The Link Between Gut Health and Immunity
It’s commonly known that a balanced gut is beneficial for general health, but what many don’t know is that gut health is closely connected to the immune system. In fact, 70% of your immune system is located in your gut. That means that your immune cells are directly exposed to your gut microbiome (the combination of good and bad bacteria). If this is balanced and healthy, your immune system will thrive. If not, you’ll likely get sick more and may even experience an autoimmune disease.
Autoimmunity
The immune system is designed to defend and attack against harmful pathogens. When operating within a healthy microbiome, this process should occur without a hitch. However, when the gut is unbalanced or lacking in diverse bacteria, your immune system is more susceptible to faulty responses. In these cases, the immune system attacks the healthy cells in your body, mistakenly identifying them as pathogens. In turn, this causes inflammation in the part of your body the immune system is attacking.
In unhealthy microbiomes, the immune system is susceptible to attacking the healthy cells of the gastrointestinal tract, causing inflammation and a host of other side effects. Though GI-related autoimmune diseases are common, an unhealthy microbiome can also produce an autoimmune response outside of the GI tract, such as in the skin (psoriasis) or in the joints (rheumatoid arthritis), among many others.
The key to preventing autoimmune diseases is prioritizing the health of your gut through your diet.
Diet
The type of food you eat is the key determinant in the makeup of your gut microbiome. Good bacteria in the gut rely on the food the rest of the body can’t digest in order to grow. That’s why fiber and fermented foods are the best fuel sources for a healthy gut. Not only are they good at nourishing good bacteria, but they also prevent the growth of bad bacteria.
Fiber
Your gut needs fiber to promote the maturation of good bacteria. It also uses fiber to reduce inflammation, which will help keep the immune system in check. One study showed that eating fruits and vegetables regularly decreased the growth of harmful bacteria.
Best sources of fiber include:
Beans
Broccoli
Citrus fruits
Berries
Nuts
Whole grains
For those with digestive autoimmune diseases like crohn’s disease, ulcerative colitis or IBS, certain fiber sources can be difficult to eat, and may even cause a flare up. In these cases, it’s important to develop a personalized diet that works for you. Fortunately, there’s a wide range of foods that contain fiber, and some are easier to digest than others. For example, citrus fruits, barley, rice, potatoes, melons and bananas are among the easier-to-digest options. You can also remove the skin and bake fruits and vegetables, which makes them easier for your GI tract as well.
Probiotic Food
Foods naturally rich in probiotics are another important fuel source for your microbiome. Yogurt, kefir, raw sauerkraut, miso and kimchi naturally contain some of the good bacteria your gut needs. When possible, look for a probiotic yogurt, as these will come with the most health benefits. Fermented foods also reduce inflammation, which improves the function of both your microbiome and immune system.
Prebiotic Food
While probiotics are the healthy gut bacteria themselves, prebiotics are the food for the probiotics. It’s important to consume enough prebiotics, since these will provide the fuel source needed for the microbiome to thrive. You can take a prebiotic supplement for extra support, but you can also find prebiotics naturally in certain foods. The best options include:
Bananas
Asparagus
Garlic
Lentils
Onions
Legumes
Chicory root
Leeks
Improve Immunity
If you notice yourself getting sick more frequently, or you’re at risk for an autoimmune disease, take a look at your gut health. By changing your diet and taking a probiotic supplement, you can enhance the diversity of your microbiome to keep the good bacteria thriving and the bad bacteria at bay. To develop a diet and lifestyle plan that works for you and your health concerns, meet with Dr. Pellegrino for a personal consultation.
Sources:
https://pubmed.ncbi.nlm.nih.gov/26757793/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3337124/
Written by Maggie Twaroski
Medically reviewed by Dr. Natalia Pellegrino