TPO and autoimmune thyroid disease: The immunomodulatory role of vitamin D in preventing autoimmune diseases by telorogenic dendritic cells induction has been widely explored.5-9 Studies shows lower levels of vitamin D can lead to autoimmune diseases as autoimmune thyroid.10-12 In contrast, a study assessing antithyroid peroxidase antibody (TPO-Ab) level in two categories of vitamin D; above and below 25 nmol/l of serum 25-hydroxy vitamin D [25(OH) D] found the prevalence of TPO-Ab was comparable between the groups.13