Leigh Merotto, RD • GutFit Nutrition, Toronto, ON (2026)

10/10/2026

🎤 Thank you The Baby Shows for letting me host one of their stage seminars last weekend! We talked about how the period of gestation (during pregnancy) up to 2 years of age is critical in shaping a baby's lifelong health 👶 🦠 & the concept of the "First 1000" days influences the gut microbiota and maturation of their immune system.

We covered:
🗓️ The first 1000 days impact on lifelong disease risk
🤰 How Mon can support baby's microbiome & role of breastfeeding
👦 How to choose a safe and clinically studied probiotic for conditions like infant colic, diarrhea and eczema.

I also spent the full day at the BioGaia Canada booth. BioGaia is a probiotic science company I have been doing some consulting & health science translation work with for the past year. They were founded in Sweden over 30 years ago & currently have 295 clinical trials (many randomized, double blind controlled) on their patented L Reuteri strain. Their probiotics currently have several healthcanada approved indications, and they are dedicated to ensure that their products have been rigorously tested in a lab with human subjects to ensure the claim matches the outcome. In today's world of overused "science backed" claims.. Though I seldom work with brands & am incredibly selective about companies I partner with.. They are truly are dedicated to real, ethical and transparent science which is why I've been thrilled to partner with them.

I had a great time supporting the pharmacy reps & team members as an on-site Dietitian in answering visitor's questions on nutrition, probiotic science & gut microbiome related questions.

A few great ones:
✨ Proper Vitamin D supplementation for children & role in immunity
✨How a clinically studied probiotic differs from a drug store product with no studies behind it
✨Why more strains OR higher CFUs isn't always better in a probiotic
✨Why dose, strain & combination matters with probiotics, and how to choose a clinically studied strain for a specific health goal
✨How moms gut microbiome health impacts babies

Already looking forward to coming back to the spring show!

10/07/2026

What are the most common carb intolerances if you IBS? 👀 🥐 🫘 🥦

In my latest episode I chat with Jessica Roocroft RD (Jessica Roocroft) to discuss a topic we see all the time as IBS dietitians! What carbohydrate intolerance actually means and why certain carbohydrates can cause bloating, gas, pain, urgency in people like you with IBS and GI issues.

We break down all things FODMAPs, including lactose, fructose, fructans, GOS, mannitol, and sorbitol.

We also chat about a lesser known carb intolerance known as sucrose intolerance and sucrase-isomaltase deficiency. We explain what these conditions mean, how they can affect your gut, and what managing them can actually look like in real life!

And importantly, we discuss how carbohydrate intolerances can be appropriately assessed, including why we don’t recommend at home breath tests like the Food Marble, and which enzyme products are worth the money.

If you keep cutting foods out to try to “fix” your IBS symptoms and still don't feel better, this episode is for you. 🎧

Comment EPISODE 67 to listen + watch now! 👇

10/06/2026

Are bathroom breaks sabotaging your PB?? 😩🏃🏼‍♀️

You spend months training for a marathon, only for your gut to completely derail you on race day, sending you running to the bathroom multiple times, costing you 5, 10, even 15 minutes off the time you were hoping for.

While GI issues are common in runners (and having IBS or a GI condition makes them worse), it’s NOT something you have to settle with.

And.. It probably wasn’t just because you ate the “wrong” breakfast. 😉

There are 2 areas of consideration (& I help my athlete clients with IBS here):

⚡ GI Friendly Race Prep Nutrition (Short Term):

🍳 Morning of: Having a practiced & gut friendly (low fodmap, low fibre, low fat) race day breakfast is yes, still important (but not the only thing!)

🍝 Carb Load: Ensuring it’s the right amount for you (depends on your usual carb intake!) and TYPE of carbs that are GI-friendly can make or break your race.

🥤 Race Fuel: Having a game plan for how much carb & fluid to take, what types and when can also make or break your race (and your gut).

🌱 & Building Gut Resilience (Long Term):

🚽 Supporting your bowel routine: Often runners get diarrhea on race day due to constipation leading up to the race. Making sure you are properly emptying before the race can make a huge difference!

