Natural Factors L-Arginine is a non-essential amino acid involved in protein synthesis. It may also help support a modest improvement in exercise capacity in individuals with stable cardiovascular disease (CVD).

L-arginine is a conditionally essential amino acid, which means that although it can be manufactured by the body, the body may need more than it can produce on its own during times of illness, stress, and recovery from injury. L-arginine plays a critical role in the production of nitric oxide, a substance that relaxes blood vessels, helping to improve blood flow. A deficiency of L-arginine can disrupt many cellular functions in the body, including those of the blood vessels.

As a free-form amino acid, L-arginine is easier for the body to absorb and use than when consumed in the form of protein from food, such as dairy, meat, and fish. Available in two strengths, Natural Factors L-Arginine is pure, vegan, and free of preservatives, sweeteners, gluten, and GMOs. L-Arginine is a great choice for people who want to improve their exercise capacity, are under high levels of stress, or are involved in intense physical training.



May help support a modest improvement in exercise capacity in individuals with stable cardiovascular disease (CVD)
Supports protein synthesis
Helps replenish arginine levels during times of stress
Used to make nitric oxide, a compound in the body that helps relax blood vessels and improve blood flow