Ingredients

L-theanine

Theanine

L-theanine is a non‑proteinogenic amino acid, chemically described as N(5)-ethyl‑L‑glutamine, occurring naturally mainly in tea leaves (Camellia sinensis) and in some mushrooms. In supplements it is typically used as purified L‑theanine in powder or capsule form, obtained either from tea extraction or via fermentation/biotechnological production. On labels it may also appear simply as “theanine”, with the L‑form being the most commonly used in finished products. As a water‑soluble ingredient, it blends well into drink mixes, stick packs and soluble powders. In cosmetics it is less common but may be included as a conditioning component in water‑based formulas, generally at low concentrations and alongside humectants and other amino acids.