Ingredient
Moderate evidenceAshwagandha
Also known as: KSM-66, Sensoril, Withania somnifera
The best-studied adaptogen — real evidence for stress, with modest effects on recovery.
What it is
Ashwagandha is a herb used in traditional medicine and now one of the most-studied adaptogens. Quality products use standardised extracts such as KSM-66 or Sensoril, which guarantee a consistent level of the active withanolides rather than relying on vague raw-root amounts.
How it works
The strongest evidence is for reducing stress and anxiety markers, including lowering cortisol in stressed individuals. There is weaker, more mixed evidence for modest improvements in sleep, recovery and testosterone. It is a supportive ingredient for stress and wellbeing rather than a dramatic performance enhancer.
Effective dose
Look for a standardised extract: roughly 300 to 600mg per day of KSM-66 is the most commonly studied. The standardisation matters more than the headline milligrams, because raw-root products vary wildly in potency.
Safety and upper limit
Ashwagandha is generally well tolerated short-term. There have been rare reports of liver issues, and it can interact with thyroid, sedative and immune-related medications, and is not advised in pregnancy. Anyone on medication or with a health condition should check with a clinician first.
Where you find it
Hormone-support and testosterone-support products, stress and sleep formulas.
Top Hormone Support picks
The highest-scoring products in the category where Ashwagandha matters most.
Frequently asked
How much ashwagandha should I take?
Around 300 to 600mg per day of a standardised extract such as KSM-66. Standardisation matters more than the raw milligram figure.
Does ashwagandha boost testosterone?
The evidence is modest and mixed. Its strongest, best-supported effect is reducing stress and cortisol, with smaller possible effects on testosterone and recovery.
Is ashwagandha safe?
It is generally well tolerated short-term, but there are rare liver reports and medication interactions. Check with a clinician if you take medication or have a health condition.
Related guides
This page is educational and not medical advice. Doses are general guidance from the published research, not a personal prescription. Before starting any supplement that could affect a medical condition or interact with medication, speak to a qualified clinician.