Ashwagandha (Withania somnifera) is an herb thats been used in Ayurvedic medicine for many years. Ashwagandha means Smell of Horse,which refers to the fresh roots distinct horsey smell, and the traditional belief that ingesting the herb will confer the strength and virility of a horse.

Ashwagandha is an adaptogen. Adaptogens are substances that help our body to adapt to physical, mental, and metabolic stressors. Ashwagandha has been used most extensively to prevent anxiety. It has also been used for relieving insomnia and stress-induced depression. Ashwagandha can significantly reduce cortisol concentrations and the immunosuppressive effect of stress.

Beyond reducing stress levels, ashwagandha can improve physical performance in both sedentary people and athletes, as well as reduce Low-density Lipoprotein (LDL) cholesterol. Ashwagandha can improve the formation of memories, and may be able to treat Alzheimers disease, though more human evidence is needed before supplementation can be recommended specifically for Alzheimers.

Ashwagandha is traditionally recommended for cancer patients as well. Although it has been found to have anti-cancer activity in cultured cancer cells and certain animal models, it is important to note that there is no human evidence for ashwagandhas ability to treat cancer. It is, however, a great supplement to reduce immunosuppression. It can also ease the pain of chemotherapy treatment by greatly reducing stress and fatigue. Ashwagandha should not be used for cancer treatment, but it makes a great adjuvant therapy, meaning it may be helpful when taken alongside other treatments.

Heres a quick summary of the benefits of ashwagandha across many different functions, then well dive deeper into how ashwagandha works, including the science behind it.

  • Lowers stress and cortisol.
  • Activity on GABA receptors helps with anxiety, some types of depression, and assists in quality sleep.
  • Modulates the inflammation response.
  • Modulates the immune system.
  • Increases testosterone in both infertile as well as healthy men.
  • Supports womens hormonal health.
  • Supports healthy thyroid hormone function.
  • Increases strength, endurance (including VO2 Max) and muscle mass.
  • Helps protect the nervous system from neurodegeneration.
  • May act as a nootropic, assisting memory, learning, reaction times and other forms of cognition.
  • Protects DNA.

Lower Stress and Cortisol

In quite a few studies ashwagandha has been shown to lower self-perceived levels of stress, as well as cortisol levels (the stress hormone) in the body. One placebo-controlled study with 64 subjects, including both men and women found that after 60 days stress and cortisol were significantly reduced.

Ashwagandha also appears to suppress some of the neuronal excitation in response to stress, and many people have found that ashwagandha helps in cases of anxious or depressed thinking.


The Latin name, somnifera, comes from somnus, which means to sleep.This is not a plant that will knock you out like some others, but taking it during the day, many people notice an easier time falling asleep, with overall improved sleep quality.

Some research in rats looked at the mechanism by which ashwagandha brings its sleep-inducing effects. This appears to be through the signaling of the GABA-A receptor. GABA being a neurotransmitter that helps not only with sleep, but with feeling calm, this is likely part of its stress effects too.

Testosterone and Sperm Health

If cortisol is too high, this will inhibit all of the goodhormones (progesterone, testosterone, DHEA, etc.) as it steals away the building materials used to make them. Under excessive stress, the body will preferentially make more cortisol to deal with such stress, and therefore create less of the other hormones. This is often called Pregnenolone Steal.

In several human studies looking at infertile men, consistent results have seen the increases of testosterone and sperm quality. The first of these saw increases in testosterone and luteinizing hormone, while follicle-stimulating hormone and prolactin went down. Another study found a 15% increase in testosterone in young, healthy men (not infertile).

Females too!!

Ashwagandha also supports womens hormone health, though this is not as well studied. In those same male studies, Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH) were affected. Women make use of these hormones even more so than men. One study looking at female sexual function, found ashwagandha supplementation increased scores on Female Sexual Function Index (FSFI) over eight weeks. This included significant improvements in desire, arousal, lubrication, orgasm, satisfaction and comfort.

Another area that ashwagandha has a reputation for helping in is modulating the thyroid hormones, and thus being used in both cases of hyper- and hypothyroidism. Until recently, only rat studies have investigated ashwagandhas effects of thyroid hormone levels thus far. One study showed an increase in T4, without T3. The other showed an increased in both T4 and T3.

Earlier this year a placebo-controlled human trial with fifty subjects found that ashwagandha supplementation normalized TSH, T3 and T4 in people with sub-clinical hypothyroidism.

Increases in Endurance, Strength and Muscle Mass

In the aforementioned study, where normal, young men had their testosterone increase 15% with the use of testosterone, there were also increases in strength in the bench press and leg extension, as well as increased muscle size in the chest and arms. Body fat decreased too. All these happened in the ashwagandha group more so than the placebo group.

Another trial found increases to VO2 Max, velocity and power. Another study looking at cyclists (elite athletes) found improved cardiorespiratory endurance, specifically VO2 Max and time to exhaustion.

Neuroprotective and Nootropic

Ashwagandha is being investigated for a wide range of effects in various issues of the central nervous system, including neurodegeneration. One study looking at human neuronal cells found protective effects of ashwagandha against β-amyloid induced toxicity;beta-amyloid being a plaque that forms in the brain tissue found in Alzheimers patients.

Also, ashwagandha interacts in many ways with the nervous system, including activity on several neurotransmitter receptors. This includes inhibition of butyrylcholinesterase and acetylcholinesterase. Butyrylcholinesterase activity may help with drug addiction. Acetylcholinesterase catalyzes breakdown of acetylcholine, a neurotransmitter, which is used for memory, learning and cognition.

Even if youre not degenerating, there is some research showing that ashwagandha may act as a nootropic, meaning it can help improve things from baseline. Ashwagandha has been shown to induce neurogenesis, which is the growth of new neurons, primarily but boosting production of brain derived neurotropic factor (BDNF).

Immunomodulating and Anti-Aging Activity

Different studies show that sometimes ashwagandha suppresses the immune system, while other times it increases activity. This shows that it is immunomodulating, with dual direction activity.

Ashwagandha also helps to modulate the inflammation response, by inhibiting NF-κB and AP-1 transcription factors, both of which are important for protecting your DNA. In addition to this, ashwagandha increased telomerase activity in cell lines in several studies as well.

Taking ashwagandha during chemotherapy helps lessen fatigue and improves quality of life- as occurred in 100 breast cancer patients in one study.

So the bottom line is that Ashwagandha is a great all-purpose herb with numerous health benefits! Check out the best source of it here:

Thanks to Lost Empire Herbs for much of the data on this amazing herb!

Live great,

Dr. Eric