Citrulline significantly increases muscle protein synthesis

A new study has shown that citrulline has a direct effect on muscle protein synthesis by redistributing ‘energy flows’ to its advantage. It is this property that makes it so beneficial for maintaining muscle mass in older people. Citrulline is converted in the body into arginine, an essential amino acid which plays a role in the health of blood vessels and which stimulates production of creatine, a nutrient associated with muscle development.

So would it not be easier to take arginine itself? Well, given the complexity of the human body, it’s not that simple. When arginine is ingested, it has to pass through the liver where it is almost totally broken down by an enzyme called arginase. Citrulline, on the other hand, successfully negotiates the liver to reach the kidneys where it is metabolised into arginine. It therefore represents an effective way of producing arginine and delivering its benefits for muscle protein synthesis.

To benefit from citrulline’s effects, you can increase your consumption of melon, watermelon, cucumber, chickpeas and dried fruits, or simply take a supplement containing an L-citrulline concentrate. Remember that between the ages of 20 and 60, research has shown we lose around 40% of our muscle mass.

---

Reference
A. Goron, S. Blanchet, É. Fontaine, C. Moinard. La citrulline réoriente les flux énergétiques au profit de la synthèse protéique musculaire, Nutrition Clinique et Métabolisme, Volume 31, Issue 3, Pages 242-243