A keto diet is an eating plan that focuses on foods that provide a lot of healthful fats, adequate amounts of protein, and very few carbohydrates. The goal is to get more calories from fat than from carbs.The diet works by depleting the body of its sugar reserves. As a result, it will start to break down fat for energy. This results in the production of molecules called ketones that the body uses for fuel. When the body burns fats, it can also lead to weight loss.