Betaine is a naturally occurring compound found in various foods, such as beets, spinach, and whole grains. It is classified as an amino acid derivative and plays a role in several biological processes, including the metabolism of homocysteine, an amino acid linked to heart health. In addition to its dietary sources, betaine is often used as a dietary supplement. It is believed to support athletic performance, improve muscle mass, and enhance liver function. Research is ongoing to fully understand its benefits and potential applications in health and wellness.