Ashwagandha is an ancient medicinal herb.
It’s classified as an adaptogen, meaning that it can help your body manage stress.
Ashwagandha also provides numerous other benefits for your body and brain.
For example, it can boost brain function, lower blood sugar and cortisol levels, and help fight symptoms of anxiety and depression.
Here are 12 benefits of ashwagandha that are supported by science.
1. Is an ancient medicinal herb
Ashwagandha is one of the most important herbs in Ayurveda, a form of alternative medicine based on Indian principles of natural healing.
"Ashwagandha" is Sanskrit for "smell of the horse," which refers to both its unique smell and ability to increase strength.
Its botanical name is Withania somnifera, and it’s also known by several other names, including Indian ginseng and winter cherry.
The ashwagandha plant is a small shrub with yellow flowers that's native to India and North Africa. Extracts or powder from the plant's root or leaves are used to treat a variety of conditions.
Many of its health benefits are attributed to its high concentration of withanolides, which have been shown to fight inflammation and tumor growth (
Summary Ashwagandha is a prominent herb in Indian Ayurvedic medicine and has become a popular supplement due to its health benefits.
2. Can reduce blood sugar levels
In several studies, ashwagandha has been shown to lower blood sugar levels.
One test-tube study found that it increased insulin secretion and improved insulin sensitivity in muscle cells (
Additionally, in a 4-week study in people with schizophrenia, those treated with ashwagandha had an average reduction in fasting blood sugar levels of 13.5 mg/dL, compared with 4.5 mg/dL in those who received a placebo (
What's more, in a small study in 6 people with type 2 diabetes, supplementing with ashwagandha for 30 days lowered fasting blood sugar levels. However, the study didn’t include a control group, making the results questionable (
Summary Limited evidence suggests that ashwagandha reduces blood sugar levels through its effects on insulin secretion and sensitivity.
3. Might have anticancer properties
Animal and test-tube studies have found that withaferin — a compound in ashwagandha — helps induce apoptosis, which is the programmed death of cancer cells (
It also impedes the growth of new cancer cells in several ways (
First, withaferin is believed to promote the formation of reactive oxygen species (ROS) inside cancer cells, disrupting their function. Second, it may cause cancer cells to become less resistant to apoptosis (
In one study, mice with ovarian tumors treated with withaferin alone or in combination with an anti-cancer drug showed a 70–80% reduction in tumor growth. The treatment also prevented the spread of cancer to other organs (
Although no evidence suggests that ashwagandha exerts similar effects in humans, the current research is encouraging.
Summary Animal and test-tube studies have shown that withaferin, a bioactive compound in ashwagandha, promotes the death of tumor cells and may be effective against several types of cancer.
4. Can reduce cortisol levels
Cortisol is known as a stress hormone given that your adrenal glands release it in response to stress, as well as when your blood sugar levels get too low.
Unfortunately, in some cases, cortisol levels may become chronically elevated, which can lead to high blood sugar levels and increased fat storage in the abdomen.
In one study in chronically stressed adults, those who supplemented with ashwagandha had significantly greater reductions in cortisol, compared with the control group. Those taking the highest dose experienced a 30% reduction, on average (3).
Summary Ashwagandha supplements may help lower cortisol levels in chronically stressed individuals.
5. May help reduce stress and anxiety
Ashwagandha is perhaps best known for its ability to reduce stress.
Researchers have reported that it blocked the stress pathway in the brains of rats by regulating chemical signaling in the nervous system (
In a 60-day study in 64 people with chronic stress, those in the group that supplemented with ashwagandha reported a 69% reduction in anxiety and insomnia, on average, compared with 11% in the placebo group (
In another 6-week study, 88% of people who took ashwagandha reported a reduction in anxiety, compared with 50% of those who took a placebo (
Summary Ashwagandha has been shown to reduce stress and anxiety in both animal and human studies.
6. May reduce symptoms of depression
In one controlled 60-day study in 64 stressed adults, those who took 600 mg of high-concentration ashwagandha extract per day reported a 79% reduction in severe depression, while the placebo group reported a 10% increase (
However, only one of the participants in this study had a history of depression. For this reason, the relevance of the results is unclear.
Summary The limited research available suggests that ashwagandha may help reduce depression.
