L-tyrosine / N-acetyl-L-tyrosine

Also known as tyrosine, NALT, n-acetyl tyrosine.

Last reviewed October 9, 2026 · Jump to references

What is L-tyrosine / N-acetyl-L-tyrosine?

In plain words

Tyrosine is an amino acid, a building block of protein, and NALT is a chemically modified form. The body uses tyrosine to make proteins, certain brain chemicals, thyroid hormones, and skin pigment. Researchers study tyrosine for maintaining attention and thinking during stress or sleep loss. Evidence for everyday mental benefits is limited, and NALT has not been shown to work better than regular tyrosine.

Technical definition

L-tyrosine is a proteinogenic amino acid synthesized from phenylalanine; N-acetyl-L-tyrosine (NALT) is its N-acetylated derivative. Rather than acting at one receptor, tyrosine serves as a substrate for protein synthesis and for pathways producing catecholamines, thyroid hormones, and melanin; NALT requires deacetylation to supply free tyrosine. Both are marketed as dietary supplement ingredients in the United States, where supplements are not FDA-approved for safety and effectiveness before sale.

Educational information only. This page does not provide medical advice or determine whether a supplement is appropriate for you. Review supplements with a qualified healthcare professional, especially if you take medication, are pregnant, have surgery scheduled, or have a chronic medical condition.

Evidence by use

Each use is rated on its own. There is no single overall effectiveness score.