April 2019 Issue
Ask the Expert: Ashwagandha Supplementation
By Toby Amidor, MS, RD, CDN
Today’s Dietitian
Vol. 21, No. 4, P. 8
Q: Some of my clients are thinking about taking ashwagandha supplements for conditions such as inflammation and daily stress. What exactly is ashwagandha, what are its purported benefits, and is there scientific merit to these claims?
A: Withania somnifera, which goes by the common names ashwagandha, Indian ginseng, or winter cherry, is a common herb used in Indian Ayurvedic medicine, typically to improve energy levels, overall health, longevity, and a variety of other conditions. Some research on ashwagandha has been conducted on animals or in vitro, but few human studies have been done, resulting in limited evidence of anti-inflammatory and antistress benefits.
Claims
Ashwagandha means “the smell of a horse” in Sanskrit (the root is known for smelling like a horse) and is traditionally said to confer “the power of a horse” upon consumption. It’s used as a Rasayana, a type of herb believed to promote physical and mental youthfulness and expand happiness, and typically is given to small children and middle-aged and older adults to increase longevity. Many Rasayana herbs, including ashwagandha, are adaptogens, purported to help the body cope with daily stress and adverse effects of physical, chemical, and biological agents.1 Ashwagandha also is used to reduce pain; treat rheumatoid arthritis, diabetes, and epilepsy; enhance the function of the brain and nervous system; improve memory; and promote sexual and reproductive balance.
There are more than 35 chemical constituents of ashwagandha that have been isolated, and many have been studied, including bioactive components such as alkaloids, steroidal lactones, saponins, and withanolides.2 It’s also a good source of iron.
Research
Ashwagandha is touted for its anti-inflammatory properties to provide relief for those with rheumatoid arthritis. In a three-day study published in the Indian Journal of Experimental Biology, researchers gave powdered ashwagandha root to rats orally one hour before administering an inflammation-promoting injection. Compared with placebo, ashwagandha considerably reduced inflammation based on serum protein markers in the blood.3 Another study published in the same journal looked at the anti-inflammatory effects of ashwagandha also in rats. Based on radiological exam, rats that were orally administered powdered ashwagandha root for 15 days showed significant reductions in paw swelling and bone degeneration changes compared with rats given a hydrocortisone placebo.4
Antistress effects of ashwagandha were evaluated in rats swimming in cold water (ie, exposed to a stressor). Rats given an alcohol extract from defatted ashwagandha seeds dissolved in saline could tolerate the stressor longer, demonstrating a swimming time double that of mice administered saline solution alone.5 A 2012 prospective, randomized, double-blinded, placebo-controlled study of 64 human subjects with a history of chronic stress demonstrated substantially lower serum cortisol levels in those who took one capsule of ashwagandha root extract twice a day for 60 days compared with placebo.6
While no side effects were reported in the latter study, short-term side effects of ashwagandha supplementation can include drowsiness, upper gastrointestinal discomfort, and loose stool; therefore, it’s considered possibly safe when taken short term. Long-term safety of ashwagandha supplementation is unknown for all populations, but any ashwagandha use is contraindicated during pregnancy, as it may induce abortion, and while using sedatives, as ashwagandha may increase their effects.
Ashwagandha typically is available in powder form made from the root of the plant, as well as in teas and capsules combined with numerous other herbs touting benefits such as sustained energy, thyroid support, and detoxification/cleanse.
Bottom Line
While there’s some evidence to support ashwagandha’s possible antistress and anti-inflammatory benefits, more research is needed. No safe or effective dosage has been established, and ashwagandha tends to be added to supplements that already contain vitamins, minerals, and other herbs that can be contraindicated for certain health conditions and medications. If clients insist on taking ashwagandha, they should be warned about medication and condition interactions and instructed to stick to short-term use.
— Toby Amidor, MS, RD, CDN, is the founder of Toby Amidor Nutrition (http://tobyamidornutrition.com) and a Wall Street Journal best-selling author. Her four cookbooks are Smart Meal Prep for Beginners, The Easy 5-Ingredient Healthy Cookbook, The Healthy Meal Prep Cookbook, and The Greek Yogurt Kitchen. She’s a nutrition expert for FoodNetwork.com and a contributor to US News Eat + Run, Muscle&Fitness.com, and MensJournal.com.
References
1. Singh N, Bhalla M, de Jager P, Gilca M. An overview on ashwagandha: a Rasayana (rejuvenator) of Ayurveda. Afr J Tradit Complement Altern Med. 2011;8(5 Suppl):208-213.
2. Mishra LC, Singh BB, Dagenais S. Scientific basis for the therapeutic use of Withania somnifera (ashwagandha): a review. Altern Med Rev. 2000;5(4):334-346.
3. Anbalagan K, Sadique J. Influence of an Indian medicine (ashwagandha) on acute-phase reactants in inflammation. Indian J Exp Biol. 1981;19(3):245-249.
4. Begum VH, Sadique J. Long term effect of herbal drug Withania somnifera on adjuvant induced arthritis in rats. Indian J Exp Biol. 1988;26(11):877-882.
5. Archana R, Namasivayam A. Antistressor effect of Withania somnifera. J Ethnopharmacol. 1999;64(1):91-93.
6. Chandrasekhar K, Kapoor J, Anishetty S. A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adults. Indian J Psychol Med. 2012;34(3):255-262.