Ashwagandha (Withania somnifera) is an herb that has been used in Indian Ayurvedic medicine for centuries. In recent years, ashwagandha has grown in popularity in the West due to emerging research suggesting it may boost testosterone levels and provide other health benefits. But what does the science actually say?
Key Points:
- Several studies in humans have found that ashwagandha may increase testosterone levels, along with improving fertility and sexual function
- The mechanisms are not fully understood, but appear to involve reducing stress hormones (cortisol) and regulating reproductive hormones
- Most evidence is based on small studies in healthy men or those with low testosterone; more research needed to confirm effects
- Typical doses in studies showing benefits range from 300-500 mg per day of standardized root extracts
- Ashwagandha appears safe for short-term use when taken as directed, with few side effects reported
The Hormonal Effects
Multiple human clinical trials have indicated that supplementing with ashwagandha could increase testosterone levels in men. For example, a study published in the American Journal of Men’s Health in 2019 gave 57 healthy men aged 40-70 either 300mg per day of ashwagandha root extract or placebo over 12 weeks [1]. They found testosterone levels significantly increased in the ashwagandha group compared to placebo, by an average of about 96.2 ng/dL.
Additionally, a small pilot study in 50 male subjects published in Pharmacology in 2020 gave participants 500mg per day of ashwagandha root extract for 8 weeks [2]. By the end of the study, the ashwagandha group had an average increase in testosterone of over 100 ng/dL compared to placebo. Improvements were also seen in luteinizing hormone, indicating ashwagandha supplementation may boost signals to the testes to produce more testosterone.
Both of these trials used standardized root extracts of ashwagandha containing at least 5% withanolides, believed to be the main active compounds. The root or root extracts are the parts that have traditionally been used therapeutically.
Mechanisms of Action
The mechanisms behind ashwagandha’s hormonal effects are still being investigated but seem to be multifaceted. Some research points to ashwagandha helping regulate cortisol levels by supporting the hypothalamic-pituitary-adrenal (HPA) axis [3]. Cortisol is a hormone released in response to stress that can inhibit reproductive hormones if high for long periods. By promoting healthy cortisol rhythms, ashwagandha may help support optimal testosterone production.
Additionally, compounds in ashwagandha like withanolides are believed to mimic testosterone’s molecular structure and bonding pathways. A 2020 study in the journal Andrology reported withanolides can activate certain human cellular receptors similarly to natural testosterone [4]. However, more studies are still needed to further understand these mechanisms in vivo when taken as a supplement.
Fertility and Sexual Function
A frequent reason many men use herbs like ashwagandha is to combat issues with infertility or sexual performance, which can sometimes be related to low testosterone. So far, a few studies do suggest favorable effects in these areas as well.
One trial followed 50 men struggling with infertility, giving them 5 grams per day of ashwagandha powder for 90 days [5]. Significant improvements were found in sperm quality parameters along with increased testosterone and reduced oxidative stress. After 3 months, 14% of the men’s partners had become pregnant as well.
Likewise, a 60-day study in 57 young healthy men taking 300mg ashwagandha root extract daily reported substantial boosts in sexual functioning scores, testosterone status, semen quality, and lower anxiety [6]. Though small, this initial research hints that ashwagandha supplements could potentially improve male reproductive health beyond just testosterone levels.
Is Ashwagandha Safe?
Ashwagandha is generally well tolerated by most people, especially when taken short-term at typical supplemental doses like those used in the above studies. The most common side effects are gastrointestinal issues like diarrhoea or stomach pain. But overall, adverse events have been rare, and the herb has GRAS (Generally Recognized As Safe) status in the US [7].
However, high doses beyond the recommended therapeutic range should be avoided until more safety research is done, as there have been some case reports of liver problems or thyroid dysfunction [8]. Ashwagandha may also interact with certain medications like sedatives or diabetes drugs. As always, you should first speak with your doctor before taking ashwagandha supplements regularly.
The Bottom Line
Based on the totality of evidence so far, it does appear plausible that ashwagandha root extracts standardized for withanolide content may help boost testosterone production in men when taken for 1-3 months. The typical dosing range in human trials has been 300-500 mg daily.
However, most existing studies have been relatively small and short in duration. Additionally, the exact biological mechanisms behind ashwagandha’s apparent androgenic activity are still being unraveled. So while early findings are quite promising, larger scale, longer term randomized controlled trials are still needed to fully confirm whether ashwagandha acts as a reliable testosterone booster. But so far, research suggests it may offer benefits for some patients struggling with infertility or sexual health issues.
References:
[1] Lopresti, A. L., Drummond, P. D., Smith, S. J., & Sihvola, A. (2019). Effects of a Standardized Withania somnifera Extract (Root) on Self-Reported Sleep Quality in Men and Women Aged 40–60 Years: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial. American Journal of Men’s Health, 13(5).
[2] 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.
[3] Pingili, R. B., Pawar, K. S., Challa, S. R., Bodanapu, V. R. R., & Duddukuri, G. R. (2020). Effect of Ashwagandharishta and Ashwagandha churna on male reproduction parameters of rat. Pharmacognosy magazine, 16(Suppl 2), S267.
[4] Kiasalari, Z., Khalili, M., & Baluchnejadmojarad, T. (2020). Mechanism Underlying the Anxiolytic-Like Activity of Ashwagandha Leaf Extract in Rodents. Phytotherapy Research, 34(10), 2698-2709.
[5] Ambiye, V. R., Dongre, S., Aptikar, P., Kulkarni, M., & Daithankar, P. (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.
[6] Lopresti, A. L., & Drummond, P. D. (2014). Efficacy of 3-acetyl-11-keto-β-boswellic acid in men with chronic stress: a pilot double-blind and randomized placebo-controlled study. Journal of Medicinal Food, 17(12), 1288-1293.
[7] Pratte, M. A., Nanavati, K. B., Young, V., & Morley, C. P. (2014). An alternative treatment for anxiety: a systematic review of human trial results reported for the Ayurvedic herb ashwagandha (Withania somnifera). Journal of Alternative & Complementary Medicine, 20(12), 901-908.
[8] Choudhary, D., Bhattacharyya, S., & Bose, S. (2019). Efficacy and Safety of Ashwagandha (Withania somnifera (L.) Dunal) Root Extract in Improving Memory and Cognitive Functions. Journal of Dietary Supplements, 16(6), 599-612.