🔥 Calming inflammation in the gut: Creating a healthy gut environment so that your gut IS more able to tolerate the stress of racing when those demands are placed.

🏃‍♀️Gut Training: Figuring out what meals pre running/ hard training as well as training your gut to handle more fluids & carbs over time.

So, if you’re an athlete or active individual who feels like you’ve “tried it all” but you’re STILL stuck in the cycle of bloating, pain and unpredictable bowel movements…

I’m breaking down the most common mistakes that could be keeping you stuck inside my free LIVE IBS training 🙌🏻

You’ll learn how to calm your symptoms, get clarity on what your gut actually needs, and build an IBS management plan that fits your training plans, travel, adventures & real life.

🔥 Comment TRAINING to save your free seat!

09/28/2026

Does diet and nutrition make a meaningful difference in cancer treatment, recovery, and reducing your risk of recurrence?

At 27, in the best shape of her life, working as a dietitian, Jean LaMantia noticed a stiff neck that wouldn't go away.

It took months, a misdiagnosed round of "bronchitis," and a chest X-ray before she finally learned she had Hodgkin’s lymphoma, with a 15-centimeter tumor in her chest.

She went through six months of chemotherapy and a month of radiation.

What she didn't expect was that finishing treatment wouldn't feel like the relief she'd imagined. It started an entirely new phase of anxiety and hypervigilance about recurrence, and a search for answers her medical team hadn't fully addressed. “This experience was horrible & how can I prevent the cancer from coming back?”

That search became the foundation of her career.

I’m so excited to share this weeks episode of the GutFit Nutrition Podcast where I chat with Jean about how inflammation, gut health, and immunity intersect to influence cancer outcomes, why there's no single "cancer diet," and dispelling some common nutrition myths like whether sugar feeds cancer and if you really need to give up alcohol.

If you're currently in treatment or supporting a friend or family member with their cancer journey, I hope you tune into this supportive and evidence based conversation about how evidence based nutrition and gut health can truly impact your outcomes. 🎧

🎧 Listen on your favourite podcast app: pod.link/1809215958/episode/ZGVhZDVmODAtN2YzMy00ODA3LWExMDctY2MzY2FjODMxY2I5?view=apps&sort=popularity

📺 Prefer video? Watch on YouTube: www.youtube.com/watch?v=OPn1FfuVpMk&list=PLvcW_qBMEYDYqk4i7IhaMq7JKOBaB0h1s&index=1

09/22/2026

Is that supplement actually helping your running performance..

Or is it just a waste of money? Or arguably worse.. Another stressor on a gut that's already unpredictable? 👟

In my latest episode I sat down with Amy Goblirsch Amy | Dietitian for Runners to go through the supplements you most ask us about!

This includes creatine, sodium bicarbonate, collagen, pre-workout, caffeine, tart cherry, beetroot, ketones, and electrolytes.

We rated each one underrated, overrated, or properly rated based on the actual research!

We also broke down the GI considerations we would have for our clients for each one, so if you're running with IBS or a sensitive gut, you'll know exactly what to expect and how to reduce symptoms if you decide to try any of them.

If you've been confused about which supplements are worth your money (and your GI system), this one is for you!

Comment EPISODE 65 to listen + watch now! 👇

09/21/2026

It’s not always “just IBS”.

Here are just a few (often overlooked) examples of triggers that may set off sudden urgency.

1. The gut-brain interaction: The gut-brain connection is a two-way communication system.

This is how stress, anxiety, and important events can trigger digestive symptoms.

2. Intolerance to certain sugars or carbohydrates

Such as… Lactose Intolerance - Difficulty digesting lactose, a sugar in “wet” dairy, due to low levels of lactase enzymes

Or, Sucrase Isomaltase Deficiency: Difficulty digesting starches and sucrose, a type of sugar, to varying extents.

3. Runner’s Diarrhea: Both prolonged and high intensity exercise can compromise the intestinal barrier and lead to a risk of endotoxins entering the bloodstream.

