Obesity has risen dramatically in the past few decades. However, the relative contribution of energy intake and energy expenditure to rising obesity is not known. Moreover, the extent to which social and economic factors tip the energy balance is not well understood. This exploratory study estimates the relative contribution of increased caloric intake and reduced physical activity to obesity in developed countries using two methods of energy accounting. Results show that rising obesity is primarily the result of consuming more calories. We estimate multivariate regression models and use simulation analysis to explore technological and sociodemographic determinants of this dietary excess. Results indicate that the increase in caloric intake is associated with technological innovations as well as changing sociodemographic factors. This review offers useful insights to future research concerned with the etiology of obesity and suggests that obesity-related policies should focus on encouraging lower caloric intake.

中文翻译：

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为什么发达国家肥胖？

在过去的几十年中，肥胖症急剧增加。但是，能量摄入和能量消耗对肥胖症的相对贡献尚不清楚。此外，人们还不太了解社会和经济因素在多大程度上推动了能源平衡。这项探索性研究使用两种能量核算方法估算了发达国家热量摄入增加和体育活动减少对肥胖的相对影响。结果表明，肥胖的增加主要是由于摄入了更多的卡路里。我们估计多元回归模型，并使用模拟分析来探索饮食过量的技术和社会人口统计学决定因素。结果表明，热量摄入的增加与技术创新以及社会人口统计学因素的变化有关。