1. Department of Internal Medicine of Laiwu People's Hospital Branch of Shandong Province; Shandong China
2. Department of Endocrinology of Laiwu People's Hospital of Shandong Province; Shandong China
3. Department of Nutrition and Carolina Population Center; University of North Carolina at Chapel Hill; Chapel Hill NC USA
4. Laiwu Maternal and Child Health Hospital of Shandong Province; Shandong China