Updated: Oct 26
By Ashley Powell, Registered Holistic Nutritionist
“Gut microbiome” is a term that we hear about often in the health and nutrition space these days, but what does it really mean? It refers to the vast array of microorganisms that live inside of us – ideally, in balance and with purpose. They reside in our digestive systems, primarily in our large intestine and colon. Compared to the 10 trillion cells that make up a human body, our gut microbiome is composed of 10 times that number… 100 trillion bacterial cells!
So what do these prolific gut bacteria do, exactly? They have a wide range of functions and play contributing roles in our immune defences, metabolism and mood, to name a few. It’s important to note that you don’t have to necessarily have typical gastrointestinal symptoms (i.e. gas, bloating, constipation, diarrhea) to have gut “problems” or imbalances.
Some other links between gut microbiome and health include:
Optimal Sleep – the health and proper balance of gut bacteria levels is critical for healthy melatonin levels
Weight Loss & Craving Management – governed by the short chain fatty acids that gut bacteria produce when they encounter and feed on specific foods
Brain Health – the gut is known as the 2nd brain; when the ratio of good to bad bacteria is out of balance, such mental health issues as anxiety, depression and brain fog can result
“You are what you eat” could be more accurately stated as “you are what your gut bacteria eat”. This is how critical their role is! So… how should we eat to best support gut health?
The single greatest predictor of a healthy and vibrant gut microbiome is the DIVERSITY of plants you consume. Ideally, we should aim to be incorporating at least 30 different plant species in our diets each week. This can be done regardless of what type of eating style you adhere to – keto, paleo, vegan, vegetarian or omnivore.
Why are plants so good for our gut? The fibre found in plants is critical, specifically the “prebiotic” fibre that plants provide. Commensal (“good”) gut microbes thrive by feeding on prebiotic fibre which they convert to post-biotic short chain fatty acids (SCFAs). While prebiotic fibre supports a healthy gut microbiome it also has other benefits. The healing power of short chain fatty acids is immense and includes:
Lowering total and LDL cholesterol
Regulating blood sugar
Optimizing thyroid health
Preventing autoimmune disease
Offer antioxidant and anti-inflammatory effects
In short, a wider variety of plant foods in your diet results in a stronger and healthier gut and thereby a stronger and healthier body! At each meal, think about how you can add more plant foods. Here are some ideas:
Add nuts, seeds and berries to your smoothie, smoothie bowl or yogurt parfait. For example, a smoothie bowl made with coconut milk, frozen cherries, banana, spinach, cacao powder and topped with granola (oats, almonds, pumpkin seeds, sunflower seeds and coconut flakes) and raspberries contains at least 11 different plant foods.
Add extra plant foods to your salad. To a bed of mixed greens and your chosen animal-based or plant-based protein source, add roasted sweet potato, steamed cauliflower, tahini (sesame seed paste) dressing, toasted pumpkin seeds, hemp seeds and diced avocado. This meal would contain at least 8 different plant species.
A hearty vegetarian or meat-based chili can be a great way to get in a ton of plant foods… onion, peppers, garlic, tomatoes, black beans, kidney beans, chickpeas, cannellini beans and a variety of spices and fresh herbs (chili powder, cumin, oregano, cilantro) are all great additions. Top with diced green onion and avocado and you’ve created a diverse serving of plants for your gut – more than a dozen different plant varieties.
Strive to diversify the number of plants you eat each week and help your gut microbiome achieve better balance and health – your body will thank you!