KSM-66® Ashwagandha (Withania somnifera root extract)
KSM-66® is a specific branded form of Withania somnifera (ashwagandha) root extract, manufactured by Ixoreal Biomed (Hyderabad, India) under a patented milk-extraction process. It is the most-cited standardised ashwagandha extract in the modern human-trial literature and the branded form whose trial portfolio underpins most ashwagandha supplements sold in the UK. KSM-66 standardises ≥5% withanolides by HPLC and uses root-only material (no leaf). There are no UK-authorised food-supplement health claims for ashwagandha; trial framing on KSM-66 surfaces must remain descriptive.
Camden's own editorial team graded each health claim below on the strength of the published evidence, under the CEGA method. How we grade the evidence, and where the method does not yet reach. See the grade beside every condition.
- Class
- Botanical
- Typical daily dose
- Trial outcomes for KSM-66 cluster at 300 mg twice daily (600 mg/day) or 600 mg once daily over 8–12 weeks. UK retail products supply KSM-66 at 250–600 mg per capsule. There is no UK consensus dose because there is no authorised UK health claim. Dose ranges are descriptive of trial conditions only.
- Top use evidence
- Limited
On this page
- What it is
- At a glance
- What people use it for
- How it works
- Common myths
- Common online questions
- The official position
- What the guidance says
- Camden's evidence review
- Safety, interactions & who should avoid it
- How to take it
- How to spot quality
- Commonly combined with
- Related ingredients
- How this entry was researched
What it is
KSM-66® (a registered trademark of Ixoreal Biomed Pvt. Ltd., Hyderabad, India) is a specific branded form of Withania somnifera (ashwagandha) root extract. The brand name covers a patented manufacturing process that uses root material only (no leaf) and a milk-extraction step, yielding a full-spectrum extract standardised to ≥5% withanolides as measured by HPLC. The nominal manufacturing pathway runs ~14 months from raw root to finished extract.
KSM-66 is the most-cited standardised ashwagandha form in the modern human-trial literature. Trial dosing across the published portfolio sits between 250 mg/day and 600 mg/day, with most outcome trials at 300 mg twice daily or 600 mg once daily for 8–12 weeks. The trial portfolio reports signals on perceived stress markers (cortisol, PSS), sleep quality (PSQI), exercise outcomes (VO₂max, strength, recovery), and cognitive markers in older adults — but UK food-supplement health claims for ashwagandha (and therefore for KSM-66) are not authorised. Botanicals sit on the EFSA on-hold list pending claim-specific evaluation.
From a commercial-supplement standpoint, KSM-66 is one of three standardised branded ashwagandha forms (alongside Sensoril by Natreon and Shoden by Arjuna Natural). The forms are not interchangeable in trial-evidence terms because the trial portfolio attached to each is specific to that form's extraction pattern and standardisation. A generic X:1 root-extract or unstandardised root powder is not a like-for-like substitute, even at the same milligram weight.
Naming "KSM-66®" on a UK food-supplement label requires a documented licence chain from Ixoreal Biomed (or its territorial distributor) routed to the supplier. Naming the brand without the chain is a trademark-infringement risk under TMA 1994 s.10. Camden Medicals' NB-463 and NB-537 use KSM-66 sourced via Troo Health Care; Camden's upstream paper trail to Ixoreal is verbally confirmed but the documented chain is in progress (see TODO #29 — sub-tier GMP cert pack — in fera_activation_runbook.md / supplier_improvement_register).
At a glance
- A specific patented branded form of Withania somnifera (ashwagandha) root extract — KSM-66® is a registered trademark of Ixoreal Biomed (Hyderabad).
- Standardised to ≥5% withanolides by HPLC; root-only material (no leaf); manufactured under a 14-month milk-extraction process.
- The most-cited standardised ashwagandha form in the modern human-trial literature — trial signals reported across stress markers, sleep quality, exercise outcomes, and cognition at 250–600 mg/day for 8–12 weeks.
