BMC Public Health 2009, 9:130 http://www.biomedcentral.com/1471-2458/9/130 protein; CVD: cardiovascular disease; DBP: diastolic blood pressure; HDL: high-density lipoprotein; IL-6: interleukin-6; LDL: low-density lipoprotein; MetS: meta- bolic syndrome; OR: odds ratio; PAI-1: plasminogen acti- vator inhibitor-1; RBP4: retinol-binding protein 4; SBP: systolic blood pressure; SD: standard deviation; SRH: self rated health; TG: triglycerides; TCH: total cholesterol. Competing interests The authors declare that they have no competing interests. Authors' contributions All authors mentioned participated actively in all and each of the following aspects for this article: Conception and design, or analysis and interpretation of data, drafting the article or revising it critically for important intellectual content and final approval of the version to be published. Acknowledgements The authors want to express their sincere appreciation to the study partic- ipants and to the researchers and the healthcare professionals from the Centers for Disease Control and Prevention in Beijing and in Shanghai. The authors also want to thank Dr. Yong Liu, Dr. Huaixing Li, Wang Jing, Xing- wang Ye and Qibin Qi for their help in conducting laboratory assayes for biomakers and Dr Hilde Hendrickxs and Dr. Gabrielle Osborne for their valuable comments. This study was funded by grants SIBS2008006 from the Chief Scientist Pro- gram of Shanghai Institutes for Biological Sciences, Chinese Academy of Sci- ences to Dr. Xu Lin, KSCX1-YW-02 and KSCX1-YW-R-116 from the Knowledge Innovation Program of the Chinese Academy of Sciences, CH- 2006-0941 from the Shanghai-Unilever Research Development Fund. 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