The Benefits of Ashwagandha (Withania Somnifera)

Long touted in alternative medicine as a miracle plant for a range of health benefits, Ashwagandha, “the king of Ayurvedic herbs”,  has been shown through recent scientific studies to be effective for the treatment of stress and anxiety, as well as a potentially beneficial supplement for improving mental alertness and sleep quality. Ashwangandha’s cell-regenerating properties make it a promising natural nootropic for those looking to manage stress and boost cognition.

Ashwagandha also has unique benefits for men, as it has been shown to naturally boost testosterone levels and improve male fertility.

What is Ashwagandha?

Ashwagandha, (scientific name: withania somnifera) is a small, fruit-bearing shrub originating in India, long-believed by practitioners of Ayurvedic medicine to have powerful healing properties.

What is Ayurvedic medicine?

Ayurvedic medicine, or Ayurveda, is an ancient alternative medicine system originating in India. It is based on holistic principles of balancing the mind and body by keeping the various “energies” that govern the body in harmony.

Though Ayurveda is considered pseudoscientific, many Ayurvedic medicines derived from plants and minerals have been observed over thousands of years to have health benefits. Scientific research into certain aspects of Ayurvedic medicine has provided evidence of the efficacy of many of the herbs and supplements used in the ancient healing system.

The benefits of Ashwagandha are said to be varied and wide-ranging, from reducing stress and slowing ageing, to improving athletic performance and increasing libido. As with many alternative medicines, the evidence for many of these claims is sparse – but some recent studies into the small ancient plant have produced promising results for a number of health benefits.

How does Ashwagandha work?

Ashwagandha contains chemicals that have a calming effect on the brain and body, facilitating a reduction in stress and inflammation. In Ayurvedic medicine, Ashwagandha belongs to a group of herbs classed as adaptogens. Adaptogens are believed to cause adaptive reactions to disease, as well as increase resistance to harmful chemical, physical and biological agents. Some of the claims about adaptogens in Ayurvedic medicine have been observed and supported by modern science over the years, and the anti-inflammatory effects are evident in a number of research studies.

In addition, more and more research into the benefits of Ashwagandha appear to support the theory that this adaptogenic herb plays a protective and regenerative role in the brain, working to reconstruct and strengthen all stages of neurotransmission; from the axons and dendrites of nerve cells, to the synapses where nerve cells communicate with each other.

Ashwaghanda’s cell-regeneration effects likely mean that it has cognitive benefits. Initial studies support the theory that Ashwaganhda could help to enhance memory, improve reaction times and boost mental alertness, making it a novel and natural nootropic.

Benefits of Ashwagandha

Though Ashwagandha is believed by many people to be beneficial for a wide range of different health issues, we will focus only on the benefits that have been supported through scientific studies. More research is needed to gain the full picture of the benefits and uses of Ashwagandha, but current research shows promising results in a number of areas.

Stress and Anxiety

There is solid scientific evidence for the claim that supplementing with Ashwagandha can help reduce stress. Researchers believe that Ashwagandha likely enhances GABA receptors (the receptors that calm your anxiety response) and boosts serotonin in the brain, inhibiting an overactive fight-or-flight reaction.

Animal trials have consistently shown an anxiolytic (anti-anxiety) effect in the brains of rats when subject to stressful situations.. More recently, these effects have also been observed in human studies. A meta study reviewing human trials of Ashwagandha and its effect on stress and anxiety concluded that Ashwagandha had significantly more impact on reducing stress and anxiety scores than a placebo.

Mental Alertness

Several studies into the cognitive effects of Ashwagandha discovered that this herbal drug helped repair severely damaged neurons in the brains of rats. These results show that Ashwagandha’s cell-regenerative properties make it a promising candidate for the treatment of neurodegenerative diseases in humans. Ashwagandha appears to improve general cognition too; a study involving healthy male participants showed significantly improved scores on a range of cognitive and psychomotor tests after supplementing with Ashwagandha for two weeks.

More research is needed into the cognitive benefits of Ashwagandha, but its neural-protective effects could result in general cognitive improvement in the areas of memory and learning.

