But many dairy products are not great choices while on the keto diet because they are too high in carbs. In this respect, our paleolithic ancestors would have naturally had cycles of ketosis because ketosis is what happens when the body runs on fats for fuel rather than carbohydrates or protein. Consuming a healthy, biologically appropriate diet will get you to a good body composition —meaning the fat to lean tissue ratio, which is what we are talking about when we talk about weight loss.