Meta Information
ID:l-theanine
Name:L-Theanine
Schema Version:1.5
Alternate Names
- Theanine
- gamma-glutamylethylamide
Intervention Type
therapeutic_agent
Expected Cost Mean
Low Cost:
5
High Cost:
30
Cost Type:
monthly
Description:
Widely available over-the-counter supplement; not covered by insurance.
Summary
L-Theanine is an amino acid found primarily in tea leaves that readily crosses the blood-brain barrier. It increases alpha brain wave activity, promoting a state of relaxed alertness, and modulates neurotransmitters like GABA and serotonin. Its primary healthspan relevance lies in its ability to mitigate chronic stress and improve sleep quality, both of which are foundational for maintaining long-term neurological health and metabolic function.
Purpose
An amino acid for stress reduction and improved sleep quality.
Card Summary
An amino acid found in tea that promotes relaxed alertness, reduces stress, and may improve sleep quality, indirectly supporting cognitive healthspan.
Drug Class
Drugs In Class
Empty Array
Impact
Score:
4.5
Justification:
Effective for specific pathways like stress reduction and sleep quality improvement.
Evidence
Grade:
A
Score:
8.5
Justification:
Multiple human RCTs and meta-analyses confirm its effects on stress and cognition.
Safety
Score:
2.5
Justification:
GRAS status with an excellent safety profile and minimal reported side effects.
Flags
- May interact with blood pressure medications, potentially increasing their effects.
- Can interact with stimulant medications due to its calming effects.
- High doses may cause mild headaches or dizziness in sensitive individuals.
Verdict
A safe, effective tool for managing stress and improving sleep quality.
Created
2026-04-26T18:04:14.818365Z
Model
Gemini 3.1 Pro (High)
Delivery
Route:
oral
Scope:
- systemic
Indication
Focus:
healthspan
Description:
L-Theanine is an amino acid found primarily in tea leaves that readily crosses the blood-brain barrier. It increases alpha brain wave activity, promoting a state of relaxed alertness, and modulates ne...
Typical Protocol
- Take 100-200 mg once or twice daily, often with caffeine to mitigate jitters.
- Consider 200-400 mg about 30-60 minutes before bedtime to support sleep quality.