Fibre is a very important part of a healthy diet, but many high fibre foods are also high in FODMAPs. So how can you get enough fibre on a low FODMAP diet?
Here’s everything you need to know about the importance of dietary fibre and the best high fibre low FODMAP foods you can eat.
What is fibre?
Fibre is the part of plants we humans can’t digest, so it passes through your gut pretty much unchanged.
There are two major types, soluble and insoluble. Their actions are slightly different, but most fibrous foods contain both!
Soluble fibre absorbs water to become a gel that passes through the gut easily and includes fruit, veggies, oat bran, barley, flaxseed, psyllium, dried beans, lentils, peas and soy products.
Insoluble fibre adds bulk and speeds up your bowel movements, and includes wheat, corn, rice bran, skins of fruit and veg, nuts, seeds, dried beans and whole grains.
There is also a third type, not usually thought of as fibre but with a similar effect, called resistant starch. This is the part of starchy foods that resists digestion in the small intestine. It is found in unripe bananas, cereals and grains, potatoes and lentils.
So, you might already know that fibre helps to keep your bowel regular.
You might not know that it also has a whole host of other important body functions.
Eating low FODMAP, high fibre foods like a chia and strawberry pudding will help you reach the recommended amount of fibre you need each day.
Fibre helps to:
- Better manage cholesterol and improve heart health
- Control blood sugar levels
- Keep you full – helping you maintain a healthy weight
- Protect against bowel cancer
- Feed your healthy gut bacteria
Like fruit and veggies, many of us don’t eat enough fibre. Adults should aim for at least 25-30g/day.
You might have noticed that many high-fibre foods are also high in FODMAPs. And a low-FODMAP diet is likely to reduce your intake of many high fibre foods.
Since we know that people struggle to eat enough fibre even when not eating low-FODMAP, it becomes even more important to consider your fibre intake when eating a low-FODMAP diet.
Because fibre keeps our digestive system healthy, not getting enough fibre might even lead you to believe the low FODMAP diet isn’t working for you, or be causing your symptoms.
A note on too much fibre
On the other end of the spectrum – too much fibre can worsen symptoms in some people with IBS. In particular, increased insoluble fibre has been shown to worsen effects of IBS in some people.
Furthermore, some fibre supplements can make things worse, especially if you are already consuming adequate fibre, and if not taken with enough water.
How to get enough fibre while eating low FODMAP
Getting enough fibre on a low FODMAP diet isn’t impossible, you just have to choose the right foods, in the right amounts.
Here are our expert tips from FODMAP specialist dietitian, Chloe MceLeod.
Aim for 3-6 serves of quality low FODMAP grains. These include:
- Brown rice
- Quinoa and quinoa flakes
- Oats and oat bran
- Grainy low FODMAP bread e.g. Alpine Spelt & Sprouted Grain
Aim for at least 5 serves of FODMAP friendly vegetables. These include:
- Brussel sprouts
- Red capsicum
- Green beans
- Oyster mushrooms
- Eggplant… and many more!
Aim for at least 2 serves of FODMAP friendly fruit. These include:
- Kiwi fruit
- Pineapple… and many more!
Hint: Don’t peel your fruit and vegetables unless really necessary – the fibre and nutrients in fruit and veggie skin are better off in your tummy than the bin!
Eat at least 2 serves of low FODMAP fruits a day to get your fibre intake up.
A handful or 30g of FODMAP friendly nuts (such as macadamias, peanuts and pine nuts) per day can do more than boost your fibre intake.
Nuts provide you with healthy fats, protein and can help you maintain a healthy weight. Plus, there are so many great ways to add more nuts to your diet.
You could grab a handful of macadamia nuts on the go, you could add some pine nuts or toasted pumpkin seeds to a salad, or you might even like to add some chia or flax seeds to a smoothie.
5. Canned legumes
Legumes are a source of fibre, but in a low FODMAP diet, most are off limits. Luckily certain canned legumes are safe in small amounts.
- small can (125g) of chickpeas
- ¼ cup (53g) of cooked mung beans
- ¼ cup butter beans and chickpeas
6. Read the label
Compare products to see which is higher in fibre. Chloe recommends choosing products with at least 3g fibre/serve or more.
The final word
This isn’t a comprehensive list – there are plenty of other great sources of fibre that haven’t been listed here.
Check the appropriate FODMAP serve size, or if there is no FODMAP detected in a food, why not check the Australian Dietary Guidelines and get familiar with what the serve size is for the selected food.
It is important to drink plenty of fluid when increasing the fibre content in your diet. If your current intake is low, increase it slowly, because a quick increase may cause abdominal pain and gas.
Reviewed by the healthylife Advisory Board November 2021