What?
Fibre is an undigested carbohydrate. It is passed out in stool, as it is not absorbed.
Why?
A diet high in fibre has many benefits, including:
- Preventing constipation (hard stools), which in turn prevents haemorrhoids, fissures (cracks in the anal skin)
- May reduce your risk of colon cancer and polyps
- May reduce blood cholesterol and blood sugars if you have diabetes
- Increases satiation (makes you feel full up)
- May be good for gut bacteria/microbiome
What?
There are two main types of fibre: soluble and insoluble.
1.Insoluble “roughage”: wheat/bran/corn/nuts/grains/skin of vegetables.
-This does not dissolve in liquids and will not form a gel.
-Acts like a sponge to absorb water, bulks stool and ensures things pass quickly though the colon.
-Good for helping with constipation.
-Intestinal bacteria can digest insoluble fibre to a limited degree through fermentation.
2. Soluble fibre: oats/psyllium husk, (some) fruits and veges.
-Dissolves in liquids which can thicken it and may form a gel. It can be broken down by the bacteria that live inside the gut.
-This works to soften, as well as bulk stool. Increasing soluble fibre can help people with diarrhoea (loose stool).
Sometimes it may take time for your gut to become used to increased fibre. You should build up to a full fibre diet over 2-4 weeks. In some people, for example with irritable bowel syndrome (IBS), it can make you pass stool more frequently, or it may cause a lot of wind or bloating or even abdominal pain. In this instance, insoluble fibres are often to blame.
How much?
Around 25-30g per day – 5 handfuls of fruits and veges.
Psyllium Husk/Metamucil:
This is a supplement that can be purchased over the counter and also at the supermarket. One of the main ingredients is psyllium husk (naturally occurring from the plantago ovata plant), which is rich in viscous soluble fiber (70-80%) and also some (but a much smaller amount) of insoluble fibre. In this way, it can absorb and retain water to make loose stools less watery. As this is largely soluble, viscous, gel forming and non-fermentable, it has the best goodies with all aspects covered.
You should take 1-2 teaspoons stirred into a glass of liquid (water or juice).
Important Tips:
- You must keep up fluids with your increased fibre, otherwise it won’t pass. At least 8 cups of water are recommended.
- Foods such as meat, fish, chicken, milk and cheese do not contain fibre.
- The more processed a food is, the lower fibre it will have.
- Different fibres have different effects on different people! Sometimes what works for you may not for others. A trial and error approach with a diet, symptom and bowel diary can be useful.
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