β-hydroxybutyrate

β-Hydroxybutyrate (BHB) is a type of molecule called a ketone body produced when the body burns fat for energy instead of carbohydrates, especially during fasting or a low-carb diet. It serves as an alternative fuel source for the brain, muscles, and other tissues when glucose is scarce. BHB is also used as a supplement to support energy, mental clarity, and metabolic health. It plays a key role in the body's adaptation to fasting or ketogenic states, helping maintain energy levels and reducing reliance on sugar-derived fuel.