3 Things to Think About BEFORE the Low FODMAP Diet if You've got IBD

If you have IBD and someone has recommended the low FODMAP diet, you're not alone, and you're also not crazy for feeling like it didn't quite fit. 

We hear this all the time in our practice: someone comes to us after trying low FODMAP on their own or on their doctor's recommendation, and it left them feeling overwhelmed, restricted, and honestly no better than when they started.

Before you go all-in on low FODMAP, let's talk about three things we'd want you to consider first, plus what the diet actually is (and isn't) for people with IBD.

What Is the Low FODMAP Diet, Anyway?

FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. It’s basically a category of fermentable carbohydrates. And here's the thing: FODMAPs aren't bad. 

FODMAP’s are fermentable carbohydrates that can increase gas, bloating, diarrhea, or constipation in some people, but they're also food for your gut health and microbiome..

The low FODMAP diet was designed for people with IBS (irritable bowel syndrome, not to be confused with inflammatory bowel disease) to help support symptom relief. 

The Low Fodmap diet is  meant to be conducted with a dietitian, in a structured way through either starting with a low FODMAP way of eating and reintroducing triggers one at a time, or through doing a  “top-down” approach if you're already very restricted. 

Despite the misconception, the low FODMAP diet is only supposed to last about 2 to 6 weeks. Staying low FODMAP for too long can actually hurt your gut microbiome, can increase symptoms and keep you feeling ‘stuck’ on limited foods. 

Unfortunately, this is where most people go wrong. They try low FODMAP without a dietitian, stay on it far longer than intended, and end up more restricted and no closer to relief. 

Plus, some people may not understand that there may be certain portion sizes of higher FODMAP foods they can tolerate OR (and the more likely one in IBD) that their tolerance to many foods has been poor and the gut needed further support and “training” to enjoy fibrous foods. 

Let’s continue to explore what the Low FODMAP diet DOESN’T do for IBD. 

1. It Doesn't Address Inflammation

IBD is a chronic inflammatory disease. That means the core goal of any dietary approach is supporting remission, not just chasing symptom relief. 

Working with an IBD-focused dietitian helps to less food fear and quiet all the online noise and misinformation on diets for IBD too.

Low FODMAP is a symptom-management tool built for IBS. The research does not support that it touches the underlying inflammation that's actually driving your disease.

There is however, some overlap between IBD and IBS. Plenty of people with IBD also have IBS-type symptoms layered on top. 

But in our experience, when people focus on expanding their diet and calming inflammation first, we often see real improvements in the gut microbiome without ever needing to touch FODMAPs.

2. Diet Expansion Should Come First

Here's a question worth sitting with: if you're already restricting a lot of foods (which many people with IBD are), why would you start with a diet that restricts even more?

It sounds backwards, but expanding your diet is usually the better starting point. Your body needs a broad range of foods to respond well to medication and get you to remission faster. 

When you're under-fed and over-restricted, you can get stuck in a frustrating cycle: your body doesn't tolerate foods well, so you eat fewer of them, which makes your gut even less resilient, which makes tolerance worse.

One of the tools we use to break that cycle is prebiotic fiber (and fiber is a much bigger category than most people realize). Soluble fiber can help soak up excess moisture and ease diarrhea over time. It’s one of our mainstay tools! 

Other fermentable fibers get converted into short-chain fatty acids, which may help lower inflammation and reduce symptom sensitivity. These fibers also feed beneficial gut bacteria like Lactobacillus, Bifidobacterium, and Akkermansia. These are all species that tend to run low in people with IBD.

Think of it as building a bridge to better tolerance, rather than avoiding foods altogether. It's not instant, and this is a process that takes time just like building muscles in the gym takes time. It’s always helpful to have dietitian support who can help you navigate it, diet expansion gets at the actual goal: a gut that tolerates more!

3. Know Your Gut and Your Disease

Every IBD case is a little different, and knowing where your disease shows up matters. For example:

• People with Crohn's Disease may have higher rates of lactose intolerance and fructose malabsorption.

• People with Microscopic Colitis may have higher rates of Celiac Disease.

That doesn't mean you automatically have these issues, but it's something worth being mindful of as you work through your care.

Beyond disease-specific patterns, think about your own personal triggers. If loose stools are your main issue, it might be worth looking at high-fat foods, spicy foods, caffeine, or sugar alcohols (yes, that pack of sugar-free gum could be a culprit). 

The goal isn't to eliminate broad categories like all FODMAPs, it's to identify the few specific things that are actually a problem for you. If there are any at all, as tolerance to foods may change over time. 

So What Should You Do Instead?

Start with the foundational stuff: an IBD-friendly way of eating that supports your nutritional needs, paired with tools (like the fibers mentioned above) to reduce symptoms and calm inflammation. That foundation gets you further, faster, than jumping straight into an elimination diet built for a different condition.

And remember, inflammation itself drives a lot of symptom sensitivity. The more you control inflammation and support your gut microbiome over time, the more your tolerance can shift in a good direction, even for foods that used to be triggers.

Low FODMAP isn't the wrong tool for everyone. There are situations where pieces of it come into play. But it's rarely the right place to start for IBD, and it's not something to do without guidance.

If you've tried low FODMAP and felt stuck, overwhelmed, or no better off working with a dietitian who understands IBD specifically can help you find an approach that actually addresses what's going on in your gut.

If you want next steps and a place to get your questions answered, our IBD Nutrition Collective was built for exactly this. 

The IBD Nutrition Collective is an affordable, ongoing membership where you get dietitian-vetted guidance on diet expansion, symptom management, and all the "diet" confusion out there (FODMAP included). Plus, it’s on your own time and at your own pace. Learn more about the IBD Nutrition Collective here.

This post is for educational purposes and isn't a substitute for individualized medical or nutrition advice. Please work with your care team to determine what's right for you.