- No UK-authorised food-supplement health claims for ashwagandha (botanicals are on the EFSA on-hold list). The trial-portfolio framing on KSM-66 must remain descriptive — "trials report…" rather than asserting effect.
- Naming "KSM-66®" on a UK label requires a documented licence chain from Ixoreal Biomed — naming without the chain is a TM infringement risk.
- Pregnancy: avoid. Thyroid disease: discuss with prescriber. Discontinue and seek advice if symptoms of liver irritation develop.
What people use it for
Adults curious about ashwagandha supplementation and choosing between branded and generic forms
KSM-66 carries the largest published trial portfolio of any standardised ashwagandha form. Trial signals on perceived stress markers (cortisol, PSS) and sleep quality (PSQI) sit within the 250–600 mg/day, 8–12 week trial window. UK food-supplement health claims for ashwagandha are not authorised; the trial-evidence framing is descriptive only. Generic X:1 root extracts at the same milligram are not trial-evidenced equivalents.
Some evidenceLimitedAdults considering ashwagandha for diagnosed anxiety or depression
Ashwagandha (including KSM-66) is not a UK-recognised pathway for diagnosed mood or anxiety disorders. UK NHS / NICE pathways for anxiety and depression apply (CBT, SSRIs, talking therapies). Self-supplementation with a botanical is not the appropriate pathway for a diagnosed mental-health condition.
InsufficientAdults considering ashwagandha as part of an exercise / strength routine
The KSM-66 trial portfolio includes exercise-outcome trials in resistance-trained adults reporting signals on VO₂max, strength, and recovery markers at 300–600 mg/day for 8–12 weeks. Trial sizes are moderate; effects are mid-range. UK food-supplement claims for sports outcomes are not authorised on ashwagandha. The framing is exploratory, not performance-guaranteed.
Some evidenceLimitedAdults choosing between KSM-66, Sensoril, Shoden, or generic ashwagandha extract
KSM-66 (Ixoreal Biomed) is root-only and trial-portfolio-deepest. Sensoril (Natreon) is root + leaf with higher withanolide standardisation (≥10%). Shoden (Arjuna Natural) is root + leaf with very high withanolide content (≥35%) at lower dose. The three are not interchangeable in trial terms — each form's evidence base is form-specific. Generic X:1 or unstandardised root powder lacks the trial-portfolio that the branded forms carry.
Some evidenceLimited
How it works
The mechanism framing for KSM-66 is the herb-level mechanism of Withania somnifera (HPA-axis modulation, GABA-ergic trial signals, cortisol-marker effects in stress trials). The branded form does not have a unique mechanism distinct from the herb; what is unique is the standardisation and trial portfolio attached to that standardisation. UK food-supplement claim wording for the herb is not authorised, so mechanism framing on KSM-66 surfaces stays descriptive of trial endpoints rather than asserting in-vivo effect.
Common myths
Myth"All ashwagandha is the same — KSM-66 is just marketing"
RealityThe trial portfolio attached to KSM-66 is specific to KSM-66 manufacturing pattern (root-only, 14-month milk-extraction, ≥5% withanolides standardised). A generic X:1 root extract or unstandardised root powder is not trial-evidenced as a like-for-like substitute. The price premium reflects manufacturing process, brand licence, and trial-portfolio substantiation. Generic isn''t necessarily ineffective; it''s just not what the trial literature is reporting on.
Myth"Higher milligrams = better effect"
RealityKSM-66 trial outcomes cluster at 300–600 mg/day. Above that, the trial evidence thins rapidly. Higher milligrams of unstandardised root powder do not approximate higher doses of KSM-66 — the standardisation matters disproportionately.
Myth"A 5% withanolide-standardised extract is the same as KSM-66"
Reality≥5% withanolides is one of several criteria that define KSM-66; the others are root-only material, the patented 14-month milk-extraction process, Ixoreal Biomed manufacturing, and the documented licence chain. A non-KSM-66 product labelled as "5% withanolides" meets one of those criteria; the trial portfolio attached to KSM-66 is not transferable.
