Head-to-head · stress
Ashwagandha vs. Slow-Paced Breathing for Stress
Outcome compared: Stress & anxiety reduction
The verdict
Comparable directional evidence, but ashwagandha's effect size is inflated by high study heterogeneity, while breathing's physiological mechanism (vagal/HRV) is more consistently replicated. Breathing is free, has a faster onset (minutes vs. weeks), and has no contraindications for healthy adults — ashwagandha requires medical caution around thyroid function and pregnancy.
The gapRoughly comparable grades (B- vs. B), but very different risk/cost profiles for similar benefit.
B-
- Evidence grade
- B−
- Effect size
- Large but heterogeneous — anxiety SMD −1.55 (I² = 83–94%)
- Evidence base
- 9–15 RCTs; high heterogeneity
- Onset & cost
- Weeks; supplement cost
- Cautions
- Avoid in pregnancy, thyroid meds, autoimmune
B
- Evidence grade
- B
- Effect size
- Moderate & consistent — BP SMD −0.45, HRV improved
- Evidence base
- Multiple independent CV/HRV meta-analyses
- Onset & cost
- Minutes; free
- Cautions
- None significant for healthy adults
Grade badges show each intervention's strongest evidence across all its outcomes. Tap a name for the full entry.