Fibre is not a new phenomenon, all through the ages, in fact as far back as Hypocrites and Marco Polo there has been an awareness that unrefined foods will promote health and longevity. Research has been ongoing, but despite the obvious link between fibre and disease, more and more fibre-depleted foods have found their way into our diets.

Fibre is the structural part of the plant, it is the framework that supports and holds the plant together, it is therefore a component that is only found in foods of plant origin. It is classified as part of the carbohydrate, and often referred to as NSP or non-starch polysaccharide in scientific circles or roughage in layman's terms. It is extremely hardy, you can chew it, swallow it and subject it to stomach acids, yet most of it passes through your body unchanged.

Fibre acts in the bowel to:

Increase faecal weight
Increase colonic transit
Increase frequency of bowel evacuation

There are two major classifications of fibre i.e. soluble and insoluble. Plant foods mostly contain a combination of these two types of fibres. It is easiest to classify all fibre containing foods by that proportion of fibre which is predominant. Latest thinking is that constipation is most benefited by a combination of these 2 fibre types as they each have a different effect on the gut.

Soluble Fibre

Food types which are predominantly high in Soluble fibre are;


Seeds Soluble fibre is effectively broken down by enzyme producing bacteria present in the colon to produce energy and gas. Stools are bulky, said to be attributable to the increase in bacterial mass of the stool. This fibre forms a gel-like substance which can bind to other substances in the gut having additional benefits of lowering cholesterol levels and slowing down the entry of glucose into the blood thereby improving blood sugar control.

Insoluble Fibre

Foods predominantly high in insoluble fibre are:

Roughage foods with skins, husks and peels
Fruit and Vegetables with their skins and pips
Nuts and some Legumes
All other cereals

Insoluble fibre is less easily degraded by colonic bacteria but holds water very effectively (up to 15 times its weight in water) thus contributing to an increase in stool weight. It is this fibre that is often referred to as "natures broom" and has been proven to have many protective effects on the gut from diseases like cancer, IBS, Crohns Disease and many others.

How much do we need ?

Again there is no simple answer to this question, each person's fibre intake needs to be individually assessed for original total fibre content and the contribution of the different fibre sources in your diet needs to be ascertained. This information serves then as a baseline for dietary manipulation. It should be noted that there is a very fine line to be drawn between having the correct amount and overdoing it in terms of fibre intake. Prudent guidelines (i.e. the recommended average for the population) recommend a total fibre intake of 20 - 35gms per day of which 6 - 10.5gms needs to be soluble. I must stress that although these guidelines are prudent they may not be appropriate for you.

How is it achieved

There are 3 ways of increasing your fibre intake:

1. By following a healthy natural high fibre diet; This option is undoubtedly the best, it will ensure that not only are your fibre sources natural and varied but also that your diet will contain the correct balance of other nutrients.

2. By eating fibre-enriched foods; Foods like specially produced high fibre muffins and biscuits will most certainly increase your insoluble fibre intake but will not rectify any other dietary imbalances. Such items are often too high in fat and sugar to be considered part of a healthy balanced diet.

3. By taking fibre extracts or supplements in the form of bran, pills, tablets, powders and granules; Supervised use of bulk forming laxatives can be beneficial in the early stages of dietary manipulation, but should not be viewed as a long-term solution.

The Healthy Natural High Fibre Diet

Fibre is not the cure all, but it is a major component contributing to the intake of a healthy diet and alleviating the symptoms of constipation, Without a properly balanced diet running in combination with a high fibre intake, little will be achieved.

There are many of you who have discovered one or more of the many fad diets on the market. Unfortunately it is very rare that such diets comply with healthy eating guidelines. Although these diets may be high in fibre, when we question the balance of the nutrients and the contribution of the different fibre sources, we are often disappointed.

It has been extensively proven that only the correct combination of soluble and insoluble fibre ensures proper bowel movement. It is also known that the gut bacteria quickly learn to recognise specific fibre sources and within just 2 weeks they increase in efficiency resulting in over degradation of fibre intake and subsequently no, or limited improvement in bowel function.

It is thus of utmost importance that varied fibre sources are consumed.

The recording and analysis of a detailed food diary throughout the process of introduction is important in order to carefully monitor actual fibre intake as well as the balance of other nutrient intake.

Increments in fibre intake need to be very slow but progressive and carefully monitored until the desired effect is achieved. Sudden increases can often lead to unpleasant side effects like pain, cramping, gas and diarrhoea.

Have patience as it takes a few days sometimes a few weeks for a very lazy bowel to adapt and relearn its function with respect to fibre.

In a future update to this web site we will be publishing some tables showing the average fibre content of some commonly used foods.


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