Myth"KSM-66 is approved by Ixoreal Biomed therefore it has UK health claims"
RealityBrand approval at the manufacturer level is not a UK food-supplement health-claim authorisation. UK health claims for ashwagandha are on the EFSA on-hold list for botanicals; no claims are currently permitted on UK food-supplement labels. Trial-evidence wording must remain descriptive on Camden surfaces.
Common online questions
Synthesised from the questions UK shoppers most often ask online about KSM-66® Ashwagandha (Withania somnifera root extract). Each answer is editorial and links to its evidence in the Sources list below.
Why is KSM-66 sold at higher prices than generic ashwagandha?
The price difference reflects three things. First, KSM-66 is manufactured under a patented 14-month milk-extraction process and standardised to ≥5% withanolides by HPLC — both cost more than commodity X:1 root powder. Second, Ixoreal Biomed licences the brand under documented chain-of-custody terms; suppliers pay a brand-licence fee that flows through to retail price. Third, the trial portfolio attached to KSM-66 is the largest published for any standardised ashwagandha form, and the brand premium reflects the substantiation that gives the product. Generic X:1 extracts at the same milligram weight cost less because they have none of those layers.
KSM-66 vs Sensoril vs Shoden — which is "best"?
None is universally "best"; the three are different formulations and trial portfolios. KSM-66 (Ixoreal Biomed) is root-only, ≥5% withanolides, with the deepest published trial portfolio on stress, sleep, exercise, and cognition. Sensoril (Natreon) is root + leaf, higher-standardised (≥10% withanolides), and has its own trial portfolio. Shoden (Arjuna Natural) is also root + leaf, very high standardisation (≥35% withanolides), at a lower dose. The trial evidence attached to each is form-specific — they are not interchangeable at equal milligrams. Choose by matching your goal to the form''s trial portfolio rather than defaulting to the cheapest standardisation percentage.
Is the milk-extraction process vegan-incompatible?
The milk-extraction step in KSM-66 manufacturing uses milk as a processing aid — it is consumed in the extraction and the final powder does not contain milk solids. Ixoreal Biomed publishes a vegan-suitable assessment of the finished extract. Camden Medicals lists NB-463 (KSM-66 capsules) and NB-537 (Shilajit with KSM-66) as vegan-suitable on the back of that supplier substantiation. If strict-vegan exclusion of any animal-derived processing aid is your standard, the milk-extraction step is a consideration to be aware of even though the end product carries no milk traces.
I had ashwagandha and felt sleepy / nauseous / dizzy — should I be worried?
Mild GI complaints (nausea, abdominal discomfort, loose stools) are common and usually settle when taken with food. Drowsiness is reported and is the basis of the evening-dose recommendation when sleep-quality is the goal. If you develop symptoms suggestive of liver irritation — yellowing of the skin or whites of the eyes (jaundice), dark urine, right-upper-quadrant pain — discontinue immediately and seek medical advice.
Can I take KSM-66 if I am pregnant, breastfeeding, or trying to conceive?
No. Ashwagandha is contraindicated in pregnancy because of traditional-use abortifacient framing and absence of human safety data in pregnancy. Avoid in lactation (no human safety data). If you are trying to conceive, talk to your GP before supplementing — ashwagandha-androgen-axis interactions in male fertility trials are reported but not a basis for taking the herb without clinical guidance.
Can I take KSM-66 with thyroid medication?
Talk to your prescriber first. Ashwagandha trial signals on thyroid-axis markers (TSH, T3, T4) are reported, and the herb can theoretically alter levothyroxine dosing requirements. If you take levothyroxine, carbimazole, or have any diagnosed thyroid disease, discuss ashwagandha with your GP or endocrinologist before supplementing. The conservative position in the absence of trial-grade interaction data is to avoid self-initiation while on thyroid medication.
