Background & aims: This study examined the relationship between birthweight and blood pressure in childhood. Methods: Prospective cohort study involving 472 Brazilian children ranging in age from 5 to 8 years. Birthweight, systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), total cholesterol and fractions (LDL-c, HDL-c), and triglycerides were determined. Total cholesterol, LDL-c. HDL-c, and triglycerides were assessed by automated enzymatic methods. Blood pressure was measured with the HDI/Pulse Wave (TM) CR-2000 equipment. Multiple regression models were used to investigate the relationship between birthweight and SBP and DBP, controlling for the following variables: gender, age. BMI, total cholesterol, triglycerides, per capita income, and maternal education. Results: When adjusting for gentler and BMI, we found a systolic blood pressure increase of 2.9 (95% CI = -5.33 to -0.56) mmHg per kilogram birthweight reduction. The unadjusted association was insignificant. Conclusion: Our data suggest that low birthweight is one of the factors contributing to blood pressure elevation at early ages. A way to prevent these diseases is by implementing public policies focused on good nutrition and adequate prenatal care for pregnant women. (c) 2010 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.