All of us are buying less basic or generic food in favour of convenience products. 10 years ago we were buying 16 per cent more unprocessed meat. Sales of fresh and frozen fish fell by 13 per cent between 1991 and 1992 — in favour of cooked varieties. We are also buying fewer fresh vegetables, other than those that can be eaten immediately, a fall of over 20 per cent during the past decade. Frozen vegetables, however, increased their sales by 7 per cent in 1992; and sales of frozen ready meals increased by 17 per cent. Only three per cent of us were vegetarians in 1986; that had doubled to 6 per cent by 1991 and 10 per cent of the population may have abandoned meat by the end of the decade.

Changed lifestyles mean that both sides of the ‘calorie-controlled diet’ equation — our energy needs as a result of how we spend our day and our energy intake in the form of what we eat — have undergone profound alterations.

Although people who diet normally wish to reduce their weight, some people need to gain weight — this information is for them as well.


Calorie Counting


All foods have a calorific value and contribute to keeping the
body going. A high calorific value means that there is a lot of
energy locked up in the food which the body can convert.

One calorie is the amount of heat required to raise the temperature of 1 gram of water by 1 degree centigrade.

The principles of the calorie-controlled diet are perfectly
simple: Using the main Calorie Counter tables you identify the
energy content of the food you eat. If you take in more food energy than your body burns up, some of it will be evacuated when you use the toilet, but some will stay in your body, usually deposited as fat, and your weight will increase. If you don’t eat enough of the right sort of energy giving food, then your body will have to use up existing stores of fat. Essentially, that’s what you make your body do when you go on a slimming diet.

First, there is of course more to food than its energy content. We require substantial amounts of water. Besides water, we also require a wide range of vitamins and minerals. We also need a collection of proteins. We must also have fibre (strictly speaking, fibre isn’t a food because it is not ingested, however fibre is essential for the alimentary canal to function properly) So: you can’t base a diet solely on calorie counting.

One of the many dangers of crash weight-loss courses is that the body ends up lacking essential nutrients. Whatever your plans, you must have what nutritionists call a well-balanced diet’. In general terms, this means eating a broad range of fresh foods, with an emphasis on uncooked (or only slightly cooked) fruit and vegetables. These foods should bring you all the proteins, vitamins and minerals your body needs.

The energy-supplying ingredients in food are: proteins,
carbohydrates and fats.

Protein is made up of amino acids. There are 20 key amino acids. Eight of these are called essential amino acids because their nutrients cannot be manufactured by the body and must come from the outside, from our diet. Excess protein taken in is burned for energy. One gram of protein burned for its energy contains four calories.


Carbohydrate


Carbohydrates are the body’s main source of energy. Other nutrients must be converted to carbohydrate before the body can use them. Carbohydrates provide glucose ready for the body to burn. But the body can also convert fat and protein to glucose, and will do so if the need arises. Carbohydrates can be classed as simple or complex. Examples of simple carbohydrates are glucose, fructose (found in fruit), sucrose and lactose (found in milk).

Complex carbohydrates are long chains of glucose molecules, usually referred to as starch. These take much longer to digest, because the body has to take them apart, one molecule at a time. One gram of carbohydrate contains four calories of energy, and people require a
minimum of about 100 grams a day.

Fats


Fats are a concentrated energy source, yielding nine calories per gram, compared to the  four per gram found in protein and carbohydrate. Nutritionally, fats exist in three different chemical states: saturated, monounsaturated and poly-unsaturated. Generally, the more unsaturated a given fatty acid, the more liquid the fat is. Saturated fats are associated with heart disease because fatty deposits can build up in the body’s blood vessels and slow down blood flow; poly-unsaturates, being more liquid, are less likely to do this.

We refer to ‘fats’ as those that are solid at room temperature, and ‘oils’ as those that are liquid. Fat that comes from animals is almost always a ‘fat’; that which come from plants is almost always an ‘oil’.