Evidence-based effects and studies
Detailed analysis of research findings
8-week randomized placebo-controlled trial in athletic adults reporting significant improvements in VO2max, recovery scores, and antioxidant markers with ashwagandha (300 mg twice daily); no adverse events reported.
In healthy adults with mild–moderate stress, 500 mg Ashwagandha root extract daily for 60 days reduced perceived stress and anxiety scores, improved quality of life and some cognitive measures, and lowered morning salivary cortisol.
120 overweight/mildly obese adults (age 40–75) randomized; analysis set ≈111 (55 ash, 56 placebo) took 200 mg twice daily for 12 weeks; primary outcome (PSS) improved in both groups with no between-group difference, but fatigue (CFS) improved more with ashwagandha and HRV and some sex-hormone changes were observed.
Adjunctive ashwagandha reduced negative, general, and total PANSS symptoms and perceived stress versus placebo; inflammatory markers changed non-significantly.
Two double-blind intervention studies (pilot n=32 and crossover n=110) in older healthy volunteers showed that tea fortified with several Ayurvedic herbs including Withania somnifera increased natural killer (NK) cell activity compared with regular tea.
One-month randomized double-blind trial of Withania somnifera extract in schizophrenia patients with metabolic syndrome showed reductions in fasting glucose and triglycerides vs placebo.
Triple-blind RCT in 100 infertile men comparing Ashwagandha (5 g/day) vs pentoxifylline for 90 days; sperm count, progressive motility and morphology improved from baseline with Ashwagandha; no major adverse events and no significant differences between groups after treatment.
Triple-blind RCT in 100 infertile men comparing Ashwagandha (5 g/day) vs pentoxifylline for 90 days; sperm count, progressive motility and morphology improved from baseline with Ashwagandha; no major adverse events and no significant differences between groups after treatment.
Pilot randomized trial in subclinical hypothyroid adults (50 randomized, 4 withdrew) given 600 mg daily for 8 weeks; thyroid function markers (TSH, T3, T4) improved versus placebo.
60 mildly stressed healthy adults took 240 mg daily for 60 days; ashwagandha reduced anxiety and cortisol, lowered DHEA-S, and increased testosterone in men; well tolerated.
16-week randomized double-blind crossover pilot in overweight men (40–70 yrs) showing increases in salivary DHEA-S and testosterone during ashwagandha intake (effects diminished after cessation); no significant cortisol or symptom (fatigue/vigor) advantage over placebo.
One-month randomized double-blind trial of Withania somnifera extract in schizophrenia patients with metabolic syndrome showed reductions in fasting glucose and triglycerides vs placebo.
80 healthy adults randomized to 300 mg twice daily for 8 weeks; no adverse events and no clinically significant changes in hematology, biochemistry, or thyroid profile were observed.
8-week randomized double-blind placebo-controlled dose-ranging trial (125/250/500 mg) in chronically stressed adults showing dose-dependent reductions in perceived stress, HPA-axis biomarkers and some inflammatory cytokines, with good safety.
A polyherbal (includes Ashwagandha) reduced illness duration, several symptom severities, and IL-6 versus placebo in hospitalized moderate COVID-19 patients; attribution to Ashwagandha alone is unclear.
Interim analysis (first 160 completers, 8 weeks) of a randomized open-label trial in HCWs showed Ashwagandha (250 mg twice daily) was non-inferior to weekly HCQ for preventing symptomatic RT-PCR-confirmed COVID-19 and had fewer mild adverse events.
16-week randomized double-blind crossover pilot in overweight men (40–70 yrs) showing increases in salivary DHEA-S and testosterone during ashwagandha intake (effects diminished after cessation); no significant cortisol or symptom (fatigue/vigor) advantage over placebo.
50 healthy young men undergoing resistance training took 300 mg twice daily for 8 weeks; ashwagandha augmented gains in strength, muscle size, testosterone, and recovery versus placebo.
Double‑blind randomized placebo‑controlled pilot trial of a multi‑component Ayurvedic regimen (includes Ashwagandha) in RT‑PCR positive asymptomatic/mild COVID‑19 patients: treatment group showed faster virological clearance and lower inflammatory marker rises.
8-week double-blind RCT in adults under chronic stress: Ashwagandha (300 mg twice daily) improved stress-related measures and outcomes related to eating and weight management with good tolerability.
One-month randomized double-blind trial of Withania somnifera extract in schizophrenia patients with metabolic syndrome showed reductions in fasting glucose and triglycerides vs placebo.
