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DIETING

The term dieting most often refers to the revision of food intakein order to lose weight. Diets are also observed for a wide range of medical reasons or to accord with dietary lawsor ethical positions such as vegetarianism. In the United States and other developed nations where obesityis a common metabolic problem, the promotion of weight-loss programshas become a large enterprise. This interest in dieting is caused in part by a cultural emphasis on slimness,but obesity is considered a genuine medical hazardthat puts people at risk for cardiovascular problems,diabetes, and other disorders.

People often find diets hard to maintain,in part because they may have unrealistic expectations about how quickly they can lose weight. They may blame the diet itself and try another one. Many fat diets are unhealthy and even dangerous if followed for any length of time. Proper weight-loss diets observe good nutritional practices and balanced food intake, including the recommended daily regimens of vitamins and minerals.

General Guidelines

In nutritional science, food energy is spoken of in terms of a heat unit, the calorie (actually the kilocalorie). The only sources of calories are carbohydrates, proteins, fats, and alcohol. If the number of calories taken in greatly exceeds the number used, the excess is stored as fat and obesity results. With proper dieting and exercise the fat stores in the body will supply some of the dieter's energy needs while maintaining good health. For most people, the recommended rate of weight loss is about 0.7 to 0.9 kg (1,5 to 2 Lb) per week. This can be achieved on diets limited to 1,200—1,500 calories a day for women and 1,500 — 2,000 calories a day for men; calorie needs of children vary greatly, and their rates of weight loss should be prescribed by a physician. The most sensible approach to weight loss is to begin with a medical check-upto make certain that no special health problems exist and to get a diet and exercise prescription from a physician. The diets that are acceptable to the medical establishment are those in which fewer calories are eaten and exercise is increased. This is called the calorie-balanced approach to dieting. Although some diets may place more emphasis on calorie reductionand others on increased exercise, all of them emphasize the importance of good nutrition and maintaining a balance of proteins, carbohydrates, and fats.

Diet Problems

There is a number of problems associated with dieting. Research, has shown that in many cases, diets are successful only on a temporary basis - most dieters regain the weight,plus more, within two years.

Many of these dieters try to lose the weight again, a cycle called yo-yo dieting,There has been controversy about the yo­yo dieting's effects on the body, with some studies indicating that it causes problems with metabolism and heart disease. However, a 1994 study disagreed, finding no such effects.

Another problem is that many of the commercially offered diets emphasize one dietary element at the expense of others; such practices present health problems. Low-carbohydrate diets, for example, restrict the amount of bread, sugar, and grains while maintaining a normal amount of protein and fats. Most of the initially rapid weight loss from such programs is from the body ridding itself ofwater and salt. A plateau is reached after one or two weeks, and no additional weight is lost for several weeks thereafter. Most people experience fatigue, hypertension(low blood pressure), and dizzinessafter only a few days on such diets, which are adaptations of an older American Diabetes Association diabetes diet.

High-protein diets virtually eliminate carbohydrates and fats. Because carbohydrates are the most readily available source of energy, an all-protein diet forces the body to burn stored fat and protein. High protein diets, requiring complete elimination of carbohydrates, can be used only for the short period of time and are dangerous for anyone with diabetes, kidney disorders, or other medical problems. Diets high in fats and cholesterol are hazardous for persons with arteriosclerosis and heart disease. This type of diet also causes diarrhea, vitamin loss, hypertension, dehydration, and kidney irritation. Numerous diets emphasize one food, such as rice, grapefruit, ice cream, or yoghurt. These are not nutritionally balanced and require vitamin and mineral supplements. Formula diets in liquid or powder form, which typically supply from 900 to 1200 calories per day, claim to contain the recommended daily allowances of nutrients; serious health problems have sometimes been reported with their use. Non-prescription drugs called anorexics are supposed to suppress the appetite but have little effect by themselves and must be used with a sensible diet plan: they too may be harmful. As for starvation dieting, this dangerous practice should be attempted – if at all- only under strict medical supervision.

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1. Work out a dieting programme, mentioning meals, which should be taken.

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