Serum 25-hydoxyvitamin D concentrations in relation to Hashimoto's thyroiditis: a systematic review, meta-analysis and meta-regression of observational studies.

The present work shows a significant association between circulating 25(OH)D and HT, partly resolves mixed findings by identifying the empirical moderators contributing to overall heterogeneity, and highlights HT patient groups and the conditions under which the association is strongest.