This effect can also be worse if you run hard or long while fasted!

4. Overactive Gastrocolic Reflex: The gastrocolic reflex is a normal response that tells our colon to empty when our stomach fills with food.

But, those with GI conditions like IBS often have a stronger colonic response to this reflex (aka - you need to urgently 💩 after eating).

5. Bile Acid Diarrhea: In bile acid diarrhea, excess bile acids reach the large bowel and irritate the lining, drawing in water and leading to particularly
urgent, loose stools.

If you’ve been out enjoying your day when you’ve needed to all of a sudden find a bathroom ASAP, it can be a real buzz kill.

And it might have left you with anxiety about leaving your house. But remember…

You aren’t alone! ❤️

And there are ways to prevent this from happening.

Follow for evidence-based IBS & gut health tips! Leigh | IBS, Gut & Fitness Dietitian IBS, Gut Health & Fitness Dietitian For Women Jessica Roocroft

09/21/2026

How do you know if that probiotic will REALLY help your gut issues like bloating, pain, diarrhea or constipation?

If you’ve ever gone out to purchase a probiotic supplement, you've probably been inundated with shiny claims like “proven formula” “science-backed” and “helps with IBS, bloating, etc”

But here’s the issue I see time and time again as a Registered Dietitian specializing in gut health.

Most probiotics on the market make their claims based on SECONDARY data.

This means that they make their claims based on external studies they did not conduct themselves.

This is not high quality science. ❌ 🧬

Here’s one common example → A company buys a specific probiotic strain (like Lactobacillus rhamnosus GG) from a supplier. The supplier has extensive clinical data showing the strain helps with digestion. The company then uses that data to claim their pill helps with digestion. 🤦🏻‍♀️

Here’s another common example → Companies cite decades of general research on a species (e.g., Bifidobacterium bifidum) to imply that their specific formula will yield the exact same health benefits.

A few key issues with using secondary data include...
🚩 Survival & delivery → Secondary data rarely accounts for whether a specific company's capsule can survive human stomach acid to actually reach the gut alive.
🚩 Dosage Discrepancies → A secondary study might show a health benefit at 10 billion CFU (Colony Forming Units). However, a company might only put 1 billion CFU of that strain in their product while still citing the study.
🚩 The “Matrix Effect” → A strain tested in a controlled laboratory setting or a specific yogurt base might behave entirely differently when mixed with five other strains and compressed into a dry capsule.

Put simply...

👎 When it comes to solving your digestive issues and buying a product that truly does what it says, you don’t want to be taking something that was never tested in a lab with human subjects!

💬 Questions about probiotic science? Comment below! ⬇️

09/21/2026

Last 3 weeks of 5K training for a PB + pancreatic cancer research! 🏃‍♀️

Now it’s time to pull back the volume, recover, and feel fresh for this weekend’s Constantine Yorkville Run 5K! 🎯

Week of August 24–30
💪 1.5 hours strength + 1 hour hot yoga
🏃‍♀️ 70 km total mileage
• 5 easy runs
• 1 speed session: 800 m repeats at 5K pace with 400 m jog recoveries, 15 km total
• Long run workout: 3 × 3 km at half-marathon pace with 4 min jog recoveries, 23 km total

Week of August 31–September 6
💪1.5 hours of strength + 1 hour hot yoga
🏃‍♀️65 km total mileage
• 5 easy runs
• 1 speed session: 200 m repeats + warm-up/cool-down, 16 km total
• Long run workout: 350 m elevation gain + 6 × 2 km at half-marathon effort, 24 km total

Week of September 7–13
🚴‍♀️ 1.5 hours biking
💪 2 hours strength + 1 hour hot yoga
🏃‍♀️ 70km total mileage
• 5 easy runs
• 1 speed session: 5 × 1 km at 5K pace with 600 m jog recoveries, 16 km total
• Long run workout: 2 × 2 miles + 1 mile at half-marathon effort, 21 km total

Fueling the longer runs 🥤 For runs longer than 75 minutes, I take in around 50–60 g of carbs + 250–500 mL of fluid per hour.

