Ashwagandha is a nontoxic herb gaining attention in the U.S. for its ability to modulate stress and anxiety. The herb is an important part of centuries-old Ayurveda, the traditional system of medicine in India. It is used to treat various conditions, such as rheumatism and insomnia.
“[Its] physiologic effects… are interrelated,” says Andrea Fossati, M.D., an integrative healthcare specialist in Vermont. “For example, less stress equals lower cortisol levels, which equals better blood sugar control.”
Still, many clinical trials have tested the herbal substance on a relatively small number of participants. Further and more expansive studies are needed to establish ashwagandha’s claimed benefits, especially long-term.
What Is Ashwagandha?
Ashwagandha is part of a class of plants called adaptogens known for their health benefits when ingested as teas, powders, tinctures and supplements, or in their raw forms.
Also known as Indian ginseng, winter cherry or by its scientific name Withania somnifera, ashwagandha is a herbal shrub whose roots and berries are used for medicinal properties.
7 Health Benefits of Ashwagandha
Research on ashwagandha continues to evolve as scientists worldwide study its efficacy against a variety of ailments.
Here are a few science-backed benefits of ashwagandha.
- Relieves Stress and Anxiety
Ashwagandha is perhaps best known for its stress-relieving properties. Several studies highlight this advantage, observing ashwagandha’s ability to significantly decrease participants’ stress and anxiety levels.
One particular study indicated that ashwagandha could also benefit sleep quality—researchers confirmed participants slept much better with doses of the herb than placebo doses.
- Lowers Blood Sugar and Fat
A couple of small clinical studies found ashwagandha to help reduce blood glucose levels and triglycerides (the most common type of fat in the blood). One study likened ashwagandha’s blood sugar-lowering effects to those of medications prescribed for type 2 diabetes.
- Increases Muscle and Strength
Researchers continue to study ashwagandha’s efficacy in improving strength and muscle size. One study found participants experienced increased speed and strength. Another study observed increased muscle power, alongside a lower body fat percentage and reduced cholesterol levels when ashwagandha was consumed. Some participants also experienced better sleep, but this study did not compare ashwagandha consumption against a placebo.
Ashwagandha treatments produced positive results in another study conducted solely with male participants. Compared to the placebo group, men who received ashwagandha saw significant gains in muscle strength (measured using a bench press and leg extension exercises) and muscle size in their arms and chests and a significant reduction in body fat percentage post-workout muscle damage.
- Improves Sexual Function in Women
At least one clinical study indicates ashwagandha can benefit women experiencing sexual dysfunction. The administration of ashwagandha resulted in significant improvements in arousal, lubrication, orgasm and satisfaction, as self-reported by the participants. It also significantly improved the number of successful sexual encounters and improved metrics of distress around their sex lives and sexuality.
- Boosts Fertility and Testosterone Levels in Men
Ashwagandha may also provide reproductive benefits for men. Administering ashwagandha to infertile men has improved sperm quality significantly by rebalancing reproductive hormone levels. After one study, 14% of the male patients’ partners became pregnant.
In a stress-related ashwagandha study, researchers found the herb increased testosterone levels in male but not female participants. Another study testing ashwagandha’s effect on muscle strength in men also measured a significant increase in testosterone.
- Sharpens Focus and Memory
Ashwagandha may help improve cognition, memory and the ability to perform motor responses after instruction. Small studies have found that, compared to a placebo, ashwagandha significantly improved participants’ reaction times during cognition and psychomotor tests (which measure the ability to respond to instructions and perform an indicated action).
One study even found that ashwagandha significantly improved participants’ attention spans and their immediate and general memory across a variety of tests.
- Supports Heart Health
At least two studies have shown that ashwagandha can increase VO2 max levels, which is the maximum amount of oxygen you take in a while physically exerting yourself. These levels measure cardiorespiratory endurance—how well the heart and lungs deliver oxygen to muscles during physical activity. Thus, higher VO2 max levels can indicate a healthy heart that performs well under those circumstances.
This one study’s results may not apply universally since it was conducted with healthy, athletic adults exclusively as opposed to a more diverse group of participants.
Potential Risks and Side Effects of Ashwagandha
Ashwagandha is a safe and nontoxic plant, but there are a few factors to consider before adding it to your diet.
Do you take other medications? It’s good to let your doctor(s) know if you want to add something new to your health routine, including ashwagandha. If you’re already taking other medications, ashwagandha may enhance or weaken their effects.
Are there other conditions to consider? Ashwagandha may be unsafe if you are pregnant, breastfeeding, immunocompromised, soon undergoing surgery or have a thyroid condition. It’s also worth noting that some people who are allergic to nightshades or have certain grass allergies don’t tolerate ashwagandha well. If any of these situations apply to you, talk to your doctor or an integrative health specialist to determine whether it’s safe for you to take ashwagandha.
What dosage should I take? Experts say that bodies may not absorb all of a 300-milligram dose of ashwagandha. Larger doses may even trigger unwanted side effects, such as vomiting and diarrhea. Instead, take smaller doses more frequently to benefit most from its balancing effects.
Where did this ashwagandha come from? Always check the source of your herbs, especially if you’re buying supplement capsules. Start by asking staff members at natural foods or supplements stores for recommendations. If they say any brand will work, do your research on each company’s certifications, testing practices and product standards. You especially want to check for the presence of any heavy metals, including arsenic, cadmium, lead and mercury, in their products. Exposure to these metals can damage the liver, kidneys, central nervous system, immune system and reproductive system.
How to Take Ashwagandha
Ashwagandha roots and berries can be consumed for their medical properties, but typically, you find ashwagandha in supplement capsules or tablets, powder, tincture and tea form.
Emily Clairmont, a registered dietitian at the University of Vermont Medical Center in Burlington, Vermont, recommends starting with an ashwagandha tea to introduce the herb into your diet gently and contribute to your hydration as well—a crucial factor to overall health.
If you want to get more creative, add the raw form of ashwagandha or an ashwagandha powder ( ashwagandha churna) directly to your food. For example, you can mix the powder into nut butter, granola, smoothies or overnight oats. Just don’t expose it to high heat, Clairmont says, which would cancel out the herb’s therapeutic benefits and possibly even render it carcinogenic. Instead, keep it over medium heat or toss it into your food toward the end of your food preparation.