Environmental and societal influences acting on cardiovascular risk factors and disease at a population level: a review

Clara Kayei Chow, Karen Lock, Koon Teo, S V Subramanian, Martin McKee, Salim Yusuf, Clara Kayei Chow, Karen Lock, Koon Teo, S V Subramanian, Martin McKee, Salim Yusuf

Abstract

It has long been known that cardiovascular disease (CVD) rates vary considerably among populations, across space and through time. It is now apparent that most of the attributable risk for myocardial infarction 'within' populations from across the world can be ascribed to the varying levels of a limited number of risk factors among individuals in a population. Individual risk factors (e.g. blood pressure) can be modified with resulting health gains. Yet, the persistence of large international variations in cardiovascular risk factors and resulting CVD incidence and mortality indicates that there are additional factors that apply to 'populations' that are important to understand as part of a comprehensive approach to CVD control. This article reviews the evidence on why certain populations are more at risk than others.

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Figure 1
Environmental factors that have been linked to human behaviours and established risk factors that cause cardiovascular diseases

References

    1. Lopez AD, Mathers CD, Ezzati M, Jamison DT, Murray CJL. Global Burden of Disease and Risk Factors. Washington DC: World Bank and Oxford University Press; 2006.
    1. Keys A, Menotti A, Aravanis C, et al. The seven countries study: 2,289 deaths in 15 years. Prev Med. 1984;13:141–54.
    1. Menotti A, Puddu PE, Lanti M, Kromhout D, Blackburn H, Nissinen A. Twenty-five-year coronary mortality trends in the seven countries study using the accelerated failure time model. Eur J Epidemiol. 2003;18:113–22.
    1. WHO Europe: Health for All database. Copenhargen: WHO; 2007.
    1. Yusuf S, Hawken S, Ounpuu S, et al. Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): case-control study. Lancet. 2004;364:937–52.
    1. Rose G. The Strategy of Preventive Medicine. New York: Oxford University Press; 1992.
    1. Szreter S. Industrialization and health. Br Med Bull. 2004;69:75–86.
    1. Zatonski WA, McMichael AJ, Powles JW. Ecological study of reasons for sharp decline in mortality from ischaemic heart disease in Poland since 1991. BMJ. 1998;316:1047–51.
    1. Marmot MG, Syme SL. Acculturation and coronary heart disease in Japanese-Americans. Am J Epidemiol. 1976;104:225–47.
    1. Kindig DA. Understanding population health terminology. Milbank Q. 2007;85:139–61.
    1. Chaloupka FJ. Macro-social influences: the effects of prices and tobacco-control policies on the demand for tobacco products. Nicotine Tob Res. 1999;1(Suppl 1):S105–9.
    1. Ross H, Chaloupka FJ. The effect of cigarette prices on youth smoking. Health Econ. 2003;12:217–30.
    1. Hu TW, Mao Z. Effects of cigarette tax on cigarette consumption and the Chinese economy. Tob Control. 2002;11:105–8.
    1. Wilson N, Thomson G. Tobacco tax as a health protecting policy: a brief review of the New Zealand evidence. NZ Med J. 2005;118:U1403.
    1. Lee JM, Hwang TC, Ye CY, Chen SH. The effect of cigarette price increase on the cigarette consumption in Taiwan: evidence from the National Health Interview Surveys on cigarette consumption. BMC Public Health. 2004;4:61.
    1. Blecher EH, van Walbeek CP. An international analysis of cigarette affordability. Tob Control. 2004;13:339–46.
    1. Guindon GE, Tobin S, Yach D. Trends and affordability of cigarette prices: ample room for tax increases and related health gains. Tob Control. 2002;11:35–43.
    1. Hyland A, Laux FL, Higbee C, et al. Cigarette purchase patterns in four countries and the relationship with cessation: findings from the International Tobacco Control (ITC) Four Country Survey. Tob Control. 2006;15(Suppl 3):iii59–64.
    1. Delnevo CD, Hrywna M, Foulds J, Steinberg MB. Cigar use before and after a cigarette excise tax increase in New Jersey. Addict Behav. 2004;29:1799–807.
    1. Nyman AL, Taylor TM, Biener L. Trends in cigar smoking and perceptions of health risks among Massachusetts adults. Tob Control. 2002;11(Suppl 2):ii25–28.
