Ashwagandha Has Been Used for Centuries. Now Researchers Are Testing It.
Ashwagandha (Withania somnifera) is one of the most studied adaptogenic herbs in the world.
Traditionally used in Ayurvedic medicine, it's often promoted for helping the body cope with stress, improve resilience, and support healthy sleep.
In recent years, multiple randomized controlled trials and systematic reviews have examined whether these traditional claims hold up under scientific scrutiny.
The results are promising.
What Is Ashwagandha?
Ashwagandha is an adaptogenic herb, meaning it may help the body adapt to physical and psychological stress.
Researchers believe some of its effects are linked to:
- Regulation of the hypothalamic-pituitary-adrenal (HPA) axis
- Reduction of excessive cortisol production
- Support for healthy nervous system function
- Modulation of GABA-related pathways involved in relaxation and sleep
Research Highlight #1: Ashwagandha May Reduce Stress and Cortisol
One of the most cited clinical studies investigated the effects of ashwagandha supplementation in adults experiencing stress.
Study | Lopresti et al., 2019
PMID: 31517876
Researchers conducted a randomized, double-blind, placebo-controlled trial and found that participants taking ashwagandha experienced significant reductions in anxiety scores and morning cortisol levels compared to placebo.
Key Finding
Ashwagandha supplementation was associated with significantly greater reductions in morning cortisol compared with placebo.
Why It Matters
Cortisol is often called the body's primary stress hormone. While cortisol is essential for healthy function, chronically elevated levels are associated with:
- Difficulty falling asleep
- Frequent nighttime waking
- Poor sleep quality
- Increased feelings of stress and anxiety
Research Highlight #2: Better Sleep Quality in Adults With Insomnia
Study | Langade et al., 2021
PMID: 32818573
In a double-blind, randomized, placebo-controlled trial, researchers evaluated ashwagandha root extract in adults experiencing sleep difficulties.
Results
Participants receiving ashwagandha showed significant improvements in:
- Sleep quality
- Sleep efficiency
- Sleep onset latency
- Overall insomnia symptoms
The researchers concluded:
"Ashwagandha root extract can improve sleep quality and can help in managing insomnia."
Why It Matters
Many sleep supplements focus only on making people sleepy.
Ashwagandha appears to work differently by helping reduce the stress response that may be preventing restorative sleep in the first place.
Research Highlight #3: Improvements in Healthy Adults
Study | Deshpande et al., 2020
PMID: 32540634
Researchers evaluated healthy adults taking ashwagandha extract in a randomized, double-blind, placebo-controlled study.
Results
Compared with placebo, participants experienced improvements in:
- Overall sleep quality
- Mental alertness upon waking
- Sleep efficiency
The improvements were particularly noticeable among participants who reported sleep concerns at baseline.
Research Highlight #4: Systematic Review and Meta-Analysis
Study | Cheah et al., 2021
PMID: 34559859
A systematic review and meta-analysis pooled results from multiple randomized controlled trials investigating ashwagandha and sleep.
Findings
Researchers concluded that:
- Ashwagandha produced a small but statistically significant improvement in sleep quality.
- Benefits were strongest in people with insomnia.
- Higher doses and longer durations tended to produce better outcomes.
Why Meta-Analyses Matter
Instead of looking at a single study, meta-analyses combine data from multiple trials, providing a stronger overview of the available evidence.
Research Highlight #5: Evidence for Stress Reduction Continues to Grow
Study | Arumugam et al., 2024
PMID: 39348746
This systematic review and meta-analysis evaluated the effects of ashwagandha on stress and anxiety outcomes.
Findings
Across multiple randomized controlled trials, ashwagandha supplementation was associated with improvements in:
- Perceived stress
- Anxiety scores
- Cortisol levels
The authors concluded that the evidence supports a beneficial effect on stress-related outcomes, while also emphasizing the need for additional high-quality long-term studies.
What the Research Suggests
Across multiple human clinical trials, researchers have consistently observed that ashwagandha may help support:
✓ Lower perceived stress
✓ Reduced cortisol levels
✓ Improved sleep quality
✓ Better sleep efficiency
✓ Reduced insomnia symptoms
✓ Improved morning alertness
However, researchers also note that additional long-term studies are still needed to better understand optimal dosing and long-term safety.
Important Note
Ashwagandha is not a sedative.
Its primary benefit appears to come from helping regulate the body's stress response rather than forcing sleep.
For people whose sleep challenges are linked to elevated stress, racing thoughts, or difficulty unwinding at night, this may be one reason researchers continue to investigate its role in sleep support.
References
- Lopresti AL et al. (2019) — A randomized, double-blind, placebo-controlled study. PMID: 31517876
- Langade D et al. (2021) — Ashwagandha root extract and sleep quality. PMID: 32818573
- Deshpande A et al. (2020) — Effects of ashwagandha extract on sleep quality in healthy adults. PMID: 32540634
- Cheah KL et al. (2021) — Systematic review and meta-analysis of ashwagandha and sleep. PMID: 34559859
- Arumugam V et al. (2024) — Effects of Ashwagandha on stress and anxiety: systematic review and meta-analysis. PMID: 39348746
This article is for educational purposes only and is not intended to diagnose, treat, cure, or prevent any disease. Always consult a qualified healthcare professional before starting any supplement regimen.