L-Glutamic acid, a non-essential amino acid, holds a critical position in numerous biological processes within the human body. As a key neurotransmitter in the central nervous system, glutamic acid facilitates excitatory neurotransmission, playing a fundamental role in synaptic signaling, learning, and memory formation. Beyond its neurotransmitter function, L-glutamic acid serves as a precursor for the synthesis of the antioxidant glutathione, which protects cells from oxidative damage and supports detoxification pathways. Moreover, glutamic acid contributes to the metabolism of other amino acids, including proline, arginine, and ornithine, and is involved in the urea cycle, aiding in the removal of excess nitrogen waste. Widely distributed in protein-rich foods such as meat, poultry, fish, dairy products, and plant sources, L-glutamic acid is essential for human nutrition and overall health. Its multifaceted roles underscore its significance in maintaining neurological function, cellular integrity, and metabolic homeostasis.