Today, many people on the Internet are urging people to eat a “keto” diet. A keto diet is so high in fat and so low in carbohydrates that it causes people to go into a state of ketosis. Ketosis means that “ketone bodies” have built up in the bloodstream. Ketone bodies are chemicals that are produced by an alternative method of burning fat. Ketosis does not mean that you are losing weight. It really just means that your liver is turning a lot of protein and other noncarbohydrates to sugar. No human society has ever eaten a ketogenic diet. So the long-term safety of ketogenic diets is questionable.