Are Mushrooms Low FODMAP? Well, that depends…

Written by Amy Vaughan, RD
Reviewed by Gina Giebner, RD

Are mushrooms low FODMAP? Mushrooms are often assumed a food to avoid when you’re following a low FODMAP diet – but is that always necessary? The truth is, it depends. Some types of mushrooms are high in a group of fermentable carbohydrates called polyols, which can trigger bloating, gas, and general digestive discomfort in people with irritable bowel syndrome (IBS).¹ But others are surprisingly gut-friendly, especially in the right portion sizes.

And beyond FODMAPs? They’re full of texture and flavour (hello, umami) and a brilliant way to add variety to plant-based meals.^2,3 If mushrooms are a favourite of yours, it’s worth exploring how they might still have a place on your plate. Mushrooms are nutrient-dense and naturally low in fat, sugar, and sodium. They offer key B vitamins like thiamine (B1), pantothenic acid (B5), and B12, plus important minerals like calcium, iron, potassium, and zinc.³ They also contain bioactive compounds like β-glucans and phenolics, which may support immune function and protect against inflammation, oxidative stress, and chronic disease.³

In this post, we’ll break down which mushrooms are low FODMAP, which ones to be cautious with, and how to enjoy them without disrupting your gut balance.

Why Mushrooms Can Be Tricky on a Low FODMAP Diet

Mushrooms are one of the few plant-based foods that naturally contain polyols, specifically a type called mannitol.¹ Polyols are part of the “P” in FODMAP, and they can be tricky for people with IBS because they draw water into the gut and ferment quickly, often leading to symptoms like flatulence, bloating, discomfort, or loose stools.⁴

But here’s the good news: not all mushrooms contain the same amount of mannitol. Some are high FODMAP even in small servings, while others are low enough to include in moderate portions without triggering symptoms.

As with many FODMAP-containing foods, it’s about understanding which types are more likely to cause symptoms, and how much of them your gut can handle. With the right information (and a bit of trial and error), mushrooms don’t have to be off the table.

We’ve got plenty of articles on Low FODMAPs you might enjoy exploring, including the following: Low Fodmap Breakfast Ideas: Includes 12 Recipes To Try, 7 Low FODMAP Plant-Based Protein Sources – Dietitian Approved, Are Hemp Seeds Low FODMAP?

Which Mushrooms Are Low FODMAP?

Not all mushrooms are created equal when it comes to FODMAPs. Some are naturally lower in polyols, while others are best limited, especially during the elimination phase of the low FODMAP diet.

Here’s a quick guide to help you navigate what’s likely to be well tolerated, and what might be worth steering clear of (at least for now):

These serving sizes can help guide what’s safe to try during elimination versus what to save for reintroduction. Portion size is key, what’s low FODMAP in small amounts can easily become high FODMAP in larger servings.

As you can see there are mushroom options that are naturally low FODMAP in generous portions, like oyster, chestnut, and canned button mushrooms, so you can still enjoy their unique texture and flavour without triggering symptoms.⁵

Looking for an easy way to put this into practice? This low FODMAP creamy mushroom pasta by Georgeats is packed with flavour and shows how to use FODMAP-friendly mushrooms in a simple, satisfying meal.

Where do functional mushrooms fit in?

Functional mushroom extracts like powders, coffee, or capsules made from reishi, lion’s mane, or shiitake are highly concentrated.³ Even in small amounts, they may still contain FODMAPs, especially if made from high-FODMAP varieties like shiitake. The only extract currently tested by Monash University is lion’s mane powder, which is considered low FODMAP in servings up to 2g.⁵ Beyond that, the FODMAP content of most extracts remains unknown. And because they’re concentrated, they may pack more of a FODMAP punch than expected. If you’re using mushroom supplements and following a low FODMAP diet, check the ingredient list carefully and speak with your dietitian for personalised guidance.

A gut-friendly guide to eating mushrooms

Mushrooms aren’t necessarily off-limits if you have IBS or are following the low FODMAP diet, you just need to know how to make them work for you. Here are a few ways to do that without upsetting your gut.

• Try fresh oyster mushrooms: They’re naturally low in mannitol and are generally well tolerated in moderate portions (up to 75g).⁵
• Use canned button mushrooms and make sure to drain and rinse them well: Most of the FODMAPs in canned mushrooms leach into the brine, so draining is essential. But giving them a good rinse under cold water helps reduce the load even further.⁵ 
• Stick to recommended portion sizes to start: Even low FODMAP mushrooms can become high FODMAP if you go over the recommended amount, so it’s worth measuring them out, especially during the elimination phase.⁶
• Be mindful of FODMAP stacking: If you’re eating other foods that contain polyols (like cauliflower, sweetcorn, or apples), even a small serve of mushrooms could tip things over your personal threshold.⁷
• Work with a dietitian to reintroduce mushrooms (and other foods) confidently: Everyone’s gut is different, some people may find they can tolerate certain mushrooms (or portion sizes) more than expected once reintroduction begins.

Putting mushrooms back on your plate

If you’ve been avoiding mushrooms because of their FODMAP content, we have good news. Some varieties, like oyster, chestnut, and canned button mushrooms, can be enjoyed in generous portions, even during elimination.⁵ With options like these on your side, it’s worth rethinking the idea that mushrooms are off-limits. And for those that are higher in FODMAPs? Many people find they can tolerate more than expected with a personalised approach. Others might be better saved for reintroduction. And that’s the key: with the right guidance, many people find they can tolerate far more than they first thought.

Working with our specialist dietitians can help you navigate that process so you’re not just cutting foods out, but slowly and safely bringing them back in. Your gut is unique, and your version of an IBS-friendly diet should be, too. And remember: the low FODMAP diet is a short-term tool, not a forever plan³.

Our specialist gut health dietitians can help you personalise your approach, expand your food choices, and feel more confident with each phase of the process – book in for a discovery call!

References

1. Jiang, C., Duan, X., Lin, L., Wu, W., Li, X., Zeng, Z., Luo, Q. and Liu, Y. (2023). A review on the edible mushroom as a source of special flavor: Flavor categories, influencing factors, and challenges. Food frontiers. [online] Available: https://doi.org/10.1002/fft2.263
2. Bell, V., Silva, C.R.P.G., Guina, J. and Fernandes, T.H. (2022). Mushrooms as future generation healthy foods. Frontiers in Nutrition, 9. [online] Available: https://doi.org/10.3389/fnut.2022.1050099
3. De, S., Chawla, P., Dhull, S.B., Goksen, G., Arjun, A.D. and Bains, A. (2025). Techno‐Functional Biochemical Analysis and Food Applications of Edible Mushroom Powder. Journal of Food Biochemistry, 2025(1). [online] Available: https://doi.org/10.1155/jfbc/2888689
4. Lenhart, A. and Chey, W.D. (2017). A Systematic Review of the Effects of Polyols on Gastrointestinal Health and Irritable Bowel Syndrome. Advances in Nutrition, [online] 8(4), pp.587–596. [online] Available: https://doi.org/10.3945/an.117.015560.
5. Monash University. Monash FODMAP Diet. Version 4.0.6 [iOS mobile application]. Available: https://www.monashfodmap.com/ibs-central/i-have-ibs/get-the-app/
6. Monash University. (2018). Understanding the traffic lights in the Monash FODMAP Diet App. [online] Available: https://www.monashfodmap.com/blog/traffic-light-system/
7. Monash University (2022). FODMAP Stacking Explained. [online] Available: https://monashfodmap.com/blog/fodmap-stacking-explained/