Ketones are organic water soluble compounds, chemically characterised by the presence of carbonyl group in which a carbon atom forms a double bond with an oxygen atom and joins with two other carbons. Increased ketone level (B-hydroxybutyrate) in the blood called ketosis which is nutritional as long as ketone level in the blood is within the normal average which is 0.3-5mmol/l.
They are the three ketones released in the liver as by-products during the process of fat metabolism. It includes beta- hydroxyl butyrate, acetoacetate and acetone. The last one is excreted in the urine while the other two are used for energy.
The body usually depends on glucose for energy .In cases of fasting, and starvation there is a decrease in blood glucose levels. That pushes the body to utilize the stored fat and release fatty acids and ketones as an alternative source of energy. This ketone production is mainly for the brain.
All the body organs can either use glucose or fatty acid as a source of energy except the brain. The brain can only use glucose or ketones to produce the energy it needs .Ketones are the preferable source of energy for the brain as the fatty acids are the preferable source of energy for the heart.
Due to the myths of our time, we are encouraged to follow a low- fat diet to keep our heart and brain healthy, but in truth our heart and brain prefer fat sources to function better and become healthier.