What Is Fibre

What’s the fuss about fibre?
What does fibre actually do? Isn’t it just for when you’re constipated? What is fibre in food? Why is fibre important in the diet? How do I get it?

The topic of fibre can be a bit confusing for people, but it’s actually quite simple.


Fibre comes from plant foods – so that’s a good place to start.  When you eat it, it’s only partially digested by the body, meaning it doesn’t get completely absorbed and used for energy like other nutrients. Rather, the undigested bits move through the digestive system, filling us up, cleaning as it goes to remove waste and providing a food source for the good bacteria living in the intestines.


So we now know what fibre does, but there are different types and they are all found in plants in varying amounts.


Soluble fibre


Soluble fibre is mainly found in fruit and vegetables, oats, barley, psyllium, legumes and seeds. Soluble fibre binds with water and turns to a gel in your digestive tract. This sticky gel is able to bind with things such as cholesterol to remove them from the body before they can be reabsorbed. The gel also traps sugars which means that sugars from food enter the blood more slowly. This can help to control blood sugar levels.



Insoluble fibre


Insoluble fibre is mainly found in fruit and vegetable skin, bran, wholemeal products, breakfast cereals and legumes. This type of fibre stays intact to push food through the stomach and the intestines, adding bulk to the stool along the way, helping keep you regular. That’s why insoluble fibre is so important – it’s like a scrubbing brush for your insides!  In fact, the bran of grains is the most concentrated source of fibre and wheat bran is one of the most effective fibres for helping with regularity.


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Fermentable fibre


There is another type of fibre that also makes its way down to the lower gut intact. When it gets there it becomes food for some of the good bacteria living in the colon. This type of fibre is fermented by our gut bacteria and is often referred to as prebiotic fibre. The bacteria use this fibre to produce short chain fatty acids which have a range of different health promoting functions in the gut including helping to protect  the gut wall and providing energy for the cells of the lining. You can find it in beans, grains, green bananas, onions and cooked cold rice and potatoes.



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