From the Guidelines
L-citrulline is beneficial for improving blood flow and exercise performance, particularly in patients with pulmonary arterial hypertension (PAH), as it enhances nitric oxide production and vasodilation 1. The primary mechanism of L-citrulline is its conversion to L-arginine in the body, which then produces nitric oxide, a compound that relaxes blood vessels and improves circulation.
- Key benefits of L-citrulline include:
- Improved hemodynamics in patients with PAH, as evidenced by decreased mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR) 1
- Enhanced exercise capacity, as demonstrated by increased peak oxygen uptake and decreased ventilatory response to carbon dioxide production 1
- Potential benefits for cardiovascular health, including lowered blood pressure and improved symptoms of erectile dysfunction
- Typical dosages of L-citrulline are not explicitly stated in the provided evidence, but oral supplementation of L-arginine, which is converted to L-citrulline in the body, has been studied at doses of 0.5 g/10 kg body weight or 1.5 g/10 kg body weight per day 1
- It is essential to note that while L-citrulline may have potential benefits, further clinical studies are needed to fully understand its effects, particularly in the context of long-term oral supplementation 1
From the Research
Benefits of L-Citrulline
- L-citrulline is a natural precursor of L-arginine, which is a substrate for nitric oxide synthase (NOS) in the production of nitric oxide (NO) 2
- Supplemental administration of L-citrulline has been shown to improve NO production and cardiovascular function in cardiovascular diseases associated with endothelial dysfunction, such as hypertension, heart failure, atherosclerosis, diabetic vascular disease, and ischemia-reperfusion injury 2
- L-citrulline may be beneficial for men with mild erectile dysfunction, as it has been shown to improve erection hardness and increase the number of intercourses per month 3
- Combination therapy of L-citrulline and transresveratrol may be effective for erectile dysfunction treatment in men with added on-demand use of phosphodiesterase 5 inhibitors 4
Exercise Performance
- Citrulline malate supplementation has been investigated as an ergogenic aid for resistance exercise performance, but its effects on blood flow, metabolic efficiency, and performance during maximal isokinetic leg extension exercise are limited 5
- Beetroot juice supplementation has been shown to increase nitrate/nitrite levels, but neither citrulline malate nor beetroot juice supplementation was found to enhance performance, blood flow, metabolic efficiency, or the hormonal response to leg extension exercise 5