    1. Smedslund G, Fisher KJ, Boles SM, Lichtenstein E. The effectiveness of workplace smoking cessation programmes: a meta-analysis of recent studies. Tob Control. 2004;13:197–204.
    1. Thomson G, Wilson N. One year of smokefree bars and restaurants in New Zealand: impacts and responses. BMC Public Health. 2006;6:64.
    1. Saffer H, Chaloupka F. The effect of tobacco advertising bans on tobacco consumption. J Health Econ. 2000;19:1117–37.
    1. Hammond D, Fong GT, Borland R, Cummings KM, McNeill A, Driezen P. Text and graphic warnings on cigarette packages: findings from the international tobacco control four country study. Am J Prev Med. 2007;32:202–9.
    1. Hammond D, McDonald PW, Fong GT, Brown KS, Cameron R. The impact of cigarette warning labels and smoke-free bylaws on smoking cessation: evidence from former smokers. Can J Public Health. 2004;95:201–4.
    1. Chen V, Forster JL. The long-term effect of local policies to restrict retail sale of tobacco to youth. Nicotine Tob Res. 2006;8:371–77.
    1. Stead LF, Lancaster T. Interventions for preventing tobacco sales to minors. Cochrane Database Syst Rev. 2005;(Issue 1) Art. No. CD001497.
    1. Staff M, Bennett CM, Angel P. Is restricting tobacco sales the answer to adolescent smoking? Prev Med. 2003;37:529–33.
    1. Lazovich D, Forster J, Widome R, VanCoevering P. Tobacco possession, use, and purchase laws and penalties in Minnesota: enforcement, tobacco diversion programs, and youth awareness. Nicotine Tob Res. 2007;9(Suppl 1):S57–64.
    1. Levy DT, Friend K, Holder H, Carmona M. Effect of policies directed at youth access to smoking: results from the SimSmoke computer simulation model. Tob Control. 2001;10:108–16.
    1. Farrelly MC, Pechacek TF, Chaloupka FJ. The impact of tobacco control program expenditures on aggregate cigarette sales: 1981–2000. J Health Econ. 2003;22:843–59.
    1. Gross CP, Soffer B, Bach PB, Rajkumar R, Forman HP. State expenditures for tobacco-control programs and the tobacco settlement. N Engl J Med. 2002;347:1080–86.
    1. Joossens L, Raw M. The Tobacco Control Scale: a new scale to measure country activity. Tob Control. 2006;15:247–53.
    1. Eriksen MP. Social forces and tobacco in society. Nicotine Tob Res. 1999;1(Suppl 1):S79–80.
    1. Friend K, Levy DT. Reductions in smoking prevalence and cigarette consumption associated with mass-media campaigns. Health Educ Res. 2002;17:85–98.
    1. Rani M, Bonu S, Jha P, Nguyen SN, Jamjoum L. Tobacco use in India: prevalence and predictors of smoking and chewing in a national cross sectional household survey. Tob Control. 2003;12:e4.
    1. Global Tobacco Surveillance System (GTSS): purpose, production, and potential. J Sch Health. 2005;75:15–24.
    1. Yuksel H, Corbett KK. Mixed messages: a qualitative study of the meanings and context of high school students’ tobacco use in Turkey. Health Promot Int. 2005;20:360–66.
    1. Pokorny SB, Jason LA, Schoeny ME. Current smoking among young adolescents: assessing school based contextual norms. Tob Control. 2004;13:301–7.
    1. Poulsen LH, Osler M, Roberts C, Due P, Damsgaard MT, Holstein BE. Exposure to teachers smoking and adolescent smoking behaviour: analysis of cross sectional data from Denmark. Tob Control. 2002;11:246–51.
    1. Borland R, Yong HH, Cummings KM, Hyland A, Anderson S, Fong GT. Determinants and consequences of smoke-free homes: findings from the International Tobacco Control (ITC) Four Country Survey. Tob Control. 2006;15(Suppl 3):iii42–50.
    1. Alamar B, Glantz SA. Effect of increased social unacceptability of cigarette smoking on reduction in cigarette consumption. Am J Public Health. 2006;96:1359–63.
    1. Swinburn B, Egger G, Raza F. Dissecting obesogenic environments: the development and application of a framework for identifying and prioritizing environmental interventions for obesity. Prev Med. 1999;29:563–70.
