There are five variations of the Ketogenic Diet which have been published in medical literature as effective treatments for diseases that have an underlying metabolic dysregulation, such as epilepsy, cancer, and Alzheimer’s. The original Ketogenic Therapy, known as the classic Ketogenic Diet, or classic Keto for short, was designed in 1923 by Dr. Russell Wilder at the Mayo Clinic for the treatment of epilepsy. All Ketogenic Diets are a variation of classic Keto, which is the most strict, seen by it’s ratio of fat to protein and carbs, also called the macronutrient ratio. Classic Keto carries a 4:1 ratio, which means that there are four parts fat for every one part protein and carb. Since fat has a higher caloric content versus protein and carb (fat has 9 calories per gram, while both protein and carb have just 4 calories per gram), 90% of calories come from fat in a classic Ketogenic Diet, while 6% come from protein, and 4% come from carb. The main difference between the five types of Ketogenic Diets is this macronutrient ratio.
All Ketogenic Diets are high in fat, adequate in protein and low in carbohydrates. This combination changes the way energy is used in the body, converting fat into fatty acids and ketones in the liver. When there is an elevated level of ketones in the blood, one is in a state of ketosis, which has a variety of therapeutic benefits for the sick and healthy alike. In addition to the macronutrient ratio, the frequency of eating can influence ketosis. More specifically, a practice called intermittent fasting, which reduces the window of time a person eats throughout the day, can help in obtaining and sustaining ketosis. When the eating window is shortened, the body is forced to access energy from its own fat stores rather than calories directly from the diet.