Used as a dietary supplement to support muscle recovery and growth, particularly in athletes and bodybuilders. It aids in protein synthesis and helps maintain nitrogen balance in the body. Often included in sports nutrition products like protein powders and amino acid blends. Also utilized in medical nutrition for patients recovering from surgery or illness to promote tissue repair and immune function.

In the pharmaceutical industry, it serves as a component in certain medications related to muscle and nervous system disorders. In the food industry, it acts as a flavor enhancer and nutrient additive in various products.

Additionally, it is used in the cosmetics industry to nourish skin and hair by stimulating collagen and keratin production. In agriculture, DL-Leucine is incorporated into animal feed to enhance growth, nutrient absorption, and muscle development in livestock.

Furthermore, it is employed in research and development for studying metabolic pathways, amino acid functions, biochemical processes, and developing new biotechnology products related to health and well-being.