Recently, several reports and media articles have noted that official statistics show a large decline in calorie consumption in the UK over the last 40 years. At the same time, we have seen the population gain weight over this period. How has weight gone up, if we are eating less?
One response is that physical activity levels must have declined, leading us to expend much less energy. But this conclusion is at odds with the consensus of expert opinion, which points to rising calorie intake as the main cause of obesity. This question has major policy implications: the two schools of thought imply different
approaches. One says that reducing calorie intake should be central to any obesity strategy; the other that calorie intake is falling without government activity, and therefore the rationale for policies aimed at reducing consumption is weak.
This report concludes that it is not plausible that large falls in calorie consumption, offset by even greater falls in physical activity, have caused the rise in obesity. Instead, we propose that the apparent fall in consumption can be explained by an increase in underreporting of calorie intake in official statistics. In other words, calorie intake may not actually have declined.