Home / Ingredients / Ashwagandha (Withania somnifera)
Some evidence for stress and sleep, but preparation heterogeneity and study quality limit broad conclusions.
NCCIH states that some ashwagandha preparations may help stress and insomnia, while evidence for many other promoted uses remains insufficient. Meta-analyses report benefit for stress/anxiety and sleep but also substantial heterogeneity and limitations.
Trials use different root, leaf, and root/leaf extracts with different standardization and doses, so evidence is not interchangeable across preparations.
Short-term use may be tolerated, but long-term safety is unclear. Rare liver injury has been reported. NCCIH advises avoiding use in pregnancy and breastfeeding and notes several potential medication and thyroid/autoimmune concerns.
NOURISH+ lists ashwagandha but does not publish the extract type, standardization, or dose on the manufacturer page. Trial results cannot be directly assigned to the finished product.
Effects of Ashwagandha (Withania Somnifera) on stress and anxiety: A systematic review and meta-analysis (Systematic review and meta-analysis of randomized controlled trials; PMID 39348746)
Population/scope: 9 randomized trials; 558 participants
Evidence scope: Perceived stress, anxiety, cortisol, and safety
Finding: Pooled results favored ashwagandha for perceived stress, anxiety scores, and cortisol compared with placebo.
Limitations: Formulations and doses varied, the evidence base was relatively small, and long-term safety remains insufficiently characterized.
Directness: Relevant human evidence · verified 2026-10-02
Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysis (Systematic review and meta-analysis of randomized controlled trials; PMID 34559859)
Population/scope: 5 randomized trials; 400 adults
Evidence scope: Sleep quantity, sleep quality, alertness, anxiety, and quality of life
Finding: Ashwagandha produced a small overall improvement in sleep, with larger effects in insomnia, at doses of at least 600 mg/day, and with at least 8 weeks of treatment.
Limitations: The trial base was small and heterogeneous (I² 62% for overall sleep), and long-term safety data were limited.
Directness: Relevant human evidence · verified 2026-10-02
Important: Ingredient-level evidence is not proof that a finished product has the same effect. Dose, form, population, duration, and formulation must match.
For informational purposes only; not individualized medical advice.