Ashwagandha
Adaptogenic herb that lowers cortisol and raises testosterone in stressed men.
What is Ashwagandha?
Ashwagandha is an adaptogenic herb used in Ayurvedic medicine for centuries. The active compounds, withanolides, are found in the root. KSM-66 and Sensoril are standardised root extracts used in most clinical studies: these are meaningfully different from cheap, unstandardised ashwagandha powder.
What does the evidence say?
A 2019 randomised controlled trial by Lopresti et al. in Medicine found KSM-66 at 600mg/day significantly increased testosterone by an average of 14.7% and DHEA-S by 18% compared to placebo over 8 weeks. A 2012 study by Chandrasekhar et al. found 300mg of root extract twice daily reduced cortisol by 27.9% and self-reported stress by 44% compared to placebo. A 2015 study by Wankhede et al. showed improvements in muscle recovery and strength alongside testosterone increases in resistance-trained men.
Good evidence from several studies, but with some limitations in size, duration, or methodology.
Dosage guide
| Effective dose | 300–600mg of standardised root extract per day |
| Maximum dose | 600mg/day (clinical studies use this dose; higher has not been well studied) |
| Timing | Can be split into two doses. Some people find it mildly sedating and prefer it in the evening. |
Best form to buy
KSM-66 or Sensoril, both are patented, standardised extracts with the most clinical evidence. Generic ashwagandha root powder is inconsistent and usually lower potency.
Who benefits most
Men under chronic stress (which suppresses testosterone via elevated cortisol), men with poor sleep, and those looking for a natural testosterone support without hormonal side effects.
Side effects and safety
Generally well tolerated. Can cause drowsiness in some people. Rare reports of thyroid hormone changes: relevant if you have an existing thyroid condition. Should be avoided during pregnancy.
“The cortisol-lowering effect is real and that alone justifies it for most modern men. The testosterone bump is modest but consistent in the trials. Buy KSM-66 specifically, the cheap stuff is a waste of money.”