A double-blind, placebo-controlled clinical trial from 2019, recruited 71 children and adolescents with autoimmune thyroiditis and thyroid antibodies (anti-TPO and anti-TG) >60IU/mL. Subjects were randomized to 200 mcg l-selenomethionine (SeMet) or placebo daily for six months. The SeMet group had a significantly greater reduction in anti-TG levels compared to the placebo group.
Kyrgios, I., Giza, S., Kotanidou, E. P., Kleisarchaki, A., Tsinopoulou, V. R., Papadopoulou, A., Markantonatou, A. M., Kanellidou, E., Giannakou, A., & Galli-Tsinopoulou, A. (2019). l-selenomethionine supplementation in children and adolescents with autoimmune thyroiditis: A randomized double-blind placebo-controlled clinical trial. Journal of clinical pharmacy and therapeutics, 44(1), 102–108. https://doi.org/10.1111/jcpt.12765