If nutritional elements of food and the consumer's ability to use them can determine an animal diet, we can expect that differences in digestive capacity between animals reflect their dietary breadth. Diet diversity in Neotropical frugivorous bats is based on core plant taxa that present different nutritional compositions and qualities. Sturnira bats eat fruits with high sugar concentration, while Artibeus species eat fruits with lower sugar content. In this study we investigated the intake sugar response of Sturnira ludovici and compare it with the intake response reported for Artibeus jamaicensis. Our results show that S. ludovici was unable to achieve compensatory feeding, ingesting twice the energy when feeding on the most concentrated solution with respect to the more diluted one. This finding suggests the existence of a physiological constraint limiting energy intake when this species feeds on low quality food. Intake response slope value for S. ludovici was lower than the one reported for A. jamaicensis, indicating that S. ludovici is less suited than A. jamaicensis to feed on food with low nutrient content. The role that a physiological limitation could have on the food intake of S. ludovici, and the ecological implications of our findings are discussed.