60 mildly stressed healthy adults took 240 mg daily for 60 days; ashwagandha reduced anxiety and cortisol, lowered DHEA-S, and increased testosterone in men; well tolerated.
60 mildly stressed healthy adults took 240 mg daily for 60 days; ashwagandha reduced anxiety and cortisol, lowered DHEA-S, and increased testosterone in men; well tolerated.
60 mildly stressed healthy adults took 240 mg daily for 60 days; ashwagandha reduced anxiety and cortisol, lowered DHEA-S, and increased testosterone in men; well tolerated.
60 mildly stressed healthy adults took 240 mg daily for 60 days; ashwagandha reduced anxiety and cortisol, lowered DHEA-S, and increased testosterone in men; well tolerated.
50 healthy young men undergoing resistance training took 300 mg twice daily for 8 weeks; ashwagandha augmented gains in strength, muscle size, testosterone, and recovery versus placebo.
50 healthy young men undergoing resistance training took 300 mg twice daily for 8 weeks; ashwagandha augmented gains in strength, muscle size, testosterone, and recovery versus placebo.
50 healthy young men undergoing resistance training took 300 mg twice daily for 8 weeks; ashwagandha augmented gains in strength, muscle size, testosterone, and recovery versus placebo.
50 healthy young men undergoing resistance training took 300 mg twice daily for 8 weeks; ashwagandha augmented gains in strength, muscle size, testosterone, and recovery versus placebo.
Pilot randomized trial in subclinical hypothyroid adults (50 randomized, 4 withdrew) given 600 mg daily for 8 weeks; thyroid function markers (TSH, T3, T4) improved versus placebo.
Pilot randomized trial in subclinical hypothyroid adults (50 randomized, 4 withdrew) given 600 mg daily for 8 weeks; thyroid function markers (TSH, T3, T4) improved versus placebo.
In healthy adults with mild–moderate stress, 500 mg Ashwagandha root extract daily for 60 days reduced perceived stress and anxiety scores, improved quality of life and some cognitive measures, and lowered morning salivary cortisol.
In healthy adults with mild–moderate stress, 500 mg Ashwagandha root extract daily for 60 days reduced perceived stress and anxiety scores, improved quality of life and some cognitive measures, and lowered morning salivary cortisol.
120 overweight/mildly obese adults (age 40–75) randomized; analysis set ≈111 (55 ash, 56 placebo) took 200 mg twice daily for 12 weeks; primary outcome (PSS) improved in both groups with no between-group difference, but fatigue (CFS) improved more with ashwagandha and HRV and some sex-hormone changes were observed.
120 overweight/mildly obese adults (age 40–75) randomized; analysis set ≈111 (55 ash, 56 placebo) took 200 mg twice daily for 12 weeks; primary outcome (PSS) improved in both groups with no between-group difference, but fatigue (CFS) improved more with ashwagandha and HRV and some sex-hormone changes were observed.
120 overweight/mildly obese adults (age 40–75) randomized; analysis set ≈111 (55 ash, 56 placebo) took 200 mg twice daily for 12 weeks; primary outcome (PSS) improved in both groups with no between-group difference, but fatigue (CFS) improved more with ashwagandha and HRV and some sex-hormone changes were observed.
120 overweight/mildly obese adults (age 40–75) randomized; analysis set ≈111 (55 ash, 56 placebo) took 200 mg twice daily for 12 weeks; primary outcome (PSS) improved in both groups with no between-group difference, but fatigue (CFS) improved more with ashwagandha and HRV and some sex-hormone changes were observed.
80 healthy adults randomized to 300 mg twice daily for 8 weeks; no adverse events and no clinically significant changes in hematology, biochemistry, or thyroid profile were observed.
80 healthy adults randomized to 300 mg twice daily for 8 weeks; no adverse events and no clinically significant changes in hematology, biochemistry, or thyroid profile were observed.
8-week randomized placebo-controlled trial showing improved sleep measures in both healthy and insomnia participants; better effects in insomnia group; well tolerated.
8-week randomized placebo-controlled trial showing improved sleep measures in both healthy and insomnia participants; better effects in insomnia group; well tolerated.
6-week randomized double-blind RCT in adults with non-restorative sleep: 120 mg daily ashwagandha improved sleep and quality of life with no treatment-related adverse events.
8-week randomized placebo-controlled trial showing improved sleep measures in both healthy and insomnia participants; better effects in insomnia group; well tolerated.
6-week randomized double-blind RCT in adults with non-restorative sleep: 120 mg daily ashwagandha improved sleep and quality of life with no treatment-related adverse events.
