D-aspartic acid(DAA) is formed when the enzyme aspartate racemase converts L-aspartic acid into D-aspartic acid in the testes and other glands within the body. D-aspartic acid plays a vital role in the manufacturing of sperm cells and sex hormone production. Human studies have shown a significant increase in luteinizing hormone (LH), a messenger hormone that signals the testes to produce more testosterone, and a correlation to boosting testosterone levels in men when supplementing D-aspartic acid.
In one particular study, researchers gave a couple of dozen men aged between 27 and 37 a daily dose of 3.12 grams of D-aspartic acid for twelve days consecutively. Twenty other men were given a placebo. The testosterone level in the subjects that received the supplement had risen by 33% after the twelve days.
D-Aspartic acid