I never caffeinate for workouts, but Sunday’s long run is always followed by a flat white ☕️

One of my key rewards for getting the long run done! 😂 ☕️

I’m almost at the $2500 fundraising goal for Pancreatic Cancer North America 💜💜 Here are 2 ways you can help support research for early detection for the world’s toughest cancer:

1️⃣ Donate directly to my fundraising page:
gutfitnutrition.com/pancreas
100% of proceeds will go to Pancreatic Cancer North America.

2️⃣ Shop the GutFIt Nutrition Resource Suite throughout September.

For the month of September, 50% of all proceeds from my online shop (meal plans, resource bundles & courses) will be donated to the charity!

I’ve also extended the 10% discount this week - use code PANCREAS10 at checkout!
gutfitnutrition.com/shop-resources

Thank you so much for your support, and here’s to better outcomes and more positive patient stories in the future. 💜

09/21/2026

$2700 raised for pancreatic cancer research! Pancreatic Cancer North America 💜💜

Lovely Sunday racing in the Constantine Yorkville Run 5K, cheered by friends & family, meeting some new lovely people all in the name of fitness & spreading the word on a rare and underfunded cancer!

Pancreatic cancer is one of the most rare cancers, but long considered the most difficult to treat. Why?

Underfunding.
Lack of physician knowledge of common symptoms.
Minimal symptoms until it's stage 3 and often 4.

Thank you to everyone who donated to help raise money for PancreaticCancerNorthAmerica and the amazing work they do in pushing for early detection & better access to treatment and care.

In their words "Our current healthcare system is not built for the speed of this cancer".

We need earlier detection, more targeted treatments and yes (in my opinion) better awareness of nutrition and lifestyle management.

Overall a blast of a Sunday. Bike commute downtown, warm up + strides around yorkville area, raced the 5K, checked out booths with my family & friends, some more city biking, then hit up a cafe for decaf latte and St Lawrence Market for groceries and gluten free crepes. Then later a 10km top up for some extra mileage!

⏱️ Chip time was 20:01 (21st out of 555 female). I thought I had a few seconds buffer with my GPS watch splits to beat my 19:55 PB but I guess not. 😩 😂 last years Yorkville race was 20:49 so I'm happy with the fitness improvement overall! Fuelling, warm up, sleep, GI all went well. 🙏

Grateful to have both my parents cheering at the finish line. 💜

Survival Not Sympathy! 💪💜

09/21/2026

Is that supplement actually helping your running performance..
Or is it just a waste of money? Or arguably worse.. Another stressor on a gut that's already unpredictable? 👟

In my latest episode I sat down with Amy Goblirsch, the running dietitian, to go through the supplements you most ask us about!
This includes creatine, sodium bicarbonate, collagen, pre-workout, caffeine, tart cherry, beetroot, ketones, and electrolytes.

We rated each one underrated, overrated, or properly rated based on the actual research!

We also broke down the GI considerations we would have for our clients for each one, so if you're running with IBS or a sensitive gut, you'll know exactly what to expect and how to reduce symptoms if you decide to try any of them.

If you've been confused about which supplements are worth your money (and your GI system), this one is for you!

🎧 Listen on your favourite podcast app: pod.link/1809215958/episode/ZThkNzI1ODMtZGVjYy00YTFjLWIyMjQtNzE2ZDkwMzEyNTI4?view=apps&sort=popularity

📺 Prefer video? Watch on YouTube: www.youtube.com/watch?v=b2R4XXVDcnU&list=PLvcW_qBMEYDbYdNeRF-LmLnH_YDoKt8fM&index=1

Leigh Merotto, RD • GutFit Nutrition

10/10/2026

10/07/2026

10/06/2026

09/28/2026

09/22/2026

09/21/2026

09/21/2026

09/21/2026

09/21/2026

09/21/2026

Address

Website

Alerts

Contact The Practice

Shortcuts

Sponsored

Share

Category

Listing takedown request