In an attempt to contain rising trends in obesity and associated chronic diseases, many governments have implemented a range of policies to promote healthy lifestyles. These efforts have been hindered by the limited availability of evidence about the effectiveness of interventions in changing lifestyles and reducing obesity.
Evaluations of the cost-effectiveness and distributional impacts of such interventions are even fewer and narrower in terms of numbers of options considered. An economic analysis was developed jointly by the OECD and the WHO with the aim of strengthening the existing evidence-base on the efficiency of interventions to tackle unhealthy diets and sedentary lifestyles. The analysis was broadly based on the WHO-CHOICE (CHOosing Interventions that are Cost-Effective) approach, and it aimed at assessing the efficiency of a range of policy options to tackle unhealthy lifestyles and related chronic diseases. Additionally, compared to the traditional CHOICE framework, the analysis assessed the distributional impacts of preventive strategies on costs and health outcomes.
Most of the preventive interventions evaluated as part of the project have favourable cost-effectiveness ratios, relative to a scenario in which no systematic prevention is undertaken and chronic diseases are treated once they emerge. However, since the determinants of obesity are multi-factorial and affect all age groups and social strata, interventions tackling individual determinants or narrowly targeted to one groups of individuals will have a limited impact at the population level, and will not reduce significantly the scale of the obesity problem.
Although the most efficient interventions are found to be outside the health sector, health care systems can have the largest impact on obesity and related chronic conditions by focusing on individuals at high risk. Interventions targeting younger age groups are unlikely to have significant health effects at the population level for many years. The cost-effectiveness profiles of such interventions may be favourable in the long-term, but remain unfavourable for several decades at the start of the interventions. Preventive interventions do not always generate reductions in health expenditure, when the costs of treating a set of diseases that are directly affected by diet, physical activity and obesity are considered.