A definition of dieting is the practice of ingesting food in a regulated fashion to achieve or maintain a controlled weight. In most cases the goal is weight loss in those who are overweight or obese. The weight loss diets are generally divided into four categories: low-fat, low-carbohydrate, low-calorie, and very low calorie.

Weight-loss diets restrict the intake of specific foods, or food in general, to reduce body weight. What works to reduce body weight for one person will not necessarily work for another, due to metabolic differences and lifestyle factors. Also, for a variety of reasons, most people find it difficult to maintain significant weight loss over time.

Individuals who are underweight, such as those recovering from anorexia nervosa or starvation, may adopt weight-gain diets. Actors, and people participating in similar activities, may pursue weight loss or gain in order to better portray a particular role.

Receiving adequate nutrition through a well-balanced diet is crucial during childhood and adolescence. In addition, there are some indications that the harmful effects of starvation or extreme dieting during adolescence exceed the expected benefits. Research shows that putting children on starvation or extreme diets can be harmful.

The brain is unable to learn how to correlate taste with nutritional value, which is why such children may consistently overeat later in their life despite adequate nutritional intake. Humans expend energy keeping the vital organs especially the lungs, heart and brain functioning. Except when sleeping, our skeletal muscles are working, typically to maintain upright posture. The average work done just to stay alive is the basal metabolic rate.

Physical exercise is an important complement to dieting in securing weight loss. Aerobic exercise is also an important part of maintaining normal good health, especially the muscular strength of the heart. The energy burnt during physical exercise has only a limited effect on weight loss, since an hour of aerobic exercise for a man in reasonable physical shape would burn about 500 kilocalories, which is equivalent to only 60 grams of fat.

Weight loss typically involves the loss of fat, water and muscle. Overweight people, or people suffering from obesity, typically aim to reduce the percentage of body fat. Muscle loss during weight loss can be restricted by regularly lifting weights (or doing push-ups and other strength-oriented calisthenics).

There is no conclusive evidence that moderately high protein diets in healthy individuals are dangerous. The energy intake from food is limited by the efficiency of digestion and the efficiency of utilization. The efficiency of digestion is largely dependent on the type of food being eaten, while efficiency of utilization is affected by individual factors, including body weight and hormones.

Food provides nutrients from six broad classes: proteins, fats, carbohydrates, vitamins, dietary minerals, and water. Dietary fiber is another food component which influences health even though it is not actually absorbed into the body. Any diet that fails to meet minimum nutritional requirements can threaten general health. If a person is not well enough to be active, weight loss and good quality of life will be unlikely.

Sometimes dieters will ingest excessive amounts of vitamin and mineral supplements. While this is usually harmless, some nutrients are dangerous. Weight-loss diets which manipulate the proportion of macronutrients (low-fat, low-carbohydrate, etc.) have not been found to be more effective than diets which maintain a typical mix of foods with smaller portions and perhaps some substitutions.

Extreme diets may, in some cases, lead to malnutrition. The ideal solution is to keep controll of your weight, to eat right food and to de physical exercise permanent. I recommend you to consult a diet which prooved to be very efficient for a lot of persons with weight problems. Visit my site for more information.

Author's Bio: 

The author is running a website, "Weight Loss Secrets Revealed", where you can find detailed documentation on how to lose weight naturally with no diet. You may find out also interesting things on his blog, "Healthy Mind In Healthy Body". You will receive a lot of tips and gifts related to weight loss and healthy lifestyle.