L-citrulline is a non-essential amino acid that plays a crucial role in the urea cycle, which is the process by which the body eliminates toxic byproducts of protein metabolism, primarily ammonia. It’s found naturally in foods like watermelon, but it can also be produced synthetically.

L-citrulline is often used as a dietary supplement due to its potential health benefits. It is commonly taken to improve exercise performance, increase blood flow, and alleviate symptoms of certain medical conditions, such as erectile dysfunction and high blood pressure.

One of the reasons L-citrulline is favored over its precursor, L-arginine, in supplementation is because it is more efficiently absorbed by the body and thus may lead to higher levels of arginine in the blood. Arginine, in turn, is a precursor to nitric oxide, a molecule that helps dilate blood vessels, leading to improved blood flow. This is why L-citrulline is often used by athletes and those seeking to enhance cardiovascular health or exercise performance.

Taking L-citrulline can offer several potential benefits:

1. Improved exercise performance: L-citrulline supplementation has been shown to increase exercise performance by enhancing blood flow and reducing fatigue. It may also help improve endurance and reduce muscle soreness after exercise.*
2. Increased nitric oxide production: L-citrulline is converted into L-arginine in the body, which is then converted into nitric oxide. Nitric oxide is a molecule that helps dilate blood vessels, leading to improved blood flow.*
3. Enhanced recovery: L-citrulline supplementation may help speed up recovery after exercise by promoting muscle protein synthesis and reducing muscle soreness.*

While L-citrulline is generally considered safe for most people when taken at appropriate doses, there are some potential considerations to keep in mind:

1. Gastrointestinal issues: Some individuals may experience gastrointestinal discomfort, such as bloating, diarrhea, or stomach cramps, when taking L-citrulline supplements. These side effects are usually mild and can often be minimized by taking L-citrulline with plenty of water and/or with meals.
2. Hypotension (low blood pressure): Since L-citrulline supplementation can increase nitric oxide production and promote vasodilation (widening of blood vessels), it may cause a decrease in blood pressure, especially in individuals who are already prone to low blood pressure or taking blood pressure medication.
3. Individual variability: Not everyone responds to L-citrulline supplementation in the same way. While many individuals experience benefits, some may not see significant improvements.