⚖️ The official position
What may lawfully be claimed about KSM-66® Ashwagandha (Withania somnifera root extract) in Great Britain. This is a regulatory position, not an evidence grade.
No health claim is authorised for KSM-66® Ashwagandha (Withania somnifera root extract) in Great Britain.
This page describes the evidence and online discussion without making a claim.
UK regulatory landscape
UK regulatory tier: Food supplement
UK regulatory rules evolve. This summary is editorial — businesses should consult regulatory counsel; consumers should consult their pharmacist or GP.
🩺 What the guidance says
What UK and international health bodies say. Guidance leads; Camden’s own evidence review follows below.
NHSConditional
Herbal medicines and supplements (NHS)
The NHS advises that food supplements and herbal products are not held to the same proven safety and quality standards as licensed medicines unless registered, can interact with prescription medicines, and should be discussed with a doctor or pharmacist. KSM-66 is an ashwagandha extract; herbal extracts can interact with medicines and are not suitable for everyone (for example in pregnancy or with thyroid or liver conditions).
GOVUKNot assessed
FSA call for evidence on ashwagandha (FSA / COT review)
The UK Food Standards Agency has run a call for evidence and a Committee on Toxicity review of ashwagandha safety, reflecting reports of possible liver, thyroid and other effects; no safe intake level has been set. As KSM-66 is an ashwagandha extract, this regulatory-safety review applies to it.
EFSANot assessed
EFSA Article 13 claims — not authorised (ashwagandha / KSM-66)
Health claims for ashwagandha / KSM-66 are on hold or have not been authorised in the Article 13 process. No health claim is permitted for ashwagandha / KSM-66 as a food supplement.
GB-NHCNot assessed
GB Nutrition and Health Claims register — ashwagandha / KSM-66 (no authorised claim)
The Great Britain Nutrition and Health Claims register holds no authorised health claim for ashwagandha / KSM-66. No health claim may be made for ashwagandha / KSM-66 sold in Great Britain.
🔬 Camden’s evidence review
The research Camden reviewed, graded on its strength. This is our own appraisal — it sits beneath the official guidance above, never above it.
Perceived stress and salivary cortisol — short-term
EvidencelimitedTrials of KSM-66 300 mg twice daily or 600 mg once daily over 8–12 weeks have reported reductions in perceived stress scores (PSS) and morning salivary cortisol in adults reporting chronic stress. Trial sizes range from small to moderate (n ≈ 50–200); funding is heterogeneous (some industry-linked, some independent). The framing on Camden surfaces is "trials report" rather than effect-asserting.
Sleep quality (PSQI) — short-term
EvidencelimitedTrials of KSM-66 300 mg twice daily for 6–8 weeks have reported improvements in PSQI total score in adults reporting non-restorative sleep. Effects are modest; the trial framing does not claim treatment for diagnosed insomnia. UK NHS / NICE pathways for diagnosed sleep disorders apply.
Exercise outcomes — strength, VO₂max, recovery
EvidencelimitedTrials of KSM-66 300–600 mg/day in resistance-trained adults over 8–12 weeks have reported signals on VO₂max, 1RM strength, and creatine-kinase recovery markers. Effect sizes are modest. UK food-supplement claims for sports outcomes are not authorised on ashwagandha.
Cognitive function in older adults — short-term
EvidencelimitedA small set of trials of KSM-66 300 mg twice daily over 8 weeks in adults 50+ reported signals on memory and executive-function markers. Trial sizes are small; replication is limited. UK NHS / NICE pathways for diagnosed cognitive decline apply.
Hepatotoxicity safety
EvidenceinsufficientKSM-66 inherits the herb-level caution. The UK position is that consumers should discontinue and seek medical advice if symptoms suggestive of liver irritation (jaundice, dark urine, right-upper-quadrant pain) develop.
