Fast DietaryTrack rules

During this first two weeks you need to:

• Eat about 150g (5oz) of protein per day, which should come from a portion about the size of your palm at each meal, plus two all-protein snacks per day.
• Eat around 20g of carbohydrates per day. A simple way to work this out is to use a set of measuring cups (a cup holds 250m1/8 fl oz). You should aim to eat approximately 3 cups of low GI vegetables or 2 cups of low GI vegetables and 1/2cup low GI fruit — at least half of which should be eaten raw.
• Get 30 per cent of your daily calorific intake from fats, which may include: olive oil, walnut oil, grapeseed oil, coconut oil, homemade mayonnaise, flaxseed oil, small amounts of butter, small amounts of sour cream
• Drink 8-10 glasses of water daily; you can also drink herbal teas, but avoid alcohol, soft drinks, tea and coffee, because caffeine interferes with ketosis
• Avoid artificial sweeteners, which can stimulate insulin secretion
• Rev up your protein levels by including at least one whey-protein drink per day
• Eat enough — otherwise you may start to burn muscle tissue
• Avoid starchy, carbohydrate-heavy foods such as pasta, bread and potatoes
• Beware of hidden carbohydrates in sauces and dressings
• Check the labels of all foodstuffs and avoid all processed foods
• Not give up!
  

Dietary Q&A

Q. I have been restricting my carbohydrate intake for days now and I have no energy. I thought this plan was supposed to make me feel better, not worse.

A. Your body is adapting to the metabolic conversion of burning fat for energy instead of glucose. This takes about three days in most people, which is why it is usually best to start the diet over a weekend when you are able to relax more. After three days you should see a rise in your energy levels, but if you continue to feel lethargic or unwell, stop the plan and check with your doctor.

Q. Will I get enough fibre on this plan?

A. Fibre is provided by the inclusion of fibrous vegetables and fruit, and is increased if you eat most of these raw. However, if you experience constipation during the initial stages, try adding psyllium husks or psyllium- husk powder to your whey smoothies, because they comprise 100 per cent soluble fibre. Psyllium husks are pure dietary fibre, composed mostly of cellulose. They swell when they come into contact with water and release

a gelatinous mass (mucilage) which passes through the colon and aids easy elimination.

Q. Why does a low-carbohydrate diet cause bad breath?

A. When you are on the Fast-Track Plan and restricting your carbohydrates to around 20g (³/40z) per day, you will be burning ketones, which may cause your breath to smell a little unpleasant. Don't worry, this is easily masked by chewing parsley-oil capsules or by using a natural breath-freshener spray. Make sure that you drink plenty of water because this will help to neutralize the odour.

The carb connection

Carbohydrates are a vital part of the human diet - they are our primary source of energy, and in their natural state they are turned into glucose to provide fuel for all the organs of the body.

THERE ARE THREE MAIN TYPES OF CARBOHYDRATES:

1. Simple sugars, or monosaccharides: glucose (blood sugar), and fructose (fruit sugar)

2. Double sugars, or disaccharides: lactose (milk sugar)

3. Complex carbohydrates, or polysaccharides: starches and cellulose (potatoes, rice, grains and dietary fibre).

The simplest carbohydrate of them all is glucose, which is assimilated immediately by the body. The more complex the carbohydrate's structure, the longer it takes the body to convert it into energy - so 'complex' carbohydrates are the slow burners, because they are higher in more complicated sugars and fibre and thus take longer to break down into energy-giving glucose.

So why are carbs the bad guys?

Even though carbohydrates are a vital component of our overall health, there are certain carbs that serve no nutritional purpose whatsoever, and can even cause us harm if consumed too regularly and in large proportions. They are also the main contributors to the escalating obesity problem. So who are these enemies of our health and weight? They are known as refined carbohydrates.

