Ashwagandha (Withania somnifera) Research

Latin Name: Withania somnifera

Family: Solanaceae

Ashwagandha, also called Indian ginseng, has been used to help reduce anxiety, blood sugar levels, and arthritis.

RESEARCH

The listings of research below represent a compilation of scientific articles found on the species, with a very brief overview description of each article/study.  Research found is catalogued by therapeutic action.  This categorized compilation of research articles does not necessarily imply that there are adequate results to demonstrate safe and/or effective human use.

GENERAL

• Natural Medicines (2017). Ashwagandha Monograph.  Retrieved in July, 2016.  Retrieved from www.naturalmedicines.com
• Petersen, D. (2016).  Course Material.  HERB503, Advanced Herbal Materia Medica II.  American College of Healthcare Sciences.  www.achs.edu.
• Mishra, L. C., Singh, B. B., & Dagenais, S. (2000). Scientific basis for the therapeutic use of Withania somnifera (ashwagandha): a review. Alternative medicine review, 5(4), 334-346.
• Singh, N., Bhalla, M., de Jager, P., & Gilca, M. (2011). An overview on ashwagandha: a Rasayana (rejuvenator) of Ayurveda. African Journal of Traditional, Complementary and Alternative Medicines, 8(5S).
• Verma, S. K., & Kumar, A. (2011). Therapeutic uses of Withania somnifera (Ashwagandha) with a note on withanolides and its pharmacological actions. Asian Journal of Pharmaceutical and Clinical Research, 4(1), 1-4.

CONTRAINDICATIONS

• Abortifacient effect: not to be used during pregnancy or lactation (Natural Medicines, 2017).
• May interfere with the following medications: thyroid hormones, diabetics, hypertensives, immune suppressants, anesthesia for surgery, sedatives, and anxiolytic drugs (Natural Medicines, 2017).
• Excessive intake can cause gastric upset (Natural Medicines, 2017).

ANXIOLYTIC

• Participants given a 300 mg of extract from the root of the Ashwagandha had significantly reduced stress compared to placebo.  From:  Chandrasekhar, K., Kapoor, J., & Anishetty, S. (2012). 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 journal of psychological medicine, 34(3), 255.
• In a twelve week clinical trial, ashwagandha significantly reduced anxiety compared to placebo.  From:  Cooley, K., Szczurko, O., Perri, D., Mills, E. J., Bernhardt, B., Zhou, Q., & Seely, D. (2009). Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974. PLoS One, 4(8), e6628.
• In a randomized placebo controlled double blind study of 86 particpants, ashwagandha reduced anxiety symptoms over placebo.  From:  SudKhyati, S., & Anup, B. T. (2013). A randomized double blind placebo controlled study of ashwagandha on generalized anxiety disorder. IntAyurvedic Med J, 1, 1-7.
• In this clinical trial of 98 chronically stressed people, an extract of ashwagandha root and leaf extract resulted in reduced cortosol levels, pulse rate, and blood pressure over 30 and 60 days. Bio-actives in the plant include withanolide glycosides and aglycodes.  From:  Abedon, B., & Ghosal, S. (2008). A standardized Withania somnifera extract significantly reduces stress-related parameters in chronically stressed humans: a double-blind, randomized, placebo-controlled study.
• This double blind study of 52 overweight chronically stressed people demonstrated ashwagandha root extract over 8 weeks had no adverse side effects and reduced stress and food cravings as well  as cortisol levels and body weight.  From:  Choudhary, D., Bhattacharyya, S., & Joshi, K. (2017). Body weight management in adults under chronic stress through treatment with Ashwagandha root extract: a double-blind, randomized, placebo-controlled trial. Journal of evidence-based complementary & alternative medicine, 22(1), 96-106.
• In a review of research, ten herbs offered human trails and demonstrated potential in reducing anxiety by affecting the Gamma-aminobutyric acid (GABA) inhibitory neurotransmitter. These included: kava, valerian, pennywort, hops, chamomile, ginkgo biloba, passionflower, ashwagandha, skullcap, and lemon balm. From: Savage, K., Firth, J., Stough, C., & Sarris, J. (2018). GABA‐modulating phytomedicines for anxiety: A systematic review of preclinical and clinical evidence. Phytotherapy research, 32(1), 3-18.
• In a thorough review of scientific research, the author concluded high quality evidence to support kava, passionflower, and galphimia for anxiety and St. John’s wort and saffron for depression. The author found promising evidence for turmeric for depression, ashwagandha for anxiety and depression, and for ginkgo as an adjunct treatment to schizophrenia. From: Sarris, J. (2018). Herbal medicines in the treatment of psychiatric disorders: 10‐year updated review. Phytotherapy research, 32(7), 1147-1162.

