Ashwagandha (Withania somnifera) has been used in Ayurvedic medicine for centuries, but what makes it relevant to modern women over 50 is not its tradition — it is the growing body of clinical research supporting specific, measurable effects on stress, cognition and physical wellbeing.
This article focuses specifically on KSM-66, the most studied form of ashwagandha, and what the research shows for women in the post-50 demographic.
What is KSM-66?
KSM-66 is a patented, high-concentration ashwagandha root extract produced by Ixoreal Biomed. Unlike full-plant or leaf extracts, it is standardised to a minimum 5% withanolides (the active compounds) from root only — the form with the longest history of use and the most clinical data behind it.
It has been studied in over 20 randomised controlled trials, making it one of the most thoroughly researched botanical ingredients in the supplement industry.
What the research shows
Stress and cortisol reduction
The most robust evidence for KSM-66 is in stress reduction. A double-blind RCT published in the Indian Journal of Psychological Medicine found that 300mg of KSM-66 twice daily for 60 days produced a statistically significant reduction in perceived stress scores and serum cortisol levels compared to placebo. [source]
Why this matters for women over 50: elevated cortisol is both a cause and consequence of the perimenopausal transition. Reducing cortisol has downstream effects on sleep, mood, cognitive function and even body composition.
Memory and cognitive function
A 2017 RCT in the Journal of Dietary Supplements found significant improvements in immediate and general memory, executive function, sustained attention and information-processing speed in adults taking KSM-66 versus placebo over 8 weeks. [source]
The mechanism is likely multi-pathway: cortisol reduction (which removes a direct inhibitor of hippocampal function), antioxidant effects, and possible cholinergic activity.
Sleep quality
A 2019 RCT found that KSM-66 significantly improved sleep quality, sleep onset latency, total sleep time and sleep efficiency compared to placebo in adults with insomnia. [source] Given the central role of sleep disruption in menopause brain fog, this is a meaningful secondary benefit.
What the research doesn't show
Being honest about limitations matters:
- Most trials are relatively short (60–90 days) — long-term effects are less well characterised.
- Effect sizes are meaningful but not dramatic — ashwagandha is not a pharmaceutical-grade intervention.
- Trials are predominantly in mixed-sex populations or in stressed adults generally; specific data on post-menopausal women is limited.
- The cognitive improvements are most pronounced in individuals with high baseline stress — if your stress levels are low, the cognitive benefit may be smaller.
Safety and interactions
KSM-66 is generally well-tolerated. Reported side effects are mild (occasional GI discomfort, drowsiness). However:
- Thyroid medication: Ashwagandha can affect thyroid hormone levels. If you are on levothyroxine or other thyroid medication, discuss with your GP before use.
- Sedatives: Additive sedative effects are possible with prescription sleep aids or benzodiazepines.
- Autoimmune conditions: Ashwagandha may stimulate immune activity — not appropriate for those on immunosuppressants.
- Pregnancy: Not recommended during pregnancy.
Recommended dose: The doses used in the research above are 300–600mg of KSM-66 root extract per day, taken consistently for at least 8 weeks before evaluating results.