    1. Popkin BM, Horton SH, Kim S. The Nutrition Transition and Prevention of Diet-related Disease in Asia and the Pacific. Tokyo: The United Nations University, United Nations University Press; 2001.
    1. Saelens BE, Sallis JF, Frank LD. Environmental correlates of walking and cycling: findings from the transportation, urban design, and planning literatures. Ann Behav Med. 2003;25:80–91.
    1. Swinburn B, Egger G. Preventive strategies against weight gain and obesity. Obes Rev. 2002;3:289–301.
    1. Owen N, Humpel N, Leslie E, Bauman A, Sallis JF. Understanding environmental influences on walking; Review and research agenda. Am J Prev Med. 2004;27:67–76.
    1. Humpel N, Owen N, Leslie E. Environmental factors associated with adults’ participation in physical activity: a review. Am J Prev Med. 2002;22:188–99.
    1. Ferreira I, van der Horst K, Wendel-Vos W, Kremers S, van Lenthe FJ, Brug J. Environmental correlates of physical activity in youth - a review and update. Obes Rev. 2007;8:129–54.
    1. Cunningham GO, Michael YL. Concepts guiding the study of the impact of the built environment on physical activity for older adults: a review of the literature. Am J Health Promot. 2004;18:435–43.
    1. van der Horst K, Oenema A, Ferreira I, et al. A systematic review of environmental correlates of obesity-related dietary behaviors in youth. Health Educ Res. 2007;22:203–26.
    1. Cummins S, Macintyre S. Food environments and obesity–neighbourhood or nation? Int J Epidemiol. 2006;35:100–4.
    1. Caraher M, Coveney J. Public health nutrition and food policy. Public Health Nutr. 2004;7:591–98.
    1. De Bourdeaudhuij I, Sallis JF, Saelens BE. Environmental correlates of physical activity in a sample of Belgian adults. Am J Health Promot. 2003;18:83–92.
    1. Humpel N, Owen N, Iverson D, Leslie E, Bauman A. Perceived environment attributes, residential location, and walking for particular purposes. Am J Prev Med. 2004;26:119–25.
    1. Sallis JF, Hovell MF, Hofstetter CR, et al. Distance between homes and exercise facilities related to frequency of exercise among San Diego residents. Public Health Rep. 1990;105:179–85.
    1. Diez Roux AV, Evenson KR, McGinn AP, et al. Availability of recreational resources and physical activity in adults. Am J Public Health. 2007;97:493–99.
    1. Saelens BE, Sallis JF, Black JB, Chen D. Neighborhood-based differences in physical activity: an environment scale evaluation. Am J Public Health. 2003;93:1552–28.
    1. Hoehner CM, Brennan Ramirez LK, Elliott MB, Handy SL, Brownson RC. Perceived and objective environmental measures and physical activity among urban adults. Am J Prev Med. 2005;28(2 Suppl 2):105–16.
    1. Boehmer TK, Hoehner CM, Deshpande AD, Brennan Ramirez LK, Brownson RC. Perceived and observed neighborhood indicators of obesity among urban adults. Int J Obes (Lond) 2007;31:968–77.
    1. Huston SL, Evenson KR, Bors P, Gizlice Z. Neighborhood environment, access to places for activity, and leisure-time physical activity in a diverse North Carolina population. Am J Health Promot. 2003;18:58–69.
    1. From the Centers for Disease Control and Prevention. Neighborhood safety and the prevalence of physical inactivity–selected states, 1996. JAMA. 1999;281:1373.
    1. Raudenbush S, Sampson RJ. ‘Ecometrics’: toward a Science of assessing ecological settings, with application to the systematic social observation of neighborhoods. Sociol Methodology. 1999;29:1–41.
    1. King WC, Brach JS, Belle S, Killingsworth R, Fenton M, Kriska AM. The relationship between convenience of destinations and walking levels in older women. Am J Health Promot. 2003;18:74–82.
    1. King AC, Toobert D, Ahn D, et al. Perceived environments as physical activity correlates and moderators of intervention in five studies. Am J Health Promot. 2006;21:24–35.
    1. Boehmer TK, Lovegreen SL, Haire-Joshu D, Brownson RC. What constitutes an obesogenic environment in rural communities? Am J Health Promot. 2006;20:411–21.
