Ashwagandha Research
Ashwagandha (Withania somnifera) is an ancient Ayurvedic adaptogenic herb extensively studied for stress reduction, anxiety relief, and hormonal balance. With over 300 clinical studies, research consistently demonstrates its effectiveness in reducing cortisol levels and improving stress response.
Last updated: October 31, 2025
Key Research Findings
Clinically significant stress and anxiety reduction
✓✓✓ Strong EvidenceMultiple randomized controlled trials show ashwagandha significantly reduces perceived stress and anxiety scores. A systematic review of 5 RCTs found consistent 30% reduction in cortisol levels and significant improvements on anxiety scales compared to placebo.
Read the Research:
Significant improvements in sleep quality and duration
✓✓ Moderate EvidenceClinical trials demonstrate ashwagandha improves both sleep onset latency and sleep quality. A meta-analysis of 5 studies found significant improvements in sleep efficiency, total sleep time, and waking after sleep onset.
Testosterone support and athletic performance enhancement
✓✓ Moderate EvidenceStudies in male subjects show ashwagandha supplementation significantly increases testosterone levels (14-40% increase), improves muscle strength, and enhances recovery. Effects are most pronounced in individuals with stress-induced low testosterone.
Featured Clinical Studies
Prospective study on stress-relieving and pharmacological actions of ashwagandha
Key Finding: 30% reduction in cortisol levels and significant improvements on stress assessment scales
Body composition and strength with ashwagandha supplementation in resistance training
Key Finding: Significant increases in muscle mass, strength, and testosterone in men undergoing resistance training
How It Works
HPA Axis Modulation
Ashwagandha modulates the hypothalamic-pituitary-adrenal (HPA) axis, reducing excessive cortisol production during stress while supporting healthy cortisol rhythm.
GABAergic Activity
Withanolides mimic GABA (gamma-aminobutyric acid) activity in the brain, producing calming effects and reducing anxiety without sedation.
Neuroprotection
Antioxidant compounds protect neurons from oxidative stress and support neuroplasticity, improving cognitive function under stress.
Thyroid Hormone Support
May increase thyroid hormone production (T3/T4), beneficial for subclinical hypothyroidism, but requires caution in hyperthyroidism.
Safety & Side Effects
Overall Safety Assessment
Excellent safety profile with minimal side effects in standardized doses (300-600mg daily)
⚠️Common Side Effects
- •Mild drowsiness in some individuals (3-5%)
- •Mild gastrointestinal upset if taken on empty stomach (2-4%)
- •Headache (rare, <2%)
🚫Contraindications
- •Pregnancy and breastfeeding
- •Hyperthyroidism (without medical supervision)
- •Autoimmune diseases (use with caution, may stimulate immune system)
- •Upcoming surgery (discontinue 2 weeks prior due to sedative effects)
Important Safety Considerations
Thyroid hormone elevation
May increase T3/T4 levels. Those with hyperthyroidism or taking thyroid medications should consult physician and monitor levels.
Low risk, but requires monitoringPregnancy and breastfeeding
Avoid during pregnancy as traditional use indicates potential uterine stimulant effects. Safety during breastfeeding not established.
Contraindicated in pregnancyResearch-Based Dosage
general stress support
300-500mg daily (standardized to 5% withanolides)
anxiety reduction
300-600mg daily, divided into 2 doses
sleep improvement
300-600mg, taken 1-2 hours before bed
athletic performance
600mg daily (higher end for men seeking testosterone support)
timing
Evening dosing preferred for sleep benefits; can split into morning/evening for anxiety
forms
Standardized root extract (KSM-66® or Sensoril®) preferred over raw powder
Medical Disclaimer
This information is for educational purposes only and is not intended as medical advice. The research presented here is compiled from peer-reviewed sources but should not replace consultation with a qualified healthcare professional. Always consult your doctor before starting any new supplement regimen, especially if you have existing health conditions or take medications.