Male fertility and sexual function

Ashwagandha may be a uniquely useful supplement for men, particularly those hoping to have children. In Ayurvedic medicine, Ashwagandha is commonly promoted as a substance which helps to restore vigour and vitality in men (the name literally translates to “the smell of the horse” in Sanskrit). Whether or not Ashwagandha can instill you with the strength and spirit of a mighty stallion, there is certainly some scientific evidence that it may improve men’s fertility. A clinical trial into 90 days of fertility treatment with Ashwagandha found significant improvements in both sperm generation and increased testosterone levels in the male participants.

As yet there is not enough evidence to conclude that Ashwagandha has any effect on male libido or sexual function, so more research may be needed in this area. However, the fact that Ashwagandha has been shown to increase testosterone levels means that it is likely to be a useful supplement for men. Combined with other efforts to naturally boost testosterone such as regular exercise and a healthy diet, Ashwagandha may be an effective supplement for men wanting to boost their energy levels and increase lean muscle mass.


Early studies have shown that Ashwagandha may also be helpful for improving sleep, as well as a potential treatment for insomnia. A controlled double-blind study found that its calming effect on the brain and body appeared not only to significantly improve participant’s ability to fall and stay asleep, but also had a positive impact on levels of alertness soon after waking.
More research is needed on the efficacy of Ashwagandha for improved sleep, but so far results have been promising. 

How to take Ashwagandha: dosage and side effects

Ashwagandha is widely available and usually sold in capsule form, but is also available as a powder and liquid. Dosage varies greatly, from 125 mg up to 1500 mg. The optimal dose for you will depend on your desired effects and what kind of benefits you would like to see.

There are minimal reported side-effects of Ashwagandha, and toxicity is low even in extremely high doses. However, there are no studies into its long term use, and it may interact with certain medicines (though there are currently no known serious interactions). Always check with your doctor before you start taking new supplements.

Ashwagandha dosage recommendations

For stress:

For stress and anxiety, similar benefits have been observed among participants given both 250 mg and 600 mg of an Ashwagandha supplement per day, indicating that a smaller dose of up to 300 mg is sufficient to manage stress.

For mental alertness and sleep quality:

A dose of 300 mg daily is sufficient to see improvements in both mental alertness and sleep quality. Supplements are best taken with food, either first thing in the morning with breakfast or after dinner before sleep.
Ashwagandha can cause a slight sedative effect in some people, so if you find yourself experiencing this it is best to take Ashwagandha at night to get the full benefits.  

For fertility:

For men wanting to boost their fertility, a higher dose over a limited period of time may be needed. In studies where Ashwagandha was shown to increase sperm production and quality, a dose of 5g per day appeared to be most effective.

Note: there are no reliable studies into the long-term use of Ashwagandha at high doses, so it is recommended that men take this higher dose only while trying to conceive. 

More research is needed to discover the full range of benefits of Ashwagandha, but initial studies have produced exciting results. Whether you’re looking to reduce stress, boost mental alertness, improve sleep or increase fertility, Ashwagandha, “the king of Ayurvedic herbs” could help.


A current study of adaptogens: A natural remedy for stress

Adaptogenic and Anxiolytic Effects of Ashwagandha Root Extract in Healthy Adults: A Double-blind, Randomized, Placebo-controlled Clinical Study

An Alternative Treatment for Anxiety: A Systematic Review of Human Trial Results Reported for the Ayurvedic Herb Ashwagandha (Withania somnifera)

Anxiolytic-antidepressant activity of Withania somnifera glycowithanolides: an experimental study

A preliminary review of studies on adaptogens: comparison of their bioactivity in TCM with that of ginseng-like herbs used worldwide

Ashwagandha Overview (NCIB)

Clinical Evaluation of the Spermatogenic Activity of the Root Extract of Ashwagandha (Withania somnifera) in Oligospermic Males: A Pilot Study

Effect of Ashwagandha on Tests of Cognitive and Psychomotor Performance

Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled Study

Neuritic regeneration and synaptic reconstruction induced by withanolide A

Withania somnifera Improves Semen Quality in Stress-Related Male Fertility