Our gut health significantly influences our overall health and well-being, yet this is a connection many often underestimate. The health of our gut is largely influenced by our dietary and lifestyle choices, making it crucial to understand how we can positively impact gut health with our daily choices. 

Keep reading to delve deeper into the important roles of the gut and what you can do to optimize gut health for greater overall well-being.

What is the gut?

When we are talking about the gut, we are referring to the entire digestive system extending from the mouth to the colon. Our gut, or gastrointestinal tract, has amazing capabilities that help to promote our physical and mental health and well-being. There is not a system of the body that the gut doesn’t influence! Our gut is important for digesting and absorbing our food and nutrients and it can even synthesize certain nutrients of its own. The gut can also synthesize neurotransmitters, our body’s chemical messengers, which influence mental health. Maintaining a healthy gut also plays an important role in the prevention and management of chronic diseases such as inflammatory bowel disease, obesity, autoimmune diseases, and heart disease.¹

The Gut Microbiome

The gut houses a vast community of trillions of microorganisms, as known as gut flora, in the large intestine that plays a critical role in shaping our physical health, mental health, and immune health.² We refer to this ecosystem as the gut microbiome. Ideally, we want to maintain a healthy balance of bacteria in the gut. Maintaining this balance is important for protecting the human body from the overgrowth of bad bacteria and other pathogens.

The Roles of the Gut & Gut Microbiome

Digestion & Absorption

The process of digestion starts with the chewing of our food which is further broken down by stomach acid and digestive enzymes released by the stomach and small intestines. Once the food reaches the large intestines, its microbes further aid in the digestion and absorption of our food. A healthy gut allows our body to optimally digest and absorb the food we are eating, allowing our body to utilize its nutrients. An unhealthy gut, on the other hand, can lead to health issues like nutrient deficiencies and poor digestion, contributing to poor overall gut health and uncomfortable symptoms such as indigestion, nausea, gas, and bloating.

Mental Wellbeing

The gut and brain are interconnected and influence each other bidirectionally.³ We refer to this connection as the gut-brain axis. Imbalances in the gut can influence our mood and brain function and vice versa. Chronic stress, for example, can contribute to poor digestion and overall poor gut health. The gut houses a complex network of nerves that we refer to as the enteric nervous system which controls the body’s digestive functions. We refer to this powerful network as the body’s ‘second brain.’ Additionally, the gut is responsible for synthesizing neurotransmitters, which influence mood, sleep, and appetite. It is estimated that about 95% of our body’s serotonin is made in the gut.³ 

Immune Health

Maintaining a balanced microbiome and a strong intestinal lining plays a huge role in promoting immune health. It is estimated that 80% or more of the immune system is housed in the gut!⁴ Our gut lining is one of the body’s first lines of defense, protecting it from potential threats such as toxins and viruses. Imbalances in the microbiome can contribute to inflammation and a weak intestinal lining, which can lead to poor immune function. 

Signs of Poor Gut Health

Poor gut health can manifest in various ways. Here are several common signs and symptoms that can indicate poor gut health:

• Symptoms of Irritable Bowel Syndrome, such as chronic constipation or diarrhea
• Frequent bloating and gas
• Abdominal pain or discomfort
• Nutrient deficiencies
• Food sensitivities
• Frequently getting sick
• Chronic fatigue
• Low mood
• Joint pain
• Acne
• Chronic bad breath

Promoting a Healthy Gut with Diet & Lifestyle

1. Consume a diet rich in colorful whole foods

To promote optimal gut health, prioritize a diet rich in whole foods such as fruits, vegetables, whole grains, legumes, nuts, and seeds, along with lean protein and healthy fats. These foods provide essential nutrients that support a healthy gut. A nutrient-poor diet, high in ultra-processed foods, saturated fat, and added sugar, on the other hand, lacks the essential nutrients needed to support a healthy gut. This dietary pattern can diminish the diversity and abundance of healthy gut microbes, causing gut issues. 

While it is okay to consume these foods in moderation, focusing on consuming whole foods is key. Ideally, we should aim to get a diverse range of whole food sources. Studies have shown that aiming to consume 30+ plants a week is ideal for promoting a healthier gut flora.⁵ Additionally, eating a variety of colorful foods, including red, orange, yellow, green, blue/purple, and white/brown, is beneficial. These colorful foods contain vitamins, minerals, and phytonutrients that support a healthy and diverse gut microbiome.

