For hundreds of years, people have used the roots and orange-red fruit of ashwagandha for medicinal purposes. The herb is also known as Indian ginseng or winter cherry.
The name “ashwagandha” describes the smell of its root, meaning “like a horse.” By definition, ashwa means horse.
Practitioners use this herb as a general tonic to boost energy and reduce stress and anxiety. Some also claim that the herb may be beneficial for certain cancers, Alzheimer’s disease, and anxiety.
More research is necessary; to date, promising studies into the health benefits of ashwagandha have mainly been in animals.
This article looks at the traditional uses of ashwagandha, how to take it, and the evidence behind its possible health benefits and risks.
Ashwagandha is an important herb in Ayurvedic medicine. This is one of the world’s oldest medical systems and one of India’s healthcare systems.
In Ayurvedic medicine, ashwagandha is considered a Rasayana. This means that it helps maintain youth, both mentally and physically.
There is some evidence to suggest that the herb can have neuroprotective and anti-inflammatory effects. Inflammation underpins many health conditions, and reducing inflammation can protect the body against a variety of conditions.
For example, people use ashwagandha to help treat the following:
stress
anxiety
fatigue
pain
skin conditions
diabetes
arthritis
epilepsy
Different treatments make use of different parts of the plant, including the leaves, seeds, and fruit.
Scientific studies have suggested that ashwagandha might be beneficial for a number of conditions.
That said, researchers do not know a lot about how the herb reacts within the human body. Most studies so far have used animal or cell models, meaning that scientists do not know if the same results will occur in humans.
increases muscle mass and strength
Research has shown that ashwagandha may improve body composition and increase 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
boosts testosterone and increase fertility in men
Ashwagandha supplements may have powerful effects on testosterone levels and reproductive health
In one study in 75 infertile men, the group treated with ashwagandha showed increased sperm count and motility.
What’s more, the treatment led to a significant increase in testosterone levels
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
Stress and anxiety
Ashwagandha may have a calming effect on anxiety symptoms when compared with the drug lorazepam, a sedative and anxiety medication.
A 2000 study suggested that the herb had a comparable anxiety-reducing effect with lorazepam, suggesting that ashwagandha might be as effective for reducing anxiety. However, the researchers conducted this study in mice, not humans.
In a 2019 study in humans, researchers found that taking a daily dose of 240 milligrams (mg) of ashwagandha significantly reduced people’s stress levels when compared with a placebo. This included reduced levels of cortisol, which is a stress hormone.
In another 2019 study in humans, taking 250 mg or 600 mg of ashwagandha per day resulted in lower self-reported stress levels, as well as lower cortisol levels.
Although this research is promising, scientists need to collect much more data before recommending the herb to treat anxiety.
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
Also, several human studies have suggested that it can reduce blood sugar levels in both healthy people and those with diabetes
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
In a 2019 study in humans, researchers found that taking a daily dose of 240 milligrams (mg) of ashwagandha significantly reduced people’s stress levels when compared with a placebo. This included reduced levels of cortisol, which is a stress hormone.
In another 2019 study in humans, taking 250 mg or 600 mg of ashwagandha per day resulted in lower self-reported stress levels, as well as lower cortisol levels.
Although this research is promising, scientists need to collect much more data before recommending the herb to treat anxiety.
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
Also, several human studies have suggested that it can reduce blood sugar levels in both healthy people and those with diabetes
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
reduces inflammation
Several animal studies have shown that ashwagandha helps decrease inflammation
Studies in humans have found that it increases the activity of natural killer cells, which are immune cells that fight infection and help you stay healthy
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
Arthritis
Ashwagandha may act as a pain reliever, preventing pain signals from traveling along the central nervous system. It may also have some anti-inflammatory properties.
For this reason, some research has shown it to be effective in treating forms of arthritis, including rheumatoid arthritis.
A small 2015 study in 125 people with joint pain found the herb to have potential as a treatment option for rheumatoid arthritis.
Heart health
Some people use ashwagandha to boost their heart health, including:
lowering high blood pressure
lowering high cholesterol
easing chest pain
preventing heart disease
However, there is little research to support these benefits.
One 2015 study in humans suggested that ashwagandha root extract could enhance a person’s cardiorespiratory endurance, which could improve heart health. However, more research is necessary.
May improve brain function, including memory
Test-tube and animal studies suggest that ashwagandha may mitigate memory and brain function problems caused by injury or disease
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
Alzheimer’s treatment
According to a 2011 review several studies have examined ashwagandha’s ability to slow or prevent loss of brain function in people with neurodegenerative conditions such as Alzheimer’s disease, Huntington’s disease, and Parkinson’s disease.
As these conditions progress, parts of the brain and its connective paths become damaged, which leads to loss of memory and function. This review suggests that when mice and rats receive ashwagandha during the early disease stages, it may be able to offer protection.
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 While controlled human studies have reported less dramatic results, they have observed some impressive improvements in these markers
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
reduces 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.
Studies have shown that ashwagandha may help reduce cortisol levels
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
reduces symptoms of depression
Although it hasn’t been thoroughly studied, a few studies suggest ashwagandha may help alleviate 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.
Cancer
The same 2011 review also describes a few promising studies that found that ashwagandha might be able to stop cell growth in certain cancers. This includes reducing lung tumors in animal studies.
How to take ashwagandha
The dosage of ashwagandha and the way people use it depends on the condition they are hoping to treat. There is no standard dosage based on modern clinical trials.
Different studies have used different dosages. Some research suggests that taking 250–600 mg per day can reduce stress. Other studies have used much higher dosages.
Capsule dosages often contain between 250 and 1,500 mg of ashwagandha. The herb comes in the form of a capsule, powder, and liquid extract.
