β-Alanine is a non-essential amino acid and the only naturally occurring beta amino acid. It is a rate-limiting precursor of carnosine, which acts as an intracellular proton buffer in skeletal muscles. β-Alanine supplementation can increase muscle carnosine concentration, delay fatigue during high-intensity exercise, and enhance muscle work capacity. It is formed through the degradation of dihydrouracil and carnosine, and is mainly obtained from animal-based foods.