Every year on May 29, the World Gastroenterology Organisation marks World Digestive Health Day, a global initiative focused on raising awareness around digestive health and how often symptoms get overlooked or dismissed.

This year’s theme is “Chronic Diarrhea: Don’t Flush the Signs Away,” which is really about paying attention to what the body is trying to communicate instead of brushing it off or normalizing it. It ties into something we talk about a lot here: digestion isn’t an isolated system. What’s happening in your gut can influence how you feel overall, from energy to mood to day-to-day comfort.

Most people think about their gut the way they think about plumbing, you don’t pay attention to it until something goes wrong. And when something does go wrong, it’s uncomfortable, embarrassing to talk about, and often normalized for years before anyone takes it seriously. Bloating after every meal? That’s just how I am. Constipation that comes and goes? My digestive system has always been weird. Stomach cramps that nobody can explain? I must just have a sensitive gut.

Your digestive system isn’t supposed to be a source of daily discomfort, and it doesn’t operate in isolation from everything else in your body. It houses around 70–80% of your immune system. It’s involved in producing most of your serotonin. It communicates directly with your brain through the vagus nerve, and it’s where you absorb the nutrients that fuel every system in your body. So taking care of it isn’t a niche health interest. It’s foundational.

So in honour of World Digestive Health Day, let’s talk about what your gut is actually doing, what happens when things go wrong, the common signs most people dismiss for too long, and what it actually looks like to nourish it properly.

What Your Gut Is Actually Doing

The digestive system runs from your mouth all the way to your colon, and what happens along that entire journey is a lot more sophisticated than most people realize.

Digestion actually starts in your mouth. Saliva contains enzymes, amylase in particular, that begin breaking down carbohydrates before food even hits your stomach. When you chew more thoroughly, you’re helping that first step along, which means less work for the rest of your digestive system. That’s part of why eating slowly matters, and why it’s one of the most overlooked pieces of digestive health.

From there, food moves into the stomach, where hydrochloric acid and pepsin break down proteins and help reduce harmful pathogens. The stomach is acidic by design, that acid is not a problem, it is the mechanism. When stomach acid is chronically reduced (from stress, age, or long-term antacid use), food doesn’t break down as well as it should. Proteins may not be fully processed, and over time this can show up as bloating, reflux, or nutrient gaps.

The small intestine is where most nutrient absorption happens. This is where nutrients are broken down into their smallest components and absorbed through the gut lining into the bloodstream. How well this happens depends on the health of that lining, along with the balance of the gut microbiome. When the gut lining is compromised, absorption can be affected, even if the diet itself is nutrient-rich.

The large intestine is where your gut microbiome lives, the trillions of bacteria, fungi, and other microorganisms that help with a wide range of functions. They ferment fibre into short-chain fatty acids that fuel the cells in your colon, help regulate inflammation, support immune function, and communicate with the brain. It’s one of the most complex parts of the digestive system, and an important one for overall health.

The digestive system absorbs essential nutrients that fuel the body’s functions and supports long-term health. By prioritizing nourishing foods and making informed lifestyle choices, individuals can proactively maintain their digestive health, reduce the risk of gastrointestinal disorders, and improve their overall quality of life. (World Gastroenterology Organisation, WDHD 2025 Campaign)

Your Gut Is Connected to Everything

Your immune system lives here

A huge part of the immune system lives in and around the gut, which is part of why gut health affects so much more than digestion alone. The gut helps “train” the immune system, teaching it what’s harmless and what actually needs a response. When the gut microbiome is supported, the immune system tends to respond more appropriately instead of overreacting. And when the gut is struggling, it often shows up in other ways too. So when people deal with things like frequent sickness, worsening seasonal allergies, or chronic inflammation, the gut is often part of the conversation. Not the entire picture, but definitely part of it.

Your mood and brain

The gut and brain are much more connected than most people realize. In fact, most of the body’s serotonin is produced in the gut, and the digestive system has its own huge network of neurons, often called the “second brain.” This connection goes both ways. Your gut is constantly sending signals to the brain through the gut-brain axis, while the brain is sending signals right back down to the gut. The microbiome is also involved in producing and influencing neurotransmitters connected to mood, stress, and cognitive function. Which honestly helps explain why stress can affect digestion so quickly, and why gut issues can sometimes show up alongside things like brain fog, anxiety, or low mood. They’re not separate systems nearly as much as we tend to think they are.

