Introduction: the sedentary lifestyle is related to the incidence of various diseases and metabolic disorders. The aim of the current study was to understand the link between serum vitamin D levels, thyroid hormones and lipid profiles among Iranian sedentary staff.
Material and methods: in this cross-sectional study, 300 healthy subjects with normal body mass index (BMI) and age between 18 and 65 years, with sedentary lifestyles, were included. Serum levels of 25-hydroxyvitamin D, thyroid stimulating hormone (TSH), fasting blood sugar, plasma total cholesterol, and high-density lipoprotein (HDL) and triglycerides (TG) were measured with qualified laboratory methods. Low-density lipoprotein (LDL) concentration was calculated based on the Friedewald equation. A self-made questionnaire with different questions was used to assess physical activity.
Results: the means of BMI and age were 25.63 ± 10.25 and 36.69 ± 7.14 years, respectively. The prevalence of vitamin D deficiency was 65.7%. Results showed significant differences for TG, HDL, and thyroxine (T4) between subgroup categories. Serum levels of 25-hydroxyvitamin D had a negative significant correlation with triiodothyronine (T3) and T4, and a positive correlation with HDL. Linear regression analysis showed a significant association of 25-hydroxyvitamin D concentrations with HDL and T4 after adjustments based on the sex.
Conclusion: finally, the results of this study show that with the improvement in vitamin D status, the decrease in the levels of TG, T3 and T4, with an increase in HDL can be expected. So, verification and detection of true causality through the interventional studies will be valuable, scientifically.