Calorie Mismeasurement in Past and Present Human Diets

Food-processing is a human cultural universal whose positive effect for net energy acquisition has been increasingly clearly documented thanks particularly to the use of animal model systems and ileostomy patients. A critical next challenge is the quantification of energy consequences from food processing. This is important for research on human evolution because evolutionary success depends crucially on the ability to acquire energy, as numerous studies show, which means that food-processing represents a potentially major adaptive leap contributing to individual fitness gain. Quantifying the consequences of food-processing therefore helps to distinguish its effects from increased meat in the diet. Quantification of net energy gain is similarly critical in order to achieve an effective food-labeling system, given that currently the standard method for determining dietary energy value (the Atwater system) systematically over-estimates the energy gain that is derived from relatively unprocessed foods.