Short answer: ashwagandha's strongest evidence is for lowering cortisol and stress, and several trials report modest testosterone effects alongside that. So the honest way to describe it is not that it directly raises testosterone the way a hormone would, but that it works on the stress system that sits upstream of a lot of how men feel. The cortisol story is the reliable one, and it happens to matter more than most people expect.
The cortisol connection, in plain terms
Cortisol is your main stress hormone. Chronically high cortisol, from poor sleep, relentless pressure and no recovery, works against the systems involved in testosterone, energy and body composition. Ashwagandha is an adaptogen with human trial data showing reduced cortisol and lower perceived stress. When the stress load comes down, the systems that testosterone depends on get to work under better conditions. That is the mechanism, and it is why a stress ingredient earns a place in a testosterone formula rather than a sleep one.
A 2019 randomized trial on KSM-66, a branded ashwagandha extract, is the reference many people cite for the stress and hormone effects at a defined dose. The Daily uses KSM-66 at 600 mg, the studied dose, printed on the tin.
Why the branded extract and the dose matter
Ashwagandha is a root with active compounds that vary by how it is grown and extracted. KSM-66 is a standardized, well-studied extract, which is why we use it rather than a generic powder at an unnamed amount. The 2019 trial used a specific dose, and matching that dose is the difference between running the study and merely name-dropping the herb. If you want to see how to check that on any label, we wrote what a clinically studied dose actually means.
The honest caveat about mood
Ashwagandha has an under-discussed downside. At higher or long-continuous dosing, some men report feeling emotionally flat or unmotivated. It is real, it is dose and duration dependent, and almost no testosterone brand will mention it. We think you should know before you start, so we wrote a whole piece on it: ashwagandha and emotional blunting.
Straight answers
Does ashwagandha raise testosterone or just lower cortisol?
The cortisol and stress evidence is the strongest. Modest testosterone effects show up alongside it. Treat the stress mechanism as the main event.
What dose of ashwagandha is effective?
Trials commonly use around 600 mg of a standardized extract like KSM-66, which is what The Daily uses.
Can I take ashwagandha every day forever?
Many people take it daily, but the mood caveat is dose and duration dependent, so it is worth reading the blunting piece and paying attention to how you feel.
The Daily uses KSM-66 ashwagandha at 600 mg as the stress piece of a ten-active formula. See the panel.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.