Taking selenium supplements for three months lowers one type of thyroid antibody (TPOAb) but does not significantly lower another (TgAb) in people with autoimmune thyroiditis who have normal thyroid function.
Evidence from Studies
No evidence studies found yet.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
Whether selenium supplementation consistently reduces TPOAb but not TgAb across multiple RCTs, and whether this pattern holds across different selenium formulations and baseline antibody levels.
A systematic review and meta-analysis of all RCTs comparing selenium (≥100 μg/day) to placebo in euthyroid autoimmune thyroiditis, reporting changes in both TPOAb and TgAb as primary outcomes, with subgroup analysis by baseline TPOAb/TgAb ratio and selenium form.
Whether selenium selectively targets TPOAb over TgAb in a controlled setting, independent of other variables.
A double-blind RCT with 200 euthyroid autoimmune thyroiditis patients (TPOAb > 100 IU/mL, TgAb > 100 IU/mL) randomized to 200 μg/day selenium or placebo for 6 months, with primary endpoints being relative changes in TPOAb and TgAb, measured by identical assays and blinded lab analysis.
Whether patients with higher baseline TgAb relative to TPOAb are less likely to respond to selenium supplementation.
A prospective cohort study following 300 euthyroid autoimmune thyroiditis patients for 2 years, stratifying by baseline TPOAb/TgAb ratio, and tracking antibody changes after selenium supplementation.
Whether responders to selenium (TPOAb reduction ≥30%) have different immune profiles (e.g., T-cell subsets, cytokine levels) than non-responders.
A case-control study comparing 50 responders (TPOAb reduction ≥30%) to 50 non-responders (TPOAb change <10%) after selenium supplementation, measuring serum cytokines, T-cell phenotypes, and selenium-dependent enzyme activity.
Whether TPOAb and TgAb titers correlate differently with oxidative stress markers in the same individuals.
A cross-sectional analysis of 400 euthyroid autoimmune thyroiditis patients measuring TPOAb, TgAb, MDA, and TAC simultaneously to compare correlation strengths between each antibody and oxidative markers.