What does fibre do?
As we have discussed previously, carbohydrates are made up of chains of glucose molecules. When we digest carbohydrates, the body breaks down these chains back into their individual glucose molecules which are then used to provide energy for the body.
Fibre is a carbohydrate, however, fibre does not get broken down into its individual glucose molecules. This is because it has particular types of bonds between the molecules which cannot be broken down by the human digestive system. Instead, it passes through the body.
Fibre is only found in plants and there are two types:
Soluble fibre
Soluble fibre can dissolve in water, and it is found in all plant foods.
It slows the breakdown of other carbohydrates into glucose, and therefore slows the absorption of glucose by the blood. This regulates the blood sugar levels – basically it keeps you feeling fuller for longer.
It also dissolves in water to form a gel-like substance that binds cholesterol to stools, which may help reduce cholesterol levels in the blood.
Insoluble fibre
Insoluble fibre cannot dissolve in water, and is found in grains, and the skins of fruit and vegetables.
It absorbs water, and so helps digestion by drawing water into the stools, making them easier to pass.
It also promotes the growth of certain friendly bacteria which make stools soft and bulky.
This helps waste products pass through the body efficiently, avoiding the build up of toxins that may cause disease.
Ways to increase fibre in the diet
It is clear then that we need to eat fibre, even though it is not absorbed by the body. It does not provide energy to the body in the same way that other carbohydrates do, but it has other useful functions.
Top tips for increasing your fibre intake are:
- Eat more vegetables!
- Eat more fruit, including fruit with skin and seeds, such as apples, pears and berries.
- Choose cereals or cereal products with high fibre content (check out Fibre Plus bars).
- Add canned beans to casseroles.
- Make your crumble topping using rolled oats.
- Choose wholegrain products over white ones (i.e. granary bread instead of white).
