Ornithine is a non-proteinogenic amino acid that plays a crucial role in the urea cycle, a process that helps remove ammonia from the body. It is produced in the liver and is essential for the conversion of ammonia into urea, which is then excreted in urine. Ornithine is not used to build proteins but is important for various metabolic functions. In addition to its role in detoxifying ammonia, ornithine is involved in the synthesis of other amino acids, such as arginine and citrulline. It is also studied for its potential benefits in promoting muscle growth and recovery, making it of interest to athletes and bodybuilders.