    1. Frank LD, Andresen MA, Schmid TL. Obesity relationships with community design, physical activity, and time spent in cars. Am J Prev Med. 2004;27:87–96.
    1. Araya R, Montgomery A, Rojas G, et al. Common mental disorders and the built environment in Santiago, Chile. Br J Psychiatry. 2007;190:394–401.
    1. Brownson RC, Chang JJ, Eyler AA, et al. Measuring the environment for friendliness toward physical activity: a comparison of the reliability of 3 questionnaires. Am J Public Health. 2004;94:473–83.
    1. Ewing R, Schmid T, Killingsworth R, Zlot A, Raudenbush S. Relationship between urban sprawl and physical activity, obesity, and morbidity. Am J Health Promot. 2003;18:47–57.
    1. Ewing R, Brownson RC, Berrigan D. Relationship between urban sprawl and weight of United States youth. Am J Prev Med. 2006;31:464–74.
    1. Frank LD, Schmid TL, Sallis JF, Chapman J, Saelens BE. Linking objectively measured physical activity with objectively measured urban form: findings from SMARTRAQ. Am J Prev Med. 2005;28(2 Suppl 2):117–25.
    1. Pikora TJ, Bull FC, Jamrozik K, Knuiman M, Giles-Corti B, Donovan RJ. Developing a reliable audit instrument to measure the physical environment for physical activity. Am J Prev Med. 2002;23:187–94.
    1. Cunningham GO, Michael YL, Farquhar SA, Lapidus J. Developing a reliable senior walking environmental assessment tool. Am J Prev Med. 2005;29:215–17.
    1. Day K, Boarnet M, Alfonzo M, Forsyth A. The Irvine-Minnesota inventory to measure built environments: development. Am J Prev Med. 2006;30:144–52.
    1. Weich S, Burton E, Blanchard M, Prince M, Sproston K, Erens B. Measuring the built environment: validity of a site survey instrument for use in urban settings. Health Place. 2001;7:283–92.
    1. Pikora TJ, Giles-Corti B, Knuiman MW, Bull FC, Jamrozik K, Donovan RJ. Neighborhood environmental factors correlated with walking near home: Using SPACES. Med Sci Sports Exerc. 2006;38:708–14.
    1. Brennan Ramirez LK, Hoehner CM, Brownson RC, et al. Indicators of activity-friendly communities: an evidence-based consensus process. Am J Prev Med. 2006;31:515–24.
    1. Foster C, Hillsdon M, Thorogood M. Environmental perceptions and walking in English adults. J Epidemiol Community Health. 2004;58:924–28.
    1. Glanz K, Sallis JF, Saelens BE, Frank LD. Healthy nutrition environments: concepts and measures. Am J Health Promot. 2005;19:330–33, ii.
    1. Story M, Kaphingst KM, Robinson-O’Brien R, Glanz K. Creating healthy food and eating environments: policy and environmental approaches. Annu Rev Public Health. 2008;29:253–72.
    1. White M. Food access and obesity. Obes Rev. 2007;8(Suppl 1):99–107.
    1. Morland K, Diez Roux AV, Wing S. Supermarkets, other food stores, and obesity: the atherosclerosis risk in communities study. Am J Prev Med. 2006;30:333–39.
    1. Morland K, Wing S, Diez Roux A, Poole C. Neighborhood characteristics associated with the location of food stores and food service places. Am J Prev Med. 2002;22:23–29.
    1. Powell LM, Slater S, Mirtcheva D, Bao Y, Chaloupka FJ. Food store availability and neighborhood characteristics in the United States. Prev Med. 2007;44:189–95.
    1. Pearson T, Russell J, Campbell MJ, Barker ME. Do ‘food deserts’ influence fruit and vegetable consumption?–A cross-sectional study. Appetite. 2005;45:195–97.
    1. Macintyre S. Deprivation amplification revisited; or, is it always true that poorer places have poorer access to resources for healthy diets and physical activity? Int J Behav Nutr Phys Act. 2007;4:32.
    1. Dibsdall LA, Lambert N, Bobbin RF, Frewer LJ. Low-income consumers’ attitudes and behaviour towards access, availability and motivation to eat fruit and vegetables. Public Health Nutr. 2003;6:159–68.
