What does ashwagandha do?

When you're stressed — from work, bad sleep, overtraining — your body pumps out a hormone called cortisol. A little cortisol is fine. Too much, for too long, and it starts causing problems: poor sleep, low energy, weight gain, and even lower testosterone in men.

Ashwagandha helps turn down that stress response. In clinical trials, people who took it saw their cortisol drop by about 28% over 60 days. That's a meaningful shift — the kind you'd actually feel.

What can you expect?

• Less stress and anxiety — you feel calmer, more resilient to daily pressure
• Better sleep — fall asleep faster, wake up less during the night
• More energy — not a stimulant buzz, just steadier energy through the day
• Higher testosterone (men) — studies show a 17% increase in men with high stress
• Better workouts — improved recovery and stamina in active people

How to take it

How long to take it: Most people do 2–3 months on, then take a month off. Some take it year-round. Both approaches are fine.

When to avoid it: If you're on thyroid medication, talk to your doctor first — ashwagandha can affect thyroid levels. Also skip it if you're pregnant or breastfeeding.

Which form to buy?

There are two main branded extracts you'll see. Here's the simple breakdown:

If you're not sure, go with KSM-66. It's the most researched, easiest to find, and works well for most goals.

Frequently Asked Questions

How it works in your body

Your body has a built-in stress system called the HPA axis. When it's overactive — from long work hours, poor sleep, or constant pressure — it keeps pumping out cortisol. Ashwagandha's active compounds (called withanolides) help dial this system back down to normal.

The downstream effects: when cortisol drops, sleep improves, testosterone is no longer suppressed, and your overall recovery gets better. It also interacts with GABA receptors in your brain, which is why it helps with anxiety and falling asleep.

What the studies show

• Cortisol: 28% reduction in morning cortisol after 60 days at 600 mg/day (vs 8% in placebo)
• Stress: 30–40% improvement in perceived stress scores across multiple trials
• Testosterone: 17% increase in men after 90 days (most notable in men with high stress or fertility concerns)
• Sleep: Significantly faster time to fall asleep and fewer nighttime wake-ups
• Exercise: Improved VO2 max and muscle recovery in athletes

Side effects & safety

Ashwagandha is well-tolerated by most people, but there are a few things to be aware of:

• Drowsiness — It has a calming effect. Some people feel sleepy, especially at 600 mg or above. If this happens, shift your dose to the evening.
• Stomach upset — Nausea or discomfort can happen if taken on an empty stomach. Always take it with food.
• Thyroid changes — Ashwagandha can raise T3 and T4 levels. If you take thyroid medication (like levothyroxine), monitor your thyroid panel closely and space the two by at least 2 hours.
• Headache — Uncommon but reported, usually in the first week. Tends to resolve on its own.
• Hormonal sensitivity — Because it can affect testosterone and cortisol, avoid it if you have hormone-sensitive conditions unless cleared by a doctor.

Who should skip it: Pregnant or breastfeeding women, people on immunosuppressants, and anyone with autoimmune conditions (ashwagandha can stimulate the immune system). If you're on any prescription medication, check with your doctor before starting.

Which labs to check

If you want to track your response properly, get these tested before you start and again at 90 days:

• Morning cortisol (taken 8–9 AM) — the main marker ashwagandha targets
• Total testosterone — to see if the cortisol reduction is freeing up testosterone
• Thyroid panel (TSH, Free T3, Free T4) — ashwagandha can shift thyroid levels

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