What is Ketosis 

Ketosis is a perfectly safe metabolic state where the body has shifted from using glucose as the primary fuel source to ketone bodies (ketones). Ketone bodies are made from fat in the liver.

This happens when the liver glycogen (sugar)  stores are used up. The liver stores between 100 and 150g of glycogen or about 2000 kcal of ‘sugar’ energy .

Both carbohydrates (starch and sugar) and fats can be used as fuel. The body will preferentially use carbohydrates because of its easy access and fast absorption, although burning fat is less inflammatory.

When switching to use fat as fuel, a period of adaptation needs to take place. This is called becoming ‘fat adapted’ or ‘keto adapted’ as the body has to break down fat, make ketone bodies and use the ketone bodies. The length of it takes to become fat adapted depends on how dependent a person previously was on glucose and how well their body accepts this new fuel source.

Ketosis occurs either over a prolonged period of fasting or by restricting carbohydrate intake significantly to 20g or less a day (about 5% of daily calories from carbohydrates). Ketosis means your body is using ketone bodies as fuel so there are different levels of ketosis. A mild state of ketosis can be obtained during exercise, sleep (body is in a fasted state) and calorie restriction.


Is Ketosis Safe?

It’s important to not confuse ketosis with medical ketoacidosis, like with untreated Type 1 diabetes which causes the pH levels in the blood to drop and become acidic.

Nutritional ketosis is perfectly safe and a great metabolic state to be in. This process is perfectly normal and is an adaptive response. During periods of famine, going into ketosis enabled humans  to survive and maintain vitality. Instead of relying on glucose for fuel we can to use our own body fat and thrive instead of starving to death.

Ketone bodies have the following properties;

Is it Unnatural To Be On a Ketogenic Diet?

The Inuit in Northern America have no available source of glucose in their habitat and their diet is consists of  mainly fatty fish and meat. The Masai tribe in Africa live on pasture lands and drink raw milk and eat the animals they farm. There is a very low occurrence of disease, obesity and cancer in these indigenous people and they live on ketogenic diet. Fat in of itself is actually a lot better for us, as long as it is not eaten at the same time as carbohydrates, due to something called the ‘Randle Cycle’.


The indigenous people with their unprocessed high animal product diets were perfectly healthy until hey came in contact with refined sugars/starches and processed seed oils from the West. After that cases of tooth decay, obesity, heart disease and diabetes sky rocketed.

In summary there are many benefits to being in ketosis and this is why there are some many benefits associated with fasting and a ketogenic or low carb diet.

Thank you for reading

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