L-Tyrosine (NALT)
Military and stress trials found tyrosine reduced performance decline during one night of sleep loss (Neri et al., 1995, 150mg/kg), noise stress (Deijen & Orlebeke, 1994, 100mg/kg) and a combat training course (Deijen et al., 1999, 2g/day) — but neither Deijen trial found any effect on mood. Other trials were null or negative: tyrosine did not protect cognition or performance under exercise heat stress (Coull 2016, 150mg/kg), and 2g worsened cognitive flexibility under high cognitive load (Robson 2019). A 2015 narrative review (Jongkees et al.) concluded benefits are conditional on short-term stress that depletes dopamine and norepinephrine.
Evidencia revisada el
Mecanismo de acción
L-Tyrosine is an amino acid precursor to dopamine, norepinephrine, and epinephrine. Under conditions of stress, sleep deprivation, or cognitive load, the brain depletes catecholamine stores. Supplementing tyrosine replenishes the substrate for neurotransmitter synthesis, maintaining cognitive performance when it would otherwise decline.
Resumen de evidencia clínica
Military and stress trials found tyrosine reduced performance decline during one night of sleep loss (Neri et al., 1995, 150mg/kg), noise stress (Deijen & Orlebeke, 1994, 100mg/kg) and a combat training course (Deijen et al., 1999, 2g/day) — but neither Deijen trial found any effect on mood. Other trials were null or negative: tyrosine did not protect cognition or performance under exercise heat stress (Coull 2016, 150mg/kg), and 2g worsened cognitive flexibility under high cognitive load (Robson 2019). A 2015 narrative review (Jongkees et al.) concluded benefits are conditional on short-term stress that depletes dopamine and norepinephrine.
Matriz de efectos en humanos
Basado solo en ensayos clínicos en humanos. Se excluyen los datos en animales e in vitro.
| Efecto | Evidencia | Magnitud | Estudios |
|---|---|---|---|
| Cognitive Performance Under Stress | mixta | Moderado | 6 |
| Mood Under Stress | mixta | Insignificante | 2 |
Clave de evidencia: Sólida = varios ECA consistentes · Moderada = ECA más pequeños o menos numerosos · Preliminar = ensayos iniciales o n pequeño · Mixta = resultados contradictorios
Beneficios documentados
- Cognitive performance under some acute stressors (sleep loss, noise, combat training)
- Focus in demanding conditions
Efectos secundarios y precauciones
- Generally safe
- May worsen cognitive flexibility under high cognitive load (one RCT at 2g)
- MAO inhibitors: theoretical interaction (tyrosine is a catecholamine precursor), no clinical reports found — ask your doctor before combining
- Possible hyperthyroid effects at very high doses
- May interact with thyroid medications
Cómo tomarlo
Recomendaciones de combinación
Ingredientes que se combinan bien con L-Tyrosine (NALT) y por qué.
L-Tyrosine supplies dopamine/norepinephrine substrate for focus and drive; L-Theanine keeps you calm and prevents the cortisol spike from stress or caffeine. Together they produce focused, calm high-performance state under demanding conditions.
Rhodiola modulates monoamine availability and HPA axis; Tyrosine replenishes the substrate for those monoamines. Both work best under stress conditions — they target the same problem (cognitive decline under stress) via complementary mechanisms.
Often paired with caffeine; we cite no trial of L-Tyrosine with caffeine.
Preguntas frecuentes
Does L-Tyrosine work if I am not stressed or sleep-deprived?
Probably not meaningfully. This is the key nuance of tyrosine. The evidence shows it prevents cognitive decline under stress — it restores depleted catecholamines. In a rested, non-stressed baseline state, catecholamine levels are already sufficient, so adding precursor does not produce a noticeable effect. Think of it as an insurance policy for demanding days, not a daily cognitive enhancer.
L-Tyrosine vs NALT — which form should I buy?
Plain L-Tyrosine. The stress trials with positive results used plain L-Tyrosine — at 2g/day or at weight-based doses of 100–150mg/kg — taken about an hour before the demand. NALT is commonly used in formulated stacks (easier to cap), but no trial comparing it with plain L-Tyrosine for cognition was found.
Does it interact with thyroid medications?