The problems started the minute we began to process our food and strip out the fibre and nutrients from flour and sugar, to make them look appealingly white. In so doing, we made them nutritionally redundant. Food processing removes magnesium, zinc and chromium from flour and sugar - the three minerals that the body needs to metabolize carbohydrates properly. It also drastically reduces vitamins B₁, B2, B3, calcium and iron.

Junk foods made up of refined flour and sugar, plus nutritionally empty processed fats, colourings, flavourings and preservatives, make up 75 per cent of many people's diets. These so-called 'convenience foods' are 'empty' calories, which hurtle into the bloodstream, play havoc with insulin and blood- sugar levels and actually deplete the body of essential vitamins and minerals that are needed to perform other important bodily functions. Processed foods have also been stripped of their fibre content, which is essential for controlling insulin production and protecting the body against diseases such as diverticulitis and colon cancer.

What kind of carbohydrate?

Athletes often don't know what form of carbohydrate they should be consuming. Does it make a difference if you eat carbohydrate mostly in the form of sugar or should you eat only complex carbohydrates (such as bread, pasta, rice, cereals and potatoes)? Some people regard sugar as 'deadly', while others wouldn't do without it and consider it a necessary part of their diets. Nutritionists advise that sugar and sugary foods should be limited to between 5 and 10 % of total daily energy intake. In other words, a moderate amount of sugar and sugary foods is not considered harmful. The higher the energy content of your diet, the larger the quantity of sugar you can eat. However, sugar and foods containing a large amount of sugar should never take the place of unrefined complex carbohydrates such as wholewheat bread, whole grain cereals and sweetcorn, as these supply other vital nutrients which sugar does not.

Sugar is a useful addition to the diets of athletes who need large amounts of energy, as it supplies a 'calorie-dense' food source. Athletes who take part in triathlons, for example, may find that they simply do not have the time when training two to three times a day to eat the amount of food they need to perform well. By including a small amount of calorie-dense foods - such as those rich in sugar - in their diets, these triathletes are able to fulfill their energy requirements without spending all their free time eating! However, those athletes who try to maintain very low body weights and who consequently eat very little, should obviously keep sugar and foods high in sugar to a minimum.

The fibre factor

Fibre, though not classed as a nutrient, and not actually absorbed by the body, is an important component of our diets, whether we are athletes or sedentary individuals. Found exclusively in plant foods, a low intake of fibre has been linked to various 'Western' diseases. Much of the natural fibre in plant foods is lost in food refinement and this together with a high consumption of animal foods, results in the average Westernized diet being low in fibre. We should all aim to eat at least 30 grams of fibre per day.

Fat

Fat is the other nutrient that is a chief source of energy in our diets. Athletes and the public in general should aim to consume no more than 30% of their total daily energy in the form of fat. Endurance athletes who consume between 60 to 70 % of their energy in the form of carbohydrates, may have to limit their fat intake to 20-25 % of their total calories to allow for those calories obtained from carbohydrates and protein. The main advantage of fat is that it is a very concentrated source of energy (9 calories/37,8 kilojoules per gram). When fat is used as a source of fuel during exercise, it has the advantage of 'sparing' glycogen. A diet high in saturated fat and cholesterol can cause raised blood cholesterol levels, even in athletes who train vigorously, so both should play a limited role in any diet.

What is dietary fibre?

Over the years, many terms have been used to describe the indigestible residue that remains in the digestive tract after all the available nutrients have been absorbed. In fact, when research on the subject began in earnest, one of the first problems the researchers faced was agreement on terminology and definition. It was decided that the terms 'crude fibre', 'roughage' and 'fibre' were inappropriate because some components of dietary fibre are water soluble (see below) and not fibrous or 'rough' at all. The term 'dietary fibre' is however firmly established in the history of nutrition and in the public mind and it was agreed that this should continue to be used.

