Supplement

Ashwagandha

Ashwagandha is a root herb from Ayurvedic tradition, classed as an adaptogen because it appears to steer the body's stress-hormone system and lower cortisol. People mostly look at it for stress, where the evidence is strong, and across five studies with about 540 people, anxiety symptoms improved. The anxiety findings are moderate in strength, though, and results for other uses, like blood sugar, rest on small, limited studies.

Sources: PMID 39083548; PMID 19718255

Updated 30 September 2026
How we grade
49 studies cited

Best evidence: Grade B
Conditions studied: 36
Outcomes: 318
Graded outcomes: 08235

Evidence by condition

Strong
Moderate
Limited
Very limited

36 conditions

Stress

Stress: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People
	Anxiety Symptoms Moderate Improvement	Improves (the measure goes down)	Moderate effect	5 studies	540 people
Studies that measured anxiety symptoms A double-blind, placebo-controlled evaluation of the anxiolytic efficacy ff an ethanolic extract of withania somniferaIndian J Psychiatry · PMID 21407960 Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974PLoS One · PMID 19718255 Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysis.Hum Psychopharmacol · PMID 39083548 Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysisPLoS One · PMID 34559859 Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled StudyCureus · PMID 31728244
	Blood glucose Small Improvement	Improves (the measure goes down)	Small effect	1 study	130 people
Studies that measured blood glucose Hypoglycemic, diuretic and hypocholesterolemic effect of winter cherry (Withania somnifera, Dunal) rootIndian J Exp Biol · PMID 11116534
	Stress Signs and Symptoms	Improves (the measure goes down)		3 studies	482 people
Studies that measured stress signs and symptoms Does Ashwagandha supplementation have a beneficial effect on the management of anxiety and stress? A systematic review and meta-analysis of randomized controlled trialsPhytother Res · PMID 36017529 A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adultsIndian J Psychol Med · PMID 23439798 Adaptogenic and Anxiolytic Effects of Ashwagandha Root Extract in Healthy Adults: A Double-blind, Randomized, Placebo-controlled Clinical StudyCureus · PMID 32021735
	Condition-Related Fatigue	Improves (the measure goes down)		1 study	130 people
Studies that measured condition-related fatigue A Randomized, Double-Blind, Placebo-Controlled, Crossover Study Examining the Hormonal and Vitality Effects of Ashwagandha ( Withania somnifera) in Aging, Overweight MalesAm J Mens Health · PMID 30854916
	Cortisol	Improves (the measure goes down)		1 study	254 people
Studies that measured cortisol An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract: A randomized, double-blind, placebo-controlled studyMedicine · PMID 31517876
	Heart Rate	Improves (the measure goes down)		1 study	182 people
	High-density lipoprotein (HDL)	Improves (the measure goes up)		1 study	130 people
	Insomnia Signs and Symptoms	Improves (the measure goes down)		1 study	130 people
	Blood Pressure	Improves (the measure goes down)			182 people
	Body Temperature	Improves (the measure goes up)			52 people
	C-Reactive Protein (CRP)	Improves (the measure goes down)			130 people
	Depression Symptoms	Improves (the measure goes down)			64 people
	Dry Mouth Symptoms	Improves (the measure goes down)			130 people
	Irritability	Improves (the measure goes down)			130 people
	Low-density lipoprotein (LDL)	Improves (the measure goes down)			130 people
	Serum DHEA	Improves (the measure goes up)			130 people
	Sleep Quality	Improves (the measure goes up)			60 people
	Social Functioning	Improves (the measure goes up)			64 people
	Subjective Well-Being	Improves (the measure goes up)			52 people
	Total cholesterol	Improves (the measure goes down)			130 people
	Triglycerides	Improves (the measure goes down)			130 people
	vLDL-C	Improves (the measure goes down)			130 people
	Weight	Improves (the measure goes down)			52 people
	Fatigue Symptoms	Changes; see studies			130 people

Anxiety Disorders Other

Anxiety Disorders Other: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People
	Anxiety Symptoms Moderate Improvement	Improves (the measure goes down)	Moderate effect	5 studies	540 people
Studies that measured anxiety symptoms A double-blind, placebo-controlled evaluation of the anxiolytic efficacy ff an ethanolic extract of withania somniferaIndian J Psychiatry · PMID 21407960 Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974PLoS One · PMID 19718255 Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysis.Hum Psychopharmacol · PMID 39083548 Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysisPLoS One · PMID 34559859 Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled StudyCureus · PMID 31728244
	Stress Signs and Symptoms	Improves (the measure goes down)		3 studies	482 people
Studies that measured stress signs and symptoms Does Ashwagandha supplementation have a beneficial effect on the management of anxiety and stress? A systematic review and meta-analysis of randomized controlled trialsPhytother Res · PMID 36017529 A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adultsIndian J Psychol Med · PMID 23439798 Adaptogenic and Anxiolytic Effects of Ashwagandha Root Extract in Healthy Adults: A Double-blind, Randomized, Placebo-controlled Clinical StudyCureus · PMID 32021735
	Condition-Related Fatigue	Improves (the measure goes down)		1 study	75 people
Studies that measured condition-related fatigue A Randomized, Double-Blind, Placebo-Controlled, Crossover Study Examining the Hormonal and Vitality Effects of Ashwagandha ( Withania somnifera) in Aging, Overweight MalesAm J Mens Health · PMID 30854916
	Depression Symptoms	Improves (the measure goes down)			21 people
	Motivation	Improves (the measure goes up)			75 people
	Sleep Duration	Improves (the measure goes up)			95 people
	Sleep Efficiency	Improves (the measure goes up)			95 people
	Sleep Latency	Improves (the measure goes down)			95 people
	Sleep Quality	Improves (the measure goes up)			95 people
	Weight	Improves (the measure goes down)			75 people

Anxiety Disorders (Other)

Anxiety Symptoms: improves
Stress Signs and Symptoms: changes; see studies
Depression Symptoms: changes; see studies

Anxiety Disorders (Other): outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People
	Anxiety Symptoms Moderate Improvement	Improves (the measure goes down)	Moderate effect	5 studies	540 people
Studies that measured anxiety symptoms A double-blind, placebo-controlled evaluation of the anxiolytic efficacy ff an ethanolic extract of withania somniferaIndian J Psychiatry · PMID 21407960 Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974PLoS One · PMID 19718255 Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysis.Hum Psychopharmacol · PMID 39083548 Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysisPLoS One · PMID 34559859 Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled StudyCureus · PMID 31728244
	Stress Signs and Symptoms	Changes; see studies		3 studies	482 people
Studies that measured stress signs and symptoms Does Ashwagandha supplementation have a beneficial effect on the management of anxiety and stress? A systematic review and meta-analysis of randomized controlled trialsPhytother Res · PMID 36017529 A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adultsIndian J Psychol Med · PMID 23439798 Adaptogenic and Anxiolytic Effects of Ashwagandha Root Extract in Healthy Adults: A Double-blind, Randomized, Placebo-controlled Clinical StudyCureus · PMID 32021735
	Depression Symptoms	Changes; see studies			21 people
	Fatigue Symptoms	Changes; see studies			75 people
	Motivation	Improves (the measure goes up)			75 people
	Sleep Duration	Improves (the measure goes up)			95 people
	Sleep Efficiency	Improves (the measure goes up)			95 people
	Sleep Latency	Changes; see studies			95 people
	Sleep Quality	Improves (the measure goes up)			95 people
	Weight	Changes; see studies			75 people

Muscle Size Strength

Aerobic Exercise Metrics: improves
Testosterone: improves
Oxygen Uptake: improves

