The Importance of Fibre in Our Diet

Why is Fibre important in our diet?


It's no secret that all kinds of nutrients are important in a balanced diet. Sustainable diets should include foods from all the major food groups, including fats, carbs & sugars.


But what about fibre? It’s something we hear about every so often on the tele or in magazines but where can we find it, what does it do, and why is it important for us to eat it?


What is fibre in food?

In normal terms, fibre is a type of indigestible carbohydrate. You might see the word indigestible and wonder what the point of fibre is if it is indigestible, but it’s the very fact that we don’t digest it which makes it so useful!

Most fibre that we eat comes from plants. For example, fruit and vegetables are rich in fibre, as well as beans, lentils, oats, grains, and nuts.

Many foods that contain fibre contain two types – soluble and insoluble. Soluble fibre is able to absorb water and turn into a gel-like substance which can be metabolised by some of the “good” bacteria in your gut, whereas insoluble fibre is mostly made up of cellulose, which remains mostly unchanged all the way through the digestive system (insoluble fibre is also sometimes known as “roughage”).

So why do we need fibre in our diet?

Although we don’t digest fibre, it does help the other foods we eat to move through the digestive system, preventing constipation, promoting good gut health, and even helping with weight management in some cases!

Fibre passes through the digestive tract mostly unchanged, as it isn’t broken down or digested within the small intestine, but diets rich in fibre have also been linked to a reduced risk of certain health conditions such as:

  • Bowel cancer

  • Gallstones

  • IBS

  • Heart disease

  • Diabetes

Soluble fibre also helps to promote the growth of some of the good bacteria in your gut which can have positive effects on the rest of your health. In addition to this, it can also help to stabilise blood glucose levels, which is particularly helpful for those with type 2 diabetes mellitus, or those at risk of developing it.

Insoluble fibre is still valuable and important to include as part of our diet, but this type of fibre is more for keeping things regular. For example, fibre can help to soften stools which can help with constipation, but at the same time, it can also help to bulk up stools and make them firmer if you suffer with constipation fairly often.

Most people are able to eat all different types of fibre in moderation without any adverse effects. However, some people with certain medical conditions such as some types of inflammatory bowel disease may be advised to avoid insoluble fibre as it may worsen their symptoms. If you aren’t sure whether or not you should add more fibre to your diet, you should speak to your doctor or perhaps a dietitian in order to find out what would be best for you.

So how much fibre should I eat every day?

The recommended amount of fibre per day for an adult is around 30g, but unfortunately, UK diets generally only include around 18g of fibre so most of us may need to increase our intake. However, if you’re planning on adding more fibre or roughage to your diet, you should make sure that you do it gradually to avoid any cramping or issues with your stools. Rapidly increasing the amount of fibre that you eat can end up making you feel poorly, so it’s best to make small changes every so often.

Whilst most of us may not be eating the ideal amount of fibre, it’s fairly easy to incorporate more of it into your diet by making small changes or adding an extra portion of fruit or vegetables to a meal each day.

Does fibre make you lose weight?

In some circumstances, and depending on the type, fibre can sometimes help with weight management, as some types of fibre (generally soluble types that you find in peas, beans, lentils and oats) are able to absorb water in the intestine, which can slow down the digestive process and make you feel fuller for longer.

Whilst we wouldn’t recommend eating only fibre, it’s always a good idea to add more of it to your diet if you aren’t already eating the daily recommended amount of 30g. This could mean making a simple bowl of porridge for breakfast, or adding beans or lentils to meals such as curries or pasta sauces.

Another good thing about fibre is that many types can be found fairly inexpensively, and adding it to meals can help it to stretch further, which could help you to save money as well as helping with weight management.

If you increase your fibre intake alongside using liraglutide or semaglutide, then you may be able to maximise the benefits of the medication, as both soluble fibre and the medication can help you to feel satisfied for a long time after a meal, which can also reduce cravings and sudden hunger pangs.

Which foods have soluble fibre?

Soluble fibre means that it can dissolve in water, but it still isn’t digested by our bodies. Most plants contain a mixture of soluble fibre (usually made up of plant pectin) and insoluble fibre (usually made up of cellulose). However, it’s only soluble fibre that can help with slowing down the digestive process which can make you feel more satisfied after eating.