Zanda has a point. That is how the Atkins and Zone diets work, sorta. If you eat only meat it will put your body into a state of
ketosis, which works for weight loss because protein is not the body's preferred form of energy (carbohydrates are), and prolonged absence of sufficient carbs results in the body going into a sort of metabolic shock or starvation mode, even though the amount of calories and fat consumed may be quite high.
This is potentially dangerous for a number of reasons, not the least of which is that high meat diets tend to be full of fat and cholesterol and very little fiber and may contribute the risks of colon cancer and heart disease.