N‑Acetyl L‑Tyrosine (NALT)

Detailed overview

N-Acetyl-L-Tyrosine (NALT) is an acetylated, more water-soluble form of the amino acid L-tyrosine, marketed as a dopaminergic nootropic and mood-support supplement. Once the acetyl group is removed, tyrosine acts as the rate-limiting precursor for dopamine and norepinephrine synthesis via the tyrosine hydroxylase pathway, which is why users take it before cognitively demanding or high-stress tasks. However, human and animal parenteral-nutrition studies show that NALT is deacetylated inefficiently, with a large fraction of the dose excreted unchanged in the urine, so plain L-tyrosine usually raises plasma tyrosine more reliably. Any measurable cognitive benefit appears mainly under acute stressors such as sleep loss, cold or heavy mental workload, not in already rested people.