Muscle Size Strength: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People
	Aerobic Exercise Metrics Moderate Improvement	Improves (the measure goes up)	Moderate effect	1 study	226 people
Studies that measured aerobic exercise metrics Effects of Ashwagandha ( Withania somnifera) on Physical Performance: Systematic Review and Bayesian Meta-AnalysisJ Funct Morphol Kinesiol · PMID 33670194
	Testosterone	Improves (the measure goes up)		5 studies	57 people
Studies that measured testosterone Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trialJ Int Soc Sports Nutr · PMID 26609282 Efficacy of Withania somnifera on seminal plasma metabolites of infertile males: a proton NMR study at 800 MHzJ Ethnopharmacol · PMID 23796876 Withania somnifera Improves Semen Quality in Stress-Related Male FertilityEvid Based Complement Alternat Med · PMID 19789214 Withania somnifera improves semen quality by regulating reproductive hormone levels and oxidative stress in seminal plasma of infertile malesFertil Steril · PMID 19501822 Clinical Evaluation of the Spermatogenic Activity of the Root Extract of Ashwagandha (Withania somnifera) in Oligospermic Males: A Pilot StudyEvid Based Complement Alternat Med · PMID 24371462
	Oxygen Uptake	Improves (the measure goes up)		2 studies	40 people
Studies that measured oxygen uptake Effects of Withania somnifera (Ashwagandha) and Terminalia arjuna (Arjuna) on physical performance and cardiorespiratory endurance in healthy young adultsInt J Ayurveda Res · PMID 21170205 Effects of eight-week supplementation of Ashwagandha on cardiorespiratory endurance in elite Indian cyclistsJ Ayurveda Integr Med · PMID 23326093
	High-density lipoprotein (HDL)	Improves (the measure goes up)		1 study	57 people
Studies that measured high-density lipoprotein (hdl) Effects of Withania somnifera in patients of schizophrenia: A randomized, double blind, placebo controlled pilot trial studyIndian J Pharmacol · PMID 24014929
	Red Blood Cell Count	Improves (the measure goes up)		1 study	57 people
Studies that measured red blood cell count Effects of an Aqueous Extract of Withania somnifera on Strength Training Adaptations and Recovery: The STAR TrialNutrients · PMID 30463324
	White Blood Cell Count	Improves (the measure goes up)		1 study	57 people
	Anaerobic Capacity	Improves (the measure goes up)			40 people
	Blood Pressure	Improves (the measure goes down)			40 people
	Body Fat	Improves (the measure goes down)			114 people
	Exercise Capacity	Improves (the measure goes up)			40 people
	Hematocrit	Improves (the measure goes up)			40 people
	Hemoglobin	Improves (the measure goes up)			40 people
	Kidney Function	Improves (the measure goes up)			40 people
	Liver Enzymes	Changes; see studies			57 people
	Low-density lipoprotein (LDL)	Improves (the measure goes down)			57 people
	Muscle Damage	Changes; see studies			57 people
	Muscle Mass	Improves (the measure goes up)			57 people
	Muscle Soreness	Improves (the measure goes down)			40 people
	Power Output	Improves (the measure goes up)			154 people
	Rating of Perceived Exertion	Improves (the measure goes up)			17 people
	Serum Albumin	Improves (the measure goes up)			40 people
	Serum Platelets	Improves (the measure goes up)			17 people
	Strength	Improves (the measure goes up)			198 people
	Subjective Well-Being	Improves (the measure goes up)			40 people
	Total cholesterol	Improves (the measure goes down)			57 people
	Triglycerides	Improves (the measure goes down)			57 people
	Urea	Improves (the measure goes up)			40 people
	vLDL-C	Improves (the measure goes down)			40 people
	Weight	Improves (the measure goes down)			57 people

General Athletic Performance

Aerobic Exercise Metrics: improves
Testosterone: improves
Oxygen Uptake: improves

General Athletic Performance: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People
	Aerobic Exercise Metrics Moderate Improvement	Improves (the measure goes up)	Moderate effect	1 study	85 people
Studies that measured aerobic exercise metrics Effects of Ashwagandha ( Withania somnifera) on Physical Performance: Systematic Review and Bayesian Meta-AnalysisJ Funct Morphol Kinesiol · PMID 33670194
	Testosterone	Improves (the measure goes up)		5 studies	57 people
Studies that measured testosterone Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trialJ Int Soc Sports Nutr · PMID 26609282 Efficacy of Withania somnifera on seminal plasma metabolites of infertile males: a proton NMR study at 800 MHzJ Ethnopharmacol · PMID 23796876 Withania somnifera Improves Semen Quality in Stress-Related Male FertilityEvid Based Complement Alternat Med · PMID 19789214 Withania somnifera improves semen quality by regulating reproductive hormone levels and oxidative stress in seminal plasma of infertile malesFertil Steril · PMID 19501822 Clinical Evaluation of the Spermatogenic Activity of the Root Extract of Ashwagandha (Withania somnifera) in Oligospermic Males: A Pilot StudyEvid Based Complement Alternat Med · PMID 24371462
	Oxygen Uptake	Improves (the measure goes up)		2 studies	85 people
Studies that measured oxygen uptake Effects of Withania somnifera (Ashwagandha) and Terminalia arjuna (Arjuna) on physical performance and cardiorespiratory endurance in healthy young adultsInt J Ayurveda Res · PMID 21170205 Effects of eight-week supplementation of Ashwagandha on cardiorespiratory endurance in elite Indian cyclistsJ Ayurveda Integr Med · PMID 23326093
	Blood glucose	Improves (the measure goes down)		1 study	57 people
Studies that measured blood glucose Hypoglycemic, diuretic and hypocholesterolemic effect of winter cherry (Withania somnifera, Dunal) rootIndian J Exp Biol · PMID 11116534
	High-density lipoprotein (HDL)	Improves (the measure goes up)		1 study	57 people
Studies that measured high-density lipoprotein (hdl) Effects of Withania somnifera in patients of schizophrenia: A randomized, double blind, placebo controlled pilot trial studyIndian J Pharmacol · PMID 24014929
	Red Blood Cell Count	Improves (the measure goes up)		1 study	57 people
	White Blood Cell Count	Improves (the measure goes up)		1 study	57 people
	Anaerobic Capacity	Improves (the measure goes up)			40 people
	Blood Pressure	Improves (the measure goes down)			40 people
	Body Fat	Improves (the measure goes down)			114 people
	Exercise Capacity	Improves (the measure goes up)			40 people
	Fat Oxidation	Improves (the measure goes up)			45 people
	Hematocrit	Improves (the measure goes up)			40 people
	Hemoglobin	Improves (the measure goes up)			40 people
	Kidney Function	Improves (the measure goes up)			40 people
	Liver Enzymes	Changes; see studies			57 people
	Low-density lipoprotein (LDL)	Improves (the measure goes down)			57 people
	Muscle Damage	Changes; see studies			57 people
	Muscle Mass	Improves (the measure goes up)			57 people
	Muscle Soreness	Improves (the measure goes down)			40 people
	Power Output	Improves (the measure goes up)			154 people
	Rating of Perceived Exertion	Improves (the measure goes up)			17 people
	Serum Albumin	Improves (the measure goes up)			40 people
	Serum Platelets	Improves (the measure goes up)			17 people
	Subjective Well-Being	Improves (the measure goes up)			40 people
	Total cholesterol	Improves (the measure goes down)			57 people
	Triglycerides	Improves (the measure goes down)			57 people
	Urea	Improves (the measure goes up)			40 people
	vLDL-C	Improves (the measure goes down)			40 people
	Weight	Improves (the measure goes down)			57 people

Aerobic Exercise Performance

Aerobic Exercise Metrics: improves
Oxygen Uptake: improves
Blood glucose: improves

