Preventive strategies against weight gain and obesity

A well-resourced, comprehensive, population-based set of strategies is needed to<br />attenuate and eventually reverse the current trends of increasing obesity prevalence<br />now apparent in most countries. The Epidemiological Triad (host, vector,<br />environment) has proven to be a robust model for other epidemics and is applied<br />to obesity. Host-based strategies are primarily educational and these tend to<br />be most effective among people with higher incomes and higher educational<br />attainment. The main vectors for a high-energy intake are energy-dense foods and<br />drinks and large portion sizes and, for low energy expenditure, machines that<br />promote physical inactivity. Vector-based strategies that alter food formulation<br />can have a significant impact, particularly through influencing common, highvolume<br />foods. The increasingly ‘obesogenic’ environments are probably the main<br />driving forces for the obesity epidemic. There are many environmental strategies<br />that can influence the physical, economic, policy or socio-cultural environments,<br />but the evidence base for these potentially powerful interventions is small.<br />Children should be the priority population for interventions, and improving the<br />general socio-economic conditions for disadvantaged, marginalized or poor population<br />sectors is also a central strategy for obesity prevention. The key settings<br />for interventions are schools, homes, neighbourhoods, primary health care services<br />and communities. The key macroenvironments for interventions are the<br />transport and infrastructure sector, the media and the food sector.