Our bodies were not designed to survive healthily for very long on a diet composed of any one type of food. Not only would it be monotonous, if would also fail to provide the range of nutrients that the body requires for health. These are proteins, fats, carbohydrates, vitamins, minerals, and fluid. Whilst we are sure you have come across these terms before, we didn’t think that the ebook would be complete without laying out the bones of a balanced diet.

What’s Essential?

Proteins are the building-blocks of the body. Tissues, such muscle, heart, liver, kidneys, and most other organs, are rich in protein. Skin, bones and hair also contain certain amounts of protein, which contributes to their structure. The main role of proteins, however, is to perform the functions of each individual cell. Thus protein is necessary for the ovaries and thyroid to produce hormones, for the kidneys to make urine, for muscles to exercise, and so forth. If a large amount of protein is energy purposes, and during starvation, protein is taken from the muscles of the body and used as fuel supply. This tends to slow down the body’s metabolic rate, and for this reason weight-loss diets should have plenty of protein. On average for every one stone (14 pounds/6.5kg) of body weight, we require a daily intake of some 5 grams of protein (about half an egg.) this is essential to keep the body healthy.

Carbohydrates come in a variety of different forms, all of which are best regarded as sources of energy. The simplest forms of carbohydrates in our diet are glucose and fructose. These are single sugar units, and fructose is found particularly in high amounts in fruit; hence its name, which means fruit sugar. Fructose and glucose can be joined together to make sucrose or table sugar, normally prepared from sugar cane or sugar beet. Milk contains yet another type of sugar called lactose, which itself is composed of two single units of sugar: glucose and galactose.

So much for the simple carbohydrates. The complex carbohydrates, which are found in vegetables, cereals and to a lesser degree in fruits, are composed of numerous sugar units joined together in a complex way. These have to be broken down by the digestive system before they are absorbed as single units of mainly glucose and fructose. Complex carbohydrates are desirable for three reasons: they are slowly digested and release their energy at a steadier rate.

Foods rich in complex carbohydrates are also rich in vitamins and minerals, which are essential for the metabolism of sugar and the steady release of its energy. Such foods are also high in fibre, high intakes of which are associated with many health benefits.

Refined carbohydrates, such as sucrose and pure glucose, may be a convenient source of quick energy, but they are all too easily consumed to excess, and thus may lead to obesity.

Fats are a major source of energy in the diet, and provide twice as many calories as protein or carbohydrates for the same amount of weight. In developed countries, fat intake has increased at the expense of a reduction in complex carbohydrates. In order to lose weight, we almost always have to cut down on fat intake, but some fats are essential, just as vitamins and minerals are. These are the polyunsaturated fats, which are derived mainly from sun-flower, safflower and rappelled oils, vegetables, nuts, seeds and some fish.

Foods of animal origin, e.g. lard, dripping, butter, milk, cream, cheese, and meat, and some vegetable oils, notably palm oil and coconut oil, are rich in saturated fats. These are not essential, and have the undesirable effect of stimulating the liver to produce more cholesterol, and raising its level in the blood. Both saturated and polyunsaturated fats contain the same amount of calories.