerzonen-gut-bacteria/how-our-gut-influences-our-health/1454808

https://www.nature.com/articles/s41385-019-0160-6

https://www.sciencedirect.com/science/article/pii/S0032579119579226

https://www.britannica.com/science/T-cell

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7012204/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3337124/

https://www.nature.com/articles/nature10213