Hugh Trowel and Denis Burkitt, two British doctors working in East Africa and pioneers in dietary fibre research, recognised early on that fibre comprises a group of substances, all either polysaccharides or lignin. Polysaccharides consist of a multiple grouping of glucose units (as in starch) which are however impossible for humans to digest, while lignin is a coarse, 'woody' compound found in the gritty part of pears and vegetable stalks. Unfortunately, the method they used to determine the quantity of this material also measures a variety of other substances (including some starch) which resist digestion in the small intestine and are only handled by the large intestine later.

Researchers from the Dunn Clinical Nutrition Centre in Cambridge England, developed a new and more appropiate method (the Eglyst method) of analysis, in which starch is completely removed and dietary fibre measured as the non-starch polysaccharides. This has led to a redefinition of dietary fibre as NSP (Non-Starch Polysaccharides). Lignin, although not a polysaccharide, is also regarded as dietary fibre; it is bound to the cell wall and probably contributes to the effects of NSP on body functions. It is however very difficult to measure and amounts present in edible foods are believed to be small.

Soluble vs insoluble fibre

A more practical classification, based on solubility and differences in effects in the body, is that of water soluble and insoluble dietary fibre. Insoluble fibre binds water and has a 'bulking' effect, whereas soluble components are inclined to form gels in water and are therefore also referred to as 'gel-forming' dietary fibre. Interestingly, recent research has shown that water soluble fibre (found in oats, oat bran, dried legumes and some fruit) has a significant cholesterol-lowering effect.

Extraordinary oats

The well-known quip that oats is 'a grain which in England is generally given to horses but in Scotland supports the people' gives no clue as to the diverse nutritional benefits of this cereal product. Firstly, the protein present in oats is of good quality and, coupled as it is with fibre and carbohydrate, it provides a breakfast with a high satiety value at a low price. Foods which - like oats - banish hunger for lengthy periods are particularly useful for schoolchildren, who won't feel the need to dash to the tuckshop at first break!

But this does not mean that oats is strictly for the kids, since the type of fibre which oats contains is of particular significance. Dietary fibre, or roughage, is made up of insoluble fibre (which forms bulk in the digestive tract and plays an important role in promoting peristalsis and preventing constipation), and soluble or gel-forming fibre. The fibre in oats is predominantly of the latter type, which has been shown to play a useful role in lowering blood cholesterol levels. It does this by binding with cholesterol in the digestive tract and preventing its absorption into the bloodstream. In addition, it slows down digestion and, at the same time, the release of glucose into the bloodstream, which is of special benefit to diabetics. Soluble fibre also promotes bacterial action in the digestive tract, helping to prevent constipation, and may well play a role in reducing the risk of bowel cancer.

How fibre affects the body continue...

Appendicitis

Appendicitis is inflammation of the appendix, the small blind-ended tube at the beginning of the large bowel. Although the underlying causes of appendicitis are not clearly understood, there is evidence that regular intake of fibre may prevent the development of the disease.

Hiatus hernia, varicose veins and piles

Many doctors believe that abdominal straining due to constipation encourages the development of conditions such as hiatus hernia (where the top of the stomach is pushed upwards, out of the abdomen and into the thoracic cavity), varicose veins and haemorrhoids (piles). It is often necessary to have surgical treatment for these conditions. Treating constipation with high fibre diets and, as a result, avoiding straining, may prevent these problems and may even reduce the need for more drastic treatment in some cases.

Coronary heart disease (CHD)

Coronary heart disease is the most common cause of death in affluent Western countries (see page 151). A large number of factors influence the development of the disease, of which raised blood cholesterol levels, high blood pressure and hypercoagulability (the tendency of the blood to clot too easily) are probably the most important.

Researchers believe that high-fibre, low fat diets protect against CHD by lowering blood cholesterol and probably also by decreasing blood pressure and the clotting ability of blood. It is especially the water soluble or gel-forming dietary fibres - found in oats, legumes and some fruit and vegetables - which help to lower cholesterol levels. While it should be borne in mind that diet is but one of the many factors which influence the development of CHD, it is also one of the controllable ones.