Aerobic Exercise Performance: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People
	Aerobic Exercise Metrics Moderate Improvement	Improves (the measure goes up)	Moderate effect	1 study	226 people
Studies that measured aerobic exercise metrics Effects of Ashwagandha ( Withania somnifera) on Physical Performance: Systematic Review and Bayesian Meta-AnalysisJ Funct Morphol Kinesiol · PMID 33670194
	Oxygen Uptake	Improves (the measure goes up)		2 studies	85 people
Studies that measured oxygen uptake Effects of Withania somnifera (Ashwagandha) and Terminalia arjuna (Arjuna) on physical performance and cardiorespiratory endurance in healthy young adultsInt J Ayurveda Res · PMID 21170205 Effects of eight-week supplementation of Ashwagandha on cardiorespiratory endurance in elite Indian cyclistsJ Ayurveda Integr Med · PMID 23326093
	Blood glucose	Improves (the measure goes down)		1 study	40 people
Studies that measured blood glucose Hypoglycemic, diuretic and hypocholesterolemic effect of winter cherry (Withania somnifera, Dunal) rootIndian J Exp Biol · PMID 11116534
	Red Blood Cell Count	Improves (the measure goes up)		1 study	40 people
Studies that measured red blood cell count Effects of an Aqueous Extract of Withania somnifera on Strength Training Adaptations and Recovery: The STAR TrialNutrients · PMID 30463324
	White Blood Cell Count	Improves (the measure goes up)		1 study	40 people
Studies that measured white blood cell count Exploratory study to evaluate tolerability, safety, and activity of Ashwagandha (Withania somnifera) in healthy volunteersJ Ayurveda Integr Med · PMID 23125505
	Anaerobic Capacity	Improves (the measure goes up)			40 people
	Body Fat	Improves (the measure goes down)			40 people
	Exercise Capacity	Improves (the measure goes up)			40 people
	Fat Oxidation	Improves (the measure goes up)			45 people
	Hematocrit	Improves (the measure goes up)			40 people
	Hemoglobin	Improves (the measure goes up)			40 people
	Muscle Mass	Improves (the measure goes up)			40 people
	Muscle Soreness	Improves (the measure goes down)			40 people
	Power Output	Improves (the measure goes up)			80 people
	Strength	Improves (the measure goes up)			198 people
	Urea	Improves (the measure goes up)			40 people
	vLDL-C	Improves (the measure goes down)			40 people
	Weight	Improves (the measure goes down)			40 people

Muscle Size & Strength

Aerobic Exercise Metrics: improves
Testosterone: improves
Oxygen Uptake: improves

Muscle Size & Strength: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People
	Aerobic Exercise Metrics Moderate Improvement	Improves (the measure goes up)	Moderate effect	1 study	226 people
Studies that measured aerobic exercise metrics Effects of Ashwagandha ( Withania somnifera) on Physical Performance: Systematic Review and Bayesian Meta-AnalysisJ Funct Morphol Kinesiol · PMID 33670194
	Testosterone	Improves (the measure goes up)		5 studies	57 people
Studies that measured testosterone Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trialJ Int Soc Sports Nutr · PMID 26609282 Efficacy of Withania somnifera on seminal plasma metabolites of infertile males: a proton NMR study at 800 MHzJ Ethnopharmacol · PMID 23796876 Withania somnifera Improves Semen Quality in Stress-Related Male FertilityEvid Based Complement Alternat Med · PMID 19789214 Withania somnifera improves semen quality by regulating reproductive hormone levels and oxidative stress in seminal plasma of infertile malesFertil Steril · PMID 19501822 Clinical Evaluation of the Spermatogenic Activity of the Root Extract of Ashwagandha (Withania somnifera) in Oligospermic Males: A Pilot StudyEvid Based Complement Alternat Med · PMID 24371462
	Oxygen Uptake	Improves (the measure goes up)		2 studies	40 people
Studies that measured oxygen uptake Effects of Withania somnifera (Ashwagandha) and Terminalia arjuna (Arjuna) on physical performance and cardiorespiratory endurance in healthy young adultsInt J Ayurveda Res · PMID 21170205 Effects of eight-week supplementation of Ashwagandha on cardiorespiratory endurance in elite Indian cyclistsJ Ayurveda Integr Med · PMID 23326093
	High-density lipoprotein (HDL)	Improves (the measure goes up)		1 study	57 people
Studies that measured high-density lipoprotein (hdl) Effects of Withania somnifera in patients of schizophrenia: A randomized, double blind, placebo controlled pilot trial studyIndian J Pharmacol · PMID 24014929
	Red Blood Cell Count	Improves (the measure goes up)		1 study	57 people
Studies that measured red blood cell count Effects of an Aqueous Extract of Withania somnifera on Strength Training Adaptations and Recovery: The STAR TrialNutrients · PMID 30463324
	White Blood Cell Count	Improves (the measure goes up)		1 study	57 people
	Anaerobic Capacity	Improves (the measure goes up)			40 people
	Blood Pressure	Changes; see studies			40 people
	Body Fat	Changes; see studies			114 people
	Exercise Capacity	Improves (the measure goes up)			40 people
	Hematocrit	Improves (the measure goes up)			40 people
	Hemoglobin	Improves (the measure goes up)			40 people
	Kidney Function	Improves (the measure goes up)			40 people
	Liver Enzymes	Changes; see studies			57 people
	Low-density lipoprotein (LDL)	Changes; see studies			57 people
	Muscle Damage	Changes; see studies			57 people
	Muscle Mass	Improves (the measure goes up)			57 people
	Muscle Soreness	Changes; see studies			40 people
	Power Output	Improves (the measure goes up)			154 people
	Rating of Perceived Exertion	Improves (the measure goes up)			17 people
	Serum Albumin	Improves (the measure goes up)			40 people
	Serum Platelets	Improves (the measure goes up)			17 people
	Strength	Improves (the measure goes up)			198 people
	Subjective Well-Being	Improves (the measure goes up)			40 people
	Total cholesterol	Changes; see studies			57 people
	Triglycerides	Changes; see studies			57 people
	Urea	Improves (the measure goes up)			40 people
	vLDL-C	Changes; see studies			40 people
	Weight	Changes; see studies			57 people

Insomnia

Alertness: improves
Anxiety Symptoms: improves
Quality of Life: improves

Insomnia: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People
	Alertness Small Improvement	Improves (the measure goes up)	Small effect		170 people
	Anxiety Symptoms	Improves (the measure goes down)		5 studies	189 people
Studies that measured anxiety symptoms A double-blind, placebo-controlled evaluation of the anxiolytic efficacy ff an ethanolic extract of withania somniferaIndian J Psychiatry · PMID 21407960 Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974PLoS One · PMID 19718255 Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysis.Hum Psychopharmacol · PMID 39083548 Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysisPLoS One · PMID 34559859 Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled StudyCureus · PMID 31728244
	Quality of Life	Improves (the measure goes up)		1 study	189 people
Studies that measured quality of life Efficacy of Ashwagandha (Withania somnifera [L.] Dunal) in improving cardiorespiratory endurance in healthy athletic adultsAyu · PMID 26730141
	Sleep Duration	Improves (the measure goes up)			281 people
	Sleep Efficiency	Improves (the measure goes up)			281 people
	Sleep Latency	Improves (the measure goes down)			281 people
	Sleep Quality	Improves (the measure goes up)			1,764 people

