Fasting leads to a state of ketosis and fat-adaptation. Because of that, many people practicing fasting experience its benefits such as more energy and focus, healthy blood sugar level, weight loss, improved blood pressure and heart health. Let’s dive in and look at what ketosis and fat-adaptation is, and what we need to do to reap its benefits.

What is ketosis

Ketosis is a metabolic state in which fats, in the form of ketone bodies, become the main  source of energy for the body and brain. Ketosis develops when carb intake is very low, roughly 20-50 grams of net carbs per day, or during periods of fasting.

Ketogenesis is the metabolic pathway that produces ketone bodies. The body is constantly producing small amounts of ketone bodies. However,  when ketone bodies reach a certain threshold the body enters in a state of nutritional ketosis. According to researchers, nutritional ketosis is defined as blood ketone levels of 0.5 to 3 mg/dL.

Ketosis  is often inefficient and unstable in the early phases. A sudden increase in carb intake can quickly make the body shift back to using carbs as a main source of energy.  Staying into ketosis long term and truly enjoying the health benefits of this metabolic state is achieved though fat adaptation.

Fat adaptation

Most people are “carb adapted” because they consume moderate or  high amounts of carbs in the diet.  Their bodies use mostly carbs as the main source of energy, although they can burn limited amounts of  fats, too.

Those who follow a ketogenic diet or practice fasting initially enter into a state of ketosis, when fats are used as the main source of energy. As this state of ketosis is maintained over several weeks, they become “fat-adapted.”

Fat adaptation occurs later than ketosis, but is a long-term, stable metabolic state in which the body uses ketone bodies as the main  source of energy.

Fat adaptation is beneficial for everyone because the body becomes highly effective at using fat for energy, and can easily burn fat when needed.

Fat adaptation is also great for those who practice intermittent fasting or keto diet on and off (means keto cycling, which has short periods of eating more carbs and falling out of ketosis). Being fat adapted means that the body is metabolic flexible and can  easily return to burning fat once the fasting days or keto diet is restarted.

Signs suggesting that your body has become fat adaptation include: reduced cravings, more energy, increased mental focus, reduced body fat and increased athletic performance.

Factors that affect ketosis and fat adaptation

The fastest way to achieve ketosis is  fasting  because there are no foods consumed that could be converted into glucose. Keto diet also leads to a state of ketosis but the process seems to be slower.

Combining fasting or keto diet with high intensity workouts helps a person enter ketosis faster. However, it is more beneficial to stay in ketosis for the long term, and have your body become fat-adapted. The time required to become fat-adapted may vary based  on the initial weight and metabolic factors.

Getting into ketosis does not guarantee fat adaptation.  It takes time, and you need to be consistent with your dietary habits and lifestyle. To speed up the process of being fat adapted, consider fasting, eating less carbs and more fat, and exercise regularly.