Top pick · DoseRank
Why this ranks #1 for free thyroxine (free t4)
#1
Swanson Vitamins, Full Spectrum® Ashwagandha, 100 Vegan Capsules (450 mg per Capsule)
Swanson Vitamins$0.14 / serving4.7 · 29,965Available now
Why this ranks here
- Evidence fitEvidence is still thin for Ashwagandha.
- Dose fitDose-range data is not available for this formula yet.
- Price / serving$0.14 per serving — low price tier for this outcome.
- AvailabilityIn stock across major retailers; 99% availability confidence.
- TrustStrong trust signals — consistently high marks from verified buyer ratings.
Trade-offs
Evidence depth trails the rest of this list
The numbers
56
57
91
84
900 mgThin evidenceevidence for this ingredient is still thin