L-Tyrosine
L-Tyrosine is an amino acid — an amino acid that can be converted into catecholamine neurotransmitters and thyroid-related compounds. 4 peer-reviewed studies are available in our database. Common forms include L-Tyrosine, N-Acetyl-L-Tyrosine.
Content reviewed by Zynava Research Team · Last updated February 2026 · Editorial policy
Find Quality L-Tyrosine Supplements
Explore l-tyrosine supplements and browse options based on ingredient research.
What Is L-Tyrosine?
An amino acid that can be converted into catecholamine neurotransmitters and thyroid-related compounds.
Key fact: NALT is a modified form often used in formulas.
L-Tyrosine Supplement Forms
L-Tyrosine is available in several supplemental forms: L-Tyrosine, N-Acetyl-L-Tyrosine. NALT is a modified form often used in formulas.
Explore L-Tyrosine Supplements
Use our research tool to explore l-tyrosine supplements and see what studies have examined.
Research Studies on L-Tyrosine
Our database contains 4 peer-reviewed studies examining l-tyrosine. Below are selected recent studies:
Related Supplements
Natural Food Sources of L-Tyrosine
L-Tyrosine can be obtained from a variety of whole foods. A food-first approach is generally recommended by nutrition experts, with supplementation considered when dietary intake is insufficient or when specific circumstances increase requirements.
- Lean meats — Complete protein sources providing all essential amino acids
- Eggs — Considered one of the highest-quality protein sources with excellent amino acid balance
- Dairy products — Whey and casein proteins contain all essential amino acids
- Legumes — Good plant-based protein sources, though may lack some essential amino acids
- Soy products — Tofu and tempeh are complete plant proteins with all essential amino acids
Dietary Context
Amino acids are the building blocks of protein and can be obtained from a wide range of protein-rich foods. Essential amino acids must come from the diet, while the body can synthesize non-essential amino acids. Individual amino acid supplements provide concentrated doses of specific amino acids, which may be useful when dietary intake is insufficient for specific purposes.
Absorption: Food vs. Supplements
Amino acids from whole food proteins are released during digestion and absorbed in the small intestine. Free-form amino acid supplements are absorbed more rapidly since they don't require digestion. However, whole food proteins provide a complete amino acid profile along with other nutrients.
Practical Tips
- A varied diet with adequate protein from multiple sources typically provides all essential amino acids
- Combining plant proteins (grains + legumes) can provide a complete amino acid profile
- Individual amino acid supplements are best taken on an empty stomach for optimal absorption
How to Take L-Tyrosine
Getting the most from l-tyrosine supplementation involves more than just choosing the right product. When and how you take it can significantly affect absorption and effectiveness.
Best time to take: On an empty stomach for individual amino acid supplements
With or Without Food
Free-form amino acids are generally best absorbed on an empty stomach (30-60 minutes before a meal or 2 hours after). This prevents competition with dietary amino acids for transport across the intestinal wall.
How Often
Once or twice daily, depending on the specific amino acid and purpose.
Practical Tips
- Take individual amino acids on an empty stomach for optimal absorption
- If stomach upset occurs, taking with a small amount of food is acceptable
- Amino acid blends and protein powders can be taken with meals
Important Interactions
- Individual amino acids may interact with certain medications — check specific amino acid guidance
- High doses of single amino acids can create imbalances — consult a provider for long-term use
- L-tryptophan and 5-HTP should not be combined with SSRI medications
This is not an exhaustive list of interactions. Always consult a healthcare provider or pharmacist about potential interactions with your specific medications and health conditions.
Where to Find L-Tyrosine Supplements
If you are considering l-tyrosine supplementation, choosing a quality product from a reputable retailer is an important step. Here are some trusted options where you can browse and compare l-tyrosine supplements.
How to Choose a Quality L-Tyrosine Supplement
- Check for third-party testing certifications (USP, NSF, or ConsumerLab) which verify potency and purity
- Compare cost per serving rather than total package price for accurate value comparison
- Read the supplement facts panel to verify the amount of active ingredient per serving
- Look for products with minimal unnecessary fillers, binders, or artificial additives
To explore supplements by ingredient or health goal, try our AI Supplement Advisor.
Research Highlights: L-Tyrosine
Researchers have investigated l-tyrosine across 2 clinical trials, 1 review, 1 meta-analysis, with publications spanning 2018 to 2023. The summaries below highlight key findings from these studies. As with all research, results should be considered within the broader body of evidence and may not apply to every individual.
Efficacy of Phenylalanine- and Tyrosine-Restricted Diet in Alkaptonuria Patients on Nitisinone Treatment: Case Series and Review of Literature
Published in Ann Nutr Metab. Study from 2022.
Source: View full study on PubMed
Nutraceutical Targeting of Placental Synthesis of Soluble Fms-Like Tyrosine Kinase- 1 (sFlt-1) as Strategy for Preventing and Controlling Pre-eclampsia
Published in Curr Pharm Des. Study from 2018.
Source: View full study on PubMed
The effect of tyrosine supplementation on whole-body endurance performance in physically active population: A systematic review and meta-analysis including GRADE qualification
Published in J Sports Sci. Study from 2023. Comprehensive analysis combining multiple studies.
Source: View full study on PubMed
Tyrosine supplementation for phenylketonuria
Published in Cochrane Database Syst Rev. Study from 2021.
Source: View full study on PubMed
The research summaries above are based on published peer-reviewed studies and are provided for informational purposes only. Study findings may not apply to all individuals, and the presence of a study summary does not constitute an endorsement of l-tyrosine for any specific health condition. Always consult a qualified healthcare professional before making decisions based on research findings.
Important Information
Our Evidence-Based Approach to Supplement Information
Zynava uses a structured evidence grading system to evaluate supplement research. We categorize evidence based on study quality, sample size, consistency of results across multiple trials, and whether findings have been replicated by independent research groups. Our system distinguishes between strong evidence from large randomized controlled trials, moderate evidence from smaller studies, and preliminary evidence from animal or in-vitro research.
We believe consumers deserve to know not just what a study found, but how reliable that finding is. A single small study suggesting a benefit is very different from a dozen large trials confirming it. Our evidence grades help you quickly assess where the science stands for any given supplement and health outcome, so you can have more productive conversations with your healthcare provider.
Why Supplement Needs Are Highly Individual
No two people have identical supplement needs. Factors that influence which supplements may be beneficial for you include your diet and nutritional gaps, genetic variations that affect nutrient metabolism, your age and life stage, activity level, geographic location (which affects vitamin D synthesis), existing health conditions, and current medications. What works well for one person may be unnecessary or even counterproductive for another.
This is why Zynava provides information and tools rather than one-size-fits-all suggestions. Our Supplement Advisor asks about your individual circumstances to provide more relevant options, but even filtered results are starting points — not replacements for professional guidance. We encourage every user to work with their healthcare provider to develop a supplement plan that is tailored to their unique needs and regularly reassessed as those needs change.
This content is for general educational purposes only and is not intended as medical advice. Consult a healthcare professional before starting any supplement. Individual results may vary. See our full disclaimer and affiliate disclosure.