Our evidence-based analysis of Ashwagandha features unique references to scientific papers and anecdotal reports.

What Is Ashwagandha?

Ashwagandha is a plant native to India, where it has been used for centuries as a tonic and restorative. Modern nootropic users are rediscovering this ancient herb, which may indirectly enhance cognition by fighting the effects of stress and improving mood.

Ayurvedic medicine uses Ashwagandha as a treatment for various health issues, but it is most typically prescribed to extend longevity, promote recovery, and increase sexual function.

Extensive research confirms that that Ashwagandha is a powerful adaptogen.‍[1] Adaptogens are natural substances that help the body adapt to stress and normalizes the function of the adrenal, endocrine, and other bodily systems.

Many users report that it reduces anxiety, enhances mood, and relieves insomnia and other sleep problems.‍[2]

Benefits and Effects of Ashwagandha

A growing body of research indicates that Ashwagandha is a safe and effective supplement with the potential for protecting and enhancing cognitive function and promoting general health and well-being.

Reduce Stress, Anxiety, and Depression

Ashwagandha is best known to modern users for its documented ability to fight stress and anxiety.‍[3]

Clinical trials confirm that Ashwagandha has powerful anti-anxiety effects, capable of reducing both generalized and social anxiety in patients diagnosed with generalized anxiety disorder, but particularly effective in the context of chronic stress.‍[4]

Human studies also show that it has potential as a treatment for depression and panic disorder.‍[5]

One of the most promising effects of Ashwagandha is its ability to protect and promote overall health and well-being by reducing the levels of the stress hormone cortisol throughout the body.

High cortisol levels are strongly associated with a host of negative health implications, including impaired immune function, weight gain, high blood pressure, and heart disease.‍[6]

A 60-day regimen of Ashwagandha was shown to effectively reduce levels of serum cortisol in patients with chronic anxiety and mental stress.‍[7]

May Indirectly Enhance Cognition

There are limited studies on Ashwagandha’s ability to directly improve memory and cognitive abilities, but its powerful adaptogenic capabilities may indirectly result in enhanced cognition.

Research has repeatedly demonstrated that anxiety can be a major factor in diminished cognitive ability, measurably impairing concentration, focus, and memory.‍[8]

In a small study of 20 healthy males, Ashwagandha improved both cognitive and psychomotor performance.‍[9]

In a review of Ayurvedic medicines with cognition-enhancing properties, Ashwagandha was noted as having potential as a treatment for childhood dyslexia.‍[10]

Animal studies show that daily supplementation with Ashwagandha effectively prevented cognitive decline by enhancing hippocampal plasticity.‍[11]

Ashwagandha is currently being studied as a possible treatment for cognitive decline related to dementia‍[12] and HIV.‍[13]

Treatment for Various Health Issues

Ashwagandha has also been shown to have potential as a treatment for a variety of disorders.

Arthritis: Ashwagandha’s Ayurvedic use as a treatment for joint complaints appears to be confirmed by recent research. A 2015 Indian study involving more than 100 patients with rheumatoid arthritis indicated that after taking Ashwagandha for several weeks, more than half the participants had an observable decrease in arthritic symptoms, including pain, mobility problems, and tender and swollen joints.‍[14]

Alzheimer’s Disease: Ashwagandha is being studied as a potential treatment for Alzheimer’s and other neurodegenerative diseases. Recent research suggests that Ashwagandha inhibits the formation of beta-amyloid plaques, the amino acid formations known to accumulate in the brains of Alzheimer’s patients and interfere with cognitive processes.‍[15] Animal studies also show Ashwagandha has the potential to act as a neuroprotectant, preventing damage from the glutamate neurotoxicity typically associated with neurodegenerative disorders.‍[16]

Weight Management: Ashwagandha’s adaptogenic properties may be useful in the treatment of obesity. A study of 52 people diagnosed with chronic stress showed that two daily doses of 300 mg of Ashwagandha resulted in a significant drop in perceived stress and food cravings, as well as a decrease in serum cortisol and body weight.‍[17]

Improved Muscle Strength: Ayurvedic medicine’s classical use of Ashwagandha as a strength-improving tonic appears to be confirmed by a series of recent studies. Healthy males taking 300–1250 mg of Ashwagandha daily demonstrated measurable improvements in muscle strength in comparison to participants taking a placebo. Those on the Ashwagandha regimen increased their bench press and leg extension capability as well as muscle size, serum testosterone, and muscle recovery.‍[18]

Male Sexual Dysfunction and Infertility: A pilot study involving 46 male participants, all of whom had low sperm counts, showed remarkable results after a three-month regimen of 675 mg daily of high-potency Ashwagandha known as KSM-66. At the end of the trial, the participants taking Ashwagandha had a 167% increase in sperm count, a 53% increase in semen volume, and a 57% increase in sperm motility. ‍[19]

