Ingredient
L-Leucine
What is L-Leucine?
L-Leucine is an essential amino acid, meaning the body cannot produce it, and it must be obtained through diet. It is found in foods like meat, dairy products, and legumes, and is often synthesized for use in supplements.
It is primarily used in protein powders and supplements to support muscle growth and repair, as it plays a crucial role in protein synthesis. Some fitness enthusiasts believe that L-Leucine aids in muscle recovery, although the scientific evidence varies, with some studies supporting its benefits in resistance training contexts and others showing limited effects.
When you see L-Leucine on a label, it's usually included for its potential to help maintain muscle mass, particularly in athletes and those engaged in intensive physical activity.
Commonly found in: Protein Powders, Dietary Supplements, Sports Nutrition Products
Benefits
- L-Leucine supports muscle protein synthesis, helping with muscle growth and repair.
L-Leucine is generally recognized as safe (GRAS) when used as a food additive and supplement.
While evidence supports its role in muscle protein synthesis, the effectiveness of supplementation for muscle growth in all contexts is still debated.
L-Leucine can be derived from both animal and plant sources, so its vegan status depends on the source material used in a particular product.
Sources: Amino Acids Overview
Scout's take
Part of BCAAs. Free-form branched-chain amino acids supporting muscle protein synthesis and recovery.
More from Scout's analyses
Part of Added BCAAs. Free-form branched-chain amino acids supplementing the plant protein blend; helps offset the lower per-serving leucine content of plant proteins.
from the analysis of PlantFusion Complete Protein Creamy Vanilla BeanKey branched-chain amino acid that directly stimulates muscle protein synthesis; targeted addition for recovery.
from the analysis of Noble All-in-One ProteinFound in 4 products
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