L-citrulline

Table of Contents

Other names

L-Citrulline Malate
Free-Form L-Citrulline
Watermelon-Derived Citrulline

Synopsis

L-Citrulline is a non-essential amino acid that plays a crucial role in nitric oxide production, which helps improve blood flow and vascular health. It is synthesized in the body from L-arginine and ornithine and is primarily found in watermelon, though it is also available in supplement form. L-citrulline is converted into L-arginine in the kidneys, which in turn helps increase the levels of nitric oxide (NO), a molecule that helps dilate blood vessels and improves vascular relaxation.

Because of its role in nitric oxide production, L-citrulline is widely used in sports nutrition to enhance exercise performance, improve endurance, and reduce muscle soreness post-workout. It helps improve the delivery of oxygen and nutrients to muscles, reducing fatigue and promoting faster recovery. L-citrulline has also been studied for its potential to lower blood pressure, support heart health, and boost immune function.

In addition to exercise-related benefits, L-citrulline is used in medical settings to help treat conditions related to vascular health, such as erectile dysfunction, heart failure, and high blood pressure.

Historical Use
L-citrulline was first identified in 1930 by scientists who isolated it from watermelon. Its name comes from the Latin word for watermelon, Citrullus, due to the high concentration of the amino acid found in this fruit. While not traditionally used in herbal medicine, the discovery of its beneficial effects on vascular health and blood flow led to increased research into its therapeutic potential, particularly in modern sports science and cardiology.

Its potential to enhance blood flow and nitric oxide levels became well-known in the early 2000s when it started being included in pre-workout and endurance supplements, specifically for athletes looking to optimize exercise performance and muscle recovery.

Modern Use
L-citrulline is commonly used in sports nutrition and fitness supplements, especially in formulas designed for improving exercise endurance, muscle recovery, and blood flow. Its most common uses include:

  • Enhancing athletic performance: By increasing nitric oxide production, L-citrulline helps improve oxygen delivery, reduce muscle fatigue, and increase exercise endurance. It is often included in pre-workout and post-workout formulas.
  • Reducing muscle soreness: L-citrulline has been shown to decrease delayed onset muscle soreness (DOMS), helping athletes recover more quickly after intense physical activity.
  • Supporting cardiovascular health: L-citrulline’s ability to improve blood flow and lower blood pressure makes it beneficial for heart health, and it is sometimes used in the management of hypertension and erectile dysfunction.
  • Improving endurance and energy: It may improve exercise capacity in those with chronic fatigue or vascular conditions.

L-citrulline is typically taken in powdered, capsule, or tablet form, often in doses ranging from 3 to 6 grams per day for exercise performance and muscle recovery. It is often paired with other ingredients like L-arginine, beta-alanine, and creatine in sports supplements.

Safety Considerations
L-citrulline is generally considered safe when used at recommended dosages. However, excessive intake may cause gastrointestinal discomfort, such as bloating or diarrhea. It is important to consult with a healthcare provider before beginning supplementation, particularly for individuals with low blood pressure, heart conditions, or those taking medications that affect vascular function.

Uses: Health Conditions

Athletic and Exercise Aids (Traditional)
Endurance (lack of) (Traditional)
Erectile Dysfunction (Traditional)
Exercise (Traditional)

Body Systems

Muscles (Science)
Circulatory System (Science)
Male Reproductive System (Science)
Mitochondria (Science)