L-Tyrosine (Thyroid Substrate)
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L-Tyrosine (Thyroid Substrate). Amino acid substrate paired with iodine to form thyroid hormones.
How it works. Tyrosine + iodine → MIT/DIT → T4/T3.
What the research supports. 1 graded claims. Strongest: Cognitive support under stress (moderate).
How much to take. Typical dose: 500–1500 mg AM.
Side effects and interactions. 1 medication interaction listed. Serious: Discontinue and seek medical advice if symptoms are severe, persistent, or include difficulty breathing.
Stacking. Pairs well with A high-quality multivitamin, Omega-3 (EPA/DHA).
Common forms. Available as Free-form crystalline powder, Capsules or tablets, Pre-mixed recovery or hydration beverages, Time-release formulations.
Key studies. 8 studies cited. The strongest are listed with links to PubMed.
Community. Experiences from people who have tried L-Tyrosine (Thyroid Substrate). Anecdotes are not medical advice.
L-Tyrosine (Thyroid Substrate). Amino acid substrate paired with iodine to form thyroid hormones.
What it is
Amino acid substrate paired with iodine to form thyroid hormones.
Food sources
Goals
How it works
Tyrosine + iodine → MIT/DIT → T4/T3.
Pathways
- Tyrosine + iodine → MIT/DIT → T4/T3
Effects
- +Cognitive support under stress supports
What the research supports
Strong: consistent results across large trials or meta-analyses. Moderate: several trials, mostly positive. Limited: small or mixed studies. Preclinical: animal or cell research only.
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Side effects & interactions
Common side effects
- L-Tyrosine (Thyroid Substrate) is generally well-tolerated at evidence-based doses
- Mild GI discomfort (nausea, loose stools, or bloating) possible at higher intakes
- Headache or transient fatigue reported by a small fraction of users
Serious
- Discontinue and seek medical advice if symptoms are severe, persistent, or include difficulty breathing
Medication interactions
Hypertensive crisis risk.
Check any supplement–medication combination with your pharmacist before starting.
Combines with
Pairs well
- A high-quality multivitaminCovers micronutrient cofactors that support most supplement pathways.
- Omega-3 (EPA/DHA)Foundational anti-inflammatory support that complements most regimens.
Common forms
- Free-form crystalline powder
- Capsules or tablets
- Pre-mixed recovery or hydration beverages
- Time-release formulations
Key studies
8 studies cited in total.
Opens current human and preclinical literature matching L-Tyrosine (Thyroid Substrate) and "Cognitive support under stress". Filter by RCT, meta-analysis, or year on the results page.
Opens current human and preclinical literature matching L-Tyrosine (Thyroid Substrate) and "randomized controlled trial". Filter by RCT, meta-analysis, or year on the results page.
Opens current human and preclinical literature matching L-Tyrosine (Thyroid Substrate) and "meta-analysis". Filter by RCT, meta-analysis, or year on the results page.
Discussion
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