Is Leucine vegan?

Leucine

Vegan

Leucine is an essential branched-chain amino acid used in cosmetics as a skin-conditioning agent and in food as a flavour enhancer. It is commonly produced via fermentation or extraction from plant proteins.

Also known as (S)-Leucine, 2-Amino-4-methylpentanoic acid, Alpha-aminoisocaproic acid, L-Leucine
INCI name Leucine
E number E641
CosIng ID 35003
Last reviewed 22 April 2026

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