Most clinical trials use between 300 mg and 600 mg of ashwagandha root extract per day, split into one or two doses. That range has shown measurable benefits for stress, sleep, and physical performance across dozens of studies. But the right amount for you depends on what form you’re taking, because not all ashwagandha products are created equal.
Why the “mg” on the Label Can Be Misleading
Ashwagandha supplements come in two very different forms: raw root powder and concentrated extracts. A 1,000 mg capsule of plain root powder is not the same as a 300 mg capsule of a standardized extract. The extract has been processed to concentrate the active compounds (called withanolides), so you need far fewer milligrams to get the same effect.
Clinical trials have used extracts standardized to contain anywhere from 1.5% to 35% withanolides. A highly concentrated extract like Shoden, which contains 35% withanolides, was studied at just 120 mg per day (two 60 mg capsules). Meanwhile, a root extract standardized to around 5% withanolides, like KSM-66, is typically studied at 300 to 600 mg per day. The optimal percentage of withanolides isn’t settled, but the takeaway is clear: check the label for the type of extract and its withanolide content, not just the total milligrams.
Dosages Used in Research, by Goal
Stress and Sleep
Studies on stress and sleep quality have used a wide range of doses depending on the extract. In one trial, 150 adults with sleep problems took 120 mg per day of a root-and-leaf extract (Shoden) for six weeks and saw improvements. Other trials testing KSM-66 and Sensoril used higher milligram amounts because those extracts are less concentrated. For general stress relief, 300 to 600 mg of a root extract daily is the most commonly studied range.
Athletic Performance and Strength
For muscle strength, recovery, and cardiorespiratory fitness, research points to 300 to 500 mg of aqueous root extract taken twice daily for 8 to 12 weeks. In one eight-week trial, participants taking 300 mg twice daily (600 mg total) nearly doubled their bench press strength gains compared to placebo. A separate trial found that 500 mg of aqueous root extract improved both upper and lower body strength over 12 weeks. Some studies have also reported meaningful increases in testosterone levels in men at these doses.
How Long Before You Notice Anything
Ashwagandha is not something you feel after one dose. In clinical trials, the earliest measurable benefits appeared within about two weeks, but most improvements built gradually over 6 to 10 weeks. The majority of studies ran for 8 to 12 weeks total. If you’ve been taking it consistently for two months and notice nothing, the dose or extract may not be working for you. Starting and stopping after a few days won’t give you useful information.
When and How to Take It
Taking ashwagandha with food is the simplest approach. Some people get mild stomach discomfort on an empty stomach, and meals that include some fat may support absorption. Beyond that, there’s no strong evidence that morning versus evening matters, though people taking it primarily for sleep often prefer an evening dose. Consistency matters more than timing. Pick a mealtime you won’t skip and stick with it.
Picking the Right Product
The three branded extracts you’ll see most often are KSM-66, Sensoril, and Shoden. All three have been used in clinical research, but they differ in which plant parts they use and how concentrated they are. KSM-66 uses root only and is typically dosed at 300 to 600 mg per day. Sensoril uses root and leaf. Shoden is the most concentrated, standardized to 35% withanolides, and is dosed much lower at around 120 mg per day.
If your supplement doesn’t specify a branded extract or withanolide percentage, it’s harder to know what you’re actually getting. Generic “ashwagandha root powder” capsules often contain 1,000 to 2,000 mg of unprocessed powder, which delivers far fewer active compounds per milligram than a concentrated extract. That doesn’t mean they’re useless, but comparing them milligram-to-milligram with extracts is like comparing fresh garlic cloves to garlic oil capsules.
Side Effects and Upper Limits
There is no officially established upper limit for ashwagandha. Most clinical trials have used doses up to 600 mg of concentrated extract daily for up to 12 weeks without serious adverse effects. The most common complaints are mild: stomach upset, nausea, or loose stools, which tend to improve when taken with food or at a lower dose.
Ashwagandha can affect thyroid hormone levels, so people with thyroid conditions should be cautious. It may also interact with sedatives, immunosuppressants, and medications for blood sugar or blood pressure, since it has mild effects in all of those areas. Pregnant individuals should avoid it entirely, as traditional use and limited safety data both point against it during pregnancy.
A Practical Starting Point
If you’re buying a standardized root extract like KSM-66, 300 mg once or twice daily with food is a well-supported starting dose. If you’re using a higher-concentration extract like Shoden, 120 mg daily is the studied amount. For plain root powder capsules without a specified withanolide content, the research is less precise, but doses in the range of 1,000 to 2,000 mg daily are common in traditional use. Give it at least 6 to 8 weeks of consistent daily use before judging whether it’s doing anything for you.