MENTAL DISORDERS

• In a 12 week study of 66 patients with exacerbated symptoms of schizophrenia, an ashwagandha supplement significantly reduced symptoms compared to the placebo with minimal side effects.  From:  Chengappa, K. R., Brar, J. S., Gannon, J. M., & Schlicht, P. J. (2018). Adjunctive Use of a Standardized Extract of Withania somnifera (Ashwagandha) to Treat Symptom Exacerbation in Schizophrenia: A Randomized, Double-Blind, Placebo-Controlled Study. The Journal of clinical psychiatry, 79(5).
• In a study of 30 people with obsessive compulsive disorder, taking an adjunct ashwagandha supplement of 120 mg a day for 6 weeks significantly safely reduced symptoms compared to the placebo.  From:  Jahanbakhsh, S. P., Manteghi, A. A., Emami, S. A., Mahyari, S., Gholampour, B., Mohammadpour, A. H., & Sahebkar, A. (2016). Evaluation of the efficacy of Withania somnifera (Ashwagandha) root extract in patients with obsessive-compulsive disorder: A randomized double-blind placebo-controlled trial. Complementary therapies in medicine, 27, 25-29.

​​​HYPOGLYCEMIC AND HYPOLIPIDAEMIC

• A randomized, double blind, placebo controlled, clinical trial  demonstrated Withania sominfera had a hypoglycemic and hypo-lipidemic effect in patients with drug induced metabolic syndrome from drugs to treat schizophrenia.  Agnihotri, A. P., Sontakke, S. D., Thawani, V. R., Saoji, A., & Goswami, V. S. (2013). Effects of Withania somnifera in patients of schizophrenia: a randomized, double blind, placebo controlled pilot trial study. Indian journal of pharmacology, 45(4), 417-418.
• Ashwagandha extracts taken for 10 days reduced elevated plasma glucose, insulin, and cortisol levels, and alterations in adrenal gland and spleen weights of diabetic animals.  From:  K Thakur, A., Dey, A., S Chatterjee, S., & Kumar, V. (2015). Reverse Ayurvedic pharmacology of Ashwagandha as an adaptogenic anti-diabetic plant: a pilot study. Current Traditional Medicine, 1(1), 51-61.

​​ANTI-INFLAMMATORY

• Ashwagandha possessed anti-inflammatory activity in vitro, possibly related to the alkaloid and withanolide content.  From:  Chandra, S., Chatterjee, P., Dey, P., & Bhattacharya, S. (2012). Evaluation of anti-inflammatory effect of ashwagandha: a preliminary study in vitro. Pharmacognosy Journal, 4(29), 47-49.
• Leaf extracts from ashwagandha and its withaferin constituent strongly inhibited inflammation in vitro.  From:  Kaileh, M., Berghe, W. V., Heyerick, A., Horion, J., Piette, J., Libert, C., … & Haegeman, G. (2007). Withaferin A strongly elicits IκB kinase β hyperphosphorylation concomitant with potent inhibition of its kinase activity. Journal of Biological Chemistry, 282(7), 4253-4264.

​​ARTHRITIS / JOINT PAIN

• Ashwagandha powder and Sidh Makardhwaj reduced rheumatoid arthritis systems in 86 patients with arthritis.  From:  Kumar, G., Srivastava, A., Sharma, S. K., Rao, T. D., & Gupta, Y. K. (2015). Efficacy & safety evaluation of Ayurvedic treatment (Ashwagandha powder & Sidh Makardhwaj) in rheumatoid arthritis patients: a pilot prospective study. The Indian journal of medical research, 141(1), 100.
• In a double blind study of 60 patients with knee joint pain, taking an ashwaganda supplement for 12 weeks was safe and effective.  From:  Ramakanth, G. S., Kumar, C. U., Kishan, P. V., Usharani, P., Fatima, N., Pingali, U., … & Divyya, S. (2016). Efficacy and tolerability of an aqueous extract of roots and leaves of Withania somnifera in a randomized, double-blind, placebo-controlled clinical study in patients with knee joint pain and discomfort. J Ayurveda Integr Med, 7, 151-7.
• W. somnifera root powder reduced inflammation, pain, and temperature in gouty arthritic paw without causing gastric damage. From:  Rasool, M., & Varalakshmi, P. (2006). Suppressive effect of Withania somnifera root powder on experimental gouty arthritis: an in vivo and in vitro study. Chemico-biological interactions, 164(3), 174-180.

​ANTIBACTERIAL

• Ashwagandha plant root and leaves possessed strong antibacterial activity against a range of bacteria in vitro.   From:  Owais, M., Sharad, K. S., Shehbaz, A., & Saleemuddin, M. (2005). Antibacterial efficacy of Withania somnifera (ashwagandha) an indigenous medicinal plant against experimental murine salmonellosis. Phytomedicine, 12(3), 229-235.

​ANTICANCER / ANTITUMOR

• W. somnifera and its isolated withaferin A constituent from the root showed both antitumor and radio-sensitizing effects in experimental tumors in vivo.  From:  Devi, P. U. (1996). Withania somnifera Dunal (Ashwagandha): potential plant source of a promising drug for cancer chemotherapy and radiosensitization. Indian Journal of Experimental Biology, 34(10), 927-932.

