Dbetahydroxybutyrate

D-beta-hydroxybutyrate, often abbreviated as BHB, is one of the three main ketone bodies produced by the liver during periods of fasting, prolonged exercise, or carbohydrate restriction. The other two ketone bodies are acetoacetate and acetone. BHB is a water-soluble molecule that serves as an alternative fuel source for the body, particularly for the brain, which cannot directly utilize fatty acids for energy. When glucose levels are low, the liver converts fatty acids into BHB, which is then released into the bloodstream. Tissues that can utilize BHB can convert it back into acetyl-CoA, which then enters the citric acid cycle to produce ATP, the body's primary energy currency.

BHB is a chiral molecule, existing in two stereoisomeric forms: D-beta-hydroxybutyrate and L-beta-hydroxybutyrate. The D-isomer is the biologically active form and is the one predominantly produced and utilized by the body. The L-isomer is not readily metabolized and is therefore not considered an energy source. The presence of elevated BHB levels in the blood is indicative of ketosis, a metabolic state where the body primarily burns fat for fuel. This state can be achieved through ketogenic diets, intermittent fasting, or other forms of caloric restriction. Research into BHB is ongoing, with investigations into its potential roles in neuroprotection, metabolism regulation, and athletic performance.