Doctor?s Best L-Arginine supplies an amino acid vital in the synthesis of nitric oxide which is an essential compound that helps blood circulation. Arginine-derived nitric oxide benefits wound healing and overall circulation and has been shown to help increase mental acuity immune function and memory.* Research suggests that L-Arginine supplementation helps increase muscle mass and may also positively be beneficial in improving endurance as it is a precursor to creatine which helps supply energy to all cells of the body.* At Doctor?s Best we lead with science. Our products are backed by research and crafted using pure ingredients carefully sourced from around the globe. Since 1990 we have dedicated ourselves to providing highly effective nutritional supplements that enable you to live a healthier lifestyle. We want nothing more than to see you and your family thrive!