Obesity epidemics: inevitable outcome of globalization or preventable public health challenge?

Abstract

This editorial addresses the public health challenge of theestablished and emerging global obesity epidemics. As thearticle by Moura and Claro in this issue highlights, obesityrates and associated non-communicable diseases, such ascardiovascular disease, diabetes and certain cancers, havebeen escalating worldwide over the past four decades.While obesity has reached established epidemic propor-tions in high income countries such as the USA, Canadaand the UK, developing and middle income countries, suchas Brazil, are not immune. In the 1970s, undernutrition wasBrazil’s major nutritional problem, with only 5.7% of theadult population obese. Yet, between 2006 and 2009 adultobesity rates grew from 10.8 to 13.5%. The escalation ofobesity rates is rapid, but recent: an emerging epidemic.Many low and middle income countries now bear the‘‘double burden’’ of both obesity and undernutrition(Swinburn et al. 2011), increasing the complexity of bothproblems and solutions.Popkin and Gordon-Larsen (2004) described the nutri-tion transition and its global implications for obesity.Simply stated, most populations historically progressthrough a series of transitions that correspond to changes ineconomic growth, urbanization and culture. Most pertinentto obesity are the progressions from unstable and inade-quate traditional food supplies in Stage 3, throughincreased energy-dense processed foods high in sugars andfats accompanied by decreased physical activity in Stage4—a stage accompanied by increases in non-communica-ble diseases—to Stage 5, in which behavioral changeenables individuals to reverse the negative changes in dietand activity to delay and prevent non-communicable dis-eases. Relevant to obesity, the last decade has seen a rapidrate of transition from Stage 3 to 4 among low and middleincome countries, which has contributed to obesity as aglobal problem. The health and economic implications fordeveloping countries of following the same obesity tra-jectory set by countries such as the USA are grave, withsignificant costs to strained budgets. The question arises:Are emerging epidemics inevitable, or have we learnedlessons that may help prevent developing countries fromsuffering our fate?Thedeterminantsofobesityincludeindividualbehavioraldeterminants (diet and physical inactivity), environmentaldeterminants (e.g., economic access to healthy food andphysical activity opportunities) as the context for behaviorand social determinants (cultural, economic and political)thatfunctionatsocietallevels(Raine2004).Yet,thefirstlineof defense in public health often emphasizes education, suchas Moura and Claro’s (in this issue) concluding clause rec-ommending, ‘‘most importantly, education campaigns aboutthe importance of maintaining a healthy lifestyle’’. Whilethey also recommend changes to the environment to supportsuch behaviors, there appears to be an assumption thateducation may hasten the transition to Stage 5 where indi-viduals are empowered to improve their behaviors, reduceobesity, and ultimately their risk of non-communicabledisease. But, lessons learned from industrialized nationssuggest that a focus on individual behavior change isinsufficient to stem the rising tide of obesity. Addressing the‘‘upstream’’ environmental and social determinants of dietand activity behaviors is essential.Confronted with an emerging epidemic of obesity, it isessential that researchers, practitioners and policy makersrecognize that, ‘‘Obesity is the result of people respondingnormally to the obesogenic environments they find