7. Can boost testosterone and increase fertility in men
In one study in 75 infertile men, the group treated with ashwagandha showed increased sperm count and motility.
The researchers also reported that the group who took the herb had increased antioxidant levels in their blood.
In another study, men who received ashwagandha for stress experienced higher antioxidant levels and better sperm quality. After 3 months of treatment, 14% of the men's partners had become pregnant (
Summary Ashwagandha helps increase testosterone levels and significantly boosts sperm quality and fertility in men.
8. May increase muscle mass and strength
In a study to determine a safe and effective dosage for ashwagandha, healthy men who took 750–1,250 mg of pulverized ashwagandha root per day gained muscle strength after 30 days (
In another study, those who took ashwagandha had significantly greater gains in muscle strength and size. It also more than doubled their reductions in body fat percentage, compared with the placebo group (
Summary Ashwagandha has been shown to increase muscle mass, reduce body fat, and increase strength in men.
9. May reduce inflammation
It has also been shown to decrease markers of inflammation, such as C-reactive protein (CRP). This marker is linked to an increased risk of heart disease.
In one controlled study, the group who took 250 mg of standardized ashwagandha extract daily had a 36% decrease in CRP, on average, compared with a 6% decrease in the placebo group (3).
Summary Ashwagandha has been shown to increase natural killer cell activity and decrease markers of inflammation.
10. May lower cholesterol and triglycerides
In addition to its anti-inflammatory effects, ashwagandha may help improve heart health by reducing cholesterol and triglyceride levels.
Animal studies have found that it significantly decreases levels of these blood fats.
One study in rats found that it lowered total cholesterol and triglyceride levels by 53% and nearly 45%, respectively (
In a 60-day study in chronically stressed adults, the group taking the highest dosage of standardized ashwagandha extract experienced a 17% decrease in LDL (bad) cholesterol and an 11% decrease in triglycerides, on average (3).
Summary Ashwagandha may help reduce the risk of heart disease by decreasing cholesterol and triglyceride levels.
11. May improve brain function, including memory
Research has shown that it promotes antioxidant activity that protects nerve cells from harmful free radicals.
In one study, rats with epilepsy that were treated with ashwagandha had nearly a complete reversal of spatial memory impairment. This was likely caused by a reduction in oxidative stress (
Although ashwagandha has traditionally been used to boost memory in Ayurvedic medicine, only a small amount of human research has been conducted in this area.
In one controlled study, healthy men who took 500 mg of standardized extract daily reported significant improvements in their reaction time and task performance, compared with men who received a placebo (
Another 8-week study in 50 adults showed that taking 300 mg of ashwagandha root extract twice daily significantly improved general memory, task performance, and attention (
Summary Ashwagandha supplements may improve brain function, memory, reaction time, and the ability to perform tasks.
12. Is safe for most people and widely available
Ashwagandha is a safe supplement for most people, although its long-term effects are unknown.
However, certain individuals should not take it, including pregnant and breastfeeding women.
People with autoimmune diseases should also avoid ashwagandha unless authorized by a healthcare provider. This includes people with conditions like rheumatoid arthritis, lupus, Hashimoto's thyroiditis, and type 1 diabetes.
Additionally, those on medication for thyroid disease should be careful when taking ashwagandha, as it may increase thyroid hormone levels in some people.
It may also decrease blood sugar and blood pressure levels, so medication dosages may need to be adjusted if you take it.
The recommended dosage of ashwagandha depends on the type of supplement. Extracts are more effective than crude ashwagandha root or leaf powder. Remember to follow instructions on labels.
Standardized root extract is commonly taken in 450–500-mg capsules once or twice daily.
It’s offered by several supplement manufacturers and available from various retailers, including health food stores and vitamin shops.
There's also a great selection of high-quality supplements available online.
Summary Although ashwagandha is safe for most people, certain individuals shouldn't use it unless authorized to do so by their healthcare provider. Standardized root extract is commonly taken in 450–500-mg capsules once or twice per day.
The bottom line
Ashwagandha is an ancient medicinal herb with multiple health benefits.
It can reduce anxiety and stress, help fight depression, boost fertility and testosterone in men, and even boost brain function.
Supplementing with ashwagandha may be an easy and effective way to improve your health and quality of life.