Guide to Ashwagandha - Benefits, Best Type, Dosage and Side Effects

Ashwagandha Root Supplement Brainpower Nootropics KSM 66

Otherwise known as Indian ginseng, winter cherry or its botanical name Withania somnifera, Ashwagandha is a Sanskrit term that refers to ‘smell of a horse’. This is because it is believed to confer the strength and virility of a horse. It is a small shrub with yellow flowers and red fruit. However it’s the roots that are the prized part of the plant given that these possess the highest concentrations of the all-important withanolides – the active ingredients.

Ashwagandha is one of the most widely used herbs in traditional Indian medicine (Ayurveda) and has been used for centuries because of its long list of impressive health benefits. Unlike a number of supplements that make bold claims but have little to back it up, Ashwagandha has been heavily researched and has strong evidence to substantiate its claims. In this blog post, we are going to discuss all things ashwagandha to hopefully shed light on the reasons why so many people are utilising it to improve their physical and mental wellbeing.

What are the Health Benefits?

As alluded to earlier, there are a number of health benefits from supplementing with this botanical and its natural properties could be of benefit to most, if not all of us.

Mental Health and Sleep

Just like rhodiola rosea and Korean ginseng, Ashwagandha is an adaptogen. Adaptogen’s are herbs that can help the body overcome physical and mental stress. The withanolides have been consistently shown to decrease cortisol (the body’s stress hormone), in turn providing a number of benefits to anxiety levels, sleep quality, fatigue and overall perceived quality of life.

One study that recruited 64 men and women with a history of chronic stress found that 600mg of KSM-66® Ashwagandha daily for 8 weeks led to 28% lower cortisol levels. The research team also asked the participants to complete the Depression & Anxiety Stress-Scale before and after 8 weeks of supplementation. The group on average saw a 77% reduction in depression, a 75% decrease in anxiety and 44% lower levels of stress from taking the daily supplement (1).

Going back to its botanical name, Withania somnifera, somnifera in Latin means sleep inducing. Because of this, and its ability to attenuate stress and anxiety, it should come as no surprise that this herb can improve sleep. Again using 600mg of daily KSM-66®, researchers found that 10 weeks of daily supplementation led to significant improvements in all measured parameters of sleep. Specifically, the time taken to fall asleep shortened, length of time asleep increased, sleep quality improved and there were less episodes of waking during the night. Additionally, the volunteers experienced large reductions in their anxiety levels (2).

Although researchers do not fully understand how these benefits come about, we do know that the withanolides decrease cortisol, Dehydroepiandrosterone (DHEA) and the activity of the hypothalamic-pituitary-adrenal axis which is known to have a calming effect (3). The above studies are just two examples of Ashwagandha’s natural power and shows how beneficial it can be for people who struggle with the fast-paced, ‘always on’ culture of the modern world.

As a Nootropic

Nootropics are nutrients that boost brain function and Ashwagandha can certainly be classed as one. We have already seen how it can improve sleep, stress, mood and anxiety, but research has elucidated other benefits too. One study that provided 500mg of Ashwagandha daily found that supplementation led to improvements in working memory and reaction time (4). Similar results have been published in The Journal of Dietary Supplements which saw participants perform better during numerous memory tests, have a longer attention span and improve their information processing speed. Like previous studies, the researchers used 600mg of KSM-66® daily (5).

Systemic reviews and meta-analysis studies are much revered in scientific circles as they collate the results of numerous studies that are similar in nature. Because of this, their conclusions tend to be strong. One systematic review recently concluded that “Withania somnifera extract improved performance on cognitive tasks, executive function, attention, and reaction time. It also appears to be well tolerated, with good adherence and minimal side effects” (6). This last sentence is really important and should give people the peace of mind that they can improve their wellbeing without having to tolerate side-effects.

Fertility and Reproductive Function

Ashwagandha is becoming increasingly popular with those aiming to start a family. Looking firstly at the benefits for men, studies have shown that it’s particularly beneficial.

One study in 75 infertile men showed that daily supplementation with Withania somnifera root extract improved all parameters of sperm health, specifically sperm count, quality and motility (7). Researchers believe this benefit can be put down to its impact on reproductive hormones like testosterone as well as its powerful antioxidant potential which helps to protect the sperm cells (3,7). As withanolines are powerful antioxidants with anti-inflammatory properties, they can also benefit older men by protecting the prostate too (8).