Low Testosterone

Anxiety Symptoms: improves
Testosterone: improves
Cortisol: improves

Low Testosterone: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People
	Anxiety Symptoms Moderate Improvement	Improves (the measure goes down)	Moderate effect	5 studies	60 people
Studies that measured anxiety symptoms A double-blind, placebo-controlled evaluation of the anxiolytic efficacy ff an ethanolic extract of withania somniferaIndian J Psychiatry · PMID 21407960 Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974PLoS One · PMID 19718255 Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysis.Hum Psychopharmacol · PMID 39083548 Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysisPLoS One · PMID 34559859 Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled StudyCureus · PMID 31728244
	Testosterone	Improves (the measure goes up)		5 studies	135 people
Studies that measured testosterone Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trialJ Int Soc Sports Nutr · PMID 26609282 Efficacy of Withania somnifera on seminal plasma metabolites of infertile males: a proton NMR study at 800 MHzJ Ethnopharmacol · PMID 23796876 Withania somnifera Improves Semen Quality in Stress-Related Male FertilityEvid Based Complement Alternat Med · PMID 19789214 Withania somnifera improves semen quality by regulating reproductive hormone levels and oxidative stress in seminal plasma of infertile malesFertil Steril · PMID 19501822 Clinical Evaluation of the Spermatogenic Activity of the Root Extract of Ashwagandha (Withania somnifera) in Oligospermic Males: A Pilot StudyEvid Based Complement Alternat Med · PMID 24371462
	Cortisol	Improves (the measure goes down)		1 study	60 people
Studies that measured cortisol An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract: A randomized, double-blind, placebo-controlled studyMedicine · PMID 31517876
	Sperm Quality	Improves (the measure goes up)		1 study	75 people
Studies that measured sperm quality Comparative evaluation of the effects of Withania somnifera with pentoxifylline on the sperm parameters in idiopathic male infertility: A triple-blind randomised clinical trialAndrologia · PMID 29770466
	Follicle-Stimulating Hormone	Improves (the measure goes up)			75 people
	Luteinizing Hormone	Improves (the measure goes up)			75 people

Bipolar Disorder

Anxiety Symptoms: improves
Bipolar Disorder Symptoms: improves
Attention: improves

Bipolar Disorder: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People
	Anxiety Symptoms Moderate Improvement	Improves (the measure goes down)	Moderate effect	5 studies	60 people
Studies that measured anxiety symptoms A double-blind, placebo-controlled evaluation of the anxiolytic efficacy ff an ethanolic extract of withania somniferaIndian J Psychiatry · PMID 21407960 Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974PLoS One · PMID 19718255 Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysis.Hum Psychopharmacol · PMID 39083548 Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysisPLoS One · PMID 34559859 Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled StudyCureus · PMID 31728244
	Bipolar Disorder Symptoms	Improves (the measure goes down)		1 study	60 people
Studies that measured bipolar disorder symptoms Randomized placebo-controlled adjunctive study of an extract of withania somnifera for cognitive dysfunction in bipolar disorderJ Clin Psychiatry · PMID 24330893
	Attention	Improves (the measure goes up)			60 people
	Depression Symptoms	Improves (the measure goes down)			60 people
	Executive Function	Improves (the measure goes up)			60 people
	Memory	Improves (the measure goes up)			60 people
	Processing Accuracy	Improves (the measure goes up)			60 people
	Processing Speed	Improves (the measure goes up)			60 people

Generalized Anxiety Disorder (GAD)

Anxiety Symptoms: improves
Insomnia Signs and Symptoms: improves
Memory: improves

Generalized Anxiety Disorder (GAD): outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People
	Anxiety Symptoms Moderate Improvement	Improves (the measure goes down)	Moderate effect	5 studies	86 people
Studies that measured anxiety symptoms A double-blind, placebo-controlled evaluation of the anxiolytic efficacy ff an ethanolic extract of withania somniferaIndian J Psychiatry · PMID 21407960 Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974PLoS One · PMID 19718255 Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysis.Hum Psychopharmacol · PMID 39083548 Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysisPLoS One · PMID 34559859 Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled StudyCureus · PMID 31728244
	Insomnia Signs and Symptoms	Improves (the measure goes down)		1 study	86 people
Studies that measured insomnia signs and symptoms Effect of Withania somnifera (Ashwagandha) on the development of chemotherapy-induced fatigue and quality of life in breast cancer patientsIntegr Cancer Ther · PMID 23142798
	Memory	Improves (the measure goes up)			86 people
	Subjective Well-Being	Improves (the measure goes up)			86 people

Mood Improvement

Anxiety Symptoms: improves
Testosterone: improves
Cortisol: improves

Mood Improvement: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People
	Anxiety Symptoms Moderate Improvement	Improves (the measure goes down)	Moderate effect	5 studies	60 people
Studies that measured anxiety symptoms A double-blind, placebo-controlled evaluation of the anxiolytic efficacy ff an ethanolic extract of withania somniferaIndian J Psychiatry · PMID 21407960 Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974PLoS One · PMID 19718255 Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysis.Hum Psychopharmacol · PMID 39083548 Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysisPLoS One · PMID 34559859 Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled StudyCureus · PMID 31728244
	Testosterone	Improves (the measure goes up)		5 studies	60 people
Studies that measured testosterone Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trialJ Int Soc Sports Nutr · PMID 26609282 Efficacy of Withania somnifera on seminal plasma metabolites of infertile males: a proton NMR study at 800 MHzJ Ethnopharmacol · PMID 23796876 Withania somnifera Improves Semen Quality in Stress-Related Male FertilityEvid Based Complement Alternat Med · PMID 19789214 Withania somnifera improves semen quality by regulating reproductive hormone levels and oxidative stress in seminal plasma of infertile malesFertil Steril · PMID 19501822 Clinical Evaluation of the Spermatogenic Activity of the Root Extract of Ashwagandha (Withania somnifera) in Oligospermic Males: A Pilot StudyEvid Based Complement Alternat Med · PMID 24371462
	Cortisol	Improves (the measure goes down)		1 study	60 people
Studies that measured cortisol An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract: A randomized, double-blind, placebo-controlled studyMedicine · PMID 31517876

Running Performance

Oxygen Uptake: improves
Quality of Life: improves

Running Performance: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Oxygen Uptake Small Improvement	Improves (the measure goes up)	Small effect	2 studies	50 people
	Quality of Life	Improves (the measure goes up)		1 study	50 people

Infertility

Cortisol: improves
Testosterone: improves
Sperm Quality: improves

Infertility: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Cortisol Moderate Decrease	Improves (the measure goes down)	Moderate effect	1 study	60 people
Testosterone	Improves (the measure goes up)		5 studies	361 people
Sperm Quality	Improves (the measure goes up)		1 study	401 people
Follicle-Stimulating Hormone	Improves (the measure goes up)			135 people
Luteinizing Hormone	Improves (the measure goes up)			181 people
Seminal Motility	Improves (the measure goes up)			286 people
Sperm Count	Improves (the measure goes up)			206 people

Body Composition

Blood glucose: improves
Testosterone: improves
White Blood Cell Count: improves

Body Composition: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Blood glucose Small Improvement	Improves (the measure goes down)	Small effect	1 study	17 people
Testosterone	Improves (the measure goes up)		5 studies	57 people
White Blood Cell Count	Improves (the measure goes up)		1 study	17 people
Body Fat	Improves (the measure goes down)			74 people
Low-density lipoprotein (LDL)	Improves (the measure goes down)			17 people
Muscle Damage	Changes; see studies			57 people
Muscle Mass	Improves (the measure goes up)			17 people
Power Output	Improves (the measure goes up)			74 people
Weight	Improves (the measure goes down)			17 people

Schizophrenia

Blood glucose: improves
Stress Signs and Symptoms: improves
Heart Rate: improves

Schizophrenia: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Blood glucose Small Improvement	Improves (the measure goes down)	Small effect	1 study	25 people
Stress Signs and Symptoms	Improves (the measure goes down)		3 studies	68 people
Heart Rate	Improves (the measure goes down)		1 study	68 people
High-density lipoprotein (HDL)	Improves (the measure goes up)		1 study	25 people
Schizophrenia symptoms	Improves (the measure goes down)		1 study	68 people
Blood Pressure	Improves (the measure goes down)			68 people
C-Reactive Protein (CRP)	Improves (the measure goes down)			68 people
Interleukin 6	Improves (the measure goes down)			68 people
Triglycerides	Improves (the measure goes down)			25 people
Weight	Improves (the measure goes down)			68 people

High Cholesterol

Blood glucose: improves
Low-density lipoprotein (LDL): improves
Total cholesterol: improves

