The theory—which is still being debated—is that your body has to work a little harder to burn ketones than it does glucose, thus boosting your metabolism a bit and resulting in more weight lost. However, if you cut your carb intake to a very low level, your body is forced to look to fat for fuel. Your body’s preferred form of gas for the engine is carbohydrates , because it is easily processed into glucose, which provides muscles and organs with energy. The safety concerns with a keto diet are relatively minor, and easily preventable. However, that isn't to say that the diet is appropriate for absolutely everyone.