Does ashwagandha actually raise testosterone?

Ashwagandha (Withania somnifera, specifically KSM-66 or Sensoril root extract) at 300–600 mg/day has been shown in several small RCTs to increase total testosterone by approximately 10–22% in men with suboptimal testosterone and high chronic stress, the proposed mechanism involves HPA axis modulation reducing cortisol, which secondarily allows testosterone production to recover from cortisol-induced suppression (Wankhede et al., J Int Soc Sports Nutr, 2015).

The 10–22% range from RCT data is a real effect in the specific populations studied (men with documented stress and cortisol elevation, not men with primary hypogonadism). For a man with a testosterone of 400 ng/dL, a 15% increase brings him to approximately 460 ng/dL, still within the normal range but potentially symptomatically meaningful. This is not TRT-equivalent effect. A man with confirmed hypogonadism (below 300 ng/dL with symptoms) cannot replace TRT with ashwagandha. A man with cortisol-suppressed testosterone may see genuine improvement.

Honesty Scale: Promising (2) for ashwagandha increasing testosterone in stressed men with cortisol-mediated testosterone suppression. Unsupported (5) as a replacement for TRT in confirmed hypogonadism.

What to do: Ashwagandha KSM-66 at 300 mg twice daily is a reasonable 90-day trial for men with suspected cortisol-suppressed testosterone and high chronic stress, before pursuing hormonal evaluation. If testosterone remains symptomatic after 90 days of lifestyle optimization plus ashwagandha, pursue a proper endocrine evaluation.

For the full picture, read The Supplementation Deep Dive