Eating enough fibre

What is dietary fibre?

Dietary fibre is the part of plant foods that passes through our stomach and small intestine without digestion. In our large intestine, dietary fibre can feed our gut bacteria.

Types of dietary fibre

There are many different types of fibre that makeup plant foods. They have different roles in the gut, such as:

• Creating a gel - this fibre thickens when mixed with liquids which makes stools bulkier, softer and easier to pass
• Adding bulk - this fibre increases the weight/size of stool, normalising how quickly or slowly stools pass through our intestine (helpful in diarrhoea and constipation)
• Fermenting - this fibre feeds the “bugs” in our gut. This may encourage the growth of “good bacteria”, which can produce substances that benefit bowel health and strengthen our immune system.

Health benefits of dietary fibre

• Reduce constipation (makes stools softer and easier to pass regularly)
• Reduce diarrhoea (firms up loose stools)
• Reduce blood glucose and cholesterol
• Reduce risk of some diseases (e.g. cardiovascular disease, bowel cancer)
• Fill us up at mealtimes
• Improve our bowel health
• Strengthen our immune system

Foods rich in dietary fibre

Fibre is found only in plant foods. These include fruit, vegetables, nuts, seeds, legumes, lentils and whole grains. By contrast, foods such as meat, chicken, fish, eggs and dairy do not contain any fibre.

The best way to get all the health benefits of dietary fibre is by including a wide range of plant foods in your diet. One way of doing this is by aiming to include 30 different plant foods each week. Try to eat a wide range of colours, textures and flavours each day. Choosing seasonal produce is also a good idea as this is cheaper and gives you more variety over the year.

Eating enough fibre on a low FODMAP diet

Some high FODMAP foods are also high in fibre. This means that some people struggle to eat enough fibre on a low FODMAP diet. Tips to eat enough fibre while following a low FODMAP diet include:

• Snack on foods such as fruit (e.g. kiwi fruit, berries), a handful of nuts (e.g. almonds, walnuts) or popcorn
• Include vegetables at breakfast (e.g. grilled mushrooms/tomato on toast), lunch (e.g. soup/salad) and dinner (e.g. roasted/gilled/stir-fried vegetables with your meal)
• Add a sprinkle of chopped nuts or seeds to yoghurts, salads, porridge or stir-fry
• Add canned lentils to a bolognaise, casserole or curry
• Swap low fibre foods for high fibre options e.g.
  • white rice → brown rice / quinoa
  • Low fibre cereal (e.g. rice bubbles) → oats, quinoa flakes
  • potato chips → popcorn
  • butter/margarine → avocado

Should I try a fibre supplement?

Some people struggle to eat enough fibre and can benefit from a daily fibre supplement. An experienced dietitian will help you to decide if you need a daily fibre supplement and advise you on the most suitable type and dose.