8-week randomized double-blind placebo-controlled dose-ranging trial (125/250/500 mg) in chronically stressed adults showing dose-dependent reductions in perceived stress, HPA-axis biomarkers and some inflammatory cytokines, with good safety.
8-week randomized double-blind placebo-controlled dose-ranging trial (125/250/500 mg) in chronically stressed adults showing dose-dependent reductions in perceived stress, HPA-axis biomarkers and some inflammatory cytokines, with good safety.
8-week randomized placebo-controlled study in perimenopausal women showing reduced menopausal symptoms and favorable changes in sex hormones; well tolerated.
8-week randomized placebo-controlled study in perimenopausal women showing reduced menopausal symptoms and favorable changes in sex hormones; well tolerated.
8-week randomized placebo-controlled study in perimenopausal women showing reduced menopausal symptoms and favorable changes in sex hormones; well tolerated.
8-week randomized double-blind placebo-controlled trial in resistance-trained adults showing greater gains in muscle strength, muscle size, and VO2max with ashwagandha plus resistance training; well tolerated.
8-week randomized double-blind placebo-controlled trial in resistance-trained adults showing greater gains in muscle strength, muscle size, and VO2max with ashwagandha plus resistance training; well tolerated.
8-week randomized double-blind placebo-controlled trial in resistance-trained adults showing greater gains in muscle strength, muscle size, and VO2max with ashwagandha plus resistance training; well tolerated.
Double-blind placebo-controlled study (acute + 30-day liposomal ashwagandha 225 mg/day) in healthy adults showing acute improvements in reaction time (picture recognition) and reductions in tension/fatigue after supplementation; blood markers remained within normal ranges.
Double-blind placebo-controlled study (acute + 30-day liposomal ashwagandha 225 mg/day) in healthy adults showing acute improvements in reaction time (picture recognition) and reductions in tension/fatigue after supplementation; blood markers remained within normal ranges.
Double-blind placebo-controlled study (acute + 30-day liposomal ashwagandha 225 mg/day) in healthy adults showing acute improvements in reaction time (picture recognition) and reductions in tension/fatigue after supplementation; blood markers remained within normal ranges.
8-week randomized placebo-controlled trial in athletic adults reporting significant improvements in VO2max, recovery scores, and antioxidant markers with ashwagandha (300 mg twice daily); no adverse events reported.
8-week randomized placebo-controlled trial in athletic adults reporting significant improvements in VO2max, recovery scores, and antioxidant markers with ashwagandha (300 mg twice daily); no adverse events reported.
16-week randomized double-blind crossover pilot in overweight men (40–70 yrs) showing increases in salivary DHEA-S and testosterone during ashwagandha intake (effects diminished after cessation); no significant cortisol or symptom (fatigue/vigor) advantage over placebo.
6-week randomized double-blind RCT in adults with non-restorative sleep: 120 mg daily ashwagandha improved sleep and quality of life with no treatment-related adverse events.
8-week randomized double-blind placebo-controlled pilot in adults with mild cognitive impairment: ashwagandha root extract (300 mg twice daily) improved multiple memory and cognitive test scores.
8-week randomized double-blind placebo-controlled pilot in adults with mild cognitive impairment: ashwagandha root extract (300 mg twice daily) improved multiple memory and cognitive test scores.
8-week randomized double-blind placebo-controlled pilot in adults with mild cognitive impairment: ashwagandha root extract (300 mg twice daily) improved multiple memory and cognitive test scores.
30-day double-blind RCT in college students (700 mg/day): ashwagandha improved adjusted sleep scores and reduced food cravings versus placebo; stress effects were less clear in short duration.
30-day double-blind RCT in college students (700 mg/day): ashwagandha improved adjusted sleep scores and reduced food cravings versus placebo; stress effects were less clear in short duration.
8-week double-blind RCT in adults under chronic stress: Ashwagandha (300 mg twice daily) improved stress-related measures and outcomes related to eating and weight management with good tolerability.
8-week double-blind RCT in adults under chronic stress: Ashwagandha (300 mg twice daily) improved stress-related measures and outcomes related to eating and weight management with good tolerability.
12-week randomized double-blind placebo-controlled trial in recreationally active men (500 mg/day Sensoril®) showed greater gains in strength, power, and perceived recovery versus placebo.
12-week randomized double-blind placebo-controlled trial in recreationally active men (500 mg/day Sensoril®) showed greater gains in strength, power, and perceived recovery versus placebo.
