Why fibre is your friend

Two types of fibre

There are two main types of fibre. Insoluble fibre is sometimes called roughage. It isn't digested and absorbed from your gut, which means it stays in the bowels, helping to bulk out your poos. Wholemeal and wholegrain products, along with wheat bran, beans, pulses, many fruit and vegetables, are high in insoluble fibre.

Soluble fibre dissolves in water to form a gel in your gut. Oats are a particularly good source, and bananas, barley, potatoes, strawberries, plums, peaches, aubergines, apples and pears also contain soluble fibre. In many fruit and vegetables, the skin is high in insoluble fibre while the flesh is a good source of the soluble variety.

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Why should you eat fibre?

It's good for your bowels

There's no question that fibre in your diet is good for your bowels. As well as helping you avoid constipation, fibre can reduce the risk of other bowel problems including painful piles and diverticular disease. It may even reduce your risk of bowel cancer.

It stabilises cholesterol and blood sugar

But we now know that fibre can do much more. Soluble fibre in particular can help reduce your cholesterol and stabilise your blood sugar. This may help reduce your risk of heart disease and even help stave off type 2 diabetes.

It supports a healthy gut

We've also learnt much more in recent years about the importance of the gut microbiome - the trillions of bacteria and other microbes that live naturally in your large bowel. Without them, we wouldn't be able to digest food. Eating more fibre can create a healthy balance between beneficial and harmful bacteria.

About 70% of your immune cells - which help you fight off infection and reduce inflammation in the body - are found in your gut. Your gut is also packed with nerve cells, which communicate with your brain. A healthy gut microbiome has now been found to improve your ability to fight off infection, and your mood.

The wider the range of microbes in your gut, the more healthy it is. Having more friendly bacteria can crowd out germs that cause gut infections and may make it easier for you to keep a healthy weight. Many high-fibre foods act as prebiotics, feeding your healthy bacteria. Probiotic foods - including live yoghurt, sauerkraut, and sourdough - and probiotic supplements can also help boost your friendly bacteria.

Is fibre good or bad for IBS?

Irritable bowel syndrome, or IBS, is a long-term gut condition thought to affect as many as 1 in 5 adults, especially women. It leads to colicky tummy pain, bloating, wind and constipation and/or diarrhoea.

If you have IBS, you may find that eating more insoluble fibre actually makes your symptoms worse. However, gradually upping your intake of soluble fibre may relieve constipation, pain and bloating.

If you have IBS, it's also worth being aware that some high-fibre foods are high in FODMAPS. These are fermentable ingredients which mean the bacteria in your gut create gas as they're digesting them. If you're struggling to increase the fibre in your diet, a dietician may be able to advise you on a low FODMAPS diet.

How to eat more fibre

If you don't have IBS or another bowel condition that causes diarrhoea, there's very little downside - and lots of possible health benefits - to increasing the fibre in your diet.

If your diet has been low in fibre for years, you may want to up your intake gradually to avoid short-term bloating. Over time, your gut will get used to the higher levels of fibre and thank you for it.

At the very least, you should be aiming for at least five portions of fruit and vegetables a day. Fresh, frozen, and tinnned varieties - in natural juices, not sweetened - all count. One portion is the same as:

• One large fruit, like an apple or pear.

• Two smaller fruits, like satsumas or plums.

• Adessert bowl of salad.

• 2-3 tablespoons of vegetables.

With thanks to My Weekly magazine, where this article was originally published.