Inside the Toronto Functional Medicine Centre, patients can gain valuable insight on their digestive issues. Did you know that certain common food ingredients can negatively impact your gut health—and that the state of your gut health status  can influence other body systems? We clarify true or false statements below for educational purposes. 

True or False: Gut health treatments work the same for everyone.

False: A treatment for one patient may not have the same impact on another person. This is because each individual has a unique microbiome. The various types of microbes in your gut (both “good” and “bad” bacteria) are based on your current diet, medication use, environment, lifestyle factors, and age. 

Genetics can also establish the state of your microbiome, which is why comparing gut treatments between patients is not ideal. “Although gut microbiomes can differ markedly in diversity across adults, family members are often observed to have more similar microbiotas than unrelated individuals,” explains a Cell report. But this doesn’t mean that one gut solution will solve a whole family’s digestive issues!

According to the functional medicine model, treating the gut includes unraveling the root of current symptoms. For example, bloating, chronic inflammation symptoms, and indigestion can be caused by food sensitivities – this would require an individualized approach to wellness, as these sensitivities vary between people. 

If you were to visit a functional medicine practitioner, they would likely discuss your personal factors (i.e. your daily diet, exercise regime, etc.) to understand your gut and current health status. Lab tests would also be advised to scrutinize the microbiome, which can help health providers identify what needs to be “fixed” in your gut. After understanding your uniqueness and test results, a personalized treatment can be drafted for your digestion needs. 

True or False: You only need probiotics to heal your gut. 

False: If you’re considering probiotics, you should know that they contribute to optimizing digestion when they’re united with other health strategies. There is no such thing as a quick-fix or single supplement to reset your gut. Studies show that, along with supplements (i.e. pre- and probiotics) and diet, lifestyle factors indeed influence digestive health. For example, “Smoking and lack of exercise can significantly impact the large bowel (and potentially the microbiota) as they are risk factors for [colorectal cancer],” explains a Nutrients article. 

Even environmental factors from international traveling can affect gut bacteria, as you can boost your chances of getting or spreading infections linked to diarrhea. If travel-related illnesses are not treated, they may transition into chronic digestive concerns, such as irritable bowel syndrome. 

Overall, enhancing gut function requires a combination of tactics that may include:

• • Eating fibre-rich foods. 
  • Reducing your intake of sugary, ultra-processed options. 
  • Supplementation, such as pre- and probiotics. 
  • Regular exercise.
  • Stress management strategies, such as mindfulness, meditation, yoga, etc.
  • Alleviating nutritional deficiencies (to help modulate nutrient absorption and improve immune function).
  • Cutting down the use of unnecessary substances, such as smoking, alcohol, etc.
  • Addressing your current disease conditions (i.e. IBS, colitis, Crohn’s disease, etc.) with formal health interventions. 

Functional medicine testing is valuable for taking the guesswork out of what exactly needs to be improved in your gut, such as which bacteria to increase or decrease. These results can help a functional medicine provider tailor recommendations to your needs, such as the appropriate probiotic dosage and which foods to eliminate or incorporate into your diet.

True or False: Artificial sweeteners can harm your gut.

True: Though artificial sweeteners are common sugar substitutes for diabetes and weight management, they can negatively affect gut composition and your long-term health. “The consumption of unhealthy diets that are high in saturated fat and refined sugar and a lack of physical activity has been associated with dysbiosis of the gut microbiota, leading to inadequate glycemic control,” states a Nutrients article. 

Some non-nutritive sweeteners, such as aspartame, saccharin, and sucralose, have been associated with microbial imbalances and may contribute to gastrointestinal issues. Highly processed stevia blends may also alter gut composition, though pure stevia extract is often better tolerated.

These are categorized as non-nutritive sweeteners (NNSs). They do not offer the body glycemic effects because they have nominal amounts of or lack carbohydrates. In fact, the digestive system cannot digest NNSs, as artificial sweeteners are not structured the same as other foods. According to the Canadian Society of Intestinal Research, “…artificial sweeteners remain intact as they travel through the upper digestive tract, and then when they encounter bacteria in the colon, they exert an effect.” NNSs end up increasing and decreasing amounts of gut microbes, which may stimulate glucose intolerance. 

So, what about other sugar substitutes? Do you need to avoid all types of sweeteners? In practice, the answer varies for each individual, as everyone has a unique microbiome and health profile. It’s advised to speak to a functional medicine practitioner (i.e. holistic nutritionist, naturopathic medicine doctor) to get tailored health advice for your unique needs; this tip is especially beneficial if you’re struggling with insulin resistance, diabetes, blood pressure regulation, and cardiovascular conditions. 