High Cholesterol: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Blood glucose Small Improvement	Improves (the measure goes down)	Small effect	1 study	12 people
Low-density lipoprotein (LDL)	Improves (the measure goes down)			12 people
Total cholesterol	Improves (the measure goes down)			12 people
Triglycerides	Improves (the measure goes down)			12 people

Type 2 Diabetes

Blood glucose: improves
Diuresis: improves
Low-density lipoprotein (LDL): improves

Type 2 Diabetes: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Blood glucose Small Improvement	Improves (the measure goes down)	Small effect	1 study	12 people
Diuresis	Improves (the measure goes up)			12 people
Low-density lipoprotein (LDL)	Improves (the measure goes down)			12 people
Total cholesterol	Improves (the measure goes down)			12 people
Triglycerides	Improves (the measure goes down)			12 people

Cycling Performance

Aerobic Exercise Metrics: improves
Oxygen Uptake: improves
Fat Oxidation: improves

Cycling Performance: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Aerobic Exercise Metrics Moderate Improvement	Improves (the measure goes up)	Moderate effect	1 study	45 people
Oxygen Uptake	Improves (the measure goes up)		2 studies	45 people
Fat Oxidation	Improves (the measure goes up)			45 people

Muscle Recovery

Aerobic Exercise Metrics: improves
Blood glucose: improves
Red Blood Cell Count: improves

Muscle Recovery: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Aerobic Exercise Metrics Moderate Improvement	Improves (the measure goes up)	Moderate effect	1 study	40 people
Blood glucose	Improves (the measure goes down)		1 study	40 people
Red Blood Cell Count	Improves (the measure goes up)		1 study	40 people
White Blood Cell Count	Improves (the measure goes up)		1 study	40 people
Body Fat	Improves (the measure goes down)			40 people
Exercise Capacity	Improves (the measure goes up)			40 people
Hematocrit	Improves (the measure goes up)			40 people
Hemoglobin	Improves (the measure goes up)			40 people
Kidney Function	Improves (the measure goes up)			40 people
Muscle Mass	Improves (the measure goes up)			40 people
Muscle Soreness	Improves (the measure goes down)			40 people
Power Output	Improves (the measure goes up)			40 people
Urea	Improves (the measure goes up)			40 people

General Cardiovascular Health

Anaerobic Capacity: improves
Oxygen Uptake: improves
Blood glucose: improves

General Cardiovascular Health: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Anaerobic Capacity Small Improvement	Improves (the measure goes up)	Small effect		40 people
Oxygen Uptake	Improves (the measure goes up)		2 studies	40 people
Blood glucose	Improves (the measure goes down)		1 study	17 people
High-density lipoprotein (HDL)	Improves (the measure goes up)		1 study	17 people
Red Blood Cell Count	Improves (the measure goes up)		1 study	17 people
White Blood Cell Count	Improves (the measure goes up)		1 study	17 people
Blood Pressure	Improves (the measure goes down)			40 people
Body Fat	Improves (the measure goes down)			17 people
Liver Enzymes	Changes; see studies			17 people
Low-density lipoprotein (LDL)	Improves (the measure goes down)			17 people
Muscle Mass	Improves (the measure goes up)			17 people
Rating of Perceived Exertion	Improves (the measure goes up)			17 people
Serum Platelets	Improves (the measure goes up)			17 people
Total cholesterol	Improves (the measure goes down)			17 people
Triglycerides	Improves (the measure goes down)			17 people
Weight	Improves (the measure goes down)			17 people

Cognitive Improvement

Alertness: improves
Reaction Time: improves
Working Memory: improves

Cognitive Improvement: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Alertness Small Improvement	Improves (the measure goes up)	Small effect		20 people
Reaction Time	Improves (the measure goes up)		1 study	20 people
Working Memory	Improves (the measure goes up)		1 study	50 people
Attention	Improves (the measure goes up)			50 people
Cognition	Improves (the measure goes up)			20 people
Executive Function	Improves (the measure goes up)			70 people
Memory	Improves (the measure goes up)			50 people
Motor Control	Improves (the measure goes up)			20 people
Processing Accuracy	Improves (the measure goes up)			20 people
Processing Speed	Improves (the measure goes up)			20 people
Spatial Processing	Improves (the measure goes up)			50 people

Metabolic Health

Anti-Oxidant Enzyme Profile: improves
Blood glucose: improves
High-density lipoprotein (HDL): improves

Metabolic Health: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Anti-Oxidant Enzyme Profile Small Increase	Improves (the measure goes up)	Small effect		30 people
Blood glucose	Improves (the measure goes down)		1 study	17 people
High-density lipoprotein (HDL)	Improves (the measure goes up)		1 study	17 people
Oxidative Stress Biomarkers	Improves (the measure goes down)		1 study	30 people
White Blood Cell Count	Improves (the measure goes up)		1 study	17 people
Body Fat	Improves (the measure goes down)			17 people
Liver Enzymes	Changes; see studies			17 people
Low-density lipoprotein (LDL)	Improves (the measure goes down)			17 people
Muscle Mass	Improves (the measure goes up)			17 people
Rating of Perceived Exertion	Improves (the measure goes up)			17 people
Total cholesterol	Improves (the measure goes down)			17 people
Triglycerides	Improves (the measure goes down)			17 people
Weight	Improves (the measure goes down)			17 people

Osteoarthritis (OA)

Osteoarthritis Symptoms: improves
Pain: improves

Osteoarthritis (OA): outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Osteoarthritis Symptoms Moderate Improvement	Improves (the measure goes down)	Moderate effect		60 people
	Pain	Improves (the measure goes down)		1 study	60 people

Hypothyroidism

Serum T3: improves
Thyroid-Stimulating Hormone: improves
Serum T4: improves

Hypothyroidism: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Serum T3 Moderate Increase	Improves (the measure goes up)	Moderate effect		50 people
Thyroid-Stimulating Hormone	Improves (the measure goes up)		1 study	50 people
Serum T4	Improves (the measure goes up)			50 people

Immune Health

Immunity: improves
Natural Killer Cell Activity: improves

Immune Health: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Immunity Small Improvement	Improves (the measure goes up)	Small effect		5 people
	Natural Killer Cell Activity	Improves (the measure goes up)		1 study	5 people

Oligospermia

Luteinizing Hormone: improves
Testosterone: improves
Sperm Quality: improves

Oligospermia: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Luteinizing Hormone Small Increase	Improves (the measure goes up)	Small effect		46 people
Testosterone	Improves (the measure goes up)		5 studies	46 people
Sperm Quality	Improves (the measure goes up)		1 study	46 people
Seminal Motility	Improves (the measure goes up)			46 people
Sperm Count	Improves (the measure goes up)			46 people

Joint Pain

Osteoarthritis Symptoms: improves
Pain: improves

Joint Pain: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Osteoarthritis Symptoms Moderate Improvement	Improves (the measure goes down)	Moderate effect		60 people
	Pain	Improves (the measure goes down)		1 study	60 people

Chronic Nonspecific Knee Pain

Osteoarthritis Symptoms: improves
Pain: improves

Chronic Nonspecific Knee Pain: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Osteoarthritis Symptoms Moderate Improvement	Improves (the measure goes down)	Moderate effect		60 people
	Pain	Improves (the measure goes down)		1 study	60 people

Chemotherapy Side Effects

Fatigue Symptoms: improves
Condition-Related Fatigue
Insomnia Signs and Symptoms: improves

Chemotherapy Side Effects: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Fatigue Symptoms Small Improvement	Improves (the measure goes down)	Small effect		100 people
Condition-Related Fatigue No effect		NoneNo effect	1 study	100 people
Insomnia Signs and Symptoms	Improves (the measure goes down)		1 study	100 people
Pain	Improves (the measure goes down)		1 study	100 people
Social Functioning	Improves (the measure goes up)			100 people
Subjective Well-Being	Improves (the measure goes up)			100 people