Your skin

The gut-skin connection is real, and research around it keeps growing. The health of the gut microbiome and the state of the digestive system can influence a lot more than digestion alone, including what shows up on the skin. When the gut is irritated, inflamed, or out of balance, it can sometimes show up externally through things like breakouts, redness, ensitivity, or other ongoing skin issues. In a lot of cases, the skin ends up acting like an outward reflection of what’s happening internally. Which is also why focusing only on topical products doesn’t always lead to lasting changes. Sometimes the skin is part of a bigger conversation happening inside the body too.

Your energy

Your gut is where you absorb the nutrients that produce your energy. Iron. B12. Folate. Magnesium. Vitamin D. If your gut lining is damaged, your stomach acid is low, your microbiome is disrupted, or your digestion is incomplete, you can eat all the right things and still not be absorbing them properly. Fatigue that doesn’t respond to sleep, that doesn’t improve even when diet looks decent on paper, is often a gut absorption issue. The food is going in. It’s just not getting through.

Signs Your Gut Is Trying to Tell You Something

A lot of people normalize gut symptoms for years, sometimes decades, before taking them seriously. Part of that is embarrassment. Part is that they’ve been present so long they feel like just the way things are. Part is that when they do bring it up, they’re often told everything looks normal on a basic test and sent on their way.

Here are the signs worth actually paying attention to:

Digestive symptoms

• Bloating that happens regularly, especially after meals — the kind that makes you look and feel pregnant by the end of the day
• Gas that’s more than occasional and feels disproportionate to what you ate
• Constipation — fewer than three bowel movements per week, stools that are hard and difficult to pass, or a persistent feeling of incomplete emptying
• Diarrhea that’s frequent, urgent, or unpredictable
• Alternating constipation and diarrhea
• Stomach cramping and pain that doesn’t have a clear single-food cause
• Acid reflux or heartburn that’s become a regular feature of your life
• Nausea after eating, particularly fatty meals
• Feeling very full very quickly — early satiety that’s out of proportion with how little you’ve eaten
• Undigested food appearing in stool
• A gnawing or burning sensation in the upper abdomen

Systemic signs that point back to the gut

• Fatigue that doesn’t improve with adequate sleep or a decent diet — absorption issues
• Brain fog, difficulty concentrating, mental haziness that isn’t explained by sleep deprivation or stress alone
• Skin conditions: eczema, acne, rosacea, psoriasis, persistent unexplained rashes
• Food sensitivities that are multiplying over time — reacting to more and more things that you used to tolerate fine
• Frequent illness or slow recovery from infections
• Low mood, anxiety, or irritability that seems to worsen alongside gut flares
• Joint pain and inflammation without a clear structural cause
• Nutritional deficiencies despite what looks like a reasonable diet

Common Gut Conditions People Live With For Too Long

Irritable Bowel Syndrome (IBS)

IBS is incredibly common in Canada, yet a lot of people spend years trying to figure out what’s actually going on and even longer finding approaches that genuinely help them feel better. What’s important to understand is that IBS isn’t “just stress” or something people are imagining. It’s a real gut-brain interaction issue, where the communication between the nervous system and the digestive system becomes more sensitive and dysregulated. That can affect things like motility, digestion, bloating, pain, and how reactive the gut feels overall. And while there isn’t one simple fix for everyone, things like nutrition, stress support, sleep, nervous system regulation, and lifestyle changes can make a meaningful difference for a lot of people over time.

SIBO (Small Intestinal Bacterial Overgrowth)

SIBO happens when bacteria that are normally supposed to stay in the large intestine start building up in the small intestine instead. Because the small intestine isn’t really designed to handle that kind of fermentation, it can lead to a lot of bloating, gas, discomfort, and issues with properly absorbing nutrients. It’s also something that many people go years without hearing about, especially if they’ve simply been told they “just have IBS.” More and more research is finding that SIBO may be part of the picture for a portion of people dealing with ongoing digestive symptoms. Testing is usually done through a breath test, and support approaches can vary depending on the person, often involving targeted antimicrobial support alongside rebuilding and supporting the gut afterward.

Inflammatory Bowel Disease (IBD)

Crohn’s disease and ulcerative colitis are immune-mediated conditions that cause chronic inflammation in the digestive tract. Canada actually has one of the highest rates of IBD in the world, with over 300,000 Canadians living with it. These are serious conditions that require medical management, but nutrition plays a critical supporting role in reducing inflammation, supporting remission, and maintaining nutritional status when absorption is compromised.

