What is arginine?

Arginine is a conditionally essential amino acid. Your body can produce it under normal circumstances, but this may not always meet your needs. Demand can increase during periods of growth, stress, illness or increased physical activity.

You can find arginine naturally in many protein rich foods. Your body can also produce arginine from citrulline, mainly in your kidneys. Arginine supports several important metabolic processes. Its most well studied role is producing nitric oxide, a signalling molecule that supports healthy cardiovascular and immune function.

Nitric oxide and cardiovascular health

Your body produces nitric oxide (NO) from arginine using enzymes called nitric oxide synthases. Nitric oxide plays an important role in keeping your blood vessels healthy and flexible.

It helps relax the smooth muscle in your blood vessel walls. This process, known as vasodilation, supports healthy blood pressure and efficient blood flow. It also helps maintain the health of your endothelium, the delicate inner lining of your blood vessels.

Arginine also supports healthy platelet function and helps maintain normal platelet aggregation. This contributes to healthy circulation and supports normal blood flow.

Getting enough arginine can therefore support nitric oxide production and healthy circulation.

Immune function and wound healing

Arginine provides important support for your immune system. It helps fuel immune cells such as macrophages and T lymphocytes. It also supports nitric oxide production and the formation of proteins needed for a normal immune response.

Arginine is also needed to produce collagen and polyamines. These compounds support cell growth and tissue repair. This makes arginine useful for supporting your body’s natural recovery processes after physical activity.

If you lead an active or physically demanding lifestyle, arginine can provide both circulatory and recovery support.

Supplementing with arginine

Arginine supplements are available in several forms, including L arginine hydrochloride and L arginine alpha ketoglutarate (AAKG). Your body does not absorb all supplemental arginine efficiently. A significant amount can be broken down in your gut before reaching your bloodstream.

For this reason, some supplements combine arginine with citrulline. Your kidneys convert citrulline into arginine, helping to raise blood arginine levels efficiently. Take arginine supplements on an empty stomach to support absorption. When used as directed, arginine is generally well tolerated.