What is ketosis?

Ketosis is a metabolic state. Think of being in or out of ketosis like the settings in a hybrid car; you can rely on gas or electricity to different degrees. In ketosis we rely on fat instead of carbs for energy and do so to such an extent that we start making ketones from fat.

These ketones can be used to fuel us and send many important signals to our cells. There are three different kinds of ketones: Acetoacetate (AcAc), β-Hydroxybutyrate (BhB) and Acetone.

AcAc is created first, and it can easily be converted into BhB. Technically, BhB isn’t a ketone. It’s close enough to one we still call it a ketone. Acetone is spontaneously created as a side product of AcAc. Acetone cannot be used as a source of energy but can be measured in the breath, serving as a useful but imperfect measurement of ketosis.

To know more about how to measure the depth of your ketosis check out our guide about how to measure ketone levels.

Your body is always producing a very low level of ketones, irrespective of your diet. You start producing more of them when following a diet that’s high in fat and low in carbs. For a weight stable person following a well-formulated ketogenic diet, that means about 5-10% of calories from carbs, 70-80% from fat and 20-30% from protein.

This excludes everything that is high in carbs, such as grains, potatoes, and sweets – or at the very least allows only tiny, infrequent portions of them. Low-carb vegetables such as kale, broccoli, salad, and other leafy greens can be eaten without restriction.

Nuts are also a keto friendly food given their high fat content. Macadamia nuts and pecans are very low in carbs and high in fat. Cashews on the other hand are relatively higher in carbs but still quite fatty.

Vegetables such as sweet peppers and tomatoes are ‘allowed’ but have a bit more carbs so may need to be moderated for those who are highly insulin resistant. The more insulin resistant you are, the harder is it to get into ketosis.

All meats, fish, eggs, birds and seafood are part of a well-formulated ketogenic diet. You’re encouraged to eat the fattier cuts and offal (e.g. liver). Liver is by far the most nutrient dense food.

While being in ketosis, you efficiently burn fat and use ketones as fuel. Ketosis is, therefore, a metabolic state that allows you to maximize fat burning. The amount of ketone production does however not correlate to fat loss, despite it facilitating fat loss for those who have extra fat to lose. Normalizing appetite is a big reason why.