The Best Diet for a Healthy Gut

“Gut health” has remained a hot topic in the health and wellness space in the past decade. In 2012, The Human Microbiome Project revealed groundbreaking research into the bacterial ecosystem that exists inside of human beings. Scientists discovered more about intestinal diseases, the relationship of the gut-brain axis, and how the composition of our gut bacteria influence health outcomes in the mid-2010s than ever before. This research project opened a window into the complexity of the human body. We now know the connection between gut health and mental health, cancer, metabolic disease, food allergies and intolerances, autoimmune conditions, digestive issues, skin health, and so much more. 

Since 2017, social media and wellness influencers have exploded the consumer interest and demand for information on how to optimize gut health. You may recognize some products that have emerged since then like; coconut cult yogurt, food sensitivity tests, sea moss, probiotics, seed oil free diets, fiber-maxxing, fermented foods, and so on that have been advertised as “gut healthy”. With conflicting advice and forever changing trends, the question remains, what is really the best way to improve your gut health? We read through all the research, so you don’t have to, and put together the best diet for a healthy gut. So, let’s skip over the trendy fad diets and supplements and get right down to the science! 

Let’s first start by educating our readers a little more about what the “gut” is. Our gut is a microbiome, which is a system of microorganisms (bacteria, fungi, viruses) that interact to regulate our immunity, digestion, and metabolism. Our microbiome, which primarily lives in the large intestine of the gastrointestinal tract, is constantly changing. It is heavily influenced by diet, exercise, stress, medication, environment, and illnesses. A healthy gut microbiome is characterized by a diversified community of bacteria, as each bacteria plays a role in keeping the host, you, healthy.  Dysbiosis, on the other hand, is reduced diversity and changes to the composition of the gut microbiota. Dysbiosis is associated with obesity, diabetes, and gastrointestinal diseases such as irritable bowel disease (IBD).  

So, how can we keep the gut happy and prevent dysbiosis? Short-chain fatty acids (SCFAs) are known to play a crucial role in keeping our gut healthy. SCFAs are produced by indigestible carbohydrates, also known as dietary fiber. Diet influences the diversity, composition, and function of the gut microbiome. Your diet either helps maintain, or disrupts, the homeostasis in this delicate environment. A diet balanced with adequate carbohydrates rich in fiber, protein, and healthy fats is critical for maintaining a strong intestinal barrier, immune tolerance, and flourishing bacteria. Alternatively, an unbalanced diet high in ultra-processed foods, fried foods, alcohol, and other irritants can lead to leaky gut and chronic inflammation, as seen in IBD. 

Leaky gut is when the barrier of the intestinal wall is compromised, allowing food particles and toxins to cross the barrier into our bloodstream, causing inflammation. The permeability of this intestinal barrier is highly regulated by the bacteria in our gut. Commensal bacteria, or our good gut bugs, help maintain a strong barrier by forming SCFAs and microbiota that are resistant to pathogens. Diets high in saturated fats, sugar, and emulsifiers impair the intestinal barrier by increasing the bacteria, like Akkermansia muciniphila, which thins out the lining of the intestinal wall. While Akkermansia muciniphila can be a beneficial bacteria in moderate amounts, an overgrowth of this bacteria can degrade the protective gut mucin layer which impairs the function of our intestinal barrier. This can be aggravating in inflammatory diseases such as irritable bowel disease. A diet rich in fermented foods can help prevent this from happening, by increasing the diversity of good gut bugs and driving down markers of inflammation. Some fermented foods that help our gut stay strong and healthy are; yogurt, kimchi, sauerkraut, kombucha, tempeh, miso, and kefir. 

Our best chance for keeping our gut healthy is increasing our diversity of fiber rich foods. Studies have shown that low fiber diets, even when high protein, is the main contributing factor to the reduced gut microbiota diversity. Some studies show that changes in the microbiome can happen in as little as one day! Dietary fiber is the key for maintaining and improving our gut microbiota to reduce our risk of inflammatory diseases such as obesity, diabetes, and IBD. Increasing dietary fiber can even help put IBD, specifically Crohn's disease, in remission. It is important to note that fructans, a type of fermentable carbohydrate, can worsen gut symptoms, which is why you may have heard of the low FODMAP diet or reducing fiber to relieve GI distress in those with IBD or IBS. While restricting FODMAPs can relieve symptoms, it is not a long term solution, nor a cure. Please work closely with a dietitian if you are on a low FODMAP diet to help you reintroduce these foods into your diet. 

So, our suggestion for the healthiest diet? Focus on addition, rather than restriction. Your gut thrives with a diversity of plant based foods that are rich in fiber to maintain homeostasis in our gut. Introduce one new plant based food in your diet every week. Focus on fruits, vegetables, and grains. You may have heard before that the Mediterranean diet is the healthiest diet. This is likely because the mediterranean diet is characterized by a high intake of fruits and vegetables, whole-grain cereals, poultry and fish, which promotes diversity and richness of the gut microbiota due to the high fiber content and anti-inflammatory properties of these foods. We recommend aiming for 4 cups of vegetables and 3 cups of fruit per day while incorporating whole grain at each meal! Using the research backed best practices for diversifying your gut microbiota, we created a grocery list to help you increase your intake of fiber rich foods to support your gut health journey! We recommend choosing one new food per week, or every other week, to start. 

If you are already experiencing gut issues or have trouble tolerating dietary fiber, reach out to our team! We are here to help you on your gut health journey, because we know diversity in the diet is the key to long term health and success. If you can tolerate these foods just fine but feel overwhelmed in the kitchen, purchase our SkimBites recipes for ideas on how to incorporate these new foods into your diet with simple and easy meals. 

Resources:

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Gopalakrishnan V, Helmink BA, Spencer CN, Reuben A, Wargo JA. The Influence of the Gut Microbiome on Cancer, Immunity, and Cancer Immunotherapy. Cancer Cell. 2018 Apr 9;33(4):570-580. doi: 10.1016/j.ccell.2018.03.015. PMID: 29634945; PMCID: PMC6529202.

Peirce JM, Alviña K. The role of inflammation and the gut microbiome in depression and anxiety. J Neurosci Res. 2019 Oct;97(10):1223-1241. doi: 10.1002/jnr.24476. Epub 2019 May 29. PMID: 31144383.

Zhang P. Influence of Foods and Nutrition on the Gut Microbiome and Implications for Intestinal Health. Int J Mol Sci. 2022 Aug 24;23(17):9588. doi: 10.3390/ijms23179588. PMID: 36076980; PMCID: PMC9455721.