ADHD and IBS: Managing Two Invisible Challenges

“ADHD and IBS: Managing Two Invisible Challenges” was written by Rebekah Greenslaugh, MSc and edited/reviewed by Maurya Hart, BSc(NutrSc), RD Jackie Silver MHSc, RD.  

Medical Disclaimer: The information in this article is meant for educational purposes only. It is not intended to be personalized medical or nutrition advice. For a plan tailored to your needs, please consult with a Registered Dietitian or qualified healthcare professional.

Disclosure: This post may contain affiliate links with which I may earn a small commission but at no additional cost to you. Affiliate links help bloggers like me to provide you with free content. All opinions expressed here are genuine. 

Last updated: July 11, 2025

Introduction: What’s the Deal with ADHD and Gut Issues?

If you live with ADHD and also experience frequent bloating, diarrhea, constipation, or stomach pain, you’re not alone. Research is starting to show a strong link between ADHD and irritable bowel syndrome (IBS). In this blog post, we’ll break down what the research says about the connection between ADHD and IBS, common challenges, and simple, realistic strategies to help support your gut health, even if you struggle with executive functioning or food sensitivities.

What Is IBS and How Does It Show Up?

IBS stands for irritable bowel syndrome. It is a type of functional gut disorder, meaning the digestive system doesn’t work (function) the way it should. This is different from structural or organic gut disorders, like Crohn’s disease or ulcerative colitis, which involve visible inflammation or damage to the digestive system. 

Common symptoms of IBS include:

• Bloating or stomach pain that gets better after going to the bathroom
• Diarrhea, constipation, or both
• A feeling of incomplete bowel movements
• Gas, cramping, or urgency (needing to go to the bathroom suddenly and right away)

There are a few subtypes of IBS: IBS-C (mostly constipation), IBS-D (mostly diarrhea), and IBS-M (mixed, a combination of constipation and diarrhea).

It’s important to note that IBS is different from just having constipation or diarrhea sometimes. IBS is a chronic condition that includes abdominal pain and changes in bowel habits over time, often with no clear cause. 

If you’ve noticed that your bathroom routine is different than usual, and it doesn’t go back to normal after a long time, it might be time to see a healthcare professional. 

The ADHD and IBS Connection: What Does the Research Say?

Individuals with ADHD are more likely to have IBS than people without ADHD. Very recently, a large study (called a meta-analysis) analyzed many smaller studies and put the results together. They included over 3 million people in their analysis, and found that adults with ADHD are 1.63 times more likely to be diagnosed with IBS!

Overall, research increasingly shows a link between ADHD and gastrointestinal (GI) issues, in both children and adults. Several studies have observed that children with ADHD are more likely to experience GI symptoms such as constipation, and encopresis (involuntary fecal soiling). These findings suggest an overlap between the brain and the digestive system that may affect gut function early in life.

Additional evidence from a large U.S. healthcare claims study supports this relationship, showing that adults with ADHD were significantly more likely to be diagnosed with IBS compared to adults without ADHD.

There is a consistent and significant link between ADHD and GI problems, reinforcing the need for an approach that helps manage both neurological and digestive symptoms. Let’s take a closer look at what is going on.

1. The Gut-Brain Connection

Your brain and gut are in constant communication through nerves, immune signals, and gut bacteria. In ADHD, the brain uses certain chemicals like dopamine and serotonin differently, and these same chemicals also affect how the gut moves and feels. These differences may help explain why people with ADHD are more likely to have gut issues like IBS.

2. Gut Microbiome Differences

The gut microbiome is the community of bacteria that is in our digestive system. People with ADHD may have different gut bacteria than people without ADHD. 

This imbalance in the microbiome (called dysbiosis) is linked to both ADHD symptoms and IBS. This difference in the bacteria in the gut could be one reason that those with ADHD have a higher chance of having IBS. 

There is also growing research suggesting that probiotic supplements may help support gut health and help reduce IBS symptoms. Some strains, such as Bifidobacterium and Lactobacillus, have shown promise in managing IBS symptoms. 

3. Stress and Anxiety

Many folks with ADHD also experience anxiety, which can trigger or worsen IBS symptoms. The stress response can alter the way the gut moves and how sensitive it is, making symptoms more intense during times of stress. 

4. ADHD Medication Side Effects

ADHD medications, especially stimulants like methylphenidate, can sometimes cause side effects like reduced appetite or stomach pain. These symptoms can make it harder to eat regularly, which may worsen IBS.

5. Dietary Patterns and Irregular Eating

Executive functioning challenges can make it hard to plan regular meals, shop for groceries, or cook. Skipping meals and rushing through food can trigger IBS flare-ups, especially when combined with common ADHD medications that suppress appetite.

