Abstract              Background: Vitamin D deficiency and hypothyroidism are common problems in India. Vitamin D not only has action on calcium metabolism, but its deficiency is considered as cause for autoimmune diseases. Currently, only animal trials are available, cause and effect relationship between vitamin D deficiency and autoimmune diseases is yet to be proved in human beings. Hypothyroidism is also known to have effects on calcium homeostasis. Our aim was to study vitamin D status in hypothyroid patients and compare it with normal controls. Subjects and Methods: We studied 50 patients with hypothyroidism and 50 normal controls who visited our outpatient department. Vitamin D levels and thyroid profile were sent in all 100 patients. Vitamin D deficiency was designated at <20ng/ml. Results: Vitamin D deficiency was found in 73% of patients with hypothyroidism. Even among hypothyroid patients, people with TSH under normal limits vitamin D deficiency prevalence (45% in hypothyroid patients) were comparable to that of normal controls (44% in controls). T test was applied between uncontrolled hypothyroid group and normal control group and p value was 0.0023, t= 2.9. There was no statistical significance difference between males and females t=1.3, p=0.08. There was negative correlation between TSH levels and vitamin D levels in patients with hypothyroidism suggesting the uncontrolled the hypothyroidism the lower would be the vitamin D levels. Conclusion: Vitamin D levels must be checked in all hypothyroid patients, specifically in people with age 50-59 years, uncontrolled hypothyroidism as both uncontrolled hypothyroidism and vitamin D deficiency may present with similar nonspecific complaints.

Key Words: Vitamin D deficiency, Hypothyroidism, normal controls.