GERD (Gastroesophageal Reflux Disease)

GERD is essentially chronic acid reflux, where stomach acid regularly moves up into the esophagus and causes things like heartburn, chest discomfort, and, over time, irritation of the esophageal tissue. It’s very common in Canada, and many people end up relying on long-term medications like PPIs, which can reduce symptoms, but also lower stomach acid levels that are actually needed for digestion and nutrient absorption. At the same time, there’s a lot that often doesn’t get fully explored first, things like meal timing, eating posture, food triggers, sleep habits, and overall digestive load. For many people, these lifestyle pieces are a foundational part of how symptoms are supported alongside any medical guidance.

Chronic Diarrhea

This year’s WDHD campaign is also putting a spotlight on chronic diarrhea as something that’s often underreported and still pretty stigmatized. The World Gastroenterology Organisation notes that it can affect a lot of people globally and may be linked with things like IBS, IBD, celiac disease, microscopic colitis, bile acid issues, infections, and more. But it often doesn’t get properly talked about or followed up on because people feel embarrassed bringing it up. Their message is simple: this is something that deserves attention, not silence, and if it’s been going on for more than a few weeks without a clear reason, it’s worth getting looked into rather than just pushing through it.

The Foundation of Gut Health

Fibre

If there’s one dietary factor that matters most for gut health, it’s fibre, especially fibre from a wide variety of plant foods. Gut bacteria ferment fibre into short-chain fatty acids like butyrate, which help nourish the colon, support the gut barrier, regulate inflammation, and support immune function. More fibre diversity generally means more microbiome diversity, which is one of the strongest markers of gut health.

Research, including the American Gut Project, has found that people eating 30+ different plant foods per week tend to have significantly more diverse microbiomes. That’s not 30 servings of the same vegetables, but 30 different plants like fruits, vegetables, legumes, whole grains, nuts, seeds, and herbs. For reference, the daily fibre target is about 25g for women and 38g for men, which most Canadians aren’t reaching.

Fermented foods

Fermented foods might feel trendy now, but they’ve been part of traditional diets for centuries. Foods like kimchi, kefir, sauerkraut, miso, and yogurt naturally contain beneficial bacteria that help support the gut microbiome. Research is starting to back up what traditional food cultures have long known. A 2021 Stanford study found that higher fermented food intake improved microbiome diversity and reduced inflammatory markers, in some cases even more than fibre alone.

That doesn’t take away from fibre, it still matters a lot. But fermented foods are often missing from modern diets, even though they can play a supportive role in overall gut balance.

• Full-fat plain yogurt with live cultures — the most accessible and widely tolerated fermented food
• Kefir — more diverse bacterial strains than yogurt, excellent in smoothies
• Sauerkraut and kimchi — fermented vegetables; the lacto-fermented kind in the refrigerated section, not the vinegar-pickled shelf-stable kind
• Miso — in soups, dressings, marinades
• Tempeh — fermented soy with a complete protein profile
• Kombucha — in moderate amounts; some people with IBS or SIBO don’t tolerate it well

Hydration

Water is essential to every step of the digestive process. It softens stool, supports motility, helps enzymes function, and maintains the mucus layer that lines and protects the gut wall. Chronic mild dehydration is one of the most common and most overlooked contributors to constipation and sluggish digestion. The target is roughly 8 cups (2 litres) per day for most adults, more with exercise, hot weather, or high fibre intake. Coffee and alcohol don’t count toward this total, both are dehydrating.

Anti-inflammatory eating

Chronic gut inflammation, driven by a poor diet, dysbiosis, stress, and lifestyle factors, is at the root of most persistent gut conditions. An anti-inflammatory dietary pattern reduces that background inflammatory burden:

• Fatty fish (salmon, sardines, mackerel) two to three times per week for EPA and DHA omega-3s
• Extra virgin olive oil as the primary cooking fat — oleocanthal has direct anti-inflammatory effects
• Colourful vegetables and fruits — each colour represents different polyphenols that reduce oxidative stress and inflammation
• Whole grains over refined grains — the fibre and phytonutrients matter
• Legumes regularly — one of the most gut-supportive food groups for the microbiome
• Ginger and turmeric — evidence-backed anti-inflammatory herbs that also support digestive motility

What to reduce

• Ultra-processed food — emulsifiers, artificial sweeteners, and additives in packaged food have documented disruptive effects on the gut microbiome. Polysorbate 80 and carboxymethylcellulose, for example, have been shown to alter the gut microbial environment and increase gut permeability in research.
• Refined sugar — feeds pro-inflammatory bacteria, starves the beneficial ones, and disrupts the microbial balance that supports gut and immune function
• Alcohol — directly damages the gut epithelium, disrupts tight junctions, and alters the microbiome; even moderate intake has measurable effects on gut barrier integrity
• Eating too fast — under-chewed food reaches the stomach in chunks that require more acid and more time to process, contributing to bloating, gas, and incomplete digestion

Eating in a way that lets your gut do its job

This part is seriously underrated. It’s not just about what you eat, it’s also how you eat it.