While the research is still evolving, and results can vary from person to person, working with a registered dietitian can help you find strategies that fit your needs and symptoms. At Jackie Silver Nutrition, our team of dietitian nutritionists can support people with ADHD and IBS to meet their nutrition and health related goals.

Why the Low FODMAP Diet Isn’t Always ADHD Friendly 

You may have heard of something called the low FODMAP diet as a way to manage IBS symptoms. FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. These are types of carbohydrates that may be difficult for your body to digest, and can trigger symptoms like bloating, gas, and discomfort.

FODMAPs are found in a lot of different foods, such as certain fruits, vegetables, grain products (including bread), and dairy products. The low FODMAP diet works by removing these foods that can ferment in the gut and cause IBS symptoms.  Although it is temporary, it involves cutting out a lot of food groups, which can be extremely challenging. 

Especially for ADHDers who may have specific sensory preferences, routines, and hyperfixations, the low FODMAP diet may not be a realistic or feasible way to manage IBS symptoms. It requires advanced planning, food tracking, and a structured reintroduction phase, all of which can be challenging due to executive functioning demands. 

It can also further restrict an already limited list of safe or preferred foods. Instead of going fully low FODMAP, many people with ADHD and IBS may benefit from a simpler approach, such as identifying a few specific trigger foods, trying gentle swaps like lactose-free milk, and focusing on what can be added rather than removed. A registered dietitian can help guide you through this process in a flexible, supportive way.

While a strict low FODMAP plan might not be realistic for everyone, there are still plenty of small, manageable ways to support gut health, especially when they’re tailored to how your brain works. Let’s look at some simple strategies that can actually fit into your routine. 

ADHD and IBS: How to Support Gut Health

1. Create Predictable Eating Patterns

Eating at consistent times helps regulate digestion and reduce IBS flares. You can try the following strategies to try and maintain consistent meal times:

• Linking meals to daily routines (e.g., eat after walking the dog)
• Setting alarms for meals and snacks
• Using pre-portioned meals to make decisions easier
• Batch-prepping or freezing safe foods for “bad ADHD days”

For more tips, check out our blog post on ADHD and forgetting to eat.

2. Use a simple notes app or symptom tracker to help you connect meals with symptoms over time.

Noticing how certain foods affect your body can help you identify personal IBS triggers, but traditional food journals don’t work for everyone. Instead, try using tools that fit your brain and routine:

• Take photos of your meals instead of writing them down.
• Use a voice memo app to track what you ate and how you felt.
• Log symptoms in a notes app using short phrases like “bloating after lunch” or “felt fine.”
• Use emojis or stickers in your calendar to track patterns (like 🌶 for spicy food).

3. Watch Out for Common IBS Triggers

Everyone’s triggers are different, but some common ones include:

• Caffeine (watch out for too much coffee)
• Dairy and/or lactose (choose lactose free or plant-based options)
• Artificial sweeteners and sugar alcohols, such as those found in products labeled ‘diet’ or ‘sugar-free’ (including gum, soda, and some protein bars), can cause digestive issues. Sugar alcohols like sorbitol and mannitol are known to contribute to bloating and diarrhea, especially when consumed in larger amounts. 
• Very high FODMAP foods like onions, garlic, apples, and wheat (you may want to experiment eating these in small amounts to see if they improve your symptoms). 

Some ADHDers may find it helpful and less overwhelming to try out a gentle low FODMAP diet (instead of the traditional one which is very strict and difficult to follow). As always, speak with a dietitian or healthcare professional for individualized recommendations.

4. Fiber

Fiber helps regulate your digestion, but it’s important to add it gradually and drink enough fluids.

Soluble fiber sources include: 

• Oats
• Bananas
• Chia seeds
• Carrots
• Apples 
• Oranges
• Sweet potatoes
• Beans and lentils

Insoluble fiber sources include: 

• Whole grains
• Wheat bran
• Popcorn
• Nuts and seeds
• Beans and lentils
• Skins of many fruits and vegetables

If you’re sensitive to textures, try:

• Blending oats or chia into smoothies
• Adding puréed veggies into sauces or soups
• Fiber-fortified snack bars or cereals
• Dissolving a scoop of fiber powder daily in a glass of water, such as this one or this one.

5. Fluids

When you have ADHD, it can be hard to remember to drink water. Most adults should aim for at least 8 cups of fluid per day. In general, women need about 9 cups and men need about 13 cups of fluids daily. You may need more if you’re increasing your fiber intake or experiencing diarrhea. 