THYROID

• In a study of 50 patients with hypothyroid symptoms, an ashwagandha supplement taken for 8 weeks helped to normalize serum thyroid hormones compared to the placebo.  From:  Sharma, A. K., Basu, I., & Singh, S. (2018). Efficacy and safety of ashwagandha root extract in subclinical hypothyroid patients: a double-blind, randomized placebo-controlled trial. The Journal of Alternative and Complementary Medicine, 24(3), 243-248.
• This article discussed the use of ashwagandha to help improve thyroid function.  From:  Peters, S. (2018). Withania somnifera: An ancient botanical with thyroid enhancing properties. Journal of the Australian Traditional-Medicine Society, 24(2), 122.

COGNITION

• Withania somnifera (ashwagandha root), Semecarpus anacardium (marking-nut stem bark), Embelia ribes (false black pepper root), Tinospora cordifolia (heart-leaved moonseed stem), Ficus religiosa (sacred fig stem bark) and Nardostachys jatamansi (spikenard rhizome) showed the most potent acetylcholinesterase inhibitory activity in vitro and maybe useful to treat improved cognition and Alzheimer’s.  From:  Vinutha, B., Prashanth, D., Salma, K., Sreeja, S. L., Pratiti, D., Padmaja, R., … & Deepak, M. (2007). Screening of selected Indian medicinal plants for acetylcholinesterase inhibitory activity. Journal of ethnopharmacology, 109(2), 359-363.
• This paper reviews ashwagandha in vitro and in vivo studies on neurodegenerative diseases such as Alzheimer’s and spinal chord injury.  From:  Kuboyama, T., Tohda, C., & Komatsu, K. (2014). Effects of Ashwagandha (roots of Withania somnifera) on neurodegenerative diseases. Biological and Pharmaceutical Bulletin, 37(6), 892-897.

​​FERTILITY

• Withania somnifera reduced oxidative stress and improved sperm count and motility in 75 men with fertility issues.  From:  Ahmad, M. K., Mahdi, A. A., Shukla, K. K., Islam, N., Rajender, S., Madhukar, D., … & Ahmad, S. (2010). Withania somnifera improves semen quality by regulating reproductive hormone levels and oxidative stress in seminal plasma of infertile males. Fertility and sterility, 94(3), 989-996.
• Forty-six male patients with oligospermia taking ashwagandha for three times a day for 90 days showed a 167% increase in sperm count, 53% increase in semen volume , and 57% increase in sperm motility.  From:  Ambiye, V. R., Langade, D., Dongre, S., Aptikar, P., Kulkarni, M., & Dongre, A. (2013). Clinical evaluation of the spermatogenic activity of the root extract of Ashwagandha (Withania somnifera) in oligospermic males: a pilot study. Evidence-Based Complementary and Alternative Medicine, 2013.

MEN’S HEALTH

• In a 16 week study with 43 overweight men ages 40-70, taking an ashwagandha supplement increased testosterone levels compared to the placebo.  There were not significant differences in cortisol or estradiol levels.  From:  Lopresti, A. L., Drummond, P. D., & Smith, S. J. (2019). A randomized, double-blind, placebo-controlled, crossover study examining the hormonal and vitality effects of ashwagandha (Withania somnifera) in aging, overweight males. American journal of men’s health, 13(2), 1557988319835985.

ATHLETIC PERFORMANCE

• In a double blind placebo controlled study with 50 athletic adults, taking an ashwagandha supplement for 12 weeks improved cardio-respiratory endurance.  From:  Choudhary, B., Shetty, A., & Langade, D. G. (2015). Efficacy of Ashwagandha (Withania somnifera [L.] Dunal) in improving cardiorespiratory endurance in healthy athletic adults. Ayu, 36(1), 63.

MENOPAUSE

• In a study of 117 menopausal women, an ayurvedic blend of Tinospora Cardifolia, Asparagus racemosus, Withania somnifera and Commiphora mukul taken twice daily for two weeks significantly reduced symptoms compared to the placebo. From:  Steels, E., Steele, M., Harold, M., Adams, L., & Coulson, S. (2018). A double-blind, randomized, placebo-controlled trial evaluating safety and efficacy of an ayurvedic botanical formulation in reducing menopausal symptoms in otherwise healthy women. Journal of Herbal Medicine, 11, 30-35.

IMMUNOMODULATORY

• In animal studies, treatment with ashwagandha resulted in a significant increase in hemoglobin concentration, red blood cell count, white blood cell count, platelet count, and body weight.  From:  Ziauddin, M., Phansalkar, N., Patki, P., Diwanay, S., & Patwardhan, B. (1996). Studies on the immunomodulatory effects of Ashwagandha. Journal of ethnopharmacology, 50(2), 69-76.

By: Kathy Sadowski

Updated: 7/12/19