Focusing on the Inside: Gut Health


By O2X Nutrition Specialist Maria L. Urso, PhD

With so much emphasis on what we eat, the way we train, and how we look, it’s easy to neglect the things you cannot see or monitor. The human gut, at nine meters long with enough mass to cover an entire tennis court, deserves a lot more attention than it gets. This is because our guts house a massive community of bacteria. Our bodies and our guts rely on the make-up of that community of bacteria for optimal health. Creating and maintaining a rich and diverse gut microbiome can positively impact your metabolism, immune system, appetite, and mood. To do this, the goal is to reduce the amount of gut bacteria that favor unhealthy outcomes and increase the gut bacteria that promote healthy metabolic, immune, and hormone responses. 

As you navigate your health goals to achieve optimal performance, here are four tips to help diversify and improve your gut health. 

Tip 1: Kick the sugar imposters to the curb

Why: Erythritol and other artificial sweeteners have been getting a lot of press lately. In addition to the link between higher blood levels of Erythritol and a greater risk of heart attack or stroke, many studies have documented a disruption in the gut microbiome with the consumption of artificial sweeteners (including Stevia, although results are mixed). This imbalance may trigger glucose intolerance- essentially increasing the risk of diabetes and heart disease. Other studies have demonstrated that “unhealthy” gut bacteria prefer sugar alcohols as a source of sustenance and end up overpopulating healthy gut bacteria. Finally, there is evidence to suggest that artificial sweeteners increase the number of gut bacteria that are more efficient at pulling energy from our food and turning that energy into fat. 

How: Eliminate aspartame, sucralose, erythritol, stevia, saccharine, and other sugar alcohols. Read labels, as these sugar-like sweeteners are in many food supplement bars, zero/reduced calorie drinks (including sports drinks), protein powders, and other low-calorie foods. If you have become accustomed to these flavors in your diet, it may take some time. Attempt a gradual reduction in these foods each week, replacing them with nutritive sweeteners or full-calorie products.

Tip 2: Reduce your consumption of processed food

Why: High consumption of processed foods can change the gut microbiome and lead to an overabundance of unhealthy gut bacteria. Processed foods include pre-packaged, ready-to-eat, convenience foods and those with additives, emulsifiers, gums, and/or preservatives. When these foods alter the ratio of bacteria, it damages the protective mucosal layer of your gut. Continued damage to the mucosal layer is what leads to inflammation and immune system dysfunction. In the short term, this can lead to abdominal discomfort and bloating and increased susceptibility to cold and flu. Over the long term, this inflammation can lead to more serious conditions such as irritable bowel disease. Finally, since the nutrients in processed foods are not as bioavailable to the body and are more difficult to digest, there is a greater propensity for weight gain. 

How: Start to do a diet “clean out”. Do the foods you eat come from the ground (Plant) or have a face (Animal)? If so, you are on the right track. If they are in a package with an exhaustive list of ingredients (many that you do not recognize), try to minimize your consumption. Similar to the reduction in artificial sweeteners, do not try to do this all at once. Start with easy replacements, such as replacing salad dressing (highly processed) with a more nutrient-dense and gut-friendly substitute such as nuts, fruit, cheese, or salsa. 

Tip 3: Eat like a Tanzanian 

Why: Little did you know that there was a worldwide search for the people with the most diverse gut microbiomes. Well, the Hadza people of Tanzania won that award with gut microbiome diversity which is 40 percent higher than the average American. They have achieved this by eating a wide variety (>500 species) of plants and animals. This is in stark contrast to the meager 50 species consumed by most Americans. While the mechanism is not quite clear, this diverse gut microbiome is associated with a general lack of obesity, allergies, heart disease, and cancer. What is even more remarkable, these hunter-gatherers have changes in the diversity of their gut microbiome over the course of the year, depending on the season and what foods they are eating. During the dry season, when they are eating mostly meats, their gut bacteria look more like ours. Once they re-introduce fruits and vegetables back into their diets during the wet season, the bacterial diversity returns. This tells us that negative changes in the gut microbiome are reversible.

How: While there are several fad diets that have taken the internet by storm, the Mediterranean way of eating remains the timeless solution to achieving optimal gut microbiome diversity and stability. Increased consumption of vegetables, fruits, lean meats and fish, multi-grain carbohydrates, and healthy fats will favor gut health. Overall, the mechanism seems to be the higher consumption of dietary fiber. Fiber appears to feed the healthy gut bacteria, while lean sources of protein, versus their full-fat version, decrease the number of disruptive gut bacteria. Of note, individuals following a Ketogenic Diet (little to no vegetables or fruit) had changed to their gut microbiome diversity that could be detrimental, with obesity, type-2 diabetes, and depression highlighted as potential outcomes. 

Tip 4: Get moving

Why: Moderate exercise has been shown to impact not only the diversity of gut bacteria but to enhance certain bacteria that play roles in helping the body adapt to exercise, maintain healthy body weight, and reduce the risk for obesity-related conditions. Exercise also stimulates the bacteria that improve the overall health of the lining of the gastrointestinal tract- something that can protect against gastrointestinal illnesses and even colon cancer. In one study, scientists sampled the gut microbiomes of Boston Marathon Runners. After the marathon, they found an increase in one type of bacteria which the body uses to break down lactic acid. 

How: If you are currently exercising, continue to follow a plan that incorporates at least 150 minutes of moderate-intensity exercise each week. If you are not exercising, start. Be careful not to overdo it, as there have been several reports of negative alterations in gut microbiome diversity and function with extreme exercise. This is an individual response, so while it is not possible to prescribe what overexercising looks like, a good rule of thumb is to balance your extreme efforts or races with recovery time and moderate, less-taxing sessions. 

Achieving and maintaining a healthy and diverse gut microbiome should be a key focus in realizing your health and performance goals. Optimizing your gut microbiome can lead to improvements in your antioxidant defense system, body composition, nutrient absorption and use, bone health, sleep, immune function, and overall performance. As you continue to strive for those performance and aesthetic goals, do not forget to focus on what’s inside- it’s truly the best part of you. 


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