12-week randomized double-blind placebo-controlled trial in recreationally active men (500 mg/day Sensoril®) showed greater gains in strength, power, and perceived recovery versus placebo.
90-day randomized double-blind placebo-controlled trial in adults with mild–moderate depression/anxiety: 500 mg standardized root extract with piperine improved depression, anxiety, sleep quality, QOL and increased serum serotonin; all completers (n=70).
90-day randomized double-blind placebo-controlled trial in adults with mild–moderate depression/anxiety: 500 mg standardized root extract with piperine improved depression, anxiety, sleep quality, QOL and increased serum serotonin; all completers (n=70).
90-day randomized double-blind placebo-controlled trial in adults with mild–moderate depression/anxiety: 500 mg standardized root extract with piperine improved depression, anxiety, sleep quality, QOL and increased serum serotonin; all completers (n=70).
Randomized double‑blind placebo‑controlled 28‑day trial in professional female footballers: 600 mg/day root extract improved perceived recovery and sleep and showed greater hand‑grip strength increases versus placebo.
Randomized double‑blind placebo‑controlled 28‑day trial in professional female footballers: 600 mg/day root extract improved perceived recovery and sleep and showed greater hand‑grip strength increases versus placebo.
Randomized double‑blind placebo‑controlled 28‑day trial in professional female footballers: 600 mg/day root extract improved perceived recovery and sleep and showed greater hand‑grip strength increases versus placebo.
Randomized trial comparing a multi‑herb Unani formulation (contains Withania somnifera among other herbs) to celecoxib for RA; per‑protocol analysis on 50 completers found no clear superiority or inferiority.
Randomized trial comparing a multi‑herb Unani formulation (contains Withania somnifera among other herbs) to celecoxib for RA; per‑protocol analysis on 50 completers found no clear superiority or inferiority.
Double‑blind randomized placebo‑controlled pilot trial of a multi‑component Ayurvedic regimen (includes Ashwagandha) in RT‑PCR positive asymptomatic/mild COVID‑19 patients: treatment group showed faster virological clearance and lower inflammatory marker rises.
Double‑blind randomized placebo‑controlled pilot trial of a multi‑component Ayurvedic regimen (includes Ashwagandha) in RT‑PCR positive asymptomatic/mild COVID‑19 patients: treatment group showed faster virological clearance and lower inflammatory marker rises.
60‑day randomized double‑blind trial of proprietary blend (Withania somnifera + Abelmoschus extracts) in adults with functional constipation: significant symptom, transit and biomarker improvements versus placebo.
60‑day randomized double‑blind trial of proprietary blend (Withania somnifera + Abelmoschus extracts) in adults with functional constipation: significant symptom, transit and biomarker improvements versus placebo.
60‑day randomized double‑blind trial of proprietary blend (Withania somnifera + Abelmoschus extracts) in adults with functional constipation: significant symptom, transit and biomarker improvements versus placebo.
Randomized double‑blind placebo‑controlled 60‑day pilot trial of a standardized Ashwagandha extract (Somin‑On™) in adults with MCI: significant improvements in multiple memory and cognitive measures versus placebo.
Randomized double‑blind placebo‑controlled 60‑day pilot trial of a standardized Ashwagandha extract (Somin‑On™) in adults with MCI: significant improvements in multiple memory and cognitive measures versus placebo.
Randomized double‑blind placebo‑controlled 60‑day pilot trial of a standardized Ashwagandha extract (Somin‑On™) in adults with MCI: significant improvements in multiple memory and cognitive measures versus placebo.
Pragmatic 12‑week randomized trial comparing naturopathic care (includes Ashwagandha 300 mg twice daily plus multivitamin, counseling, lifestyle) to psychotherapy in employees with moderate anxiety: naturopathic package produced larger BAI reductions and greater QoL improvements.
Pragmatic 12‑week randomized trial comparing naturopathic care (includes Ashwagandha 300 mg twice daily plus multivitamin, counseling, lifestyle) to psychotherapy in employees with moderate anxiety: naturopathic package produced larger BAI reductions and greater QoL improvements.
Pragmatic 12‑week randomized trial comparing naturopathic care (includes Ashwagandha 300 mg twice daily plus multivitamin, counseling, lifestyle) to psychotherapy in employees with moderate anxiety: naturopathic package produced larger BAI reductions and greater QoL improvements.
12‑week randomized double‑blind adjunctive trial of standardized Withania somnifera extract (1,000 mg) in patients with schizophrenia: secondary analysis found medium effect size improvements in depression and anxiety symptoms compared with placebo.
