Beta-Sitosterol
Beta-Sitosterol (Plant sterol)
Tested only in combination with saw palmetto. Standalone AGA effect unknown.
How Beta-Sitosterol works — and how well we know it
Plant sterol with weak 5-alpha reductase inhibition activity in vitro. Included in the Prager 2002 saw palmetto + beta-sitosterol AGA trial — but the trial cannot isolate the beta-sitosterol contribution.
oral
50 mg/day in the Prager combo trial; variable in supplements.
Dietary supplement, often marketed for cholesterol reduction. Included in Folexin proprietary blend.
Cholesterol reduction (its primary indication), not AGA.
Evidence distribution across 1 claims
Why the grade is F. Included in one positive combo trial with saw palmetto, but the beta-sitosterol-specific effect cannot be isolated. No standalone AGA evidence.
Every claim, traced back to its source
We took every major claim made about Beta-Sitosterol 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: LowIncluded in Prager 2002 saw palmetto combination but not isolatedCombo trial only — standalone effect untested.
Prager 2002 RCT used a combined saw palmetto + beta-sitosterol formulation, so the beta-sitosterol contribution is not extractable.
The combination outperformed placebo. Beta-sitosterol's specific contribution is unknown.
Ingredient-claim fallacy: a positive combo trial doesn't validate either component individually.
- Prager N et al. (2002). J Altern Complement Med PMID 11975504
What's still missing from the science
- A standalone beta-sitosterol AGA RCT.
Our verdict on Beta-Sitosterol
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 Beta-Sitosterol stack up against its closest peers?
A genuine cause of reversible hair shedding in iron-deficient patients — but useless and potentially harmful if your iron stores are normal.
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.
Read the breakdown →One small Malaysian RCT showed a hair-count increase. Never replicated. Used by Nutrafol to justify its tocotrienol content.
Read the breakdown →