Very low-calorie diets are not without risk and should be pursued only under medical supervision. Unsupervised very low-calorie diets can deprive you of important nutrients and are potentially dangerous. Fad diets rarely have any permanent effect. Sudden and radical changes in your eating patterns are difficult to sustain over time. To lose weight safely and keep it off requires long-term changes in daily eating and exercise habits.
Many experts recommend a goal of losing about a pound a week.
A modest reduction of 500 calories per day will achieve this goal, since a total reduction of 3,500 calories is required to lose a pound of fat. An important way to lower your calorie intake is to learn and practice healthy eating habits. The FDA has seized millions of these products from manufacturers and promoters. Not only is the claim unproven, but users have complained of nausea, vomiting, diarrhea, and stomach pains. The FTC has brought legal action against several marketers of these pills.