Dietary fibre is one of the most useful nutrients known to mankind. These indigestible components which are found in foods of plant origin, help to keep us regular and prevent constipation, they can lower high blood fat levels, improve blood glucose control in diabetics, and best of all, help people to lose weight.
Why dietary fibre helps with slimming
Certain properties of dietary fibre play a positive role in slimming, namely:
- foods with a high dietary fibre content produce a feeling of fullness or satiety for longer than highly processed foods that have lost most of their dietary fibre content
- a high-fibre content reduces the amount of energy foods contain, e.g. because the dietary fibre in a food like a high-bran cereal is not digested and passes straight through the digestive tract, it will have a lower kilojoule content than a low-fibre cereal
- dietary fibre takes up water and swells in the digestive tract, thus promoting bowel movements in a natural way to prevent constipation which often occurs when you use slimming diets
- high-fibre foods have to be chewed for longer before they can be swallowed and this helps to make slimmers feel less deprived
- foods with a high fibre content can be substituted for foods with a high fat and energy content to prevent slimmers from getting that "starving" feeling which often makes them abandon their diet.
How you can use dietary fibre for slimming
If you want to lose weight, then you need to reduce your energy intake and increase your energy expenditure with exercise. To achieve energy reduction you need to eat less fat, because 1 g of dietary fat supplies 37 kJ of energy compared to 17 kJ per gram for protein and carbohydrates. However, to prevent that ‘starving’ feeling mentioned above, which is fatal for sticking to slimming diets, you need to eat foods that supply enough bulk to make you feel full and satisfied. The answer is to eat plenty of high-fibre foods.
How much dietary fibre?
According to international recommendations, adult diets should contain at least 20 g of dietary fibre a day. Sadly most Western populations don’t get anywhere near this amount. For slimming purposes and other dietary uses of fibre, it is a good idea to eat up to 40 g of dietary fibre a day.
Now, this may sound impossible if you are eating only highly processed foods and avoiding fruit and vegetables. To help you stock up on dietary fibre and change your eating habits to include more fibre for its amazing health properties, let’s take a look at foods that are rich sources of dietary fibre.
The following foods supply more that 3 g of dietary fibre per serving (i.e. 1/2 cup of cereals, cooked vegetables and nuts, one fruit or one slice of bread):
- Hi-fibre Bran and All Bran cereals, fruit and bran cereals, muesli, rye bread, sweet potato, wholewheat pasta, figs, oranges, grapefruit, apples, broccoli, Brussels sprouts, butternut, green beans, brinjal, bananas, cooked beans, lentils and split peas, nuts (should only be eaten in smaller quantities when slimming), samp and beans.
- The following foods supply between 1 and 3 g of dietary fibre per serving, but are also very useful in slimming diets because they are generally eaten in larger quantities, e.g. wholewheat bread, oats porridge, wholewheat and brown bread, potato, wheat biscuits (use low-fat variety), carrots, spinach, beetroot, cabbage, cauliflower.
To ensure that you eat sufficient dietary fibre, especially when you are trying to lose weight, try the following meal suggestions:
Start the day with Hi-fibre Bran cereal plus low-fat milk, a slice of wholewheat toast with a scraping of Lite margarine, and an orange (19 g fibre).
Make yourself a healthy lunch-pack to take along to the office consisting of an apple, carrot salad, 2 slices wholewheat bread with a scraping of Lite margarine and low-fat cottage cheese, a hard boiled egg, or lean meat or fish, or have baked beans on wholewheat toast (11-21 g of dietary fibre - 21 g if you have the baked beans on toast!).
Serve lean meat or fish prepared without added fat, with a selection of high-fibre vegetables and salads (17 g dietary fibre).
Total for day: 47-57 g of dietary fibre without even trying!
If you use these guidelines to increase your dietary fibre intake and reduce your fat intake, you will start losing weight and discover that dietary fibre is really the slimmer’s friend. - Dr I.V. van Heerden, registered dietician.