Ashwagandha KSM-66 — 600mg Extract
Clinically studied KSM-66® ashwagandha — root-only extract standardised to ≥5% withanolides. Cortisol reduction confirmed in 22 gold-standard trials.
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Order dispatched, tracking info sent. Most customers take their first dose the day it arrives.
Research shows it takes ~14 days to anchor a new habit. By now, most customers have found their ideal time of day.
At 8 weeks, customers report the strongest improvements. Consistency is everything with nutritional supplements.
Over 90% of Medibro subscribers are still on the same product at 3 months — the clearest signal a supplement is working.
KSM-66® is the world's most clinically studied ashwagandha root extract, produced by Ixoreal Biomed using a unique green chemistry extraction process. It's standardised to ≥5% withanolides — the active compounds responsible for stress and cortisol reduction.
600mg/day is the dose shown in the landmark 2012 Chandrasekhar trial to reduce serum cortisol by 27.9% and improve quality of life scores significantly vs placebo.
Benefits
- ✓Stress reduction
- ✓Cortisol control
- ✓Sleep quality
- ✓Testosterone support
- ✓Muscle recovery
Complete your stack
✨What customers say
From 20 reviews★ 4.6Customers appreciate the noticeable reduction in stress and anxiety levels, improved sleep quality, and enhanced gym performance, often reporting significant benefits within just a few weeks of use.
Some users experienced drowsiness, particularly when taken during the day, suggesting it may be better suited for evening use for certain individuals.
This product is ideal for those dealing with high stress, anxiety, or sleep issues, including professionals in high-pressure jobs and individuals undergoing therapy or managing hormonal changes.
Customer reviews
- ★★★★★James K.Verified buyer28/04/2026Gym performance improved too
Unexpected benefit: gym lifts went up. The reduction in cortisol helps with recovery. Strength is up, sleep better. Genuinely impressive supplement.
- ★★★★★Priya N.Verified buyer26/04/2026Noticed difference within 2 weeks
I was sceptical — seemed too good to be true. But after 2 weeks of consistent use my stress levels noticeably reduced. I'm calmer during work calls and my sleep has improved. The KSM-66 form is definitely the real deal.
- ★★★★★Helen A.Verified buyer17/04/2026Consistent effects
3 months in. The effects are consistent — not like caffeine where you feel nothing after 2 weeks. Adaptogenic effects appear to build.
- ★★★★★Oliver M.14/04/2026Proper dose, proper quality
Most ashwagandha is dosed too low to do anything. 600mg KSM-66 is what studies use. Finally a supplement that doesn't cut corners on dose.
- ★★★★★Samantha W.Verified buyer18/03/2026Stress completely manageable now
High-pressure corporate job, cortisol through the roof. 8 weeks on this and I genuinely feel calmer. Work stress hasn't changed but my reaction to it has.
- ★★★★★Gary M.01/03/2026Exactly what the research says
I read the studies before buying. KSM-66 clinical trials show real cortisol reduction. This matches those findings in my experience.
- ★★★★★Mark T.Verified buyer20/02/2026Recommend to everyone
Recommended to three colleagues with work stress. All three noticed improvement within 4 weeks. Proper supplement.
- ★★★★★Chris R.Verified buyer26/01/2026Reduced my anxiety considerably
Struggling with general anxiety for years. GP referred me to CBT which helps, but added this and the combination is working really well. Calmer, better sleep, less reactive in stressful situations.
- ★★★☆☆Paul B.03/01/2026Made me a bit drowsy
Good stress reduction but quite sedating for daytime use. Better taken in evening. Might suit others differently.
- ★★★★★Colin W.31/12/2025Body of evidence is real
Pharmacologist here. KSM-66 has the most robust human trial data of any adaptogen. Finally found a brand that uses the proper extract at proper dose.
- ★★★★★Mark J.Verified buyer31/12/2025Best ashwagandha on the market
I've tried Solgar, Natures Best, and a few others. This KSM-66 at 600mg blows them all out of the water. Actually feel the adaptogenic effects — cortisol seems lower, gym performance up slightly, much calmer under pressure.
- ★★★★☆Sophie L.Verified buyer23/12/2025Good stress support
I work in finance and the stress was killing me. This genuinely takes the edge off. Not a miracle cure but a real, noticeable difference. Worth it.
- ★★☆☆☆Hannah D.04/12/2025Made me feel drowsy in day
I know it's supposed to be calming but made me too drowsy during the day. Might work better taken at night. Quality seems fine, just doesn't suit my system.
- ★★★★★George R.Verified buyer25/11/2025Finally slept through the night
Work stress was causing 3am wake-ups. KSM-66 dosing before bed alongside my existing sleep routine and I sleep through. Game changer.
- ★★★★★Rebecca N.Verified buyer18/11/2025Transformed my anxiety
Social anxiety has been a problem for years. This supplement alongside therapy has genuinely reduced my baseline anxiety. Still amazed.
- ★★★★★Louise F.Verified buyer16/09/2025Thyroid anxiety resolved
Subclinical thyroid issues causing anxiety. GP suggested trying ashwagandha alongside standard treatment. This has helped significantly.
- ★★★★★Angela S.Verified buyer18/08/2025Menopause stress support
Perimenopausal and the HPA axis dysregulation is real. This helps moderate the stress response. GP-approved addition to my supplement protocol.
- ★★★★★Maria T.Verified buyer13/08/2025Best adaptogen by far
Tried rhodiola, ginseng, and two ashwagandha brands. This KSM-66 600mg is clearly superior. More relaxed and energy is steadier through the day.
- ★★★★☆Steve H.12/07/2025Good quality, proper dose
600mg KSM-66 is the clinical dose. Most cheap brands give 300mg of inferior extract. This is correctly formulated.
- ★★★★☆Diana P.Verified buyer14/06/2025Really works for stress
Sceptical person here. Tested this for 12 weeks and can confirm my perceived stress is noticeably lower. My partner says I'm calmer too.
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