Male Sexual Dysfunction

Erections
Testosterone: improves
Sperm Quality: improves

Male Sexual Dysfunction: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Erections No effect		NoneNo effect	1 study	86 people
Testosterone	Improves (the measure goes up)		5 studies	46 people
Sperm Quality	Improves (the measure goes up)		1 study	46 people
Luteinizing Hormone	Improves (the measure goes up)			46 people
Seminal Motility	Improves (the measure goes up)			46 people
Sperm Count	Improves (the measure goes up)			46 people

Obesity

Condition-Related Fatigue
Testosterone: improves
Cortisol: improves

Obesity: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Condition-Related Fatigue No effect		NoneNo effect	1 study	57 people
Testosterone	Improves (the measure goes up)		5 studies	57 people
Cortisol	Improves (the measure goes down)		1 study	57 people
Estrogen	Changes; see studies			57 people
Serum DHEA	Improves (the measure goes up)			57 people
Fatigue Symptoms	Changes; see studies			57 people

Overweight

Condition-Related Fatigue
Testosterone: improves
Cortisol: improves

Overweight: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Condition-Related Fatigue No effect		NoneNo effect	1 study	57 people
Testosterone	Improves (the measure goes up)		5 studies	57 people
Cortisol	Improves (the measure goes down)		1 study	57 people
Estrogen	Changes; see studies			57 people
Serum DHEA	Improves (the measure goes up)			57 people
Fatigue Symptoms	Changes; see studies			57 people

Weight Loss & Maintenance

Blood Pressure
Stress Signs and Symptoms: improves
Body Temperature: improves

Weight Loss & Maintenance: outcomes studied for Ashwagandha
Outcome	Effect	Size	Studies	People
Blood Pressure No effect		NoneNo effect		52 people
Stress Signs and Symptoms	Improves (the measure goes down)		3 studies	52 people
Body Temperature	Improves (the measure goes up)			52 people
Subjective Well-Being	Improves (the measure goes up)			52 people
Weight	Improves (the measure goes down)			52 people

Obsessive-Compulsive disorder (OCD)

OCD Symptoms: improves

Obsessive-Compulsive disorder (OCD): outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People	Studies list
	OCD Symptoms	Improves (the measure goes down)		1 study	30 people

Sexual Health

Sexual Function: improves

Sexual Health: outcomes studied for Ashwagandha
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Sexual Function	Improves (the measure goes up)		1 study	50 people

What the published studies found

6 automated readings

Automated reading of the published studies (Decosa evidence engine), for outcomes Dr. Grey has not graded yet. It is not a Dr. Grey grade and does not change one. How it is read

