Also known as: tyrosine, NALT, N-acetyl L-tyrosine
Latest evidence update: 2026-04-03
Strongest in Replication (79). Held back by Recency (40).
Solid mix of RCTs with some methodological gaps.
Confirmed across many independent studies with significant findings.
Tens of thousands of participants pooled across studies.
Mixed direction across studies.
Evidence base skews older; field may have moved on.
No per-outcome numbers yet for this one. Each finding's direction and strength is shown in the research below.
Areas where research points to a consistent direction of effect. The strength of evidence is graded; the size of the effect is not quantified.
Recommended: 500-2000mg
ProtocolEngine provides general health information based on published research. This is not medical advice. Consult a healthcare professional before starting any supplement or health protocol.
May improve cognitive performance under stress or demanding conditions, including faster information processing and better working memory
Does not improve physical endurance performance or exercise capacity in healthy individuals
Does not provide measurable benefits for growth, neuropsychological development, intelligence, or quality of life in people with phenylketonuria despite raising blood tyrosine levels
May improve mood and reduce depression in hospitalized patients with severe eating disorders
May enhance thermoregulatory responses to cold exposure in older adults