L-Norvaline
An analog of the BCAA valine that may indirectly boost nitric oxide by inhibiting the arginase enzyme.
Also known as: Norvaline
Overview
L-Norvaline is a form of the branched-chain amino acid (BCAA) valine. Its primary mechanism of action in supplements is the inhibition of the enzyme arginase. Arginase is responsible for breaking down arginine, the precursor to nitric oxide (NO). By inhibiting arginase, L-Norvaline is proposed to increase the amount of available arginine, leading to greater and more sustained nitric oxide production, which enhances blood flow and muscle pumps.
Key Benefits
Inhibits Arginase
The primary proposed benefit is its ability to block the arginase enzyme, which degrades arginine.
Potentiates Nitric Oxide Production
By preserving the body's pool of arginine, it may lead to more significant and longer-lasting increases in nitric oxide when combined with an NO precursor like citrulline or arginine.
Improves Blood Flow
Enhanced NO levels lead to vasodilation (widening of blood vessels), which can improve blood flow, nutrient delivery, and muscle pumps during a workout.
Dosage & How to Take
There is no clinically established dose, but it is commonly included in pre-workouts at 100-200 mg.
| Purpose | Dose | Notes |
|---|---|---|
| Pre-Workout Pump | 100-200 mg | Typically stacked with L-Citrulline or other nitric oxide boosters 30-45 minutes before training. |
Best Time to Take
Best taken pre-workout to coincide with the intended increase in blood flow during exercise.
With or Without Food
Should be taken on an empty stomach for best absorption.
Forms & Bioavailability
| Form | Absorption | Best For | Notes |
|---|---|---|---|
| L-Norvaline Powder | Moderate | Inclusion in pre-workout formulas. | Effectiveness and safety are still subjects of scientific debate. |
Side Effects & Safety
Common
- Anecdotally well-tolerated at common doses.
Rare
- Concerns have been raised by in-vitro (test tube) research suggesting potential neurotoxicity and cell death at high concentrations. The relevance to human supplementation at standard doses is currently unknown and debated.
Contraindications
- Due to safety concerns from preliminary research, it should be avoided by pregnant/breastfeeding women and those with pre-existing medical conditions until more research is available.
Interactions
Scientific Research
The arginase inhibitor L-norvaline is neuroprotective in a model of focal cerebral ischemia
In an animal model of stroke, L-norvaline showed neuroprotective effects, suggesting a complex role for arginase inhibition in the brain. This is not a sports performance study.
The dietary supplement L-Norvaline is cytotoxic to human brain microvascular endothelial cells in vitro
An in-vitro study found that L-Norvaline was toxic to brain cells at certain concentrations, raising safety questions that require further investigation.
Food Sources
Frequently Asked Questions
Medical Disclaimer
This content is for educational and informational purposes only and is not intended as medical advice. Always consult with a qualified healthcare professional before starting any supplement regimen, especially if you have pre-existing health conditions or are taking medications. The statements on this page have not been evaluated by the Food and Drug Administration.