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ING-030Ingredient Research Profile

Protein & Amino Acids

N-Acetyl L-Tyrosine (NALT)

Also known as: L-Tyrosine · NALT

●●○Moderate Evidence

A catecholamine precursor that replenishes dopamine and norepinephrine under stressful conditions, supporting cognitive performance when these neurotransmitters are depleted.

Effective Dose

500–2000mg / day

per clinical evidence

Evidence Level

Moderate

Protein & Amino Acids

Mechanism

Dopamine and norepinephrine precursor

primary action

Best For

Cognitive performance under stress

Focus, Mood

This profile is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications.

What Is N-Acetyl L-Tyrosine (NALT)?

Tyrosine is the precursor to dopamine, norepinephrine, and adrenaline. Its cognitive benefits are most pronounced under conditions that deplete catecholamines — physical stress, sleep deprivation, cold exposure, and high cognitive load. NALT (N-acetyl L-tyrosine) has greater water solubility but possibly lower bioavailability than free-form L-tyrosine.

How It Works: The Science

Tyrosine → DOPA (via tyrosine hydroxylase) → dopamine → norepinephrine → epinephrine. This rate-limited pathway depends on tyrosine availability. Under stress, catecholamine synthesis accelerates and tyrosine availability becomes limiting. Supplementation prevents the cognitive impairment associated with catecholamine depletion.

Primary Mechanism

Dopamine and norepinephrine precursor

Evidence-Based Benefits

Maintains cognitive performance during sleep deprivation

moderate

Neri et al. (1995) — 150mg/kg maintained psychomotor performance in sleep-deprived military personnel

Improves working memory under multitasking stress

moderate

Colzato et al. (2013) — 2g improved switching performance in a task-switching paradigm

Attenuates cold-stress cognitive impairment

moderate

Shurtleff et al. (1994) — 100mg/kg mitigated cold-exposure performance decline

Dosage Guide

Effective Dose

500–2000mg / day

500–2000mg free-form L-tyrosine or 300–1000mg NALT (higher water solubility but equivalent or lower effective dose). Best taken on an empty stomach, 30–60 minutes before the cognitively demanding task or training.

Safety Profile & Side Effects

Well tolerated at recommended doses. Avoid with MAO inhibitors (dangerous catecholamine accumulation). May worsen anxiety in susceptible individuals at high doses. Not recommended with thyroid medication (tyrosine is also a thyroid hormone precursor).

Who Should (and Shouldn't) Take It

Best for
Cognitive performance under stressFocusMood
Who it's for

Cognitive athletes, shift workers, students, and anyone performing under sleep deprivation or significant stress. Does not reliably improve performance in well-rested, stress-free conditions.

Frequently Asked Questions

What is the recommended dose of N-Acetyl L-Tyrosine (NALT)?

500–2000mg free-form L-tyrosine or 300–1000mg NALT (higher water solubility but equivalent or lower effective dose). Best taken on an empty stomach, 30–60 minutes before the cognitively demanding task or training.

Is N-Acetyl L-Tyrosine (NALT) safe?

Well tolerated at recommended doses. Avoid with MAO inhibitors (dangerous catecholamine accumulation). May worsen anxiety in susceptible individuals at high doses. Not recommended with thyroid medication (tyrosine is also a thyroid hormone precursor).

How does N-Acetyl L-Tyrosine (NALT) work?

Tyrosine → DOPA (via tyrosine hydroxylase) → dopamine → norepinephrine → epinephrine. This rate-limited pathway depends on tyrosine availability. Under stress, catecholamine synthesis accelerates and tyrosine availability becomes limiting. Supplementation prevents the cognitive impairment associated with catecholamine depletion.

Who should take N-Acetyl L-Tyrosine (NALT)?

Cognitive athletes, shift workers, students, and anyone performing under sleep deprivation or significant stress. Does not reliably improve performance in well-rested, stress-free conditions.

Related Ingredients

CaffeineL-TheanineAlpha-GPC

Medical Disclaimer

Ingredient profiles are for informational purposes only and do not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications. Full disclaimer →