    1. Turrell G, Blakely T, Patterson C, Oldenburg B. A multilevel analysis of socioeconomic (small area) differences in household food purchasing behaviour. J Epidemiol Community Health. 2004;58:208–15.
    1. Giskes K, Van Lenthe FJ, Brug J, Mackenbach JP, Turrell G. Socioeconomic inequalities in food purchasing: the contribution of respondent-perceived and actual (objectively measured) price and availability of foods. Prev Med. 2007;45:41–48.
    1. Burns CM, Gibbon P, Boak R, Baudinette S, Dunbar JA. Food cost and availability in a rural setting in Australia. Rural Remote Health. 2004;4:311.
    1. Lee AJ, Darcy AM, Leonard D, et al. Food availability, cost disparity and improvement in relation to accessibility and remoteness in Queensland. Aust NZ J Public Health. 2002;26:266–72.
    1. Reidpath DD, Burns C, Garrard J, Mahoney M, Townsend M. An ecological study of the relationship between social and environmental determinants of obesity. Health Place. 2002;8:141–15.
    1. Maddock J. The relationship between obesity and the prevalence of fast food restaurants: state-level analysis. Am J Health Promot. 2004;19:137–43.
    1. Cummins SC, McKay L, MacIntyre S. McDonald's restaurants and neighborhood deprivation in Scotland and England. Am J Prev Med. 2005;29:308–10.
    1. Macintyre S, McKay L, Cummins S, Burns C. Out-of-home food outlets and area deprivation: case study in Glasgow, UK. Int J Behav Nutr Phys Act. 2005;2:16.
    1. Saelens BE, Glanz K, Sallis JF, Frank LD. Nutrition Environment Measures Study in restaurants (NEMS-R): development and evaluation. Am J Prev Med. 2007;32:273–81.
    1. Glanz K, Sallis JF, Saelens BE, Frank LD. Nutrition Environment Measures Survey in stores (NEMS-S): development and evaluation. Am J Prev Med. 2007;32:282–89.
    1. Wang MC, Gonzalez AA, Ritchie LD, Winkleby MA. The neighborhood food environment: sources of historical data on retail food stores. Int J Behav Nutr Phys Act. 2006;3:15.
    1. Lewis LB, Sloane DC, Nascimento LM, et al. African Americans’ access to healthy food options in South Los Angeles restaurants. Am J Public Health. 2005;95:668–73.
    1. Hawkes C. The role of foreign direct investment in the nutrition transition. Public Health Nutr. 2005;8:357–65.
    1. Yach D, McKee M, Lopez AD, Novotny T, for Oxford V. Improving diet and physical activity: 12 lessons from controlling tobacco smoking. BMJ. 2005;330:898–900.
    1. Mytton O, Gray A, Rayner M, Rutter H. Could targeted food taxes improve health? J Epidemiol Community Health. 2007;61:689–94.
    1. China Salt Substitute Collaborative Group. Salt substitution: a low-cost strategy for blood pressure control among rural Chinese. A randomized, controlled trial. J Hypertens. 2007;25:2011–18.
    1. Food CPI. prices and expenditures: food expenditures by families and individuals as a share of disposable personal income: United States Department of Agriculture: Economic Research Service. 2006.
    1. Vinck P. Strengthening Emergency Needs Assessment Capacity (SENAC) Rome: United Nations World Food Program; 2006. Comprehensive Food Security and Vulnerability Analysis, Rural Uganda – 2005.
    1. Miller KA, Siscovick DS, Sheppard L, et al. Long-term exposure to air pollution and incidence of cardiovascular events in women. N Engl J Med. 2007;356:447–58.
    1. Lanki T, Pekkanen J, Aalto P, et al. Associations of traffic related air pollutants with hospitalisation for first acute myocardial infarction: the HEAPSS study. Occup Environ Med. 2006;63:844–51.
    1. Barnett AG, Williams GM, Schwartz J, et al. The effects of air pollution on hospitalizations for cardiovascular disease in elderly people in Australian and New Zealand cities. Environ Health Perspect. 2006;114:1018–23.
    1. Ballester F, Rodriguez P, Iniguez C, et al. Air pollution and cardiovascular admissions association in Spain: results within the EMECAS project. J Epidemiol Community Health. 2006;60:328–36.