Yes — L-Tyrosine is a precursor to thyroid hormones (T3 and T4). At standard doses, this is not clinically significant for most people. However, if you have hyperthyroidism or are on levothyroxine or other thyroid medications, supplemental tyrosine could theoretically affect hormone levels. Consult your doctor before use if you have any thyroid condition.
Can L-Tyrosine help with ADHD?
It is not established. Tyrosine is a dopamine precursor, but our 2026 evidence review did not assess ADHD trials, and a 2015 review judged its potential for treating clinical disorders minimal. L-Tyrosine is not a substitute for ADHD treatment — talk to your doctor before combining it with any medication.
Principales stacks que contienen L-Tyrosine (NALT)
L-Tyrosine (NALT) en América Latina
Productos disponibles en América Latina
- Mind Lab Pro7.5/10Precio local: ≈ USD 69/mes
- NooCube7/10Precio local: ≈ USD 64.99/mes
- Alpha Brain5.2/10Precio local: ≈ USD 53.30/mes
ANVISA / COFEPRIS / INVIMA
Nota regulatoria
Esta página es contenido editorial con fines educativos y no constituye consejo médico. Los suplementos alimenticios están regulados por agencias nacionales: la Agência Nacional de Vigilância Sanitária (ANVISA) en Brasil bajo RDC 243/2018, la Comisión Federal para la Protección contra Riesgos Sanitarios (COFEPRIS) en México, y el Instituto Nacional de Vigilancia de Medicamentos y Alimentos (INVIMA) en Colombia. En Argentina, la Disposición 2105/2022 de la Administración Nacional de Medicamentos, Alimentos y Tecnología Médica (ANMAT) prohíbe siete productos concretos de las marcas Newmind y PURENOOTROPICS (Noopept, F-Phenibut y Bacopa) — no recomendamos productos con Noopept ni F-Phenibut a lectores en Argentina. Aviso para lectores en Brasil: el 2 de julio de 2026, ANVISA informó que algunos péptidos inyectables promocionados en internet, entre ellos GHK-Cu, BPC-157, TB-500, CJC-1295 e ipamorelin, no están regularizados en ninguna categoría (alimento, medicamento, cosmético ni suplemento alimentario) y son ilegales para cualquier uso en salud, incluido el estético. No enlazamos ni recomendamos proveedores que realicen envíos de formulaciones inyectables a Brasil. Consulte siempre a un profesional de la salud calificado antes de comenzar cualquier suplemento. / This page is editorial and not medical advice. Supplements are regulated by national agencies: the Agência Nacional de Vigilância Sanitária (ANVISA) in Brazil, the Comisión Federal para la Protección contra Riesgos Sanitarios (COFEPRIS) in Mexico, and the Instituto Nacional de Vigilancia de Medicamentos y Alimentos (INVIMA) in Colombia. In Argentina, ANMAT Disposition 2105/2022 prohibits seven specific products of the Newmind and PURENOOTROPICS brands (Noopept, F-Phenibut and Bacopa) — we do not recommend products containing Noopept or F-Phenibut to Argentine readers. Brazil notice: on 2 July 2026, ANVISA stated that some injectable peptides promoted online, including GHK-Cu, BPC-157, TB-500, CJC-1295 and ipamorelin, are not regularised in any category (food, medicine, cosmetic or food supplement) and are illegal for any health use, including aesthetic use. We do not link to or recommend vendors that ship injectable formulations to Brazil. Consult a qualified healthcare professional before starting any supplement.
Fuentes (6)ampliar
- PMID 26424423Effect of tyrosine supplementation on clinical and healthy populations under stress or cognitive demands — A review (2015)
- PMID 10230711Tyrosine improves cognitive performance and reduces blood pressure in cadets after one week of a combat training course (1999)
- PMID 7794222The effects of tyrosine on cognitive performance during extended wakefulness (1995)
- PMID 8293316Effect of tyrosine on cognitive function and blood pressure under stress (1994)
- PMID 26285023Tyrosine Ingestion and Its Effects on Cognitive and Physical Performance in the Heat (2016)
- PMID 31521870Tyrosine negatively affects flexible-like behaviour under cognitively demanding conditions (2019)