Fibre and the Low FODMAP Diet Q&A with Monash University

Fibre & the Low FODMAP Diet Chat Notes

Host: Alana Scott from A Little Bit Yummy

Monash University FODMAP Dietitian: Lyndal Collins


Why is fibre so important?

Fibre is part of all plant-based foods like fruits, vegetables, nuts and seeds, legumes and grains. Our bodies aren’t designed to break down and digest fibre, so the fibre travels through our digestive system, providing food for our gut microbiome and helping form our bowel motions. Fibre impacts the form and consistency of our stools, making it an important consideration when managing constipation and diarrhoea.

Are there different types of fibre?

Fibre can be divided into two main categories: soluble and insoluble. Soluble and insoluble refers to how well the fibre dissolves in water. Soluble fibre dissolves in water and turns gel-like, which can help absorb excess water in the intestines and soften stools, while insoluble fibre doesn’t dissolve and can add more bulk and form to stools. You need a mixture of both types of fibre for good gut health.

Then we have types of fibre like resistant starch and fermentable carbohydrates (aka FODMAPs) that become fuel for our gut microbiome and are broken down by our gut bacteria. Our bacteria ferment these fibre types creating byproducts like short-chain fatty acids that help support our health. This fermentation process also produces gas, which can trigger Irritable Bowel Syndrome (IBS) symptoms in some people. It’s good to note that resistant starch is generally well tolerated by people with IBS.

Why is the low FODMAP diet lower in fibre?

During the first phase of the low FODMAP diet, you reduce your intake of high FODMAP foods and the amount of fermentable fibre in your diet. 

To counteract this fibre reduction, you want to avoid cutting out entire food groups, as you move onto the low FODMAP diet. Instead, focus on swapping out high FODMAP foods for a similar low FODMAP option. 

For example, swap wheat-based pasta for a low FODMAP option like quinoa or wheat/spelt-based sourdough bread. Or swap an apple for a navel orange. By using these swaps, you can find alternative low FODMAP fibre sources. You can find a complete list of low FODMAP and high FODMAPs foods in the Monash University FODMAP Diet App. We’d also recommend working one-on-one with a FODMAP-trained dietitian who can provide personalised advice on adjusting your fibre intake.

How much fibre do you need per day?

The reality is that most people, whether they are on a regular diet or a low FODMAP diet, don’t get enough fibre each day. On average, adults need 25g to 30g of fibre per day, and males often require up to 38g per day although daily fibre recommendations vary slightly from country to country. What we do know is that 25g-30g of fibre per day helps support optimal health and well-being, which can be achieved through eating a range of different low FODMAP foods.

What low FODMAP foods are high in fibre?

There are still lots of low FODMAP foods that contain fibre. Each day, focus on eating a range of plant-based foods, including low FODMAP fruits, vegetables, nuts, seeds, suitable legumes and grains. Check the Monash University FODMAP Diet App for low FODMAP options. 

Boost your fibre intake with seeds. Small amounts of chia seeds, hemp seeds and flax seeds are all low FODMAP options.

Include bran. Avoid wheat bran during the first phase of the diet as this is a high FODMAP food. Instead, include low FODMAP alternatives like rice bran or oat bran for an extra fibre boost.

Enjoy rolled oats for breakfast or in a smoothie. Rolled oats are low FODMAP in ½ cup servings and they are a great way to bring fibre into your low FODMAP diet.

Choose wholegrain options where you can. For example, choose brown rice over white rice or use millet or quinoa when cooking. If you need a quick and easy option, try using the instant rice packets containing pre-cooked brown rice or a mixture of rice and quinoa.

Use resistant starch to your advantage. Resistant starch is a type of fermentable fibre that is slowly fermented by gut bacteria. This slow fermentation means it doesn’t trigger the same gut symptoms as FODMAPs and is well tolerated by most people with IBS. Resistant starch is found in starchy foods (think potatoes, carrots, rice, other grains, pumpkin, sweet potato etc.) that are cooked and cooled before eating. For example, you can create resistant starch by cooking your rice or potato, cooling it in the fridge, and then eating it later. This starch will remain even if you reheat the food. Options like potato salad, fried rice and leftover meals are often great sources of resistant starch.

How do you know if you need a fibre supplement?

Fibre supplements can be helpful if you struggle to get enough fibre from foods or are battling to control symptoms despite being on the low FODMAP diet. There are different types of fibre supplements, so check the information on the package before buying to see if it’s suitable for diarrhoea or constipation. The Monash University FODMAP Diet App has a range of fibre supplements that have been tested and certified as low FODMAP and are suitable for the first phase of the low FODMAP diet. If you need help choosing a fibre supplement, please get in touch with a FODMAP-trained dietitian for extra support.

Extra Resources

If you want to learn more about fibre, check out The Monash University FODMAP team have a range of fibre articles that are a helpful resource:

Research Update: Dietary Fibres and IBS

Getting Enough Fibre

More than FODMAPs: Fermentable Fibre and IBS 

Fibre Supplements and IBS

Dietary Fibre Series: Resistant Starch

Dietary Fibre Series: Insoluble Fibre

Dietary Fibre Series: Prebiotic Fibre

Dietary Fibre Series: Soluble Fibre

You can also find some helpful tips on boosting your fibre intake on

If you want to support the FODMAP work that Monash University is doing, then please download the Monash University FODMAP Diet App from the Apple App Store or Google Play Store. The money you pay for the app goes straight back into low FODMAP research so not only are you helping yourself but you are also supporting your low FODMAP community.

Got a question?

Feel free to leave us a comment and we’ll reply to you as soon as we can.

Final Thoughts

We hope this FODMAP chat session has given you some practical strategies for boosting your fibre intake while on the low FODMAP diet. Just remember that plenty of low FODMAP foods contain fibre and you can include these in your diet. Also, make sure you reintroduce high FODMAP foods after 4-6 weeks to help protect your long-term gut health.

We will be happy to hear your thoughts

Leave a reply

Belli Health
Shopping cart