NutrimatchThe Top 7 Benefits of Ashwagandha
Key takeaways
- Strong evidence for reducing anxiety and building muscle strength — among the best-evidenced effects of any single supplement.
- Most effects are mediated by cortisol reduction, making it most relevant for people under sustained stress.
- Effects take 4–8 weeks to appear; all major trials run 8–12 weeks.
Ashwagandha is a root herb that has been used in traditional Indian medicine for thousands of years. It reduces the amount of cortisol — the hormone the body releases under pressure — resulting in a calmer stress response. Most people notice a difference after two to four weeks of regular use. It is usually taken as a capsule once or twice a day.
Ashwagandha as a supplement is a herb derived from plant root, commonly taken as capsule or powder. Studies typically use 300–600mg.
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There is strong evidence that Ashwagandha improves anxiety symptoms, with Examine.com rating the evidence as grade A.
Multiple randomised controlled trials have found that ashwagandha significantly reduces validated anxiety scores compared to placebo over 8–12 weeks. The effect is one of the most consistently replicated in ashwagandha research and is thought to be mediated primarily by reductions in cortisol. Examine.com rates the evidence as Grade A.
2. Building muscle strength
There is strong evidence that Ashwagandha improves power output, with Examine.com rating the evidence as grade A.
Several controlled trials in resistance-trained adults have found that ashwagandha increases both muscle strength and size compared to placebo when combined with a training programme. In one 8-week trial, participants taking ashwagandha made significantly greater gains in bench press and leg extension strength. The effect appears to be mediated partly through testosterone and improved recovery between sessions.
3. Managing chronic stress
There is strong evidence that Ashwagandha improves cortisol, with Examine.com rating the evidence as grade A.
Ashwagandha is classified as an adaptogen — a compound that helps the body maintain a more stable physiological response to sustained stress. Human trials consistently show meaningful reductions in self-reported stress scores and salivary cortisol levels over 8–12 weeks. The evidence is consistent across multiple adult populations, particularly those with clinically elevated baseline stress.
4. Improving executive function
There is good evidence that Ashwagandha improves executive function, with Examine.com rating the evidence as grade B.
Several trials have found that ashwagandha improves performance on tests of executive function — the processes involved in planning, organising and switching between tasks — particularly in adults experiencing stress. Studies typically run for 8–12 weeks. The mechanism may involve cortisol reduction, since chronically elevated cortisol is known to impair prefrontal cortex performance.
5. Increasing stamina
There is good evidence that Ashwagandha improves aerobic exercise metrics, with Examine.com rating the evidence as grade B.
Ashwagandha has been studied in both competitive athletes and untrained individuals for effects on sustained physical performance. Trials consistently show improvements in endurance capacity over 8–12 weeks, with some studies also finding faster recovery between exercise bouts. The effect size is moderate but has been replicated across multiple independent trials in different populations.
6. Improving exercise endurance
There is good evidence that Ashwagandha improves aerobic exercise metrics, with Examine.com rating the evidence as grade B.
Several trials have found that ashwagandha improves aerobic capacity — measured as VO₂ max — in both trained athletes and untrained adults. In an 8-week study, participants taking ashwagandha showed significantly greater improvements in cardiorespiratory endurance than the placebo group. The mechanism is not fully established but may involve improved oxygen delivery and reduced exercise-induced fatigue markers.
7. Lowering triglycerides
There is good evidence that Ashwagandha improves triglycerides, with Examine.com rating the evidence as grade B.
A number of human trials have observed reductions in blood triglyceride levels following ashwagandha supplementation, typically over 8–12 weeks. The effect is moderate and appears alongside broader lipid changes in some studies. Examine.com rates the evidence as Grade B, based on multiple trials with generally consistent direction.
How we ranked these
Benefit rankings are based on evidence grades from Examine.com. Grade A indicates strong, replicated evidence from multiple human trials. Grade B indicates good evidence from fewer or smaller studies. Grade C indicates limited or early-stage research. All grade A and B benefits are shown. Grade C benefits are only included to reach a minimum of five entries — if five or more grade A/B benefits exist, no grade C results appear.
This article is for informational purposes only and does not constitute medical advice. Consult a healthcare professional before starting any supplement, particularly if you take medication or have a medical condition. Evidence grades are sourced from Examine.com and reflect the state of research at time of publication.