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Gut Check: What You Need To Know About Gut Health

Why looking after your gut has never been so important.

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Gut health is critical to our overall health and wellbeing—and it’s something we hear an increasing amount about—but what is it and why should we care about it? For many people, especially athletes, it’s something we learn about when we have to, that is, when something isn’t working as it should. It’s often at this stage that we realize just how far-reaching gut health can be to our overall health and how looking after your gut can lead to much more than just better digestive health, but also factors such as better sleep, increased energy, and less aches and pains, which is something that, as athletes, we all welcome. We spoke to three experts and underwent a gut test in order to find out more. 

What Is Gut Health?

Dr. Kiki Silver is a medical doctor who specializes in functional and integrative medicine and has helped many endurance athletes resolve issues relating to gut health. She said gut health typically refers to the steps involved in proper digestion and absorption—from the moment we take a bite of food or sip a drink all the way through until “bowel elimination.” There are many parts of this complex process that can go wrong and it’s then we will feel the effects. Patrick B. Wilson, author of The Athlete’s Gut and a professor of exercise science and registered dietitian, said: “The gut has many different functions that are critical to health. Most obviously, it breaks down and absorbs food and nutrients we eat. If it fails to achieve this most critical function, significant nutrient deficiencies and health issues will undoubtedly arise.” 

Our gut is a site of immune activity and defense, Wilson said, continuing: “You literally have trillions of microorganisms living in your gut, and although many of them are health-promoting, some are not. A lack of the right kind or quantity of certain bacteria in the gut (primarily in the colon) is hypothesized to contribute to a wide array of diseases.”

Indeed, sports nutritionist and exercise physiologist Dr. Stacy Sims said that the key to good gut health is keeping the right balance of bacteria. “The gut is tightly tied to our immune system, moods, cardiovascular and metabolic health, digestive health, and even weight control,” she said. “Diversity of the gut microbiome is key.”

The gut is tightly tied to our immune system, moods, cardiovascular and metabolic health, digestive health, and even weight control.

When Good Guts Go Bad

Oftentimes, problems with gut health present as digestive issues—bloating, constipation, heartburn, gas, diarrhea, or nausea—but they can also arise in less obvious ways, such as skin irritations, poor sleep, sudden weight changes, or cravings. While the former might lead you to think something is clearly wrong with your digestive health, the latter are definitely less obvious. As Wilson said: “There are just so many different possibilities that it really requires the experience of a trained clinician to figure these things out. If symptoms are only periodic or mild in nature then you could try journaling or documenting what you ate to see if there are foods that consistently provoke issues. You should also be mindful as to whether stress and anxiety precede any gut issues, as we know from research that there is a consistent connection between those feelings/emotions and GI issues.”

Testing, Testing

It is here that a medical doctor, such as Silver, who uses a blend of Western medicine and functional medicine, can truly come into her own. She likens figuring out what the root cause of poor gut health might be to “detective work,” taking the many parts of a puzzle to track and trace what is happening in your body.

Initial testing can be as straightforward as taking a patient’s history, doing an exam, and running standard laboratory and/or stool tests, imaging analysis, or even scopes (endoscopies, colonoscopies). Of course, a lot can depend on the signs and symptoms that a patient is experiencing, but these will guide what form testing takes at the outset.

Sims highly recommends getting a microbiome test from a company such as Microba that uses shotgun metagenomic sequencing, stating: “This not only tells you what bacteria is present, but because it is DNA sequencing, it tells you the effect the bacteria have on your body.”

There are a myriad of other tests out there too, some of which use DNA sequencing, some test fecal matter, while others test blood samples. We took a gut microbiome test using a test kit from Ixcela, which involved a relatively straightforward at-home pinprick blood test that you mail to a laboratory and your results are returned to you within a week or so.

The Ixcela test looks at 11 metabolites, which are markers of health, wellness, and disease risk and progression. Rachel Stuck, nutritionist at Ixcela, said: “All 11 metabolites are related to the gut microbiome in some way—they are either secreted by specific types of bacteria in the gut, are molecules that are regulated by the gut, or are metabolites that indicate the output and functionality of the gut. Many of them are critical because the body converts them into other needed substances, e.g. tryptophan is eventually converted into melatonin, which is important for sleep.”

Your report from Ixcela gives you results across five different categories: Gastrointestinal Fitness, Emotional Balance, Cognitive Acuity, Energetic Efficiency, and Immuno Fitness.

Stuck said: “While your overall results are very good, we would recommend two changes to your diet and lifestyle to help improve your scores. Firstly, consider reducing caffeine intake as excessive caffeine intake contributes to the high metabolites of Xanthine and 3-methylxanthine we see in your results. When these metabolites become elevated it leads to inflammation and can further disrupt the microbiome. Secondly, consider including mindfulness and mediation in the evening to support the rest and digest response of the body.”

In addition to the diet/lifestyle changes, there are also a host of foods that Stuck recommends you include in your diet as well as other steps to take, which in this case included more Vitamin C-rich foods, ensuring adequate water intake each day, including more fiber-rich foods, such as kale, jicama, and steel cut oats, as well as making sure to increase your carbohydrate intake when energy expenditure goes up.

Some experts, however, suggest tests such as Ixcela’s are only “two dimensional” and warn not to place too much importance on their results. Sims said: “These types of tests (pinprick of blood) just test residual metabolites; it does not tell you the actions of the bacteria that do not produce metabolites that circulate freely. With just an assay of blood or fecal matter you are only getting a 2D picture of what is happening.”

Wilson concurs, adding: “To be 100% clear, we do not have good science that tells us how to practically manipulate an athlete’s microbiome to improve their fitness or performance.”

Fixing Your Gut Health

When it comes to “fixing” your gut health, Wilson said a lot obviously depends on what is causing the problem and that there is no “one-size fits all” approach. He said: “This was part of my motivation for writing The Athlete’s Gut. It covers all of the symptoms that are commonly reported by athletes and some of the potential solutions for each.”

Sims said it can be easy to look for an over-the-counter (OTC) probiotic or complicated medical intervention, when in actual fact simple, whole foods can be the best solution. “We can get so many prebiotics and probiotics that we need from the food we eat. OTC probiotics do not help. They only affect the upper part of the intestines, the bacteria that has the least, if any, systemic effect. Prebiotic fiber is food for the deep gut bacteria, which is another reason why veggies and fruits are so important to health. The larger the diversity of the gut bacteria, the better our health. In short, lots of fresh whole foods is the best fix!”


If you are struggling—or have been struggling—with digestive issues or symptoms that you feel could be gut-related, it is well worth beginning the investigative work needed to understand the root causes of the problems. Ensuring your diet is packed full of nutrient-dense foods is a vital first step, as this will help diversify your gut bacteria. Depending on the severity of your symptoms, you might be able to embark on this investigative work yourself or with the help of a straightforward test kit such as Ixcela’s, but understand there can be shortcomings and you can sometimes get lost in the labyrinth of information that’s now out there relating to gut health and testing. Should your symptoms be more severe or if you’re just unsure whether your issues are, in fact, gut related then it’s at that juncture it’s well worth leaning upon a trained clinician for greater input, expertise, and guidance. Although there is already a huge amount of data and research relating to gut health and its impact on our overall health, many experts believe we are only just scratching the surface on this topic and in years to come we will have a far greater understanding of just how important our gut is to every single part of our physical and emotional well-being.