Low Population Selenium Status Is Associated With Increased Prevalence of Thyroid Disease

Context: Epidemiological studies have supported the premise that an adequate selenium intake is essential for thyroid gland function. Objective: The objective was to investigate whether the prevalence of thyroid disease differed in two areas that were similar, except for very different soil/crop selenium concentrations. Design: Cross-sectional observational study. Setting: The setting was two counties of Shaanxi Province, China, here defined as adequate- and low-selenium. Participants: A total of 6152 participants were selected by stratified cluster-sampling. Main Outcome Measures: Participants completed demographic and dietary questionnaires and underwent physical and thyroid ultrasound examinations. Serum samples were analyzed for thyroid function parameters and selenium concentration. Serum selenium was compared between different demographic, dietary, and lifestyle categories in the two counties. The relationship between selenium status, dietary factors, and pathological thyroid conditions was explored...