Diabetes mellitus

There are two forms of diabetes mellitus, a disease characterised by the excretion of glucose (sugar) in the urine (see What is diabetes? on page 175). Both forms are today treated with a high carbohydrate, high fibre, low fat diet. Fibre in the diet normalizes the body's response to dietary carbohydrate (glucose tolerance). A regular high intake of dietary fibre also improves insulin function by increasing the sensitivity of muscle and fat cells to the hormone.

Gallstones

The body manufactures these crystalline substances when the amount of cholesterol in the bile is so high that the bile salts cannot keep it in solution. The stones may block bile ducts between the liver and gall bladder or between the gall bladder and small intestine, resulting in severe pain and even jaundice. As in the case of other diseases of affluence, a number of factors may contribute to the development of gallstones. It has however been shown that high fibre intakes stimulate the production of those bile salts which keep cholesterol in solution, thus decreasing the risk of gallstone formation. Populations who follow high fibre diets have a significantly lower risk of the disease than those on the average refined Western diet.

To what degree is fibre involved?

Although research has proved that dietary fibre has a positive effect on body functions in general, the degree to which it is involved in the risk and development of the above diseases is still unclear. Studies are hampered by the fact that a variety of causes play some role and also because high-fibre diets differ in more than one respect from low-fibre ones. For example, they usually have a lower fat content - especially saturated fatty acids from food of animal origin - and are higher in vitamins and minerals. These factors could add to the beneficial effects seen in people who eat a high-fibre diet.

What is diabetes?

Diabetes is a disorder in which the pancreas cannot produce enough insulin, a hormone which prevents blood sugar levels from rising too high, or in which the insulin that has been produced does not function properly. It does this by helping body cells to take up glucose - either to metabolise to energy or to store as glycogen or fat.

If an individual manufactures too little insulin, there are two possible forms of treatment: The young, more severely affected diabetic can only survive if given daily injections of insulin for the rest of his or her life. However, if diabetes develops at a later age, treatment with pills is usually effective. These pills are not insulin; they are essentially compounds which give the pancreas the necessary stimulus to produce more insulin to cope with the carbohydrate (sugars and starches) which the individual eats. Because sugar causes a dramatic rise in blood sugar levels, diabetics should obviously avoid it in their diets; indeed, they should avoid all unnecessary food in general if they are overweight, as not only is the insulin requirement related to food intake, but excess weight has an aggravating effect on the condition. Obese diabetics who develop the disease in later life can often be treated by diet alone.

A low fat, high fibre intake - which 'dilutes' the contents of the digestive tract - slows down the passage of glucose into the blood stream and hence the elevation of the blood sugar is less dramatic.

How fibre affects the body

The whole subject of food residue is a complicated one because of the variety of indigestible compounds and the different ways in which they influence the digestive and absorption processes in the body. In the simplest terms, dietary fibre acts in the digestive tract by binding or absorbing water and other substances, thus causing 'bulking' of the contents of the gut. It influences the speed with which food moves through the various parts of the digestive tract. However, the ways in which fibre affects digestion, absorption and the movement of food in the digestive tract are diverse, far-reaching and not always well understood. To illustrate this, fibre in the diet may affect blood sugar levels, the production of bile, the transport of cholesterol in the body and your chances of developing colon cancer. It can even affect the hormonal responses to a meal.

A variety of factors influence the effect of a particular fibre or high- fibre food. The chemical composition of the fibre, its particle size, the age of the plant source and methods used in the processing of the food, all affect the physical properties of the fibre. It is these characteristics which account for the different functions of fibre in addition to its main effect of causing in^creased bulk formation in the digestive tract.

Fibre effects are also influenced by the total composition of the meal and the amount of fibre in it. Short-term effects - for example on the blood sugar level - can be seen immediately after a person has eaten a single high-fibre meal. Long-term effects, such as lowering of blood cholesterol levels, occur only after a regular and prolonged intake of fibre. The effect of fibre in the different parts of the digestive tract (stomach, small and large intestine) also differs and may vary between individuals.

