The “ketogenic diet” has recently become a more popular dietary regime. In short, the ketogenic diet is a system of eating where most calories come from dietary fat and very little come from carbohydrates. Eating this way will switch the body from glucose metabolism to “fat” metabolism for energy, and this fat metabolism state is called ketosis.
As you may know, carbs in the diet are the source of glucose which is used in the body as energy. When there are limited amounts of carbs available, blood glucose levels are so low that the body turns to breaking down adipose tissue into ketone bodies which are used for energy.
Before we get into the nitty gritty, I want to first wipe away any misconceptions you may have about “fat.” Firstly, “fat” in the body and “fat” in foods are very different. I will refer to fat in the body as adipose tissue and fat in foods as dietary fat. Many people believe that eating fat will turn into fat in the body, but they could not be more mistaken.
To enter a state of ketosis on the ketogenic diet requires the diet to be 60-70% dietary fat, 20-30% protein, and 50g carbs or less per day. It takes about three weeks of this strict eating for the body to actually adapt and turn to ketosis.
There are many benefits to this type of eating. This diet is the best of the best for stubborn adipose tissue and weight loss. During the first experimentations with the ketogenic diet, researchers found that those in ketosis burned adipose tissue at twice the rate than was believed to be the human limit.
We all know how addicting sugar and carbs can be. Being on the ketogenic diet may help the brain escape this sugar dependency. Moreover, most people’s diets are high carb, so the body often becomes inefficient at using its fat tissue; a problem the ketogenic diet may fix.
There are some drawbacks. Eating this way is quite a big commitment and takes a lot of planning. It takes around three weeks of eating 50g carbs or less per day for the body to even switch into a state of ketosis. Even one day higher than the limit of 50g carbs/day will throw the body back into glucose metabolism. 50g of carbs or less means utilizing vegetables as the only carbs eaten—very minimal fruit would fit into this 50g.
This diet is great for weight lifters because it supports muscle building. For endurance athletes, the ketogenic diet may be an optimal choice of eating because the body’s main source of energy is the adipose tissue, so it ultimately improves the anaerobic threshold and increases the time before “bonking”.