How much energy is locked in the USA? Alternative metrics for characterising the magnitude of overweight and obesity derived from BRFSS 2010 data

Objectives: Four metrics to characterise population overweight are described. Methods: Behavioural Risk Factors Surveillance System data were used to estimate the weight the US population needed to lose to achieve a BMI <25. The metrics for population level overweight were total weight, total volume, total energy, and energy value. Results: About 144 million people in the US need to lose 2.4 million metric tonnes. The volume of fat is 2.6 billion litres - 1,038 Olympic size swimming pools. The energy in the fat would power 90,000 households for a year and is worth around 162 million dollars. Conclusions: Four confronting ways of talking about a national overweight and obesity are described. The value of the metrics remains to be tested.