INS and vitamin D deficiency: Among the 2960 participants, 1982 (67.0%) subjects had vitamin D deficiency, 769 (26.0%) had vitamin D insufficiency, and 209 (7%) had normal vitamin D. Compared with subjects with sufficient vitamin D, subjects with decreased serum 25(OH)D were younger, more obese, and had significantly higher blood glucose, fasting insulin, cholesterol, LDL-c, bone turn-over biomarkers (PTH and ALP), and LFC (All p value <0.05).