What is ashwagandha and what does it do?
Ashwagandha is a plant used in traditional Ayurvedic and Unani medicine. It is commonly promoted for sleep, stress, and anxiety as well as cognitive function. Ashwagandha is also known as Withania somnifera, Indian ginseng, and winter cherry.
Ashwagandha supplements usually contain extracts made from the plant’s roots or from the roots and leaves.
Does ashwagandha work?
The health effects of ashwagandha extracts have not been thoroughly studied, but here’s what we have learned from the research so far.
Stress and anxiety
Ashwagandha extracts might help reduce stress and anxiety. In several studies, people who took ashwagandha for 6 to 8 weeks reported that they felt less stress and anxiety as well as less fatigue and sleeplessness. Ashwagandha also lowered stress hormone levels. In some studies, ashwagandha appeared to be more effective when taken at doses of 500 to 600 milligrams (mg) per day compared with lower doses.
Sleep
Results from a few small studies suggest that ashwagandha extracts might improve sleep. In these studies, people who had trouble sleeping and took ashwagandha reported that they fell asleep faster, slept longer, and woke up less often during the night. Overall, the benefits for sleep were small, but ashwagandha seemed most helpful when taken at doses of 600 mg per day or more for at least 8 weeks.
Is ashwagandha safe?
In the studies described above, there were no safety concerns when people used ashwagandha extracts for up to about 3 months. Common side effects of ashwagandha are usually mild and include upset stomach, loose stools, nausea, and feeling drowsy. However, it’s not clear whether ashwagandha is safe to use for longer periods of time.
Ashwagandha extracts have been linked to liver injury in some people, but more research is needed to understand this potential concern.
A few studies show that ashwagandha may affect how your thyroid gland works. Therefore, ashwagandha might interact with thyroid medications. Ashwagandha might also interact with diabetes and blood pressure medications, sedatives, and medications that suppress your immune system.
Ashwagandha may not be safe for people with prostate cancer or those who are pregnant or breastfeeding.
Summary
Several studies have shown that ashwagandha might reduce stress and anxiety. It might also improve how well and how long you sleep. However, more research is needed to confirm these findings. It’s also important to note that studies have used many different types and doses of ashwagandha extracts and most were conducted as part of traditional Ayurvedic or Unani medicine.
Ashwagandha appears to be safe for up to 3 months of use, but it’s not clear if ashwagandha is safe to use for longer periods of time. Ashwagandha might cause liver problems and affect how your thyroid gland works. In addition, it might not be safe for people with prostate cancer or those who are pregnant or breastfeeding.
Disclaimer
This fact sheet by the National Institutes of Health (NIH) Office of Dietary Supplements (ODS) provides information that should not take the place of medical advice. We encourage you to talk to your health care providers (doctor, registered dietitian, pharmacist, etc.) about your interest in, questions about, or use of dietary supplements and what may be best for your overall health. Any mention in this publication of a specific product or service, or recommendation from an organization or professional society, does not represent an endorsement by ODS of that product, service, or expert advice.
Glossary
- adverse event
- An unwanted medical problem that occurs during treatment. Adverse events may be unrelated to the treatment or they may be caused by the therapy or procedure. For example, an adverse event may be caused by the toxic effects of a particular drug or dietary supplement or by an interaction with another therapy. Also called adverse effect and side effect.
- Ayurvedic
- A system of medicine that originated in India several thousand years ago. Complex herbal-mineral combinations play key roles in Ayurvedic medicine, and other approaches such as diet and lifestyle modifications are also used. Also called Ayurveda.
- cancer
- A group of diseases in which cells divide abnormally and without control, and spread to nearby tissues and other parts of the body. Without treatment, cancer can stop organs from working normally, damage body systems, and cause the patient to die. Cancer may be caused by multiple factors, such as radiation, sunlight, tobacco, certain viruses, and poisonous chemicals; however, the cause of many cancers is unknown.
- cognitive function
- Mental awareness and judgment.
- diabetes
- A disease in which blood sugar (glucose) levels are high because the body is unable to use glucose properly. Diabetes occurs when the body does not make enough insulin, which helps the cells use glucose, or when the body no longer responds to insulin.
- dose
- The amount of medicine or other substance taken at one time or over a specific period of time.
- extract
- A substance made by soaking an herb in a liquid that removes specific types of chemicals. The liquid can be used as is or evaporated to make a concentrate or a dry extract for use in capsules or tablets.
- fatigue
- Extreme tiredness and an inability to function due to lack of energy.
- gland
- A small organ that makes and releases a substance such as sweat, tears, saliva, milk, a hormone, or substances that aid in digestion.
- hormone
- A group of chemicals made by glands in the body. Hormones circulate in the bloodstream and control the actions of certain cells or organs. Some hormones can also be manufactured.
- immune system
- A group of organs and cells that defends the body against infection, disease, and altered (mutated) cells. It includes the thymus, spleen, lymphatic system (lymph nodes and lymph vessels), bone marrow, tonsils, and white blood cells.
- interaction
- A change in the way a dietary supplement acts in the body when taken with certain other supplements, medicines, or foods, or when taken with certain medical conditions. Interactions may cause the dietary supplement to be more or less effective, or cause effects on the body that are not expected.
- liver
- A large organ located in the right upper abdomen. It stores nutrients that come from food, makes chemicals needed by the body, and breaks down some medicines and harmful substances so they can be removed from the body.
- milligram
- mg. A measure of weight. It is a metric unit of mass equal to 0.001 gram (it weighs 28,000 times less than an ounce).
- nausea
- The uneasy feeling of having an urge to throw up (vomit).
- prostate cancer
- Uncontrolled growth of abnormal cells in the prostate (a gland in the male reproductive system found below the bladder and in front of the rectum). Prostate cancer usually occurs in older men.
- root
- A part of a plant that is below ground.
- sedative
- A drug or other substance that helps cause relaxation, calmness, and sleepiness.
- stool
- The waste matter passed in a bowel movement; feces.
- supplement
- A nutrient that may be added to the diet to increase the intake of that nutrient. Sometimes used to mean dietary supplement.
- thyroid
- A gland located in the front of the neck, below the larynx (Adam’s apple). The thyroid makes hormones that circulate in the bloodstream and affect brain development, metabolism, weight, breathing, heart rate, blood pressure, nervous system functions, body temperature, muscle strength, skin dryness, menstrual cycles, and cholesterol levels.
Updated:
December 4, 2023