    1. Bhatnagar A. Environmental cardiology: studying mechanistic links between pollution and heart disease. Circ Res. 2006;99:692–705.
    1. Routledge HC, Ayres JG. Air pollution and the heart. Occup Med (Lond) 2005;55:439–47.
    1. Maitre A, Bonneterre V, Huillard L, Sabatier P, de Gaudemaris R. Impact of urban atmospheric pollution on coronary disease. Eur Heart J. 2006;27:2275–84.
    1. Brook RD, Franklin B, Cascio W, et al. Air pollution and cardiovascular disease: a statement for healthcare professionals from the Expert Panel on Population and Prevention Science of the American Heart Association. Circulation. 2004;109:2655–71.
    1. Forastiere F, Stafoggia M, Tasco C, et al. Socioeconomic status, particulate air pollution, and daily mortality: differential exposure or differential susceptibility. Am J Ind Med. 2007;50:208–16.
    1. Baccini M, Biggeri A, Accetta G, Lagazio C, Lerxtundi A, Schwartz J. Comparison of alternative modelling techniques in estimating short-term effect of air pollution with application to the Italian meta-analysis data (MISA Study) Epidemiol Prev. 2006;30:279–88.
    1. Edwards DP. Air Quality Remote Sensing From Space, Eos Trans. Americal Geophysical Union. 2006;87:327.
    1. Watkins T, Dimmick F, Holland D, et al. Air quality characterization for environmental public health tracking. In: Borrego C, Renner E, editors. Developments in Environmental Sciences: Air Pollution Modeling and Its Application XVIII. St. Louis, MO: Elsevier; 2007. pp. 717–27.
    1. Engel-Cox JA, Hoff RM, Rogers R, et al. Integrating lidar and satellite optical depth with ambient monitoring for 3-dimensional particulate characterization. Atmospheric Environment. 2006;40:8056–67.
    1. Gupta P, Christopher SA, Wang J, Gehrig R, Lee Y, Kumar N. Satellite remote sensing of particulate matter and air quality assessment over global cities. Atmospheric Environment. 2006;40:5880–92.
    1. Sahsuvaroglu T, Arain A, Kanaroglou P, et al. A land use regression model for predicting ambient concentrations of nitrogen dioxide in Hamilton, Ontario, Canada. J Air Waste Manag Assoc. 2006;56:1059–69.
    1. Engels F. The Condition of the Working Class in England. London: Penguin; 1987.
    1. Virchow R. Die Epidemie von 1848. Virch Arch. 1851;3:3–13.
    1. Turnock BJ. Public Health: What It Is and How It Works. Boston. Boston: Jones and Bartlett; 2004.
    1. World Health Organisation Health systems: improving performance. Geneva: WHO; 2000.
    1. Oakes JM. Commentary: advancing neighbourhood-effects research–selection, inferential support, and structural confounding. Int J Epidemiol. 2006;35:643–47.
    1. Messer LC. Invited commentary: Beyond the metrics for measuring neighborhood effects. Am J Epidemiol. 2007;165:868–71. discussion 872–73.
    1. Subramanian SV. The relevance of multilevel statistical methods for identifying causal neighborhood effects. Soc Sci Med. 2004;58:1961–67.
    1. Subramanian SV, Glimour MM, Kawachi I. Identifying causal effects on health: a methodological assessment. In: Galea S, editor. Macroscocial Determinants of Population Health. New York: Springer; 2007. pp. 301–31.
    1. Booth KM, Pinkston MM, Poston WS. Obesity and the built environment. J Am Diet Assoc. 2005;105(5 Suppl 1):S110–17.
    1. Golstein H. Multilevel statistical models. London: Institute of Education; 1999.
    1. Langford IH, Leyland AH, Rasbash J, Goldstein H. Multilevel modelling of the geographical distributions of diseases. J R Stat Soc Ser C Appl Stat. 1999;48:253–68.
    1. Subramanian SV, Jones K, Duncan C. Multilevel methods for public health research. In: Kawachi I, Berkman LF, editors. Neighbourhoods and Health. New York: Oxford University Press; 2003. pp. 65–111.
    1. Butland B, Jebb S, Kopleman P, et al. Foresight. Tackling obesities: future choices- project report. London: Government Office for Science; 2007.

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