PRIORITIZE	REDUCE/IN MODERATION
Fruits: e.g., Blueberries, Banana, Strawberries, Melon, Papaya, Pineapple, Citrus Fruits	Refined Grains: e.g., White bread, White pasta
Vegetables: e.g., Broccoli, Sweet Potato, Asparagus, Artichoke, Onions, Carrots	Saturated Fat: e.g., Fatty cuts of meat, Butter, High Fat Dairy, Fried Food, High Fat Cheese
Whole Grains: e.g., Brown rice, Quinoa, Multigrain Bread, Corn	Sweets: e.g., Candy, Pastries, Ice Cream, Cookies, Artificial Sweeteners
Nuts: e.g., Cashews, Almonds, Walnuts, Hazelnuts	Processed Meats & Cheese: e.g.,Deli Meat, Sausage, American Cheese, Hot Dogs
Seeds: e.g., Sunflower seeds, Chia seeds, Hemp seeds, Pumpkin seeds
Lean Protein: e.g., Wild Caught Salmon, Eggs, Soybeans, Chickpeas, Chicken breast, Lean ground meat *It is possible to get sufficient protein from plant-based foods with a whole foods-rich diet!
Healthy Fats: e.g., Olive oil, Avocado, Wild Fatty Fish, Avocados, Walnuts

2. Increase fiber intake slowly

Whole foods are rich in fiber, also known as prebiotics, which have various health benefits, including promoting a healthy, robust microbiome. Fiber is consumed by certain beneficial microbes, including beneficial bacteria, allowing them to thrive and repopulate. Imagine our microbiome as a garden. Fiber is like the fertilizer which helps to feed the plants, or microbes, allowing them to grow. Furthermore, certain types of fiber can bulk the stool, promoting regularity. 

When increasing the intake of fiber-rich foods, it is important to increase intake slowly and hydrate! Doing so will allow our body to adjust to the dietary changes to avoid GI upset.

3. Consume probiotic-rich foods

Probiotics aren’t just found in probiotic supplements. They are in some of the foods we eat. These probiotics are live microbes that are found in fermented food products such as kefir, kombucha, yogurt, and miso. When we ingest probiotics, they can help replenish the gut microbiota. Think of probiotics as ‘seeds’ that will cultivate new microbes in our ‘microbiome garden.’

4. Chew food thoroughly

It is important to chew our food all the way when eating. Chewing food thoroughly improves digestion as it allows our gut to optimally break down our food and absorb nutrients. 

5. Try to eat without distractions

When eating, it is important to focus only on eating, minimizing distractions. Doing so will signal to the body that it’s time to eat. This will trigger the digestive process by initiating the release of digestive enzymes and stomach acid, aiding in the breakdown of our food.

6. Get regular movement

Regular exercise has been shown to positively impact the diversity and abundance of good bacteria in the gut.⁶ Additionally, physical activity can help stimulate the muscles in our digestive system, aiding in the movement of food and waste through the gut. Therefore, we have good reason to incorporate regular physical activity into our daily routine as it can be beneficial for maintaining optimal gut health.

7. Keep stress in check

Stress can significantly impact our gut health due to the strong connection between the gut and the brain. To support gut health and overall well-being, it’s essential to reduce stress and engage in regular stress reduction techniques. Practices like meditation, yoga, and breathwork can help calm the mind, reduce stress levels, and promote relaxation. These techniques can also help improve digestion by reducing tension in the digestive tract and supporting the gut-brain connection. 

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References

1: Vijay, A., Valdes, A.M. Role of the gut microbiome in chronic diseases: a narrative review. Eur J Clin Nutr 76, 489–501 (2022). https://doi.org/10.1038/s41430-021-00991-6

2: Ursell, L.K., et al. Defining the Human Microbiome. Nutr Rev. 2012 Aug; 70(Suppl 1): S38–S44.

3: Appleton J. The Gut-Brain Axis: Influence of Microbiota on Mood and Mental Health. Integr Med (Encinitas). 2018;17(4):28-32.

4: Wiertsema SP, van Bergenhenegouwen J, Garssen J, Knippels LMJ. The Interplay between the Gut Microbiome and the Immune System in the Context of Infectious Diseases throughout Life and the Role of Nutrition in Optimizing Treatment Strategies. Nutrients. 2021;13(3):886. Published 2021 Mar 9. doi:10.3390/nu13030886

5: McDonald D, Hyde E, Debelius JW, et al. American Gut: an Open Platform for Citizen Science Microbiome Research. mSystems. 2018;3(3):e00031-18. Published 2018 May 15. doi:10.1128/mSystems.00031-18

6: Boytar AN, Skinner TL, Wallen RE, Jenkins DG, Dekker Nitert M. The Effect of Exercise Prescription on the Human Gut Microbiota and Comparison between Clinical and Apparently Healthy Populations: A Systematic Review. Nutrients. 2023;15(6):1534. Published 2023 Mar 22. doi:10.3390/nu15061534