The dramatic increase in the prevalence of prediabetes after a 6-y interval may be attributable to the following reasons: (1) at follow-up, most of the subjects were at puberty, a period of increased insulin resistance [14]; (2) twins are more insulin resistant than singletons[15]; (3) rapid economic, nutritional, and lifestyle changes observed in China over the recent decades. Here, INS is linked to prediabetes syndrome.