Safety
KSM-66 Ashwagandha is generally well-tolerated in healthy adults at 250–600 mg/day over 8–12-week trial windows. Discontinue and seek medical advice if symptoms of liver irritation develop. No UK food-supplement health claims are permitted. Pregnancy, lactation, paediatric use, thyroid disease, autoimmune disease, active oncology: avoid or defer to your prescriber.
Talk to your pharmacist or GP first if you:
- You are pregnant, breastfeeding, or trying to conceive — ashwagandha is contraindicated in pregnancy.
- You are under 18.
- You have any thyroid disease (hypothyroidism, hyperthyroidism, Graves, Hashimoto) or take thyroid medication (levothyroxine, carbimazole).
- You take immunosuppressants or have any autoimmune disease.
- You have liver disease or take hepatotoxic medication.
- You take sedatives, benzodiazepines, or other CNS depressants — additive sedation is plausible.
- You take any prescribed medication and are unsure of botanical interactions.
Common side effects: Mild GI complaints (nausea, abdominal discomfort, loose stools) — particularly without food. Drowsiness is reported and is the basis of evening-dose convention.
Pregnancy and breastfeeding
Avoid. Ashwagandha (including KSM-66) is contraindicated in pregnancy. Traditional-use framing of abortifacient activity; absence of human safety data in pregnancy.
Avoid. No human lactation safety data.
Talk to your GP, midwife, or pharmacist before starting any supplement during pregnancy or breastfeeding.
More clinical detail (for clinicians and informed readers)
Contraindications
- Pregnancy — avoid (traditional-use abortifacient framing; no human safety data).
- Lactation — avoid (no human safety data).
- Paediatric use — avoid.
- Active autoimmune disease (Hashimoto thyroiditis, lupus, MS, RA) — defer to prescriber given immune-modulation framing in the trial literature.
- Liver disease — avoid (hepatotoxicity caution).
- Active cancer or cancer treatment — defer to oncology team.
Drug interactions
- Thyroid medication (levothyroxine, carbimazole) — theoretical interaction; trial signals on thyroid-axis markers reported. Discuss with prescriber before initiating.
- Immunosuppressants (ciclosporin, tacrolimus, mycophenolate) — theoretical interaction; defer to prescriber.
- Sedatives, benzodiazepines, Z-drugs, alcohol — additive sedation plausible.
- Diabetes medication — theoretical glucose-lowering interaction; monitor.
- Hepatotoxic medication (high-dose paracetamol regular use, certain statins) — additive risk; defer to prescriber.
This is not an exhaustive list. Always tell your prescriber and pharmacist about every supplement you take.
Common side effects
- Mild GI complaints — nausea, abdominal discomfort, loose stools; reduce by taking with food.
- Drowsiness — basis of evening-dose convention when sleep is the goal.
Rare side effects
- Headache.
- Allergic reaction (nightshade family — Solanaceae).
- Liver irritation symptoms (jaundice, dark urine, RUQ pain) — discontinue immediately and seek medical advice.
How to take it
- Typical supplemental range
- Trial outcomes for KSM-66 cluster at 300 mg twice daily (600 mg/day) or 600 mg once daily over 8–12 weeks. UK retail products supply KSM-66 at 250–600 mg per capsule. There is no UK consensus dose because there is no authorised UK health claim. Dose ranges are descriptive of trial conditions only.
- Timing
- Daily, with food (reduces GI tolerance issues). Evening dosing is conventional when sleep-quality is the goal; morning or split-dosing is conventional for stress-marker goals. Trial endpoints emerge over 8–12 weeks.
How to spot quality
Look for
- KSM-66® brand name with ® mark on the label or product description.
- Standardisation declared (≥5% withanolides by HPLC).
- Root-only material declared (no leaf — KSM-66-defining criterion).
- Manufacturer named (Ixoreal Biomed).
- Licence chain on supplier file (or supplier confirms upstream licence is in place).
- CoA per batch (declared on request).
- Heavy-metal screening disclosed.
- Pregnancy / thyroid / hepatotoxicity cautions on the PDP and on-pack.
