Tehran University of Medical Sciences Journal of Nutritional Sciences and Dietetics 4 4 2018 12 01 147 157 Ahmad Jayedi Food (Salt) Safety Research Center, Semnan University of Medical Sciences, Semnan, Iran. Mahdieh Sadat Zargar Nursing Care Research Center, Semnan University of Medical Sciences, Semnan, Iran AND Department of Community, Nutrition, School of Nutritional Science and Dietetics, Tehran University of Medical Sciences, Tehran, Iran. 2019 04 11 Background: The association of obesity with risk of chronic kidney disease has been accepted, but considering the possible indications of the obesity paradox in patients with early-stage kidney disease, the association between baseline body mass index (BMI) and future risk of end-stage renal disease (ESRD) in the general population has not been established yet. Methods: We performed a systematic search of PubMed and Scopus for relevant studies published from database inception to June 2018. Longitudinal cohort studies reporting risk estimates of ESRD for three or more categories of BMI in the general population were included. Pooled relative risk (RR) was calculated using a random-effects model. Results: The analysis included eight prospective cohort studies, one nested case-control study, one nested case-referent study, and two retrospective cohort studies (2,063,895 individuals and 5874 cases of end-stage renal disease). The pooled RR of ESRD for a 5-unit increment in BMI was 1.19 (95%CI: 1.06, 1.35; I2 = 94.1%). The strength of the association might be age-related; in a way that, a significant positive association was found in those with a mean age <50 years, but not those aged ≥50 years. A nonlinear dose-response meta-analysis indicated that the risk of ESRD was similar within BMI of 15-23 kg/m2, and then increased sharply and linearly at a BMI of approximately 25 kg/m2. Conclusion: Obesity and overweight condition are associated with a higher risk of ESRD. Being as lean as possible within the normal weight range may help to prevent ESRD. https://jnsd.tums.ac.ir/index.php/jnsd/article/view/255