When the body does not have enough glucose for energy, it turns to ketones, which it uses as a second source of energy. What is it about ? What are they really for?

Ketones are substances produced after glucose (“sugar”) is gone, and the body turns to alternative sources, including fat.

The body mobilizes its fat through beta-oxidation, which provides energy from oxidized fat.

The three substances observed come from the modification of fats in acetyl-coenzyme A by the liver. These ketones are subsequently eliminated in the urine:

• acetoacetate: formed from fatty acids, it converts to BHB or acetone;
• beta-hydroxybutyric acid (BHB): formed from acetoacetate;
• acetone: formed from acetoacetate and excreted in the urine.

BHB and acetoacetate are responsible for transporting energy from the liver to the limbs and organs.

On an empty stomach or following difficult physical exertion, the production of ketones is good. The production of ketones usually stops after a new meal if the body can either make enough insulin or receive the insulin by injection (if the person has diabetes).

The use of ketones is applied in all ketogenic type diets:

• to lose weight ;
• to manage blood pressure;
• to reduce appetite;
• to increase energy levels.

Ketones are a kind of compensatory energy released by the liver. Indeed, the main energy essential to the body comes from carbohydrates. When the carbohydrate level drops, the glucose level in the blood drops, and then it is the insulin’s turn to drop. This is how the body then finds another source of energy by converting lipids into ketone bodies.

Ketones are the “metabolism” of fat, lipids, by the liver.

Ketones are usually eliminated by the kidneys in the urine.

If the level is too low, hypoacetonemia is observed which is often associated with hypoglycemia.

If the ketone body level is too high: if the ketone bodies are not eliminated by the kidneys in the urine and produced in excess, they become toxic. This is called ketoacidosis, which is observed in particular in people with diabetes (in whom it is called “diabetic ketoacidosis” or sometimes “diabetic ketoacidosis”, when the amount of insulin in the blood is insufficient, especially before diagnosis of the disease.

Diabetic ketoacidosis is more common in people with type 1 diabetes and occurs when insulin levels are insufficient to meet the basic needs of the human body. Diabetic ketoacidosis is the first sign of type 1 diabetes in a minority of people.

It manifests itself with nausea, vomiting and abdominal pain. The conditions that have been examined can be serious and progress to coma.

Patients with diabetic ketoacidosis are hospitalized. The treatment consists of the administration of insulin, usually intravenously, to rebalance the level of sugar in the blood, physiological saline supplemented with glucose and potassium. Everything goes back to normal fairly quickly (between 8 and 12 hours) if the treatment does not start for too long afterwards.

Subsequently, the level of glucose in the blood as well as the absence of glucose and ketone bodies in the urine are frequently checked.

The prevention of diabetic ketoacidosis is based on daily monitoring of glycemic control to adapt the treatment, without forgetting insulin doses, on knowing how to add rapid subcutaneous insulin supplements to the usual treatment when There is ketonuria and finally without ever stopping the insulin so as not to risk coma ketoacidosis.

The most obvious sign of diabetic ketoacidosis is the very peculiar breath that is characterized by the smell of apples.

Ketonuria, which is the measurement of acetone in the urine, is usually undetectable in the urine if there is no pathology.

Blood tests indicate a decrease in blood pH, too high a blood glucose level (hyperglycemia), the existence of ketone bodies, as well as changes in potassium and sodium levels. In the blood, the normal level of acetone, ketosis, is generally less than <0.3 mmol / L.