How Can You Improve Your Fibre Tolerance?

March 15, 2025

It's New Year's Eve and you have a newfound determination to eat healthier. You start off strong; high fibre porridge for breakfast, a salad for lunch and a bean curry for dinner, only to be left with an uncomfortably bloated stomach.

As we outline in our blog post, fibre is essential for gut health, but eating too much in one go can lead to digestive discomfort, including bloating, gas, and constipation. So how can you eat enough fibre without discomfort? First, you need to understand the different fibre types, and their role in the gut.

What are the different types of fibre?

Fibre isn’t just one thing. It’s a group of plant-based carbohydrates that pass through the digestive system without being fully broken down. There are two main types of fibre, each playing a different role in gut health and digestion.

1. Soluble Fibre: Forms a Gel

As the name suggests, soluble fibre dissolves in water. When it dissolves, it forms a gel-like substance which slows digestion, and 'traps' free sugars and cholesterol, helping to reduce blood sugar spikes and supports heart health by lowering cholesterol. Foods rich in soluble fibre include oats, flaxseeds, chia seeds, apples, and legumes.

2. Insoluble Fibre: Pushes Things Through

Insoluble fibre doesn’t dissolve in water. Instead, it adds bulk to stool and helps food pass more efficiently through the digestive tract, preventing constipation. Think of insoluble fibre as pushing things through. It’s found in whole grains, nuts, seeds, and vegetables like carrots and cauliflower.

Fibre and Our Gut Microbiome (Prebiotics)

Abstract image of gut microbiome Our colon is home to trillions of microbes (the gut microbiome) – most of them are fussy eaters and only consume specific fibre types. These fibre types our gut microbes eat are called ‘prebiotic’ fibres. Prebiotic fibres encourage growth of microbes with potential health benefits.

When microbes digest prebiotic fibre, they produce gas. But our microbiome also pays rent. When our microbes break down prebiotic fibre, they also produce vitamins and substances called short-chain fatty acids, which feed the cells in our gut lining. We feed our bacteria and in turn our bacteria feed us.

Some prebiotic fibre types are highly fermentable - meaning they're broken down quickly by gut microbes. This fast breakdown means gas is also produced quickly. Choosing gentler fibre types, that are fermented more slowly (but still provide the same benefits), is key to maximising the amount of fibre you can eat.

How To Increase Your Fibre Tolerance

Step 1: choose your fibre types.

Choose gentle fibre types that do not ferment quickly (at the start, avoid inulin/chicory root fibre, and foods such as onion and garlic).
Choose a balance of soluble and insoluble fibres.

Step 2: increase fibre gradually

As the gut microbiome is a living ecosystem, your response to fibre is dependent on how much training your gut has had.

Eating lots of fibre at once is like running a marathon without any training - you're destined for discomfort. In the same way marathon runners build up towards 26.2 miles, we can build up our fibre intake towards the recommended 30 grams per day.

As we eat fibre over time, the microbe communities that digest fibre multiply in number. The more of these fibre-digesting microbes you have, the better you can digest fibre, and the more you can eat without experiencing discomfort (and the more benefits you get).

Tips for increasing fibre gradually:

Start small – If you currently eat 10g of fibre per day, don’t jump straight to 30g. Increase by 3–5g per week to give your gut time to adjust
Stay hydrated – Fibre needs water to do its job. Drinking plenty of fluids helps prevent constipation as you increase your intake.
Listen to your body – If you experience bloating or discomfort, slow down the increase and allow your gut more time to adapt.

Step 3: Maintenance

Keep track of your fibre intake. Research has shown how transformational fibre is for our health. Inadvertently falling short is like forgetting to exercise.

The Takeaway

A high-fibre diet supports gut health, blood sugar control, heart health, and regular digestion. But you only get these benefits if you can maintain high fibre intake over time. The way to do that? Increase fibre gradually, ensuring that your digestive system can adjust without discomfort. By understanding the different types of fibre and how they work together, you can make long-term changes that benefit your health in a sustainable way.

Where To Start

Our Fibre Foundation blend contains the gentlest fibre types, which are completely water soluble. Add to water, coffee or yoghurt as part of your daily routine.