Animal tests also showed that Ashwagandha increased sexual behavior, increased testicular sperm production, and raised serum testosterone levels.‍[20]

Blood Pressure: Studies indicate that Ashwagandha can produce a moderate but measurable reduction in blood pressure. A 2010 study involving approximately 100 participants, over six months, an average 1.6% decrease in systolic pressure and a 5.6% decrease in diastolic pressure were observed, along with a minor decrease in heart rate.‍[21]

Chemotherapy-induced Fatigue: While Ashwagandha is not a treatment for cancer, it appears to be a valuable adjunct therapy for cancer patients. A 2013 trial involving over 100 breast cancer patients in all stages of the disease showed that ashwagandha effectively reduced chemotherapy-induced fatigue and improved quality of life.‍[22]

Rejuvenation and Overall Health Improvement: A comprehensive scientific review of existing studies on Ashwagandha confirms a variety of therapeutic effects with no demonstrated toxicity. The review concluded that Ashwagandha has anti-inflammatory, antitumor, antistress, antioxidant, immunomodulatory, and rejuvenating properties, capable of exerting a positive influence on the endocrine, cardiopulmonary, and central nervous systems.‍[23]

How It Works

The exact mechanisms by which Ashwagandha works are not entirely understood. However, its main active substances are alkaloids and steroidal lactones that are collectively known as withanolides. The withanolides are believed to be responsible for Ashwagandha’s physiological activity.

One of the known mechanisms of withanolides is the modulation of circulating monoamine oxidase and GABA levels in the brain.‍[24] GABA is an amino acid that acts as an inhibitory neurotransmitter, countering to some extent the effects of the stimulatory neurotransmitter glutamate and thus serving as a natural tranquilizer.

Animal studies demonstrate that Ashwagandha enhances calmness without creating drowsiness as well as anti-depressant effects.‍[25]

Ashwagandha is believed to promote the formation of dendrites. Dendrites are extensions of nerve cells that receive signals from other neurons.‍[26] Increased dendrite formation is considered a marker of increased connectivity in the brain and is associated with enhanced cognition.

The active withanolides in Ashwagandha are also believed to have substantial antioxidant properties.‍[27] Antioxidants are chemical molecules that prevent potentially damaging oxidizing agents from affecting cells in the brain and body. Cells that have been affected by oxidation can turn into free radicals, molecules that scavenge and damage surrounding cells. The action of free radicals can trigger a chain reaction of cellular devastation that is strongly associated with aging and a variety of diseases, including Alzheimer’s disease.

Ashwagandha also appears to be an effective anti-inflammatory agent.‍[28] Inflammation is implicated in a wide range of disorders, and many of Ashwagandha’s benefits are believed to be associated with its anti-inflammatory properties.


Dosage recommendations for Ashwagandha extract, based on human studies, typically range from 300–500 mg, taken twice per day.‍[29]‍[30]

Ashwagandha should be taken with food.

Ashwagandha may increase the effects of tranquilizers, sedatives, or other anxiolytics, including alcohol and some nootropics.

It may also potentiate drugs taken to reduce blood pressure or regulate blood sugar, so use with caution if you’re taking other medications.


To fully experience Ashwagandha’s cognitive-enhancing effects, it does best when stacked with other supplements.

Please have a look at our All-Natural Nootropic Stack for some inspiration for a stack that contains Ashwagandha.

Side Effects

Ashwagandha appears to be exceptionally safe and well-tolerated when taken in moderate doses.

Side effects are rare and are typically associated with large doses

The most commonly reported side effects are indigestion and diarrhea, abdominal discomfort, and drowsiness.‍[31]

Ashwagandha could potentially interact with other supplements and medications. It may increase the effects of sedative drugs and other anxiolytics.

Women who are pregnant or nursing should not take Ashwagandha.

Infants and children should not take Ashwagandha due to limited safety information for these populations.

Where to Buy

We recommend Organic India Ashwagandha capsules that can be found on Amazon.

Another option is to order directly from a specialty vendor such as PureNootropics.net, as they carry Ashwagandha in its highly concentrated KSM-66 extract form, as well as a wide selection of other nootropics.

Closing Thoughts

Ashwagandha has been extensively studied and shown to be a potent adaptogen that helps the body and brain adapt to stress.

It’s also a proven anxiolytic that may improve mood and help regulate sleep. Its neuroprotective properties may help treat and prevent neurological disorders.

While Ashwagandha does not provide an immediate cognitive boost, it may indirectly increase cognitive abilities by lowering anxiety, lifting depression, and improving sleep quality.

It’s safe, well-tolerated, non-toxic even in large doses, and has very few side effects.

However, like most nootropics, its mechanisms of action are not entirely understood. Much of the research on some aspects of Ashwagandha has involved animal rather than human studies, and the full extent of its effects and potential interactions is unknown.


Planning to start a new supplementation regimen? See our medical disclaimer.

This page was last updated on July 16, 2021.