L-Methionine is an essential sulfur-containing amino acid required for protein synthesis, methyl group donation, and antioxidant defense. It plays a key role in detoxification, fat metabolism, and maintaining healthy skin, hair, and nails. As a USP-grade ingredient, L-Methionine is widely used in pharmaceuticals, nutraceuticals, and dietary supplements to support liver function, boost energy, and improve metabolic health.