LDL cholesterol
The studies read are too weak to tell whether Ashwagandha changes LDL cholesterol. The evidence is very weak.
2 studies counted of 3 read: 1 trial (38 people in the trials).
1. Randomised trial, 2025; 38 people; young healthy men: no clear difference. no effect of training or supplementation on body composition and lipid profile Ashwagandha Does Not Enhance the Effect of High-Intensity Interval Training on Selected Energy Metabolism Parameters in Young Healthy MenPubMed 41156498
2. Non-randomised trial, 2000; 12 people: improves. Hypoglycemic, diuretic and hypocholesterolemic effect of winter cherry (Withania somnifera, Dunal) rootPubMed 11116534
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Cardiovascular events
Too few usable studies were found to tell whether Ashwagandha changes cardiovascular events. 3 studies were read and none could be counted.
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Memory
The best available review (2026, 20 studies, 1,249 people) found a moderate improvement in memory. All 8 studies read agree. The evidence is moderate.
8 studies counted of 11 read: 3 reviews and 5 trials (393 people in the trials).
1. Systematic review, 2026; 20 studies, 1,249 people: improves (the review the verdict rests on). Effects of Withania somnifera (L.) Dunal (Ashwagandha) on cognitive and physical function in adults: a systematic review and meta-analysisPubMed 42199854
2. Systematic review, 2026; 16 studies; individuals with bipolar disorder: improves. Withania somnifera (ashwagandha), insulin, and lurasidone each demonstrated cognitive benefits Improving Cognition in Bipolar Disorder: A Systematic Review of Current Pharmacological and Nutraceutical ApproachesPubMed 41843701
3. Systematic review, 2020; 5 studies; older adults with MCI, schizophrenia, schizoaffective, bipolar disorder: improves. improved performance on cognitive tasks, executive function, attention A systematic review of the clinical use of Withania somnifera (Ashwagandha) to ameliorate cognitive dysfunctionPubMed 31742775
4. Randomised trial, 2026; 120 people; adults with self-reported cognitive and energy problems: improves. Greater improvement (p < .05) from baseline scores Safety and Efficacy of Ashwagandha Root Extract on Cognition, Energy and Mood Problems in Adults: Prospective, Randomized, Placebo-Controlled StudyPubMed 39498904
5. Randomised trial, 2026; 85 people; children aged 6-12 with attention or memory concerns: improves. Improvements were also observed in delayed word recall A clinical assessment of the therapeutic effects of Ashwagandha root extract on cognitive performance, sleep, and fatigue in children aged 6-12 yearsPubMed 41889719
6. Crossover trial, 2022; 13 people; 13 healthy volunteers: improves. increased STT-determined working memory as demonstrated Effects of Acute Ashwagandha Ingestion on Cognitive FunctionPubMed 36231152
7. Randomised trial, 2021; 125 people; healthy stressed adults: improves. significantly improved recall memory, and the total error rate Efficacy and Safety of Ashwagandha Root Extract on Cognitive Functions in Healthy, Stressed Adults: A Randomized, Double-Blind, Placebo-Controlled StudyPubMed 34858513
8. Randomised trial, 2017; 50 people; adults with mild cognitive impairment: improves. significant improvements compared with the placebo group in both immediate and general memory Efficacy and Safety of Ashwagandha (Withania somnifera (L.) Dunal) Root Extract in Improving Memory and Cognitive FunctionsPubMed 28471731
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Muscle strength
The studies disagree. The best available review (2026, 3 studies, 161 people) did not settle it for muscle strength, while 8 of the 10 studies read found an improvement. The evidence is very weak.
10 studies counted of 11 read: 4 reviews and 6 trials (300 people in the trials).
1. Meta-analysis, 2026; 3 studies, 161 people; healthy adults undergoing resistance training: unclear: evidence too weak to tell (the review the verdict rests on). associated with greater gains than placebo in 1-RM bench press Adjunctive Ashwagandha (Withania somnifera) Supplementation and Resistance-Training Adaptations in Healthy Adults: A Systematic Review and Random-Effects Meta-Analysis of Muscular Strength, Chest Circumference, and Body CompositionPubMed 42738987
2. Systematic review, 2026; 20 studies, 1,249 people: improves. muscle strength (SMD = 0.58; 95% CI: 0.12-1.04; P = 0.013; I2 = 56.9%) Effects of Withania somnifera (L.) Dunal (Ashwagandha) on cognitive and physical function in adults: a systematic review and meta-analysisPubMed 42199854
3. Meta-analysis, 2026; 13 studies, 599 people; young adults or athletes: unclear: evidence too weak to tell. strength effects were positive but uncertain Effects of Withania somnifera (Ashwagandha) Supplementation on Exercise Performance: A Systematic Review and Three-Level Meta-AnalysisPubMed 42356302
4. Systematic review, 2026; 24 studies; healthy individuals and patients with stress-related or functional disorders: improves. Reported benefits included reduction of stress and anxiety, alleviation of depressive symptoms, improved sleep quality, … Clinical evidence for the adaptogenic effects of Withania somnifera and Rhodiola rosea - A systematic review with molecular interpretation of psychometric outcomesPubMed 41906501
5. Randomised trial, 2026; 83 people; recreationally active healthy adults aged 25-50: improves. significantly greater improvements in muscle strength Efficacy and safety of a sustained release ashwagandha root extract capsules on muscle strength and cardiorespiratory endurance in recreationally active individuals: a randomized, double-blind, placebo-controlled trialPubMed 42780946
6. Randomised trial, 2026; 56 people; team sports athletes during pre-season training: improves. Countermovement Jump (CMJ) improved significantly in ASH Ashwagandha Root Extract Stabilises Physiological Stress Responses in Male and Female Team Sports Athletes During Pre-Season TrainingPubMed 41599843
7. Randomised trial, 2026; 31 people; male amateur handball players: improves. significantly improved handgrip strength compared with placebo Effects of 8 days of Ashwagandha supplementation on strength, fatigue, soreness, and recovery in amateur handball players: A double-blind, randomized, placebo-controlled trialPubMed 41940566
8. Randomised trial, 2024; healthy volunteers: improves. Evaluation of Withania somnifera (L.) Dunal (Ashwagandha) on Physical Performance, Biomarkers of Inflammation, and Muscle Status in Healthy Volunteers: A Randomized, Double-Blind, Placebo-Controlled StudyPubMed 39381480
9. Randomised trial, 2023; 73 people; healthy adults performing resistance training: improves. AG caused greater improvement in bench press Effects of Ashwagandha ( Withania somnifera) standardized root extract on physical endurance and VO 2max in healthy adults performing resistance training: An eight-week, prospective, randomized, double-blind, placebo-controlled studyPubMed 38988644
10. Randomised trial, 2015; 57 people; healthy young men engaged in resistance training: improves. significantly greater increases in muscle strength on the bench-press exercise Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trialPubMed 26609282
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Sleep quality
The best available review (2026, 24 studies) found an improvement in sleep quality. That review studied healthy individuals and patients with stress-related or functional disorders. All 9 studies read agree. The evidence is moderate.
9 studies counted of 11 read: 3 reviews and 6 trials (547 people in the trials).
1. Systematic review, 2026; 24 studies; healthy individuals and patients with stress-related or functional disorders: improves (the review the verdict rests on). improved sleep quality, enhancement of cognitive functions Clinical evidence for the adaptogenic effects of Withania somnifera and Rhodiola rosea - A systematic review with molecular interpretation of psychometric outcomesPubMed 41906501
2. Meta-analysis, 2024; 5 studies, 254 people; patients with anxiety and/or insomnia: improves. Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysisPubMed 39083548
3. Meta-analysis, 2021; 5 studies, 400 people; adults 18 years old and above: improves. significant effect on overall sleep (Standardized Mean Difference -0.59 Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysisPubMed 34559859
4. Randomised trial, 2026; 135 people: improves. Sleep quality, psychological well-being, and eating behavior significantly improved from baseline to day 60 in … Efficacy and safety of Ashwagandha root extract sustained-release (AshwaSR) capsules in healthy adult, stressed subjects: A randomized, double-blind, placebo-controlled, parallel-group, 3-arm clinical trialPubMed 41824889
5. Randomised trial, 2026; 66 people; postmenopausal women aged 45-65 years: improves. significantly greater improvements in sleep quality Effects of Withania somnifera root extract on sleep quality, body composition, and menopausal symptoms in postmenopausal women: a randomized, double-blind, placebo-controlled trialPubMed 42742071
6. Randomised trial, 2025; 90 people: improves. improvements in PSS, BAI, and PSQI scores A New Ashwagandha Formulation (Zenroot™) Alleviates Stress and Anxiety Symptoms While Improving Mood and Sleep Quality: A Randomized, Double-Blind, Placebo-Controlled Clinical StudyPubMed 40875185
7. Randomised trial, 2024; 52 people; healthy adults with sleep problems: improves. Changes in the visual analogue scale (VAS) for sleep quality were significantly higher in the … Effectiveness of Enriched Milk with Ashwagandha Extract and Tryptophan for Improving Subjective Sleep Quality in Adults with Sleep Problems: A Randomized Double-Blind Controlled TrialPubMed 39189195
8. Randomised trial, 2022; 60 people; healthy college students: improves. group membership affected final sleep (58.4 ± 12.4 vs. 48.2 ± 15.0 The Impact of Ashwagandha on Stress, Sleep Quality, and Food Cravings in College Students: Quantitative Analysis of a Double-Blind Randomized Control TrialPubMed 35984871
9. Randomised trial, 2020; 144 people; healthy adults with non-restorative sleep: improves. 72% increase in self-reported sleep quality A randomized, double blind, placebo controlled study to evaluate the effects of ashwagandha (Withania somnifera) extract on sleep quality in healthy adultsPubMed 32540634
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.
Stress
The best available review (2022, 12 studies, 1,002 people) found a large improvement in stress. That review studied adults aged 25 to 48 years. 8 of the 10 studies read agree; 2 found no clear difference. The evidence is limited.
10 studies counted of 10 read: 5 reviews and 5 trials (355 people in the trials).
1. Meta-analysis, 2022; 12 studies, 1,002 people; adults aged 25 to 48 years: improves (the review the verdict rests on). Does Ashwagandha supplementation have a beneficial effect on the management of anxiety and stress? A systematic review and meta-analysis of randomized controlled trialsPubMed 36017529
2. Meta-analysis, 2026; 22 studies: improves. Effects of ashwagandha (Withania somnifera) on mental health in adults: A systematic review and dose-response meta-analysis of randomized controlled trialsPubMed 41644067
3. Meta-analysis, 2025; 6 studies, 488 people: no clear difference. Dual impact of Ashwagandha: Significant cortisol reduction but no effects on perceived stress - A systematic review and meta-analysisPubMed 40746175
4. Meta-analysis, 2024; 9 studies, 558 people; patients with psychosomatic disorders related to stress and anxiety: improves. significant effect of Ashwagandha formulations on the Perceived Stress Scale Effects of Ashwagandha (Withania Somnifera) on stress and anxiety: A systematic review and meta-analysisPubMed 39348746
5. Systematic review, 2023; 9 studies: improves. WS supplementation decreases cortisol secretion with no significant adverse effects. Effects of Withania somnifera on Cortisol Levels in Stressed Human Subjects: A Systematic ReviewPubMed 38140274
6. Randomised trial, 2026; 141 people; healthy adults with moderate stress and anxiety: improves. A proprietary herbal extract of ashwagandha root for stress and anxiety in healthy adults: a randomized, double-blind, three-arm, placebo-controlled efficacy and safety studyPubMed 41815853
7. Randomised trial, 2026; 60 people; patients with stress, anxiety, and pre-existing hypertension: improves. PSS scores decreased by 26.94%, 50.77%, and 30.47% Safety and efficacy of ashwagen (a standardized withania somnifera extract) in stress and anxiety with hypertension and associated cardiometabolic risk factors: a randomized, placebo-controlled trialPubMed 42105298
8. Randomised trial, 2025; 100 people; adults aged 19-65 years: improves. ARE showed significant improvements (P < 0.05) in PSS Efficacy and safety of Ashwagandha (Withania somnifera) root extract on stress and weight management in adults: a prospective, randomized, double-blind, placebo-controlled studyPubMed 41635453
9. Randomised trial, 2023; 54 people; healthy adults with mild to moderate symptoms: improves. PSS, GAD-7, and QOL scores improved significantly A standardized Ashwagandha root extract alleviates stress, anxiety, and improves quality of life in healthy adults by modulating stress hormones: Results from a randomized, double-blind, placebo-controlled studyPubMed 37832082
10. Randomised trial, 2023; overweight or mildly obese adults aged 40-75: no clear difference. improvements were not significantly different to the placebo group Exploring the efficacy and safety of a novel standardized ashwagandha (Withania somnifera) root extract (Witholytin®) in adults experiencing high stress and fatigue in a randomized, double-blind, placebo-controlled trialPubMed 37740662
Automated reading of the published studies (Decosa evidence engine), run 30 Sep 2026. It reads abstracts, can miss studies, and a repeat run can differ.

