TPO and vitamin D deficiency: The risk analysis in our study showed that in vitamin D deficiency, the presence of HT increased by 3.107 fold (OR: 3.107, %95 CI: 1.530-6.307, p= 0.001), and anti-TPO positivity increased by 2.604 fold (OR: 2.604, %95 CI: 1.280-5.291, p= 0.004).