What is the Ketogenic (“Keto”) Diet?
The purpose of the ketogenic diet is to force the body into a fat burning state, burning fats instead of carbohydrates for fuel. Those who follow it eat a diet containing high amounts of fat, moderate amounts of protein and low levels of carbohydrates.
Through this breakdown of macronutrients, you’re able to change how the body uses energy. To fully understand the process, it’s important to grasp how the body uses energy in the first place.
How to Switch From Burning Carbs to Burning Fat
When you eat a diet rich in carbohydrates, your body converts those carbs into glucose. This causes an “insulin spike,” as insulin carries the glucose to your bloodstream for energy. Glucose is the preferred energy source of the body. When glucose is present, your body will burn it before burning fat.
A ketogenic diet lowers your carb intake. In turn, your glucose levels lower, so your body can’t convert it to energy. This sends your body into a state known as ketosis, the basis of a ketogenic diet.
Ketosis transforms your body into a fat-burning machine, burning fat (not carbs) for fuel. Specifically, the liver converts fatty acids in your body into ketone bodies, or ketones. This becomes your body’s new energy source. When you increase your fat intake, your body responds by becoming “keto-adaptive,” or more efficient at burning fat.
Ketosis is a natural survival function of the body. It helps your body function on fat when food is not readily available. Similarly, the keto diet focuses on “starving” the body of carbohydrates, transforming the body into a fat-burning state and supplementing with optimal nutrition.
But Isn’t Fat Bad? Busting the “Fat Makes You Fat” Myth
Nutrition data from the 1970s told us saturated fats are bad, causing the United States to enter the era of low fat. During this time, obesity in America soared while consumption of fat (particularly saturated fats) plummeted. Fad, low-fat diet products became the norm at grocery stores as a high-carb, low-fat diet became the preferred method for weight loss. Yet, people kept gaining weight.
Clearly, something was not adding up.
Today, new studies show that fats are not the real culprit. A ketogenic diet dispels the fat makes you fat philosophy for several reasons. First, a diet high in carbs (especially refined and processed carbs from low-fat diet products) can increase insulin and blood sugar levels and promote inflammation in the body. In contrast, a low carb diet can help reduce inflammation far better than a low-fat diet.
Secondly, saturated fat is not shown to be harmful within the context of a low carb diet. It helps improve cholesterol levels, including increasing the amount of HDL (good) cholesterol while decreasing total triglyceride levels. These two factors help lower your risk of heart disease.
The Different Types of Ketogenic Diets
There are four main types of ketogenic diets. Each one takes a slightly different approach to fat vs. carb intake. When deciding which method works best for you, take into account your goals, fitness level and lifestyle.
The Standard Ketogenic Diet (SKD)
This is the most common and recommended version of the diet. Here, you stay within 20-50 grams of net carbs per day, focusing on moderate protein intake and high fat intake.
Targeted Ketogenic Diet (TKD)
If you are an active individual, this approach might work best for you. Targeted keto involves eating roughly 25-50 grams of net carbs or less 30 minutes to an hour before exercise.
Cyclical Ketogenic Diet (CKD)
If keto seems intimidating to you, this is an excellent method to start off with. Here, you cycle between periods of eating a low carb diet for several days, followed by a period of eating high carb (typically lasting several days).
High-Protein Ketogenic Diet
This approach is very similar to the standard (SKD) approach. The primary difference is the protein intake. While a standard keto diet will include moderate protein, here you up your protein intake considerably.
Note: The SKD method is the most used and researched version of keto. Therefore, the majority of information pertains to this standard method.