Staying hydrated helps soften stool and support regular bowel movements, which can reduce constipation, a common symptom of IBS. Drinking enough water also helps replace fluids lost during episodes of diarrhea and keeps your digestive system functioning more smoothly. Proper hydration can also reduce bloating and cramping, making it a vital part of managing IBS symptoms. 

Good beverage choices include water, sugar-free drinks (in moderation), and drinks with no caffeine. Try to limit carbonated drinks and drinks high in caffeine, which may worsen digestive symptoms. 

Try the following strategies to help you stay hydrated:

• Keep a water bottle in your workspace
• Pair water with other habits (like coffee breaks or brushing your teeth)
• Use timers or hydration apps
• Add flavor enhancers like lemon, cucumber, or electrolyte powders

A Note on Fiber for ADHD and IBS

You may notice that the low FODMAP plan limits many fiber-rich foods like beans, lentils, wheat, onions, and certain fruits. It may seem confusing to hear both “limit FODMAPs” and “increase fiber” to help manage IBS symptoms.

What’s important to understand is that not all fiber causes symptoms. In fact, increasing fiber gradually, especially the right kinds of fiber, can help support digestion and relieve IBS symptoms when done carefully. Pay attention to which foods are triggering your symptoms, and aim to still include sources of fibre like fruits, vegetables, and whole grains.

Here are some of best sources of fiber that are also low in FODMAPs:

• Chia seeds (8 g fiber in 2 tbsp)

Check out these three recipes for high protein chia seed puddings. You can also add them to yogurt, smoothies, cereal, oatmeal, and more!

• Popcorn (8 g fiber in 3.5 cups)

Microwave popcorn is a great high fiber snack to enjoy that is super easy to prepare. You can also try this easy stovetop popcorn.

• Kiwi fruit (6 g fiber in 2 kiwis)

Add kiwis to your breakfast, or pair them with a protein source for a balanced snack (think yogurt, cheese, or nuts/seeds).

• Tofu (6 g fiber in 2/3 cup, cubed)

Check out this ADHD friendly Simple Tofu Teriyaki Stir Fry recipe from our meal prep series!

• Oats (5 g fibre in 1/2 cup, uncooked)

Oats are a versatile whole grain that can be prepared hot during those cold winter months, or overnight for an easy grab-and-go option in the morning. Check out these delicious overnight oats recipes. 

Tips for Managing IBS with ADHD

1. Start with one tip that feels realistic for you
2. Increase fibre intake slowly (e.g., one food at a time)
3. Leave out ingredients in your food prep area (e.g., bag of chia seeds) so you are visually prompted to add them to yogurt, cereal, smoothies, salads, etc.
4. Batch-prep a few IBS-friendly basics like rice, roasted veggies, or oats ahead of time so meals are easy to assemble on low-energy days.
5. Label foods with reminders like “add to smoothie” or use color bins to group gut-friendly items and simplify choices.

When to Talk to a Professional

If you’ve tried making changes to your diet, hydration, or routine and you’re still dealing with uncomfortable digestive symptoms, it might be time to speak with a healthcare professional. 

Symptoms like frequent stomach pain, ongoing constipation or diarrhea, unexplained weight loss, or a sudden change in your bowel habits can sometimes point to something more serious that needs medical attention. 

A registered dietitian nutritionist or doctor can help figure out what’s going on and suggest a plan that’s tailored to your needs. You don’t have to manage it all on your own, and getting support can make a big difference.

At Jackie Silver Nutrition, we offer 1:1 virtual counseling designed for neurodivergent adults, teens, and children. Whether you want to troubleshoot IBS symptoms in a neuro-affirming way or learn ADHD-friendly meal prep strategies, we’re here to help. Book a FREE 15 minute discovery call today!

We work with clients virtually across Ontario (Toronto, Hamilton, Ottawa, London, Kingston, Kitchener, Waterloo, Brampton, Mississauga, Markham, Vaughan, and more), and many US states such as New York (New York City, Westchester, Long Island, etc.), New Jersey, Connecticut, Pennsylvania, Massachusetts, and more. 

ADHD and IBS: Final Thoughts

ADHD and IBS are real medical conditions, and they’re not “just stress” or “just anxiety.” If you’ve been dismissed or told it’s all in your head, know that you’re not alone and you deserve support that works for your brain and your body.

Try a few strategies at a time, track what works for you, and remember that progress is better than perfection.

👉 Check out these other recipes & blog posts about nourishing picky eaters:

• ADHD Meals: Easy Ways to Eat a Balanced Diet
• Easy & Adaptable 5-Day ADHD Meal Plan 
• Why Working With an ADHD Dietitian Will Help You Thrive
• ADHD: Forgetting to Eat & What to Do About It

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