Ashwagandha for Thyroid Health

Research suggests that ashwagandha may support thyroid function by modestly influencing thyroid hormone levels, with a 2023 narrative review reporting increases in T3 and T4 alongside reductions in TSH, and a 2026 review on thyroid nodules noting preclinical and limited human evidence of potential benefit — though both conclude that high-quality clinical evidence remains insufficient to draw firm conclusions. Studies indicate the supplement appears generally well-tolerated in healthy adults across multiple short-term safety trials, including randomized controlled trials and observational studies, with thyroid hormone levels remaining within normal ranges in most participants who were not specifically selected for thyroid conditions. The picture becomes more complicated in certain populations: a 2025 safety review raised concerns about ashwagandha use in people with existing thyroid conditions, flagged multiple case reports of liver damage, and recommended stronger regulatory oversight, while a separate 2025 systematic review found that reproductive and developmental safety claims — both for and against — often lack reliable primary source support. Overall, the body of evidence on ashwagandha and thyroid health is composed largely of short-duration studies in healthy populations, making it difficult to draw conclusions about long-term effects or outcomes in people with thyroid disorders, and further rigorous clinical research is needed.