- No anxiety, depression, mood, sleep-treatment, or sports-performance effect-claim wording — botanicals are EFSA-on-hold.
Red flags
- No KSM-66® brand mark — generic "ashwagandha extract" with implied trial-portfolio framing is misleading.
- KSM-66® named on label without supplier licence chain — TM infringement risk.
- Withanolide standardisation declared as percentage range without HPLC method named.
- Root + leaf material under KSM-66 branding — KSM-66 is root-only by definition.
- Anxiety, depression, mood, sleep-treatment, or sports-performance claim wording.
- No hepatotoxicity / pregnancy / thyroid caution.
Commonly combined with
Other ingredients that share a biological pathway, cofactor relationship, or evidence-backed protocol with this one. Mechanisms below cite primary physiology — not folk pairing. Doses are literature ranges, not recommendations. Talk to your pharmacist or GP before changing your stack, especially if you take prescription medication.
Rhodiola (Rhodiola rosea)
Limited evidenceKSM-66 + Rhodiola is a conventional adaptogen stack pattern — separate trial portfolios; combination evidence sparse.
KSM-66 (HPA-axis trial framing) and Rhodiola rosea (energy / fatigue trial framing) are conventionally combined in adaptogen stacks targeting stress + energy goal-pairs. Trial portfolios attached to each are separate; combination outcome trials are sparse. UK food-supplement claims for either are not authorised.
Evidence: Conventional in adaptogen stacks. Combination evidence sparse.
Doses studied: KSM-66 300–600 mg + Rhodiola 200–400 mg daily.
Vitamin B6
Insufficient evidenceB6 is the regulatory anchor for any psychological-function or fatigue framing on a multi-active KSM-66 SKU — the EFSA-permitted claim attaches to B6, not to KSM-66.
Vitamin B6 (pyridoxine) carries authorised EFSA health claims including normal psychological function, normal nervous-system function, and normal energy-yielding metabolism. In a multi-active SKU containing KSM-66 and B6, regulatory framing for psychological-function or fatigue attaches to B6, not to KSM-66. This is a regulatory pairing pattern, not a trial-validated synergy.
Evidence: EFSA-authorised claims for B6 are settled regulatory positions. Botanicals (including KSM-66) sit on the EFSA on-hold list.
Doses studied: B6 1.4 mg minimum (100% NRV) to anchor a permitted claim alongside KSM-66 300–600 mg.
Magnesium
Limited evidenceKSM-66 + Magnesium is conventional in stress / sleep stacks — magnesium contributes the EFSA-authorised muscle / nervous-system anchors.
Magnesium contributes EFSA-authorised health claims (normal muscle function, normal psychological function, reduction of tiredness and fatigue, normal protein synthesis). KSM-66 contributes the ashwagandha trial-evidence layer (descriptive only on UK labels). The pairing is conventional in stress / sleep stacks; the regulatory anchor for any energy / fatigue / muscle framing attaches to magnesium.
Evidence: Mechanism is well-described. Combination outcome trials with KSM-66 specifically are sparse.
Doses studied: Magnesium 100–375 mg (elemental) + KSM-66 300–600 mg daily.
Sources
Numbered references cited above plus general authoritative reading. Citations in the body link to the matching number here.
How to read these sources:
- Tier 1 (UK authoritative): NHS, NICE, BNF, EFSA, FSA, GB NHC Register, SACN, MHRA.
- Tier 2 (primary literature): peer-reviewed RCTs cited by PMID.
- Tier 3 (mechanistic): in-vitro / animal-model literature — interpret with caveat.
How this entry was researched
Authoritative sources consulted:
- NHS — herbal medicines overview
- GB Nutrition and Health Claims Register (gov.uk)
- UK FSA — Committee on Toxicity (CoT) — opinions and statements
- EFSA — Health claims (Article 13.1, on-hold botanicals)
Sources listed are those consulted by the Afera editorial team. Readers should verify against current authoritative sources.