L-Leucine is most commonly used in formulation of protein powders that are intended to be consumed by athletes & bodybuilders. It is an essential amino acid which is known to play a key role in synthesis of proteins. This is a branched chain amino acid that has chemical formula C6H13NO2 with molar mass of 131.18 g/mol. With E number E641, it is extensively utilized as flavor enhancer in food industry. L-Leucine has ability to slow down muscle degradation and is metabolized in liver and adipose & muscle tissues.