How fast should you expect to lose weight?

Most experts agree that a safe, healthy rate of weight loss is one to 1 to 1½ pounds per week. Modification of eating habits along with regular exercise is the most effective way to lose weight over the long term. It is also the ideal way to ensure that the weight stays off.

Starvation diets may result in rapid weight loss, but this type of weight loss can be unsafe and is almost impossible to maintain for most people. When food intake is severely restricted (below approximately 1,200 calories per day), the body begins to adapt to this state of poor nutrition by reducing its metabolic rate, potentially making it even more difficult to lose weight. It is also possible to experience hunger pangs, bouts of hypoglycemia, headaches, and mood changes from overly stringent dieting. These symptoms can result in binge eating and weight gain. 

Since a highly restrictive diet is almost impossible to maintain for a long time, people who attempt to starve themselves thin often start to gain weight again when they stop dieting and resume their former eating habits.