12‑week randomized double‑blind adjunctive trial of standardized Withania somnifera extract (1,000 mg) in patients with schizophrenia: secondary analysis found medium effect size improvements in depression and anxiety symptoms compared with placebo.
Adding Ashwagandha to SSRI treatment reduced OCD symptom scores more than placebo over 6 weeks with no adverse events reported.
Ashwagandha added to SSRI reduced anxiety (HAM-A) scores more than placebo over 6 weeks with no adverse effects reported.
A polyherbal (includes Ashwagandha) reduced illness duration, several symptom severities, and IL-6 versus placebo in hospitalized moderate COVID-19 patients; attribution to Ashwagandha alone is unclear.
A polyherbal (includes Ashwagandha) reduced illness duration, several symptom severities, and IL-6 versus placebo in hospitalized moderate COVID-19 patients; attribution to Ashwagandha alone is unclear.
Adjunctive ashwagandha reduced negative, general, and total PANSS symptoms and perceived stress versus placebo; inflammatory markers changed non-significantly.
Adjunctive ashwagandha reduced negative, general, and total PANSS symptoms and perceived stress versus placebo; inflammatory markers changed non-significantly.
Adjunctive standardized Withania somnifera extract (500 mg/day) for 8 weeks in euthymic bipolar patients improved specific cognitive tasks versus placebo with minor adverse events.
Adjunctive standardized Withania somnifera extract (500 mg/day) for 8 weeks in euthymic bipolar patients improved specific cognitive tasks versus placebo with minor adverse events.
Adjunctive standardized Withania somnifera extract (500 mg/day) for 8 weeks in euthymic bipolar patients improved specific cognitive tasks versus placebo with minor adverse events.
A 14-day randomized double-blind trial of a proprietary WS+AE blend showed reduced constipation symptoms, improved QoL and sleep, reduced stress, and favorable biomarker changes at the higher dose.
A 14-day randomized double-blind trial of a proprietary WS+AE blend showed reduced constipation symptoms, improved QoL and sleep, reduced stress, and favorable biomarker changes at the higher dose.
A 14-day randomized double-blind trial of a proprietary WS+AE blend showed reduced constipation symptoms, improved QoL and sleep, reduced stress, and favorable biomarker changes at the higher dose.
An 8-week randomized double-blind placebo-controlled pilot of high-concentration Ashwagandha extract (KSM-66) plus counseling improved female sexual function and reduced sexual distress vs placebo with good tolerability.
An 8-week randomized double-blind placebo-controlled pilot of high-concentration Ashwagandha extract (KSM-66) plus counseling improved female sexual function and reduced sexual distress vs placebo with good tolerability.
An 8-week randomized double-blind placebo-controlled pilot of high-concentration Ashwagandha extract (KSM-66) plus counseling improved female sexual function and reduced sexual distress vs placebo with good tolerability.
Triple-blind RCT in 100 infertile men comparing Ashwagandha (5 g/day) vs pentoxifylline for 90 days; sperm count, progressive motility and morphology improved from baseline with Ashwagandha; no major adverse events and no significant differences between groups after treatment.
Interim analysis (first 160 completers, 8 weeks) of a randomized open-label trial in HCWs showed Ashwagandha (250 mg twice daily) was non-inferior to weekly HCQ for preventing symptomatic RT-PCR-confirmed COVID-19 and had fewer mild adverse events.
Interim analysis (first 160 completers, 8 weeks) of a randomized open-label trial in HCWs showed Ashwagandha (250 mg twice daily) was non-inferior to weekly HCQ for preventing symptomatic RT-PCR-confirmed COVID-19 and had fewer mild adverse events.
Randomized double-blind placebo-controlled add-on trial in 120 newly diagnosed sputum-positive TB patients for 12 weeks found that Ashwagandha with DOTS improved sputum conversion rates, increased CD4/CD8 counts, and produced greater gains in quality of life versus placebo.
Randomized double-blind placebo-controlled add-on trial in 120 newly diagnosed sputum-positive TB patients for 12 weeks found that Ashwagandha with DOTS improved sputum conversion rates, increased CD4/CD8 counts, and produced greater gains in quality of life versus placebo.
Randomized double-blind placebo-controlled add-on trial in 120 newly diagnosed sputum-positive TB patients for 12 weeks found that Ashwagandha with DOTS improved sputum conversion rates, increased CD4/CD8 counts, and produced greater gains in quality of life versus placebo.