However, other natural sugar alternatives are available at your local grocery or health foods store. Some examples include: 

• • Monk fruit
  • Yacon syrup

True or False: Gut issues have no relation to skin conditions.  

False: Though the skin and gut are different body parts, there’s a bridge connecting the two. As reported in a Frontiers in Microbiology article, studies have shown that the “…gut microbiome plays critical roles in modulating the development of diseases beyond the gastrointestinal tract, including skin disorders such as psoriasis.”

Scientists have coined this the gut-skin axis, and there are several conjectures of how this operates in the body. For example, it’s been thought that certain gut microbes can influence bodily functions (i.e. immune function); Faecalibacterium prausnitzii is one type of bacteria that can affect immunity, while boasting anti-inflammatory functions. According to an article from Biomedicines, when the body has low amounts of Faecalibacterium prausnitzii, heightened inflammation can ensue and exacerbate skin conditions, including psoriasis and acne. 

It’s also postulated that the integrity of the gut barrier can potentially affect skin conditions. This protects stomach contents from circulating throughout the body; thus, what you eat is important for nourishing the gut, as some foods (i.e. ultra processed items) can damage the intestinal barrier. When gut contents enter your bloodstream due to a dysfunctional barrier, this can impede skin health. 

This is why some functional health providers may add probiotic-rich foods or supplements for skin health goals. For instance, probiotics with the species Lactobacillus may be advised for helping manage atopic dermatitis. It was shown in one study that taking Lactobacillus brevis supplements for three months led to improvements to skin hydration. 

Overall, knowing this link between the gut and skin may affect treatments for some skin disorders. Further research is needed on the gut-skin axis, but so far, targeting skin health concerns via the gut has demonstrated promising effects.  

True or False: Digestion changes as you age.

True: It’s actually common to experience stomach issues with aging. In fact, “… though it does not affect the digestive system the same way it does other organs in the body, [aging] is a risk factor for some issues, including colon cancer, acid reflux, stomach sensitivity to medications and a decreased absorption of some vitamins,” explains the University of Michigan. 

Stomach acids protect the stomach from harsh agents. But with aging, the stomach starts reducing acid production; this results in the body needing additional time to digest food, forcing remaining acids to sit in the stomach for a lengthy time. 

Muscle contractions in the digestive tract can also weaken with age. These contractions are needed to force food through the tract; but when these muscles are worn down, they can cause food to trudge slowly through the colon. This long-winded process can cause the body to absorb liquid from leftover food, triggering constipation.

Thus, some digestive issues that may come with aging include: 

• • GERD (Gastrointestinal reflux disease)
  • Polyps
  • Constipation
  • Non-alcoholic fatty liver disease
  • Ulcers

If you’re on medications, please discuss digestive concerns with a functional medicine doctor, as some medications (i.e. calcium channel blockers) can cause side effects (i.e. constipation). In the meantime, healthy habits can be practiced at home to prevent indigestion. These may include: consuming high-fibre food, ideal hydrating and reducing your dairy intake, regular physical activity, and taking probiotics. 

True or False: You must stick to a gluten-free diet to improve gut health.

False.
Eliminating gluten is not necessary for everyone. According to the Harvard T.H. Chan School of Public Health, “gluten is a problem only for those who react negatively to it, or test positive for celiac disease. Most people can and have eaten gluten most of their lives, without any adverse side effects.”

While gluten contains a prebiotic compound called arabinoxylan oligosaccharide—which can support beneficial gut bacteria such as Bifidobacteria—it is not universally beneficial for gut health. In individuals with underlying gastrointestinal conditions, gluten may contribute to inflammation, increased intestinal permeability (“leaky gut”), and microbiome imbalances.

For those with celiac disease, non-celiac gluten sensitivity, inflammatory bowel disease (IBD), or irritable bowel syndrome (IBS), gluten can worsen symptoms by triggering immune responses and disrupting the gut lining.

Bottom line: Although gluten has some prebiotic value, its potential to promote inflammation may outweigh its benefits in sensitive individuals. If you have gut-related disorders or are prone to food sensitivities, a gluten-free diet may be more supportive of your gut health.

True or False: The gut-brain connection is just a theory.

False: Have you ever had a “gut feeling” about a situation? Or maybe you had “butterflies in your stomach”? Well, scientists have confirmed that the gut-brain link does exist, and this connection occurs through the enteric nervous system (ENS). 

