Popular Conditions & Diets
Gut health is a seriously hot topic right now. But what exactly do ‘gut health’ and the ‘gut microbiome’ refer to? Simply defined, gut health refers to the function of our entire digestive tract, the 9-meter long tube through which food passes, nutrients are absorbed, and waste gets eliminated. The gut microbiota refers to the microorganisms – including bacteria, yeasts, and parasites – that live along our digestive tract. The gut microbiome is slightly different and relates to the microbes and their genes. Although microbiota and microbiome often get used interchangeably.
Trillions of bacteria live in the lower part of our digestive tract (the large intestine) and play essential roles in our health. Gut bacteria are responsible for producing vitamins and hormones (including serotonin, the happy hormone), influencing our appetite and metabolism, and impacting our mental health through the gut-brain axis. Good gut health is linked to better immunity since the digestive tract contains 70% of our immune system. Good gut health is also associated with lowered risk of heart disease and diabetes.
Ultimately, a varied diet containing large amounts of plants is vital to good gut health. Microbes feed off different types of fibres (including prebiotics) and plant chemicals (phytochemicals). Aim for 30+ varieties of plants every week. Include foods from all six plant-based food groups: fruit, vegetables, legumes, whole grains, nuts, and seeds.
Fibre is the primary source of fuel for our gut bacteria. Human cells cannot digest dietary fibre; its sole purpose is to feed gut bacteria. Fibre increases the diversity and abundance of the gut microbiota. Official recommendations suggest a minimum of 25g/day for women and 38g/day for men. But I recommend aiming for 40-50 grams of fibre per day if you can tolerate it, as recommended by the well-established Mediterranean diet. Note: certain health conditions, including IBS and IBD (Crohn’s and Colitis), can make tolerating large quantities of fibre difficult. Speak to your physician or dietitian if you are concerned.
A diet high in processed foods and added sugars can decrease the number of good bacteria in your gut. This imbalance can cause increased sugar cravings, resulting in further damage to your gut health. Simply put, the goal should be for the majority of foods you eat to be whole foods. It’s a simple concept but difficult to put into practice. Life is busy, and convenience foods are everywhere! But the more food we eat in its natural state, without added chemicals, additives, and preservatives (not to mention the fat, salt, and sugar), the better. When you cook at home, you are the boss. You know exactly what goes into your food, and that is half the battle.
Probiotics: live microorganisms that provide a health benefit when administered in adequate amounts. = good bacteria that have health benefits
Prebiotics: fermentable ingredients that selectively improve the growth of beneficial gut bacteria = food for good bacteria
Probiotic supplements have been a major discussion point for years. However, clinical trials have demonstrated that while specific strains of probiotic supplements are beneficial in treating certain issues (i.e., IBS, antibiotic-associated diarrhea, etc.), probiotic supplements have not been proven helpful for the average healthy person. That’s not to say that probiotics aren’t positive, just that the scientific evidence hasn’t demonstrated a specific health benefit in the general population. Rather than taking a supplement, focus on increasing your gut bacteria through a diet high in prebiotics (food for good gut bacteria) and probiotic-containing fermented foods such as kefir, sauerkraut, and kimchi. Dietary fibres with demonstrated prebiotic effects include chicory, onion, artichoke, garlic, asparagus, bananas, tomatoes, barley, wheat, and rye.
Exercise may increase levels of several beneficial gut bacteria as well as the health-promoting short-chain fatty acid butyrate. Butyrate is associated with reduced inflammation and good gut health. Exercise has also been shown to promote higher gut microbiota diversity, a critical factor in overall gut health. As a general rule, aim for at least 30-minutes of low to moderate-intensity activity every day. This does not mean that you have to do intense, sweat-dripping, high-intensity workouts every day. A brisk walk is just fine!
A healthy gut essentially refers to a diverse and abundant microbiota. This means that we want more gut bacteria and a greater variety of them. As a Registered Dietitian with a passion for the gut, I work with clients to improve their gut health. The good news is, our environment plays a significant role in impacting the health of our gut, and our diet specifically has the most prominent role of all environmental factors in altering our gut bacteria. Therefore, making a few simple dietary changes can have a massive impact!
Although a grazing approach of eating small frequent meals may work for some, it may also promote overeating and digestive issues. Integrating periods without eating into your daily diet is vital to activate your migrating motor complex (MMC), which is an important mechanical function of our digestion. Consider a fasting period of at least 12-hours daily to stimulate your migrating motor complex. If unable to fast for at least 12-hours daily, consider leaving 4-5 hours between meals which will also assist in activating your MMC and improve digestion.
We know that eating high amounts of added sugar is associated with adverse health outcomes. With gut health, consuming high volumes of refined sugar can lead to reduced gut microbiota diversity (remember gut health = a diverse and abundant gut microbiota). High intake of added sugar has also been associated with increased gut permeability (or “leaky gut”), inflammation, and an overall decrease in good bacteria and increase in harmful bacteria.
There are good fats, and there are bad fats. Studies have linked omega-3 fatty acid intake with increased gut bacterial diversity and short-chain fatty acids (SCFAs) production. SCFAs are associated with playing a role in protection against bowel cancer, depression, and diabetes. Omega-3s also have powerful anti-inflammatory properties and play an essential role in heart health and brain function. Choose healthy fats such as olive oil, avocados, fatty fish, nuts, and seeds. Limit animal sources of saturated fat and fats high in omega-6 fatty acids (i.e., canola oil, sunflower, and soybean oil).
Did you know that gut bacteria help to metabolize alcohol? This is one of the reasons why we have different tolerances to alcohol. Greater amounts of healthy gut bacteria can help your body more efficiently detoxify it. However, excessive alcohol consumption can inhibit the production of digestion enzymes and secretions, leading to poor digestion and absorption of nutrients. Too much alcohol can cause inflammation in your gut, leading to increased gut permeability (“leaky gut”). Bonus - red wine contains health-promoting polyphenols, which our gut bacteria love. Enjoy in moderation!
The general concept of healthy eating isn’t that hard. It’s the commitment that’s hard. We are faced with hundreds of food choices every week, and we cannot possibly make the “right choice” every time. And obsession leads to negative thoughts, which can lead to unhappiness and bingeing. Food should not be a source of negativity. Food is awesome! Make the healthy choice whenever you can, but when you make less than ideal choices, choose to forgive yourself and move on.
