Absolutely not, and while ketosis is usually not dangerous (though it can be life-threatening if severe, especially in a diabetic), it is certainly not a particularly healthful state. In addition, one of the major problems with a low-carb diet or even a very low-calorie diet is that they inevitably produce a loss of significant amounts of muscle mass. The muscle is sacrificed in order to provide the dieter with a constant supply of blood sugar. In fact, if you lose weight through fasting or other forms of severe dieting, a significant proportion of the weight loss will be in the form of water (each molecule of glycogen binds six water molecules) and muscle mass. This sort of weight loss will significantly lower your metabolic rate and reduce the primary fat-burning furnace in the body, lean muscle mass, thereby setting you up for serious weight gain later on.
Find out more about this book:Hunger Free Forever: The New Science of Appetite Control