What are ketone bodies and how they are synthesized in the body?

Acetoacetate, Beta-hydroxybutyrate (BHB) and acetone are collectively known as ketone body. These are normal metabolites sythesised by the liver from fat or protein when glucose is not available as a energy source. These are exported into the systemic circulation to serve as a energy source for most of the extrahepatic tissues. These are short-chain organic acids that can freely move across cell membranes, even the blood brain barrier (BBB). These are high-octane fuel for the body and can provide 60% -70% 2 of ATP. Oral Consumption of D-β-HB ester provides 30% more energy 3 compared to glucose intake.

What are the normal levels of KB in our body?

Serum levels of ketones are normally <0.5 mmol/L. Hyperketonaemia 4 occurs at level of ketones >1mmol/L.

Serum levels of ketones
What is Ketosis?

Ketosis is the end result of a shift in the insulin/glucagon ratio and indicates an overall shift from a glucose based metabolism to fat based metabolism providing ketone bodies.

Source of Ketone bodies

The source of ketone bodies can be endogenous or exogenous.

Endogenous: It is produced within the body to give energy in alarming conditions like during

Short term fasting fatty acids are the source for ketone bodies

Long term fasting aminoacids are the source for ketone bodies

Exogenous β-HB can be derived naturally or synthetically. In nature, it is present in small amounts, in many foods of animal origin like eggs and milk; of plant origin eg. Passiflora micrantha. Synthetically, it can be produced as a precursor to the ketone body, (3R) hydroxybutyrate by one enamtiomer of Organic Carboxylic Acyclic Acids; like (R)-3- hydroxy butyl (R)-3-5 hydroxy butyrate. What is a ketogenic diet (KD) ? The ketogenic diet is a high-fat, adequate-protein, low-carbohydrate diet. The diet forces the body to burn fats rather than carbohydrates. If there is very little carbohydrate in the diet, the liver converts fat into fatty acids and ketone bodies.

Fate of Ketotek
Fate of Ketotek or Exogenous ketone bodies

The Ketone diet or Ketone ester ultimately provides the ketone bodies to the circulation which, finally acts and releases the ATP for the damaged cells.This supplement works exactly same way how the ketogenic diet works. In case of ketogenic diet, you consume high fat, moderate protein and very low carbs bringing your body into a state of ketosis.

Ketone esters are cleaved in the gut and are absorbed and transported through the gut epithelium and monocarboxylate transporters (MCT) as ketone bodies into the circulation. Now, your body burns these ketones as fuel instead of relying on glucose It is metabolised by extrahepatic tissues like muscle, brain heart etc and converts to acetoacetate. Acetoacetate, is activated to Acetoacetyl CoA Then, it enters the tricarboxylic acid (TCA) cycle as acetyl-CoA for energy.