You’ve heard of the keto diet. Everyone from Lebron James to the Kardashians has used the low-carbohydrate, high-fat diet for reasons like performance and weight loss.
The goal of the keto diet is to get the body producing ketones– a fundamentally different energy source than the carbohydrates and fats your cells typically use for energy. It can take several days of ketogenic eating before the body starts to produce ketones. And the time it takes to get into ketosis varies between individuals.
“Keto” comes from the word “ketogenic.” This is a nuanced term meaning that the body is producing ketones from fat.1 When blood ketone levels exceed 0.5mM, the body has achieved "ketosis." So ketosis can be achieved either through diet or fasting (meaning the body is producing its own ketones to be ketogenic), or also by consuming products that raise blood ketone levels (like HVMN Ketone or ketone salts or MCT oils).
Limiting carb intake and protein intake encourages the body to burn fat–and thus produce ketones. Importantly, restricting proteins as well as carbohydrates limits the amount of substrate available for gluconeogenesis. This is the process of making glucose from non-glucose molecules such as lactate, glycerol, or protein.
Because the ketogenic diet is low-carbohydrate, it often gets confused with other low-carb diets out there. Just because a diet is low carb doesn’t mean it’s keto. It’s subtle differences in the macronutrients provided in the diet determine if the diet is ‘ketogenic.’
A macronutrient is something humans consume in large quantities to provide the bulk of energy to the body. The primary macronutrients are carbohydrates, fats, and proteins. For a diet to be ketogenic, it must be high in fat, low-moderate in protein, and very low in carbohydrates.