Recommended Daily Dosage of Tyrosine
For healthy adults, there is no established standard recommended daily dosage of tyrosine, but doses of 100-150 mg/kg body weight appear most beneficial for cognitive performance without adverse effects.
Dosage Recommendations Based on Age Group
Infants and Children
- Preterm infants: Minimum of 18 mg/kg per day 1
- Term infants: 94 mg/kg per day is advisable 1
- For children with specific metabolic disorders like tyrosinemia type I: 95-275 mg/day of tyrosine with careful monitoring 1
Adults
- Typical supplemental dosage: 100-150 mg/kg body weight
- Example: For a 70 kg adult, this equals approximately 7-10.5 grams per day
- Safety threshold: Doses up to 150 mg/kg appear safe for most adults, with 200 mg/kg showing potential adverse effects in older adults 2
Dosage Considerations by Purpose
Cognitive Performance Enhancement
- Optimal dosage: 100-150 mg/kg body weight
- Timing: Best taken 60-90 minutes before cognitive demands 3, 4
- Caution: Higher doses (200 mg/kg) may actually worsen cognitive performance in older adults 2
Stress Reduction
- Effective dosage: 100 mg/kg body weight has shown benefits for stress reduction 5
- Application: Most effective in short-term stressful situations rather than for chronic stress 3
Safety Considerations
Maximum Safe Dosage
- NOAEL (No Observed Adverse Effect Level):
- 600 mg/kg/day for males
- 200 mg/kg/day for females 6
Potential Side Effects at High Doses
- Edema of the cornified layer of the forestomach
- Liver changes (increased weight and hypertrophy of centrilobular hepatocytes)
- Kidney changes (increased hyaline droplets, increased urinary protein)
- Blood chemistry alterations (increases in triglycerides, cholesterol, etc.) 6
Age-Related Considerations
- Older adults (60-75 years) show higher plasma tyrosine responses to the same dose compared to younger adults
- Higher plasma tyrosine levels in older adults correlate with decreased working memory performance 2
- Consider lower dosages (100 mg/kg or less) for older adults
Clinical Application Algorithm
Determine purpose of supplementation:
- Cognitive enhancement
- Stress management
- General supplementation
Consider age and weight:
- Calculate dose based on body weight
- Reduce dose for older adults (>60 years)
Evaluate health status:
- Lower doses for those with liver or kidney conditions
- Avoid high doses in those with hypertension
Monitor response:
- Assess cognitive effects
- Watch for side effects (headache, nausea, fatigue)
Adjust as needed:
- Decrease dose if adverse effects occur
- Consider timing relative to meals (tyrosine competes with other amino acids for absorption)
Tyrosine supplementation appears most beneficial in short-term stressful or cognitively demanding situations rather than as a long-term daily supplement for general health purposes 3.