Los Angels, CA—Two new published studies are taking a look at the effects of ashwagandha (Withania somnifera) on healthy adult men. Researchers set out to determine if an eight-week therapy with Ashwagandha Root Extract (ARE) could lead to a significant improvement of male fertility, sexual wellness, and testosterone. In a separate study, researchers conducted a prospective, randomized, double-blind, placebo-controlled observational study on the safety of administered Ashwagandha Standardized Root Extract based on the incidence of treatment-emergent adverse events (TEAEs) over 12-months in healthy adults. 

Analyzing the results 

From their findings, industry experts were able to determine:

  • The long-term safety, tolerability, and quality-of-life benefits of daily Ashwagandha root extract use for one full year
  • KSM-66 demonstrated a significant improvement in serum testosterone and dihydrotestosterone levels, semen volume, sperm count, and sperm motility

Particulars of each study include:

Study: Long-Term Safety of Ashwagandha in Healthy Adults

  • Study Dose: 600 mg/day
  • Study Duration: 12 months
  • Number of Participants: 191

Results

  • Liver function markers (ALT, AST, ALP, bilirubin) remained clinically stable with no hepatotoxicity signal
  • Renal parameters (creatinine, BUN) remained within normal limits
  • Thyroid function parameters (TSH, T3, T4) remained unaffected
  • Serum cortisol levels decreased significantly (p < 0.001)
  • SF-12 Quality of Life scores improved significantly at 12 months (p < 0.001)

Participants were also evaluated for:

  • The effects of long-term Ashwagandha supplementation on hepatic safety parameters (ALT, AST, ALP, bilirubin).
  • Renal safety parameters (serum creatinine, BUN).
  • The effect on thyroid function (TSH, T3, T4).
  • Changes in serum cortisol levels, serum testosterone (free and total), changes in health-related quality of life (SF-12), and overall clinical improvement using CGI-I scale.

Study: Male Fertility, Sexual Wellness, and Testosterone in Men

  • Number of Participants: 93
  • Duration: 8 Weeks
  • Dose: 300mg / twice daily

Results

Mutha et al (2025) investigated the effects of KSM-66 Ashwagandha root extract (300mg twice daily) on 93 healthy participants over 8 weeks. In addition, there was a significant improvement in the level of sexual desire scores, number of satisfying sexual events, International Index of Erectile Function scores, and improvement in overall quality of life:

  • A 14.3% and 10.43% increase in Serum Testosterone and Dihydrotestosterone levels, respectively (p<0.05).
  • A 26.4%, 32.14%, and 37.58% increase in Semen Volume, Sperm Count, and Sperm Motility parameters, respectively.
  • A 112.84% and 108.12% increase in the Level of Sexual Desire scores and Number of Satisfying Sexual Event scores, respectively.
  • The International Index of Erectile Function domain scores for Erectile Function, Orgasmic Function, Sexual Desire, and Intercourse Satisfaction improved significantly by 12.11%, 19.03%, 31.53%, and 29% respectively. The total IIEF score improved by 18.23%.
  • A 15.52% increase in Short Form-12 Questionnaire scores for quality of life.

Complete details of the studies can be found here:

Related: New Research: Shatavari Root Provides Reproductive Support for Women

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