Association of Serum Vitamin D Status and Waist Circumference on Obesity with Type 2 Diabetes: A Cross-sectional Study in Rural Adults of Henan

Obesity and T2DM have now become serious epidemics in public health issues worldwide. T2DM is considered a multifactorial disease, which is promoted by genetic and environmental factors and characterized by chronic hyperglycemia and insulin resistance (IR)[1]. According to the report of the World Health Organization, overweight and obesity account for 44％ of diabetes cases in most European countries; overweight and obesity are also responsible for about 80％ of T2DM cases[2], suggesting that obesity is deeply involved in T2DM development. Being overweight itself increases the risk of the same complications as obesity. The risk is particularly high when excess adipose tissue is distributed intra-abdominally [as characterized by a high waist circumference (WC)][1]. Obese T2DM patients not only have worse metabolic control than normal-weight T2DM patients but also are at an extremely high risk of future diabetes-related cardiovascular–renal complications, which may, in turn, increase the mortality risk of individuals seven-fold.