Does Ashwagandha supplementation affect testosterone levels?

Ashwagandha and Testosterone Levels

Ashwagandha supplementation can modestly increase testosterone levels in men, particularly in those with lower baseline testosterone levels, though the clinical significance of this effect remains limited.

Evidence on Ashwagandha and Testosterone

Effects on Testosterone Levels

• Multiple randomized controlled trials have demonstrated that ashwagandha (Withania somnifera) supplementation can increase testosterone levels:
  • An 8-week study using standardized ashwagandha root extract (Shoden beads) showed a 14.7% greater increase in testosterone compared to placebo in overweight men aged 40-70 years 1
  • Another 8-week trial using 300 mg of ashwagandha root extract twice daily demonstrated a statistically significant increase in serum testosterone levels in men with lower sexual desire 2
  • A systematic review identified ashwagandha root and root/leaf extracts as having positive effects on testosterone concentrations in men 3

Mechanism of Action

• Ashwagandha appears to influence testosterone levels through modulation of the hypothalamic-pituitary-adrenal (HPA) axis:
  • Research shows ashwagandha supplementation is associated with reductions in morning cortisol levels 4
  • The herb may help reduce stress, which can indirectly support healthy testosterone production 4

Clinical Context and Limitations

Magnitude of Effect

• The testosterone increases from ashwagandha are modest compared to pharmaceutical testosterone replacement therapy
• Most studies showing positive effects were conducted in specific populations:
  • Men with lower baseline testosterone
  • Men with self-reported stress or fatigue
  • Overweight men aged 40-70

Quality of Evidence

• While several studies show positive effects, the overall evidence quality is moderate:
  • Sample sizes in most studies are relatively small
  • Study durations are typically short (8-16 weeks)
  • Various extracts and dosages have been used across studies
  • Long-term effects remain largely unknown

Comparison to Pharmaceutical Testosterone Therapy

• Pharmaceutical testosterone therapy produces more substantial and reliable increases in testosterone levels 5
• Medical guidelines focus on pharmaceutical testosterone replacement for clinically significant hypogonadism rather than herbal supplements 5
• The American College of Physicians recommends pharmaceutical testosterone therapy for men with age-related low testosterone who have sexual dysfunction 5

Practical Considerations

Dosing

• Effective dosages in studies ranged from:
  • 300 mg twice daily of root extract 2
  • Standardized extracts delivering approximately 21 mg of withanolide glycosides daily 1

Safety Profile

• Ashwagandha appears to have a favorable short-term safety profile with few reported adverse effects in clinical trials
• Unlike pharmaceutical testosterone therapy, ashwagandha has not been associated with:
  • Erythrocytosis (elevated red blood cell count) 5, 6
  • Testicular atrophy 6
  • Suppression of spermatogenesis 6
  • Prostate issues 5, 6

Appropriate Use

• Ashwagandha may be most appropriate for:
  • Men with mild testosterone deficiency symptoms
  • Those concerned about fertility (unlike pharmaceutical testosterone which can suppress spermatogenesis) 6
  • As an adjunctive approach alongside lifestyle modifications 7

Bottom Line

Ashwagandha supplementation appears to modestly increase testosterone levels, particularly in men with lower baseline levels. However, the clinical significance of these increases is uncertain, and the evidence quality is not as robust as for pharmaceutical testosterone therapy. For men with clinically significant hypogonadism, pharmaceutical testosterone therapy remains the standard of care, while ashwagandha may be considered as a complementary approach, particularly for those with milder symptoms or concerns about fertility.