Schooling et al. BMC Public Health 2011, 11:345 http://www.biomedcentral.com/1471-2458/11/345 White blood cell count (109/L) Lymphocyte count (109/L) Granulocyte count (109/L) sex men women men women men women 6.8 (1.72) 6.3 (1.52) 2.17 (0.65) 2.18 (0.59) 4.18 (1.38) 3.72 (1.18) 1 2 1 2 1 2 1 2 1 2 1 2 reference reference reference reference reference reference reference reference reference reference reference reference b 0.02 0.02 -0.03 0.01 0.05 0.04 0.003 0.02 -0.01 -0.01 -0.02 0.002 Page 5 of 6 95% CI 0.10 to 0.56 0.04 to 0.49 -0.02 to 0.21 -0.02 to 0.20 0.07 to 0.25 0.06 to 0.23 -0.01 to 0.36 -0.04 to 0.32 -0.04 to 0.15 -0.04 to 0.14 95% CI -0.13 to 0.17 -0.13 to 0.16 -0.11 to 0.05 -0.07 to 0.09 -0.01 to 0.10 -0.01 to 0.10 -0.13 to 0.11 -0.13 to 0.11 -0.09 to 0.04 -0.06 to 0.06 b 0.33 0.27 0.09 0.09 0.16 0.15 0.18 0.14 0.06 0.05 -0.03 to 0.03 -0.01 to 0.05 0.04 -0.004 to 0.09 0.04 -0.004 to 0.08 Table 3 Adjusted Associations of Recalled Childhood Meat Eating with Inflammatory Markers in 9,867 Older Chinese Men (2,498) and Women (7,369) in Phase 3 of the Guangzhou Biobank Cohort Study (2006-8) Mean and (standard deviation) Recalled childhood meat eating Model † <1/week About once a week Almost daily †Model 1 adjusted for age, smoking, parental possessions and education. Model 2 additionally adjusted for body mass index and waist-hip ratio. granulocytes remains to be determined, as do any other possible consequences for immunity or auto-immunity. As such, this hypothesis potentially provides an explana- tion for several previous observations [9,34] as well as ours; nevertheless it remains speculative because puber- tal testosterone is not available in this study. Moreover, our study cannot establish causality; merely provide evi- dence consistent with a hypothesis. Conclusions Protective effects of better childhood conditions may be less evident among men than women at the early stages of economic development, perhaps due to the biological consequences of up-regulation of the gonadotropic axis. Fully delineating the intergenerational and life long bio- logical effects of changes in nutrition with economic development could be key to developing effective inter- ventions and ensuring that men benefit as much as women from economic development. Acknowledgements The Guangzhou Biobank Cohort Study investigators include: Guangzhou No. 12 Hospital: WS Zhang, M Cao, T Zhu, B Liu, CQ Jiang (Co-PI); The University of Hong Kong: CM Schooling, SM McGhee, GM Leung, R Fielding, TH Lam (Co-PI); The University of Birmingham: P Adab, GN Thomas, KK Cheng (Co- PI). This work was supported by the University of Hong Kong Foundation for Development and Research, Hong Kong; The University of Hong Kong University Research Committee Strategic Research Theme Public Health, Hong Kong; Guangzhou Public Health Bureau, and Guangzhou Science and Technology Committee, Guangzhou, China; and The University of Birmingham, Birmingham, UK. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Author details 1School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China. 2Guangzhou Occupational Diseases Prevention and Treatment Centre, Guangzhou Number 12 Hospital, Guangzhou, China. 3Department of Public Health and Epidemiology, University of Birmingham, UK. 4School of Public Health, CUNY, New York, USA. Authors’ contributions THL, CQJ and KKC initiated and oversee the Guangzhou Biobank Cohort Study, WSZ and GML assisted in the planning and co-ordination of the study. CMS designed this analysis. GML contributed to the interpretation of this analysis. CMS drafted the manuscript. All authors critically reviewed the manuscript for intellectual content. All authors read and approved the final manuscript. Competing interests The authors declare that they have no competing interests. Received: 12 October 2010 Accepted: 19 May 2011 Published: 19 May 2011 References 1. Galobardes B, Smith GD, Lynch JW: Systematic review of the influence of childhood socioeconomic circumstances on risk for cardiovascular disease in adulthood. Ann Epidemiol 2006, 16:91-104. 2. Ross R: Atherosclerosis–an inflammatory disease. N Engl J Med 1999, 340:115-126. 3. Jee SH, Park JY, Kim HS, Lee TY, Samet JM: White blood cell count and risk for all-cause, cardiovascular, and cancer mortality in a cohort of Koreans. Am J Epidemiol 2005, 162:1062-1069. 4. Pollitt RA, Kaufman JS, Rose KM, ez-Roux AV, Zeng D, Heiss G: Early-life and adult socioeconomic status and inflammatory risk markers in adulthood. Eur J Epidemiol 2007, 22:55-66.