The cafeteria diet as a tool for studies of thermogenesis.

The cafeteria diet involves feeding experimental animals a choice of palatable human food items to stimulate energy intake, and has been used extensively to study diet-induced thermogenesis. In a recent commentary Moore has argued that this feeding regime is inappropriate for such studies because the nutrient composition cannot be controlled, many of the effects seen are due to protein or nutrient deficiency and accurate measurements of energy intake are difficult to achieve. We argue that all of these criticisms can be overcome by careful use of the feeding regime and well-controlled experiments. Gross nutrient composition of cafeteria diets can be modified over a wide range, and such studies demonstrate that the effects of protein deficiency can be clearly dissociated from those of hyperphagia. There is no experimental evidence for nutritional deficiency in cafeteria-fed animals even over very long periods of time. Furthermore, the alternatives suggested by Moore, i.e., presenting sucrose solutions to drink or high fat diets, suffer the same drawbacks of altered and often uncontrolled nutrient intake and yet produce little or no increase in energy intake. Criticism of the cafeteria diet is not justified simply because of its misuse by nutritionally naive experimenters. The value and validity of this feeding regime is further supported by the enormous impact it has made on our understanding of energy balance regulation and thermogenesis.