Two types of diet plans which are usually confused with each other are the low calorie diet and the very low calorie diet (VLCD). VLCD should only be undertaken under the strict supervision of a physician. This is also not a diet that you should go for just to loose a few pounds. Its specifically designed for people who are severely overweight to the point of causing obesity related ailments.
A VLCD diet is planned in such a way that the dieter consumes not more than 800 calories per day as opposed to the daily human need of 2200 calories per day. Because of its rigorous nature this diet should never be undertaken for more than 3 to 6 months. Being on this diet for long durations can have drastic health implications. Pregnant women and youngsters below the age of twenty including children should particularly stay away from this diet. It aims at shedding 5 to 6 pound per day. The final goal is to loose almost 50 pounds in the very short duration of 12 weeks.
This diet is specially designed by physicians for people whose Body Mass Index exceeds 30. It is designed keeping in mind the dieters pre existing health conditions if any, the amount of weight to be lost and the impact of this sudden wight loss on the dieters body. The normal procedure in this diet is to avoid normal dietary products and replace them with nutritional supplements which give the body its daily requirement of vitamins and minerals. Regular and delligent physical activity is also a part of this regimen. Apart from this most doctors will recommend psychological interventions such as Cognitive behavioral therapy and self image improvement.
The body usually takes some time to get used to this new diet. Most dieters complain of fatigue, a feeling of weakness, persistent constipation, nausea and diarrhea in the initial stages of the diet. In severe cases the rapid weight loss may also result in the fomation of gallstones. A condition which should be monitored closely.
However if you are just looking at loosing a few pounds you can go for the low calorie diet. This diet restricts the intake of certain high calorie foods. Its aims at bringing down the daily calorie consumption to between 1500 and 1800. If coupled with daily exercise it can give visible results in a few weeks with practically no side effects.