Supplement
GABA is the main calming chemical messenger in the brain, where it dampens nerve activity, though little of the supplement may cross into the brain. People look at it mostly for anxiety, such as fear of flying, and the evidence is limited: studies found anxiety symptoms went down and people fell asleep sooner. Most of these studies were small, so the results are early.
- Updated
- How we grade
- 2 studies cited
- Best evidence
- Grade C
- Conditions studied
- 6
- Outcomes
- 7
- Graded outcomes
- 0052
Evidence by condition
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Sleep Latency Moderate Decrease - 100mg GABA reduced time to fall asleep | Improves (the measure goes down) | Moderate effect | 120 people | |||
| Non-REM Sleep Duration Small Increase in non-REM sleep duration | Improves (the measure goes up) | Small effect | 60 people |
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Anxiety Symptoms Small Decrease in anxiety measures | Improves (the measure goes down) | Small effect | 60 people |
Depression
- Depression Symptoms: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Depression Symptoms Improvement in depression scores (90-day trial with exercise) | Improves (the measure goes down) | Moderate effect | 30 people |
Exercise Performance
- Growth Hormone: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Growth Hormone Transient increase in GH with 3-5g doses | Improves (the measure goes up) | Moderate effect | 45 people |
Stress
- Stress Markers: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Stress Markers Limited evidence for stress reduction | Improves (the measure goes down) | Small effect | 80 people |
Blood Pressure
- Blood Pressure: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Blood Pressure Modest decrease with 10mg GABA from fermented milk (limited evidence) | Improves (the measure goes down) | Small effect | 39 people |
Key findings
- Sleep LatencyImproves (the measure goes down)
- Non-REM Sleep DurationImproves (the measure goes up)
- Anxiety SymptomsImproves (the measure goes down)
Studies cited
2 studies from PubMed