Research summary
Ashwagandha and Thyroid Function
A small pilot trial examined thyroid laboratory indices in adults with subclinical hypothyroidism. It does not establish symptom improvement, long-term benefit, or benefit in overt hypothyroidism.[1]
What these findings do not establish
Based on a single small pilot trial of 50 adults with subclinical hypothyroidism using 600 mg per day for 8 weeks; it does not establish symptom improvement, long-term benefit, or benefit in overt hypothyroidism and should not replace prescribed thyroid management.[1]
What the pilot trial can establish
In a small randomized, double-blind, placebo-controlled trial of adults with subclinical hypothyroidism, ashwagandha root extract significantly improved serum TSH, T3, and T4 levels compared with placebo. Based on a single small pilot trial of 50 adults with subclinical hypothyroidism using 600 mg per day for 8 weeks; it does not establish symptom improvement, long-term benefit, or benefit in overt hypothyroidism and should not replace prescribed thyroid management.[1]
Relevant safety guidance
NCCIH does not recommend ashwagandha for people with thyroid or autoimmune disorders or those who are about to have surgery. Discuss these conditions and any planned surgery with your healthcare professional before considering ashwagandha; supplement research does not justify changing prescribed care.[2]
References
- Efficacy and Safety of Ashwagandha Root Extract in Subclinical Hypothyroid Patients: A Double-Blind, Randomized Placebo-Controlled Trial.. Journal of alternative and complementary medicine (New York, N.Y.). 2018. Randomized controlled trial View source →
- Ashwagandha: Usefulness and Safety. NIH National Center for Complementary and Integrative Health. Retrieved 2026-09-30. Government health fact sheet View source →
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