Fibre and the diseases of affluence

As already mentioned, research on dietary fibre was initially stimulated by studies which showed that population groups who follow high-fibre diets suffer far less from the 'diseases of affluence' - the medical term used to describe degenerative diseases and disorders which have been linked to a prosperous Western lifestyle. Among these are colon cancer, appendicitis, gall stones, varicose veins and constipation. Their causes are many; what has been established is that a variety of environmental factors, including dietary habits, can trigger these diseases in people who are genetically 'vulnerable' to them. This explains why they tend to run in families and why some people, even though they follow a Western lifestyle, do not develop a particular disease.

Let's look at those diseases which are known to be associated with the amount of fibre in our daily diets:

Constipation

Constipation is probably one of the most common disorders in the world and is also the cause of other diseases (see diverticular disease and colon cancer below.) It can be defined as the relatively slow movement of unduly firm waste matter through the large bowel, which results in the infrequent passing of small, hard and dry stools - often accompanied by straining.

Including enough fibre in your diet prevents constipation in various ways. Firstly, fibre is not digested in the small intestine. It therefore moves to the large bowel where it has a bulking effect, increasing the volume of the bowel content. Because it binds water, fibre prevents the absorption of water from the large bowel to some extent, ensuring that the contents remain large in volume and soft in consistency. Fibre also stimulates the growth of microbes in the large bowel, which contributes to larger, softer stools. The larger volume in the bowel stimulates peristaltic movements and eases the process of defecation so that straining is not necessary. In addition, during the partial fermentation of fibre in the large bowel by microbial enzymes, substances such as methane and hydrogen gasses, water and the short-chain fatty acids are produced. There is now convincing evidence that these acids play an important role in maintaining a healthy bowel.

Diverticular disease

It is now recognised that constipation - and the resultant increase in pressure in the colon (large bowel) because of strained bowel movements - is the underlying cause of diverticular disease. In this disorder, small, blown-out pouches or sac-like swellings (diverticula) form in the wall of the colon and project into the abdominal cavity. Inflammation of these pouches is known as diverticulitis and may cause abdominal discomfort and pain.

Diverticular disease is very common in affluent societies, especially among elderly people. The treatment of constipation with high-fibre diets will not only help prevent the development of the disease, but will also improve - and may even 'cure' - an existing condition.

Colon cancer

Although the role of diet in the development of this disease is still unclear, some scientists believe that high energy and fat and low fibre intakes are important contributing factors (see Cancer - can Your Diet Make the Difference?, page 181). The way in which fibre may protect against colon cancer is probably very complex. It is thought that the rapid movement of a bigger volume through the large bowel shortens the bowel wall's exposure time to substances which may induce cancer (carcinogens).

Because of its bulking and water-binding effects, fibre dilutes the concentration of carcinogens in the gut. It may even bind these substances and help with their excretion in the faeces. New research has showed that butyric acid, one of the short-chain fatty acids produced from fibre fermentation in the large bowel, also protects the bowel against the development of cancer. In addition, changes in colonic pH as a result of the fermentation process may be of importance.

Where do you find dietary fibre?

By definition, only plant foods contain dietary fibre. Published values of fibre in foods vary greatly because of different analysis methods.

Wheat bran (commonly sold under the name of 'digestive bran') has the highest fibre content of all the items mentioned. Because of this, it should be regarded as a food supplement rather than as a food. (If you eat it as a food on its own - for example as a breakfast cereal - your fibre intake could in fact be too high!)

However, as shown above, an important result of the years of research into fibre is the realization that it can be used to lower the risk of some diseases and to treat them.

Can fibre help you lose weight?

Although there is as yet no firm evidence that fibre can be used to control weight problems, it can indirectly be of help if you're trying to cut down on kilojoule intake.

