New clinical trials published this year add to evidence that ashwagandha may help with sleep, though researchers stress that the herb is not risk-free and should be used with care.

In an eight-week randomised trial of 200 adults with poor sleep, a daily 600 mg dose of KSM-66 ashwagandha improved sleep onset, duration and efficiency compared with a placebo, performing comparably to 3 mg of melatonin. A combination of the two worked best, with only mild side effects reported.

A separate 12-week trial in 66 post-menopausal women found that 600 mg of ashwagandha daily improved sleep quality, menopause symptoms and quality of life versus placebo, with no serious side effects.

A third trial in 85 children aged 6 to 12 found that ashwagandha gummies improved processing speed and parent-reported sleep quality over eight weeks, and were well tolerated.

Experts caution that ashwagandha has been linked in rare cases to liver injury and thyroid changes, and is generally advised against in pregnancy. Anyone considering it should consult a doctor first, particularly if they take other medication.