Support metabolism and cardiovascular health:

Arginine, a known supporter of metabolism and cardiovascular health, has long been categorized as a “non-essential” amino acid because the body can make it. The caveat to that fact though is that production is limited, and arginine becomes “conditionally essential” as a limiting substrate under stress conditions [1]. One such stress condition is healing wounds after an accident or surgery. Nitric oxide (NO), which is produced from L-arginine by NO synthase in virtually all mammalian cells, plays a role in a myriad of cellular processes; one of which is wound healing. Arginine has been shown to promote wound strength and collagen deposition in the healing of acute wounds, likely supported by NO’s participation in the upregulation of cell signaling and protein synthesis [1].

How can L-Arginine support my health?

When it comes to cardiovascular function, L-Arginine is a vasodilator, meaning it relaxes blood vessels (making it a popular supplement among individuals seeking healthy erectile function). Supplementation has also been shown to benefit cholesterol balance [2,3], healthy blood flow [4], normal blood pressure [2], and the promotion of fat metabolism over fat synthesis [5,6]. In clinical studies, L-arginine supplementation has been associated with a reduction in endothelial dysfunction associated with high cholesterol and coronary heart disease, and acutely lowered blood pressure in normotensive and in salt-sensitive hypertensive individuals [2]. The endothelium is the inner lining of all blood vessels, and it’s where blood and the things it carries get stuck if the endothelium is not functioning properly. Oral supplementation of L-arginine in other clinical trials also demonstrated an effect of increased exercise-induced blood-flow, mediated by NO [4]. Reduced endothelial production of NO, specifically, is a key element in many of the processes associated with the development of atherosclerosis (hardening of the arteries) [3]. Therefore, L-arginine supplementation and its consequential upregulation of NO production is a means to support vascular health in a variety of ways.

Who should take L-Arginine?

L-Arginine also plays an important role in fat metabolism. Nitric oxide stimulates the oxidation of energy substrates (including fatty acids and glucose) throughout the body [5]. The tissues in which this process takes place include, but are not limited to, adipocytes (fat cells), the liver, skeletal muscle, and the heart [5]. Evidence shows that physiological levels of arginine and NO promote fat oxidation and decrease fat synthesis in a tissue-specific manner; suggesting arginine may regulate protein turnover, favoring muscle building over fat deposition [6]. Dietary arginine supplementation may also increase insulin sensitivity and amplify its signaling mechanisms on net protein synthesis [6].

Let us not forget to elaborate on L-arginine’s role in healthy erectile function. Penile erection requires relaxation of the cavernous smooth muscle, yet another action triggered by NO [7]. Clinical trials have shown that supplemental arginine, as a substrate for NO, has significantly benefited men who had previously experienced organic erectile dysfunction [7].


  1. Stechmiller, Joyce K., Beverly Childress, and Linda Cowan. “Arginine supplementation and wound healing.” Nutrition in Clinical Practice 20.1 (2005): 52-61.
  1. Siani, Alfonso, et al. “Blood pressure and metabolic changes during dietary L-arginine supplementation in humans.”American journal of hypertension 13.5 (2000): 547-551.
  1. Preli, Robert B., Karen Potvin Klein, and David M. Herrington. “Vascular effects of dietary L-arginine supplementation.”Atherosclerosis 162.1 (2002): 1-15.
  1. Hambrecht, Rainer, et al. “Correction of endothelial dysfunction in chronic heart failure: additional effects of exercise training and oral L-arginine supplementation.”Journal of the American College of Cardiology 35.3 (2000): 706-713.
  1. Fu, Wenjiang J., et al. “Dietary L-arginine supplementation reduces fat mass in Zucker diabetic fatty rats.” The Journal of Nutrition 135.4 (2005): 714-721.
  1. Jobgen, Wenjuan, et al. “Dietary L-arginine supplementation reduces white fat gain and enhances skeletal muscle and brown fat masses in diet-induced obese rats.” The Journal of nutrition (2008): jn-108.

Stanislavov, R., and V. Nikolova. “Treatment of erectile dysfunction with pycnogenol and L-arginine.” Journal of Sex & Marital Therapy 29.3 (2003): 207-213.