The ENS is a body system with over 500 million nerve cells sprinkled along the GI tract. The ENS passes messages, neurotransmitters and hormones between your brain and gut, and this path is the gut-brain axis. Though the ENS is disparate from the gut, your microbiome contributes to controlling this axis. It’s been postulated that the gut-brain axis may have a role in regulating body functions, including mood, cognitive function, pain levels, immune function, hunger/satiety, and even your favorite foods! Studies suggest that the state of the gut-brain axis may be linked to a range of conditions, including:

• • Chronic fatigue syndrome 
  • Obesity
  • Autism spectrum disorder
  • Multiple sclerosis
  • Infantile colic
  • Digestive symptoms such as constipation and diarrhea

Therefore, it’s important to consider gut and brain elements for recuperating a poor gut. This may include a personalized treatment plan that targets stress and nutrition. Some tips to consider include: 

• • Reducing stress and anxiety: Find ways to manage daily tensions, such as knitting, painting, jogging, acupuncture, or mindfulness. A functional holistic nutritionist or psychotherapist may be of assistance. 

• • Getting organized: Tracking your schedule with an organizer can reduce stress and prevent “last-minute” tasks. 

• • Boosting your intake of various whole foods: Unlike ultra-processed foods (UPFs), whole foods can support beneficial effects in the microbiome. 
  • Consume both pre- and probiotics: These can be eaten via fermented foods (i.e. Greek yogurt) or you can take oral supplements.  

True or False: Not everyone has to “poop” every day.

True: Surprisingly, not everyone needs to “go” on a daily basis! But on average, the trend is that people poop three times daily or weekly. If you’re pooping over three times every day, this may be linked to diarrhea; bowel movements that happen less than three times a week may be related to constipation. Keep in mind though, “…there must be other symptoms present before the stool strictly qualifies as either diarrhea or constipation,” explains the Canadian Society of Intestinal Research.

Bowel movements are individualistic and, as per the functional medicine model, “pooping” concerns shouldn’t be compared to other groups or people. After all, poop consistency, color, and frequency are based on what you eat, medications, the supplements you consume, and any chronic disease/symptoms (medical history). Your pooping schedule is also based on these factors: 

• • How much fluids you consume:  Some people don’t drink enough fluids throughout the day. Hydration levels especially vary if you’re physically active and/or don’t eat enough fruits and vegetables.

• • Physical activity: Exercise can help keep you regular, but physical activity levels are different between sedentary individuals and athletes. 

• • Comfort levels: Constipation may form if you frequently “hold it in”.

• • Hormone levels: Studies show that the number of daily bowel movements can be caused by menstrual cycles.
  • Age: Older adults may be on medications that can cause diarrhea or constipation; also, the digestive system may change due to aging.

If you’re worried about how often you poop, the functional medicine approach to health is advised, as pertinent lab tests can be recommended. 

True or False: Coffee can offer benefits to your gut health.

True: A moderate amount of coffee can support gastrointestinal functions; but if you drink it excessively, too much can potentially cause anxiety, heartburn, and insomnia.

Science journals have described that consuming up to three cups of coffee per day does not appear to harm the digestive tract in most healthy individuals. In fact, coffee may support gut health in the following ways:

May relieve constipation:
A review in Nutrients notes that coffee stimulates intestinal motility and reduces transit time, which may help relieve constipation in some individuals. This effect is partly due to caffeine and other bioactive compounds that stimulate the enteric nervous system.

May boost “good” bacteria:
Coffee contains several compounds, particularly polyphenols, that can act as prebiotics, supporting the growth of beneficial gut bacteria such as Bifidobacteria. Some studies suggest that regular coffee consumption may positively influence microbiota composition and help reduce gastrointestinal inflammation, although more research is needed to fully understand these effects.

Provides fiber for healthy digestion:
According to Scientific American, brewed coffee contains small amounts of soluble fiber, such as polysaccharides, which can contribute modestly to digestive health. This type of fiber helps support gut bacteria and may assist in cholesterol regulation. However, coffee is not a major source of dietary fiber, especially compared to whole plant foods like oats, fruits, or legumes.

If you’re wondering which type of coffee to choose, dark roasts may be a better option for some people. Research has shown that dark-roasted coffee contains higher levels of a compound called N-methylpyridinium, which may help reduce the production of stomach acid. It may reduce gastric mucosal response, inhibiting gastric acid secretion. It likely affects gastric mucosal response. As a result, dark roasts may be less irritating to the digestive tract and better tolerated by individuals prone to acid reflux or stomach sensitivity.

