Horsetail
Horsetail (Equisetum arvense)
Traditional silica source with no quality AGA evidence.
How Horsetail works — and how well we know it
Source of dietary silica; the claim is that silica supports keratin and hair shaft strength. Mechanism is non-specific and the dose-response is poorly characterized.
oral
Variable; included in proprietary blends at undisclosed doses.
Traditional silica source. No regulatory approval for AGA.
Nothing AGA-specific.
Evidence distribution across 1 claims
Why the grade is F. No quality AGA RCT. Mechanism is generic ('silica is good for hair') and the dose required for any biochemical effect is unclear.
Every claim, traced back to its source
We took every major claim made about Horsetail and matched it to the specific experimental model behind it. Click a claim to see the model, the finding, and our assessment of how much weight it deserves.
1 claims · evidence-by-evidence breakdown
1Open-LabelWeight: LowHorsetail's AGA claim rests on the generic 'silica supports hair' inferenceNo evidence to assess.
Absence of quality AGA trials in indexed medical literature.
No peer-reviewed RCT supports horsetail for AGA.
Filler ingredient typical of supplement-bundle formulations.
What's still missing from the science
- Any AGA-specific evidence.
Our verdict on Horsetail
Not in our formulary yet
We don't carry this ingredient. We only formulate around actives where the evidence — and the safety profile — is strong enough to recommend with confidence. As the data matures, we may revisit.
Related treatments
How does Horsetail stack up against its closest peers?
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Read the breakdown →A botanical 5-alpha reductase inhibitor whose only high-quality trials (in BPH) showed no benefit over placebo; the positive AGA data are small and low-quality.
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