Some testosterone-boosting dietary supplements contain the amino acid D-aspartic acid. Some studies support that D-aspartic acid can increase testosterone production, but other studies refute this.

a short-lived molecular configuration where the reaction energy is maximum—L-amino acid had much more electrostatic stability than its D-type counterpart, due to the geometrical arrangement of ...

L-citrulline is also a non-essential amino acid, meaning that your body makes it on its own. However, it’s produced at levels lower than what you’d get by eating watermelon or via supplementation.

Like many other amino acids, it exists in two different forms: L-glutamine and D-glutamine. They are almost identical but have a slightly different molecular arrangement (2). The form found in ...

L-Lysine, or lysine, is an amino acid - which are organic compounds that link together to form proteins. Lysine is considered an essential amino acid because the body needs it but can't produce it.