The Fibre Mistake That’s Making Your Bloating Worse

Many of my clients have been told to cut out fibre due to their IBS symptoms or have gradually whittled down their food options until there’s none left. Fibre can be worrying if you’re bloating.

Fibre is often talked about as a single nutrition target, usually measured in grams. But when it comes to gut health, it isn’t only about how much fibre you eat. It’s also about how many different fibres you include.

Your gut microbiome thrives on variety. Different bacteria prefer different fibres, and the wider the range of plant foods you eat, the more likely you are to support a diverse, resilient microbiome.

Let’s take a look at the different types of fibre, why variety matters, common myths that keep people stuck, and how to build fibre diversity gently - especially if you’re prone to IBS symptoms.

Different Types of Fibre Explained

Fibre is the part of plant foods that the body can’t fully digest. Instead, fibre becomes fuel for gut bacteria and helps support bowel regularity, blood sugar balance and digestive comfort.

But not all fibre behaves the same way.

Soluble fibre

Soluble fibre dissolves in water and forms a gel-like texture in the gut. It can help support:

• stool consistency
• feed beneficial gut bacteria
• steadier blood sugar levels
• bind to waste hormones and cholesterol to clear them from the gut

Sources include oats, chia seeds, flaxseed, beans/lentils, apples, pears, carrots and sweet potato.

Insoluble fibre

Insoluble fibre adds bulk and helps move food through the digestive tract.

Sources include wholegrains, nuts and seeds, skins of fruit/veg, kale, cabbage and green beans.

Some people with IBS symptoms find large amounts of insoluble fibre harder to tolerate, especially during flare-ups. This doesn’t mean insoluble fibre is “bad”, but it does mean the type and timing matters.

Resistant starch

Resistant starch reaches the large intestine intact, where gut bacteria ferment it.

Sources include:

• cooked and cooled potatoes
• cooked and cooled rice
• slightly green bananas
• oats
• legumes

Prebiotic fibres

Prebiotics are specific fibres that feed certain beneficial bacteria.

Sources include onions, garlic, leeks, asparagus, chicory and some wholegrains.

If these trigger bloating, it’s often a sign that your gut needs a gentler approach, not that you need to avoid them forever.

Why Diversity Matters More Than Fibre Counts

It’s easy to think of fibre as something you either “hit” or you don’t. But fibre intake isn’t only a numbers game.

Different fibres create different effects in the gut. They support different bacterial species, and those bacteria produce compounds (such as short-chain fatty acids) that influence gut lining integrity and immune signalling.

This is why fibre diversity can be more meaningful for long-term gut health than simply increasing fibre grams quickly.

A useful goal is to aim for:

• a wide range of plant foods across the week
• a mix of wholegrains, vegetables, fruits, nuts, seeds, herbs and spices
• fibre from both soluble and insoluble sources, plus resistant starch when tolerated

This can be done without turning food into a tracking exercise.

If you’d like to understand more about how the microbiome affects whole-body health, you may enjoy my March blog: How Your Gut Microbiome Shapes Hormones and Immunity.

Common Fibre Myths

Myth 1: “If fibre makes me bloated, fibre is the problem.”

Often it’s the speed of increase or the types of fibre being introduced. Rapid changes can increase fermentation quickly, leading to temporary bloating and wind.  This is why slow, steady changes tend to work best.

Or it can be a sign that there is an imbalance on the gut microbiome that needs investigating.

Myth 2: “I need lots of raw salads for good gut health.”

Raw veg can be difficult for some people with IBS symptoms. You can support your gut just as effectively with:

• soups
• stews
• roasted vegetables
• traybakes
• warm grain bowls

In many cases, cooked veg is the most gut-friendly starting point.

Myth 3: “Fibre only matters for constipation.”

Fibre supports far more than gut transit. The microbiome is involved in inflammation regulation, immune resilience and hormone metabolism, which is why gut support can benefit the whole body.

Building Fibre Variety Gently

If you’re prone to bloating or IBS symptoms, the goal is not to overload your gut. The goal is to build tolerance and confidence.

1. Add one new fibre-rich food every few days

For example:

• 1 tbsp ground flaxseed in porridge
• 1 portion of berries
• swapping white rice for cooled brown rice
• adding spinach into a sauce

2. Rotate rather than restrict

Keep your staples, but rotate one or two each week:

• broccoli → green beans
• carrots → beetroot
• oats → barley
• sweet potato → butternut squash

3. Prioritise soluble fibre first

If your gut is reactive, start with gentler fibres:

• oats
• flax/chia
• stewed apple
• carrots
• psyllium (if appropriate and guided)

4. Use small portions of common triggers

Rather than avoiding foods completely, try micro portions:

• 1 tbsp hummus
• spring onion greens instead of onion
• a small serving of lentils in soup