One of the effects of dietary fibre is that it 'dilutes' nutrients and therefore also the energy or kilojoule values of a food. In addition, foods which are rich in it need a good deal of chewing, which not only stimulates secretion of saliva but also means that it takes longer to eat them. In the stomach, insoluble fibre binds water and has a 'bulking' effect, while soluble fibre tends to form gels which slow down the emptying of the stomach contents into the small intestine. The result of these combined effects is that fibre-rich foods make you feel fuller for longer and less likely to head for the refrigerator half an hour after a meal! For this reason, and also to ensure that you get enough vitamins and minerals and won't suffer from constipation, any slimming diet should include ample fibre in the form of unrefined foods.

Effects of fibre in the small intestine

The small intestine is divided into the duodenum, jejenum and ileum and dietary fibre alters a number of functions throughout the area. Whereas refined foods are quickly digested and absorbed in the upper part or duodenum, fibre ensures that the food moves down into the jejenum and ileum, thus changing the site of digestion and absorption. The result is a slower and more prolonged or sustained absorption of several nutrients, which gives the body time to 'process' these nutrients.

In addition to water-binding and bulking effects, some fibre components have the ability to temporarily bind nutrients such as glucose and fats, as well as digestive enzymes, bile acids and possibly some toxic substances. This results in slower digestion of several nutrients and an increased excretion of bile acids - and perhaps also of poisonous substances.

How to increase your fibre intake

Having established that fibre has definite benefits to offer, how can you make sure you get enough of it on a regular basis? Basically, there are three ways of upping your fibre intake, namely:through following a natural high-fibre diet (lots of fruit and vegetables, wholewheat bread, unrefined rice, etc)by eating fibre-enriched foodsby taking fibre extracts or supplements in the form of bran, pills, tablets, powders or granules.

It probably goes without saying that the first option is the healthiest. A natural high-fibre diet in which more unrefined plant foods and less foods of animal origin are eaten, is preferable not only because it ensures adequate intakes of vitamins and minerals, but because it also includes less animal fat - whereas the pill-popping method will merely increase the intake of indigestible fibre.

Eating fibre-enriched products - such as some breakfa^st cereals and home-baked muffins to which bran has been added - will certainly increase fibre intake, but will not necessarily rectify dietary imbalances. This is because most South African recipes for wholewheat home-baked products contain too much fat and sugar, which may improve the flavour but also markedly increases the kilojoules. However, it is possible to cut both the fat and sugar content to healthier levels when baking at home.

Fibre extracts are useful in the treatment of disease. They should only be used for medical reasons and not as foods, and must be taken under the guidance of a physician or dietitian. Insoluble extracts such as bran should always be used in combination with adequate water intake to treat constipation and related diseases. Soluble extracts, such as konjac-glucomannan, pectin or guar gum, are used to lower blood cholesterol levels and to control glucose levels in diabetic patients.

How much is enough?

Recommendations for fibre intake are based on those of developed populations in the past (before the escalation of the diseases of affluence) and on intakes of population groups at low risk for these diseases - such as rural, less developed populations and vegetarians.

On average, affluent Western populations presently consume 10 to 20g total dietary fibre per day; it has been recommended that this should be increased to between 30 and 40g per day. Our own research has shown that white South Africans on a typically Western diet eat approximately 2g total dietary fibre per 1000 kilojoules (kJ) per day - a figure which should be doubled. Based on this recommendation, a fairly active adult woman with a daily energy need of between 8000 and 9000 kJ should take in 32 to 36g dietary fibre per day, while a moderately active adult man with an energy need of 9000 to 11000 kJ should consume 36 to 44g fibre.

The table below shows that you can obtain approximately 40g of total dietary fibre by eating six small to medium portions of wholegrain cereals (which include wholewheat bread, brown rice and unrefined breakfast cereals), one medium portion of legumes (beans, peas, lentils), three medium portions of vegetables and two medium portions of fruit per day.

