Yeah, the problem with all-meat diets, as with any food-specific diet, is finding the nutrients and energy you need. That being said, all of the nutrients you need are not in meat. You need lots of vegetables, some dairy (like cheese), nuts, eggs and some fruit too. You also need some carbohydrates. The good thing about this kind of diet is that it's NATURAL!! We evolved over hundreds of thousands of years to eat meats and greens! Humans have only been farming for a very small fraction of that time, so grains are, for the most part, not something we're built to eat. Atleast that's the way I see it. Make sense, doesn't it?