Ashwagandha: Which Extract Actually Works?
Ashwagandha is everywhere right now. But not all extracts are equal — most products use inferior forms. Here's how to find one that has actual clinical backing.
Why ashwagandha extract quality matters enormously
Ashwagandha root powder is cheap to manufacture, but it has wildly variable withanolide content — the compounds actually responsible for its effects. Without standardisation, you could be taking a product with minimal active content. The difference between a good extract and a poor one is not marginal — it's the difference between clinical relevance and an expensive placebo.
KSM-66 vs Sensoril: the two you can trust
KSM-66
KSM-66 is a full-spectrum root extract standardised to at least 5% withanolides. It is the most clinically tested ashwagandha extract, appearing in the majority of positive human randomised controlled trials. Studies have used 300–600mg daily with effects seen within 8 weeks. If you can only remember one name, remember this one.
Sensoril
Sensoril uses both root and leaf material and is standardised to 10% withanolides at a typically lower dose (125–250mg). Well-studied and particularly cited in cognitive and stress research. Both KSM-66 and Sensoril are legitimate — preference depends on the dose and study you're targeting.
Red flags to avoid
Products listing only "ashwagandha root powder" with no standardisation
Blends where ashwagandha is combined with many other herbs at low doses
No withanolide percentage stated on the label
Very cheap products (under £5) — unlikely to contain quality extract
Safety note
Ashwagandha is generally well tolerated but should be avoided in pregnancy (may stimulate contractions) and used cautiously in people on thyroid medication (it can raise T3/T4 levels). Rare cases of liver injury have been reported at very high doses — stick to label recommendations.
Our top pick: Myvitamins KSM-66 Ashwagandha
Myvitamins uses the genuine KSM-66 extract at the 600mg dose used in the best clinical trials. At around £16 for 60 capsules, it's good value vs premium specialist brands that charge £30+ for the same extract.
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