You’ve probably heard the phrase “trust your gut,” but did you know that your gut health is not only essential for digestion but also plays a key role in your immune system? In fact, your gut and immune system are closely connected, working together to keep you healthy.
What Is Gut Health?
Your gut refers to your digestive system, which includes your stomach, small intestine, large intestine, and other organs involved in digestion. Inside your gut, there are trillions of microorganisms (bacteria, fungi, viruses, and more) living together in what’s called the gut microbiome. Think of it as a tiny ecosystem that helps digest food, fight harmful germs, and even produce vitamins.
The Gut-Immune System Connection
So, how exactly does the gut influence your immune system? Well, a large part of your immune system is actually located in your gut. In fact, about 70-80% of your immune cells are in your intestines (Sadeghi et al., 2020). This means that the health of your gut can have a major impact on how well your body can defend against infections, viruses, and even chronic diseases.
Your gut microbiome works as a gatekeeper, deciding which bacteria, viruses, and other harmful invaders can enter your body and which ones should be kept out. When your gut is healthy, it helps keep your immune system strong. But when your gut is unbalanced, it can lead to inflammation, immune system dysfunction, and even increased risk for illness.
How Poor Gut Health Affects Immunity
An imbalance in the gut microbiome—called dysbiosis—can negatively impact your immune system in several ways:
Increased Inflammation
When your gut microbiome is out of balance, it can cause chronic inflammation, which is linked to a weakened immune response. Chronic inflammation is thought to contribute to conditions like allergies, autoimmune diseases, and even cardiovascular diseases (Rizzo et al., 2018).
Weakened Immune Defence
A disrupted gut microbiome can impair your gut’s ability to function as a defence barrier. This may make it easier for harmful bacteria, viruses, and toxins to pass through your gut and into your bloodstream, potentially leading to infections or other health issues (Mayer et al., 2014).
Higher Risk for Autoimmune Conditions
Dysbiosis has also been linked to autoimmune diseases, where the immune system mistakenly attacks the body’s own cells. Research suggests that an imbalance in the gut microbiome may trigger this process by influencing the immune system inappropriately (Vitetta et al., 2017).
How to Support Gut Health and Boost Your Immune System
The good news is that you can support both your gut and immune health through lifestyle changes, particularly by making better food choices. Here are some simple ways to take care of your gut:
Eat a Fibre-Rich Diet
Foods high in fibre, especially fruits, vegetables, whole grains, and legumes, help feed the beneficial bacteria in your gut. These fibre-rich foods act as “prebiotics,” which nourish healthy gut microbes and promote a balanced microbiome (Sonnenburg et al., 2016). A healthy microbiome, in turn, helps strengthen your immune system.
Include Probiotic Foods
Probiotics are live beneficial bacteria that may improve gut health. They can be found in fermented foods like yoghurt, kefir, sauerkraut, and kimchi. Probiotics may help maintain a healthy balance of gut bacteria, which is essential for immune function (O’Hara & Shanahan, 2006).
Stay Hydrated
Drinking plenty of water is essential for maintaining a healthy gut. Proper hydration helps support digestion and the growth of good bacteria in the gut, keeping everything running smoothly.
Limit Processed Foods and Sugar
High sugar intake and processed foods can disrupt the balance of your gut microbiome by promoting the growth of harmful bacteria. Reducing sugary and highly processed foods in your diet may help prevent gut imbalances and inflammation.
Manage Stress
Stress negatively impacts gut health by increasing inflammation and altering the composition of the gut microbiome. Chronic stress can weaken the immune system, making it harder to fight off infections. Practicing stress management techniques like yoga, meditation, or deep breathing may help protect your gut and your immune system (Mayer, 2011).
Get Enough Sleep
Sleep is crucial for both gut and immune health. Research shows that poor sleep can negatively affect gut microbiota diversity, which in turn can impair immune function. Aim for 7-9 hours of quality sleep per night to support both your gut and immune system (Opie et al., 2018).
Your gut health is closely linked to your immune system. When your gut is healthy, it helps protect you from infections and supports your body’s natural defences. But when your gut is out of balance, it can lead to immune system dysfunction and increased risk of illness. By eating a balanced diet rich in fiber, probiotics, and healthy foods, along with managing stress and getting enough sleep, you can support both your gut and immune system for better overall health.
Remember, a healthy gut isn’t just about what you eat—it’s about maintaining balance. By nurturing your gut, you’re also giving your immune system the support it needs to keep you feeling your best.
References
Mayer, E. A. (2011). Gut feelings: The emerging biology of gut–brain communication. Nature Reviews Neuroscience, 12(8), 453-466. https://doi.org/10.1038/nrn3071
Mayer, E. A., Knight, R., & Mazmanian, S. K. (2014). Gut microbiome in health and disease. Nature Reviews Gastroenterology & Hepatology, 12(5), 317-328. https://doi.org/10.1038/nrgastro.2015.35
O’Hara, A. M., & Shanahan, F. (2006). The gut flora as a forgotten organ. EMBO Reports, 7(7), 688-693. https://doi.org/10.1038/sj.embor.7400731
Opie, R. S., & Pipingas, A. (2018). Sleep and gut health: A growing relationship. Frontiers in Neuroscience, 12, 35. https://doi.org/10.3389/fnins.2018.00035
Rizzo, G., D’Antona, G., & Fadda, M. (2018). Inflammation and the gut: An emerging approach in autoimmune diseases. The Journal of Nutritional Biochemistry, 61, 93-100. https://doi.org/10.1016/j.jnutbio.2018.06.003
Sadeghi, N., & Keshavarzian, A. (2020). The gut microbiome and immune modulation. Current Opinion in Gastroenterology, 36(1), 9-17. https://doi.org/10.1097/MOG.0000000000000624
Sonnenburg, E. D., & Sonnenburg, J. L. (2016). The human gut microbiome: From association to modulation. Cell, 164(4), 835-848. https://doi.org/10.1016/j.cell.2016.02.020
Vitetta, L., & Saltzman, E. (2017). Gut microbiome and immune modulation: Therapeutic potentials. Journal of Clinical Gastroenterology, 51(9), 755-762. https://doi.org/10.1097/MCG.0000000000000863