A lot of people are eating while stressed, multitasking, scrolling, driving, standing in the kitchen, or rushing between things, and the body notices that. When you’re in that stressed, “go-go-go” state, your nervous system shifts into fight-or-flight mode, where digestion stops being the priority. Your body literally starts redirecting energy elsewhere. Blood flow to the gut decreases, digestive secretions slow down, and the whole process becomes less efficient.

That’s why slowing down before meals can make such a difference, even if the food itself stays the same. Sitting down, taking a breath, chewing properly, and actually tasting your food helps shift the body into what’s called “rest and digest” mode, where the digestive system can function much more smoothly.

The Lifestyle Side of Digestive Health

Sleep

The gut microbiome has its own circadian rhythm. It responds to your sleep-wake cycle, and disrupting that cycle disrupts the microbiome. Research has found that people with disrupted sleep schedules, especially shift workers, often have noticeably different gut microbiomes compared to people with more consistent routines. Poor sleep has also been linked to things like increased gut permeability, changes in digestion and motility, and worsening digestive symptoms overall. Which honestly helps explain why you can eat “healthy” and still not feel great if your body never really gets proper rest. Seven to nine hours of consistent sleep isn’t just about feeling rested. It’s part of supporting the gut too.

Movement

Regular physical activity supports gut motility, the wave-like contractions that move food through the digestive tract. Constipation is significantly more common in sedentary people. Exercise also reduces gut transit time (the time it takes food to move through the system), which reduces the time potentially harmful compounds spend in contact with the gut wall. Even a 20 to 30 minute walk daily has meaningful effects on gut motility and microbiome diversity.

Stress management

The gut-brain axis runs both ways. Chronic stress suppresses digestive function, increases gut permeability, and alters the microbiome. People under sustained stress have measurably different gut bacteria than those who aren’t. This is not just correlation, the mechanisms are direct. Cortisol and other stress hormones alter gut motility, reduce secretory IgA (the gut’s first-line immune defense), and compromise the tight junctions that maintain gut barrier integrity. Managing chronic stress is gut health work. Genuinely.

Medications worth paying attention to

Several commonly used medications have significant effects on gut health that most people aren’t told about:

• NSAIDs (ibuprofen, naproxen, aspirin) — directly damage the gut lining and increase intestinal permeability with regular use
• Antibiotics — kill beneficial bacteria alongside pathogens; always take a high-quality probiotic during and after antibiotic courses to support microbiome recovery
• Proton pump inhibitors (PPIs) taken long-term — reduce the stomach acid needed for protein digestion, mineral absorption (particularly iron, B12, magnesium, and calcium), and first-pass pathogen killing
• Long-term laxative use — some types can create dependency and worsen the underlying motility issues

When to Actually See Someone

This section matters because a lot of people tolerate gut symptoms for far too long without getting a proper evaluation. Some symptoms are genuinely warning signs that need investigation sooner rather than later:

• Blood in stool — always warrants a conversation with a doctor, even if it seems minor. This includes bright red blood (likely lower GI) and dark tarry black stools (upper GI bleeding).
• Unexplained significant weight loss — losing weight without trying is a red flag across any system
• Chronic diarrhea lasting more than four weeks without a clear cause
• Persistent abdominal pain that is new, changing, or waking you from sleep
• Difficulty swallowing that is worsening
• Anemia without an obvious explanation — gut blood loss or malabsorption could be the cause
• Symptoms that overlap with inflammatory bowel disease: urgency, bloody or mucusy stool, frequent diarrhea, significant abdominal cramping, weight loss, fatigue
• A first-degree relative with colorectal cancer or inflammatory bowel disease — family history changes your screening timeline

In Canada, colorectal screening is generally recommended starting around age 50 for people considered average risk. One of the easiest starting points is usually a FIT test (fecal immunochemical test), which is non-invasive and can often be done at home. Honestly, a lot of people keep putting it off because it sounds uncomfortable or intimidating, but the first step is usually much simpler than they expect. So if you’re over 50 and haven’t looked into screening yet, this might be a good reminder to finally put it on the list.

World Digestive Health Day exists because digestive health is genuinely foundational to everything else. It’s not a niche topic. It’s not something to only think about when your stomach is actively bothering you. Your gut is running your immune system, producing your mood-regulating neurotransmitters, absorbing the nutrients that fuel every cell in your body, and communicating in real time with your brain. Taking care of it is not optional.