Americans continue to get heavier. Most weight control methods short of bariatric surgery are generally considered ineffective in preventing obesity or reducing weight. The term energy gap was coined to estimate the change in energy balance (intake and expenditure) behaviors required to achieve and sustain reduced body weight outcomes in individuals and populations. In a commentary published in the November 2009 issue of the Journal of the American Dietetic Association, researchers more precisely clarify the concept of the energy gap (or energy gaps) and discuss how the concept can be properly used as a tool to help understand and address obesity. Investigators from the University of Colorado Denver and the Procter & Gamble Company, Mason, OH, discuss the two key factors related to the energy gap concept: prevention of excess weight gain and maintenance of achieved weight loss. It is estimated that the energy gap for prevention of weight gain among those who have lost weight is about 100 kcal/day in adults and 100-150 kcal/day in children and adolescents. Any combination of increased energy expenditure and decreased energy intake of 100 kcal per day in adults and 100-150 kcal/day for children and adolescents could theoretically prevent weight regain in 90% of the US population. This suggests that this small changes approach could be very effective for preventing excessive weight gain in adults and children. The energy gap to maintain weight loss is generally much larger, amounting to 200 kcal/day for a 100 kg person losing 10% of body weight or 300 kcal/day for the same person losing 15% of body weight.
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