Although there isn’t as much research in women, one study of note found that taking 600mg of KSM-66® for 8 weeks significantly improved scores on the Female Sexual Function Index. Specifically, the researchers found marked improvements in scores for arousal, lubrication, orgasms, satisfaction as well as an increase in sexual encounters (9).

Exercise Performance

Athletes and gym-goers are also becoming aware of this powerful herb. What is fascinating is that it can benefit aerobic as well as anaerobic exercise, something very few supplements can do.

In trained cyclists, daily consumption of 1000mg of root extract for 8 weeks has been shown to improve VO2 max (the amount of oxygen the body can utilise per minute) by 13% as well as significantly increasing the time taken to reach exhaustion during a cycling stress test (10). It is thought that the benefits to aerobic exercise capacity are due to an increase in red blood cells and hemoglobin which allows more oxygen to be carried to the working muscles (11).

Backing up the reference to horse-like strength, Ashwagandha has shown numerous times its ability to increase muscular power. One study found that 750mg-1250mg of root extract taken every day for a month led to previously untrained people increasing lower back and leg strength to a much greater extent that those given a placebo (12). A 2015 study published in the highly respected Journal of the International Society of Sports Nutrition provides complementary findings. The research team found that 600mg of KSM-66® taken daily for 8 weeks significantly increased bench press and leg-extension strength as well as muscle mass compared to participants who were unknowingly given a placebo instead (13).

So it seems clear that if muscle strength and size is a goal of yours then Ashwagandha is a supplement you should definitely consider and one that is likely to work well with other tried and tested exercise boosters such as creatine monohydrate.

What is the Best Type?

There are many different types of Ashwagandha and identifying the right supplement might feel overwhelming. However there are a few key aspects to look out for which will ensure you buy a premium quality supplement.As we touched on earlier, you want to look for an extract which consists of the root only as the root is highest in the health-promoting withanolides. It would also be a good idea to search for an organic certified extract as this means that no harmful chemicals or pesticides will have been used in its cultivation. Similarly, we recommend that you quiz manufacturers on how it’s extracted. Water-extraction is preferred as this is natural and helps to preserve the activity of the withanolides.

As you will have noticed, the vast majority of the research has used KSM-66®. This patented extract is the market leader as it’s got a very high concentration of active ingredients as it’s sourced from the roots only. It is also organic and benefits from being water-extracted. Another important point to consider is that KSM-66® Ashwagandha is lowest in the cytotoxic compound known as Withaferin A.

If you do your due diligence and are prepared to pay a bit extra, it will not be hard to find a high-quality, genuine supplement that provides all of the aforementioned health benefits.

How Much Should I Take?

Some studies have used more and others less, but as we have seen the majority of studies have used 300mg of KSM-66® twice per day, so a total of 600mg. If you are looking for an organic KSM-66® Ashwagandha supplement that provides the recommended 600mg per day you can find this here. You will be pleased to know that there have been very few reported side effects from daily supplementation at this dose and the few that have been reported are mild. Choosing a supplement with low levels of Withaferin A is the best way to guarantee this.


Hopefully this blog post has helped you to understand enough about this exciting botanical so you can decide whether it would be a good supplement to add to your arsenal. If you are still unsure about this supplement or another, get in touch with one of our friendly experts who will be more than happy to help.

To conclude this article here is the key points summarised:


Ashwagandha is highly beneficial for mood, anxiety, and stress reduction. It is also proven to boost brain function as well as improve sleep quality, fertility and exercise performance.


For those wanting to know how much Ashwagandha to take, research shows that 600mg of KSM-66® is the optimum amount to take daily.

When to Take

Ashwagandha is usually taken twice per day. It is common to take a dose in the morning and then again in the afternoon. For those looking to improve their sleep, it would be most beneficial to take it in the evening.

Side Effects

Ashwagandha is very safe, with very few side effects noted. Like many supplements, it can cause mild stomach upset in some individuals. However, this may not be due to the herb; it may be due to other materials in the tablet/capsule. Look for an organic supplement to minimise this risk.


Ashwagandha has no major interactions but it has the potential to contraindicate with sedative medication as it naturally causes relaxation. Like with all supplements, it is recommended that you speak with your GP or pharmacist before taking it with prescription medication.















Leave a comment

Please note, comments must be approved before they are published