Foods (and portion sizes) that will provide approximately 40 g total dietary fibre per day

Food	Portion size	Total amount (g)	Dietary fibre (g) -
4 medium slices"wholewheat bread	1 slice: 95 X 90 X 10 mm = 35 g	140	12,5
1 portion All
Bran Flakes	125 ml	25	7,5
1 portion cooked brown rice	125 ml	70	0,9
1 portion cooked dried beans	125 ml	100	7,4
1 portion cooked broccoli	125 ml	75	3,1
1 portion grated raw carrots	125 ml	95	2,4
1 portion mixed raw salad	125 ml	50	0,8
1 medium apple	52 X 66 mm	150	2,6
1 medium orange	65 X 70 mm	180	3,6
TOTAL			40,8

Can you eat too much fibre?

Many fibrous plants contain organic acids that bind minerals such as calcium, magnesium, zinc and iron. Although this has caused some concern in the past, there is no evidence that people who eat natural high-fibre diets (such as vegetarians) have low mineral levels, probably because this type of diet is particularly rich in vitamins and minerals. Including about 40g dietary fibre a day in your diet is regarded as being perfectly safe. However, where caution is necessary is in the taking of fibre extracts.

One of the lesser-known effects of fibre-rich diets is an increase in flatulence. When fibre ferments in the large intestine it produces odourless gases, which are not dangerous to health but can cause concern in some people. (Incidentally, offensive odour is caused by gases which are produced as result of the breakdown of other substances in the large bowel - such as sulphur-containing proteins - which have escaped digestion in the small intestine.)

Fibre extracts - handle with care!

If a natural high-fibre diet does not solve the problem of constipation, try taking not more than three tablespoons (9-12g) of digestive bran, divided into three dosages, on a daily basis. (If you don't like the taste of bran au nature], you can improve the flavour by baking it for three hours at 100 °C.) At the same time, increase your fluid intake to at least two litres per day and decrease excessive fat intake. This ensures adequate hydration of the 'extra' fibre.

Beware of over-enthusiatic dosage with fibre extracts or concentrates, as this can be harmful. As a general guideline, a third of the prescribed dosage should be taken for a week and two thirds for another week before the whole amount is taken.

The 'fibre message'

All in all, then, there is agreement that fibre forms an important part of a healthy, balanced diet. High-fibre diets are easy to follow and inexpensive if natural foods are eaten in their unrefined forms.

Guidance from and education by dietitians, nutritionists and doctors, as well as increased advertising of high-fibre products, have brought the 'fibre message' to some sections of our population.

Sadly, however, in other sections the situation is in reverse. As South Africa's rural black people grow increasingly urbanized, so their diets are becoming lower in fibre and higher in fat - and more and more, the so-called 'diseases of affluence' are being seen among them. For the 'fibre message' to have any significant effect on the health of the majority of our population, it must therefore also reach the very people whose diets once gave them natural protection against the degenerative diseases of Western civilization.

When all is said and done, education is only worthwhile when put into practice. So unless you, the consumer, choose high fibre, unrefined foods in preference to refined ones and unless pressure is put on manufacturers to produce the healthier alternatives, medical research and nutrition education will be of little use. Ultimately it is up to you to make your voice heard and to combat the influences of society, lifelong nutritional habits and perhaps simple apathy, in order to put the fibre message into practice.

Worthwhile Sources of Dietary Fibre (Food Cereals & Fibre rating)

• Bread, brown: Fair
• Bread, wholewheat: Good
• Wheat bran: Excellent
• Pronutro: Excellent
• Kelloggs All Bran Flakes: Excellent
• Kelloggs Cornflakes: Good
• Oats: Good
• Oat bran: Excellent
• Weet-Bix: Good
• Maize meal, white: Fair
• Maize meal, unsifted: Good
• Popcorn, plain: Good
• Rice, brown: Fair
• Ryvita, Ryeking: Good
• Provita: Good