L-Leucine
The short version
An essential branched-chain amino acid — used as a tabletting lubricant and a sweetness modifier.
It's widely considered safe at the amounts used in food, so we mark it green. The Safety section below has the details.
Where it comes from
Produced industrially by bacterial fermentation. An essential amino acid present in all dietary proteins.
How it's used
Most familiar as a sports supplement (anabolic signal). As a food additive in the EU, it functions primarily as a tabletting lubricant and flow agent in tabletop sweetener and supplement tablets — replacing magnesium stearate where a more 'natural' label is preferred. Some flavor-modifying use at low doses.
Safety profile
ADI not specified — endogenous nutrient. Dietary additions metabolized identically to protein-derived leucine. Pharmacological supplement doses are sometimes restricted in clinical maple-syrup-urine-disease patients (a rare inborn error of metabolism).
Physical & chemical properties
White crystalline powder, sparingly soluble in cold water. Heat-stable. Slightly bitter taste in concentration.
Regulation worldwide
Permitted in the EU as a food additive (with specific use restrictions for tablets and supplements) and globally as a nutritional ingredient.
Educational information only. Not medical or dietary advice.