Ashwagandha
The most evidence-backed adaptogen. Lowers cortisol, blunts stress reactivity, improves sleep, and modestly raises testosterone in men.
Multiple human RCTs support 20–30% cortisol reduction, improvements in PSS (perceived stress scale) and sleep quality indices, modest testosterone elevation in men, and improvements in V̇O₂max in trained subjects. Anxiety reduction: 2–4 weeks. Sleep improvement: 2–6 weeks. Hormonal effects: 8–12 weeks.
Ashwagandha (Withania somnifera) is an Ayurvedic root used for thousands of years and now one of the most rigorously studied herbal extracts. It works through the HPA axis — modulating cortisol output, dampening the stress response, and supporting GABA signalling. The result is something that feels less like a stimulant or a sedative and more like a slow widening of your stress bandwidth. After 2–4 weeks most users report that everyday irritations bother them less, sleep is steadier, and recovery from hard exercise improves. Men typically see a modest testosterone bump (5–15% on average); women see improvements in stress, sleep, and DHEA-S.
- Form
- KSM-66 (full-spectrum root extract, standardised to 5% withanolides) — the most-studied form. Balanced, can be taken AM or PM. Sensoril (root + leaf, standardised to 10% withanolides) — more sedating, lean to PM use. Avoid unstandardised raw-powder products — potency varies wildly.
- Dose
- KSM-66: 600 mg daily, taken once or split AM/PM. Sensoril: 250–500 mg daily, evening preferred.
- Timing
- AM, PM, or split. KSM-66 is flexible. Sensoril leans PM. With or without food.
- Schedule
- Cycle 8 weeks on, 2 weeks off. Some people do fine continuously, but periodic breaks prevent receptor desensitisation and give you a clearer read on whether it's actually still helping. Not a forever-supplement for most.
- Side effects
- Mild GI upset in some. Drowsiness — if it's too sedating, take only AM. Paradoxically stimulating in a small minority (insomnia if taken PM). Very rarely, mild liver enzyme elevation — discontinue if jaundice or right-upper-quadrant pain appears.
- Interactions
- Thyroid medication — ashwagandha mildly raises T3/T4 and can stack with levothyroxine, pushing you hyperthyroid. Sedatives and benzodiazepines (additive). Immunosuppressants (ashwagandha is mildly immunostimulant). Diabetes medications (mild glucose-lowering effect).
- Contraindications
- Hyperthyroidism — ashwagandha raises thyroid hormone and can worsen it. Pregnancy — abortifacient in traditional use, avoid. Autoimmune conditions (Hashimoto's, RA, MS, lupus) — immune-stimulating effect can flare them. Caution with active liver disease. Caution if you take any of: thyroid hormone, immunosuppressants, sedatives.
- Lab markers
- Not typically monitored. If tracking stress objectively: morning cortisol, DHEA-S, and a salivary cortisol curve before and after 8 weeks. For men: total + free testosterone, SHBG. For caution: TSH + free T4 / T3 before starting if any thyroid history.
- Food sources
- Not present in everyday food — this is a concentrated herbal extract.
Pairs with
Magnesium glycinate (synergistic for sleep and HPA calming). Rhodiola (complementary stress response — rhodiola for acute morning stress, ashwagandha for chronic stress and sleep). L-Theanine (additive anxiolytic). Tongkat ali in male testosterone-support stacks.
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