Key findings

Anxiety SymptomsStressImproves (the measure goes down)
Aerobic Exercise MetricsImproves (the measure goes up)
AlertnessInsomniaImproves (the measure goes up)

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Studies cited

49 studies from PubMed

Effects of Withania somnifera supplementation on cognitive function: A systematic review and meta-analysisPhytother Res, 2024 · PMID 38146803
Effects of Ashwagandha (Withania somnifera) Supplementation on Exercise Performance: A Systematic Review and Meta-AnalysisSports Med, 2024 · PMID 38529566
Ashwagandha (Withania somnifera) and its withanolides attenuate oxidative and inflammatory signaling in the nervous systemPhytomedicine, 2024 · PMID 38678538
Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysis of randomized controlled trialsSleep Med, 2023 · PMID 36804187
Clinical effects of Ashwagandha (Withania somnifera) root extract on human health: A systematic review of reviewsJ Ethnopharmacol, 2023 · PMID 37062481
A Comprehensive Review on Pharmacological Activity of Withania somnifera (Ashwagandha)Curr Drug Discov Technol, 2023 · PMID 37234185
Effects of Ashwagandha (Withania somnifera) on Testosterone Levels: A Systematic Review and Meta-AnalysisPhytomedicine, 2022 · PMID 35371298
Ashwagandha (Withania somnifera)-Current Research on the Health-Promoting Activities: A Narrative ReviewPharmaceutics, 2022 · PMID 35553682
Withania somnifera (L.) Dunal: A review of chemical composition and pharmacological activitiesJ Ethnopharmacol, 2022 · PMID 34883514
Efficacy of Ashwagandha (Withania somnifera) in Improving Cardiorespiratory Endurance and Recovery in Healthy Athletic Adults: A Systematic ReviewNutrients, 2021 · PMID 33599941
Safety of Ashwagandha Root Extract: A Randomized, Placebo-Controlled, Study in Healthy VolunteersComplement Ther Med, 2021 · PMID 35973005
Examining the Neuroprotective Effects of Ashwagandha: Brain-Derived Neurotrophic Factor in RatsNeurochem Int, 2019 · PMID 30466985
Evaluation of antioxidant potential of Rasayana drugs in healthy human volunteersAyu, 2014 · PMID 25364199
An Overview on Ashwagandha: A Rasayana (Rejuvenator) of AyurvedaAfr J Tradit Complement Altern Med, 2011 · PMID 32557429
Effects of Withania somnifera in patients of schizophrenia: A randomized, double blind, placebo controlled pilot trial studyIndian J Pharmacol · PMID 24014929
Adjunctive Use of a Standardized Extract of Withania somnifera (Ashwagandha) to Treat Symptom Exacerbation in Schizophrenia: A Randomized, Double-Blind, Placebo-Controlled StudyJ Clin Psychiatry · PMID 29995356
Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trialJ Int Soc Sports Nutr · PMID 26609282
Exploratory study to evaluate tolerability, safety, and activity of Ashwagandha (Withania somnifera) in healthy volunteersJ Ayurveda Integr Med · PMID 23125505
Effects of an Aqueous Extract of Withania somnifera on Strength Training Adaptations and Recovery: The STAR TrialNutrients · PMID 30463324
Effects of eight-week supplementation of Ashwagandha on cardiorespiratory endurance in elite Indian cyclistsJ Ayurveda Integr Med · PMID 23326093
Effects of Ashwagandha ( Withania somnifera) on Physical Performance: Systematic Review and Bayesian Meta-AnalysisJ Funct Morphol Kinesiol · PMID 33670194
Body Weight Management in Adults Under Chronic Stress Through Treatment With Ashwagandha Root Extract: A Double-Blind, Randomized, Placebo-Controlled TrialJ Evid Based Complementary Altern Med · PMID 27055824
Does Ashwagandha supplementation have a beneficial effect on the management of anxiety and stress? A systematic review and meta-analysis of randomized controlled trialsPhytother Res · PMID 36017529
A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adultsIndian J Psychol Med · PMID 23439798
Adaptogenic and Anxiolytic Effects of Ashwagandha Root Extract in Healthy Adults: A Double-blind, Randomized, Placebo-controlled Clinical StudyCureus · PMID 32021735
Efficacy of Withania somnifera on seminal plasma metabolites of infertile males: a proton NMR study at 800 MHzJ Ethnopharmacol · PMID 23796876
Withania somnifera Improves Semen Quality in Stress-Related Male FertilityEvid Based Complement Alternat Med · PMID 19789214
Withania somnifera improves semen quality by regulating reproductive hormone levels and oxidative stress in seminal plasma of infertile malesFertil Steril · PMID 19501822
Clinical Evaluation of the Spermatogenic Activity of the Root Extract of Ashwagandha (Withania somnifera) in Oligospermic Males: A Pilot StudyEvid Based Complement Alternat Med · PMID 24371462
Comparative evaluation of the effects of Withania somnifera with pentoxifylline on the sperm parameters in idiopathic male infertility: A triple-blind randomised clinical trialAndrologia · PMID 29770466
A double-blind, placebo-controlled evaluation of the anxiolytic efficacy ff an ethanolic extract of withania somniferaIndian J Psychiatry · PMID 21407960
Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974PLoS One · PMID 19718255
Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysis.Hum Psychopharmacol · PMID 39083548
Randomized placebo-controlled adjunctive study of an extract of withania somnifera for cognitive dysfunction in bipolar disorderJ Clin Psychiatry · PMID 24330893
Efficacy and Safety of Ashwagandha (Withania somnifera (L.) Dunal) Root Extract in Improving Memory and Cognitive FunctionsJ Diet Suppl · PMID 28471731
Effect of standardized aqueous extract of Withania somnifera on tests of cognitive and psychomotor performance in healthy human participantsPharmacognosy Res · PMID 24497737
A Randomized, Double-Blind, Placebo-Controlled, Crossover Study Examining the Hormonal and Vitality Effects of Ashwagandha ( Withania somnifera) in Aging, Overweight MalesAm J Mens Health · PMID 30854916
Efficacy of Ashwagandha (Withania somnifera Dunal. Linn.) in the management of psychogenic erectile dysfunctionAyu · PMID 22529644
Efficacy and Safety of Ashwagandha Root Extract in Subclinical Hypothyroid Patients: A Double-Blind, Randomized Placebo-Controlled TrialJ Altern Complement Med · PMID 28829155
An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract: A randomized, double-blind, placebo-controlled studyMedicine · PMID 31517876
In vivo effects of Ashwagandha (Withania somnifera) extract on the activation of lymphocytesJ Altern Complement Med · PMID 19388865
Evaluation of the efficacy of Withania somnifera (Ashwagandha) root extract in patients with obsessive-compulsive disorder: A randomized double-blind placebo-controlled trialComplement Ther Med · PMID 27515872
Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysisPLoS One · PMID 34559859
Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled StudyCureus · PMID 31728244
Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Improving Sexual Function in Women: A Pilot StudyBiomed Res Int · PMID 26504795
A randomized, double blind placebo controlled study of efficacy and tolerability of Withaina somnifera extracts in knee joint painJ Ayurveda Integr Med · PMID 27647541
Hypoglycemic, diuretic and hypocholesterolemic effect of winter cherry (Withania somnifera, Dunal) rootIndian J Exp Biol · PMID 11116534
Efficacy of Ashwagandha (Withania somnifera [L.] Dunal) in improving cardiorespiratory endurance in healthy athletic adultsAyu · PMID 26730141
Effect of Withania somnifera (Ashwagandha) on the development of chemotherapy-induced fatigue and quality of life in breast cancer patientsIntegr Cancer Ther · PMID 23142798

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What the published studies found

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Key findings

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Studies cited

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