Ochiai H, et al. - Via performing a cross-sectional study involving 94,822 adults aged 40–64 years who had annual health check-ups in Japan from April 2013 to March 2014, researchers assessed the association of the combination of weight gain after 20 years of age and current obesity with chronic kidney disease (CKD) among adults. In comparison to weight gain < 10 kg plus non-obesity in men, both weight gain ≥ 10 kg after 20 years of age plus obesity and weight gain of ≥ 10 kg plus non-obesity markedly progressed the OR for CKD. In women, weight gain ≥ 10 kg plus obesity and weight gain ≥ 10 kg plus non-obesity significantly enhanced the OR for CKD as that of weight gain < 10 kg plus non-obesity. Thus, in both obese and non-obese subjects, a significant association among weight gain ≥ 10 kg after 20 years of age with CKD was observed. Furthermore, the impact of weight gain ≥ 10 kg plus obesity was higher than that of weight gain ≥ 10 kg plus non-obesity on CKD. Therefore, in an effort to control CKD among Japanese middle-aged adults, the investigators suggested that it is important to acknowledge weight gain after maturity in both obese and non-obese subjects.