However, the benefits can be offset by what you add to your coffee. Adding creamers, artificial sweeteners, or refined sugars may negatively impact the gut microbiome, potentially promoting inflammation or microbial imbalance. Additionally, for those with lactose intolerance, adding dairy can lead to bloating, cramps, or other digestive symptoms.

Bottom line: It’s wise to be mindful of what goes into your coffee. Choosing a darker roast and minimizing additives may help support digestive comfort and gut health.

True or False: Exercise does not have a role in gut function.

False: If you’ve altered your diet and have been taking probiotics, are you still having stomach discomforts? Then try a new exercise! 

According to an Oxidative Medicine and Cellular Longevity paper, “Recent studies suggest that exercise can enhance … beneficial microbial species, enrich the microflora diversity, and improve the development of commensal bacteria.” 

There’s no need to buy a gym membership, especially if you’re exercising for the first time. You can increase aerobic activities with daily walking, cycling, jump-rope, or jogging. Keep in mind though, a one-time workout will not suffice – the key is to maintain a long-term exercise regime to help sustain gut function. “Just like you’ll lose your stamina if you quit running for a few weeks, your gut microbiome will lose out on the production of good microbes once you stop exercising,” warns Everyday Health. 

The link between exercise and gut health has been researched. In 2017, one study analyzed women between the ages of 18-40, and it was shown that physical activity enhanced their microbiome composition. “The women who exercised had higher levels of health-promoting bacteria (like Roseburia hominis and Akkermansia muciniphila),” concluded Everyday Health.

Though physical activity can impact digestion, we want to gently remind you that exercise is not a stand-alone gut treatment. It should be combined with healthy eating, functional medicine therapies, and other lifestyle modifications. And if you have a respiratory condition, please consult with your doctor regarding physical activities. 

Suggested reading: An Introduction to Açaí with Functional Medicine from Toronto

Takeaways

• • Gut health is individualistic due to environmental and lifestyle factors, diet, use of medications, and age. A solution for one patient may not have the same effect for another person.
  • A comprehensive approach should be taken to heal the gut. Probiotics contribute to gut improvements; they are not a single solution for digestion improvements. Optimizing your gut includes modifying your lifestyle, increasing fibre and decreasing UPFs, managing stress levels, and exercising. 
  • Some sugar substitutes, such as aspartame, stevia, and sucralose, can be harmful to gut composition. Honey and monk fruit are examples of other alternative sweeteners that have not shown to affect the gut.  
  • Research shows that low amounts of some bacteria (i.e. Faecalibacterium prausnitzii) can exacerbate skin disorders. It’s also thought that the quality of your intestinal barrier can influence skin health. 
  • As the human body ages, digestion may naturally alter. Acid production may drop in the stomach; muscles from the digestive tract may also weaken. 
  • You don’t necessarily have to remove gluten from your diet unless you have celiac disease, non-celiac gluten sensitivity, or a diagnosed allergy. However, gluten is not inherently beneficial for gut health in most people. While some components of gluten-containing grains—such as arabinoxylan oligosaccharides—may have prebiotic effects and support beneficial bacteria like Bifidobacteria, these benefits are often outweighed by gluten’s potential to trigger inflammation or disrupt the gut barrier, especially in those with underlying digestive or immune issues.
  • The enteric nervous system (ENS) allows the gut and brain “talk” to each other. This is known as the gut-brain axis, and improving its function includes managing stress, consuming whole foods, and taking pre- and probiotics into consideration. 
  • Some people don’t need to poop every day, and that may be okay! Your pooping schedule depends on individual factors, such as medications, current supplements, chronic symptoms/condition, age, fluid intake, exercise, etc.
  • Moderate coffee intake may help relieve constipation and support gut health by providing polyphenols that promote the growth of beneficial gut bacteria.
  • The gut responds to regular exercise, which is why a functional medicine clinic may ask you to increase physical activity. Regular exercise – when added to a regime of formal health interventions and lifestyle changes – may improve digestion by increasing the number of healthy gut bacteria. 

Don’t settle for bloating, cramping, and other digestive issues. Reset your gut with our personalized medicine approach – contact us here to request your consult at the Toronto Functional Medicine Centre. 

Disclaimer: The information in this article is designed for educational purposes only and is not intended to be a substitute for informed medical advice or care. This information should not be used to diagnose or treat any health problems or illnesses without consulting a doctor. You should always consult with a health care practitioner before relying on any information in this article or on this website. Never delay or disregard seeking professional medical advice from your doctor or other qualified healthcare provider because of information you have read from the Toronto Functional Medicine Centre website or other affiliate media. 

 

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