Study examining effects of poor nutrition during pregnancy and lactation in a primate lacks translatability.

We agree with Litwak and Levin that clinical trials are the best way to determine human health effects of dietary components. However, nonhuman primates offer experimental control and an anatomically and physiologically representative animal model and have inherent value in translational research. Details regarding study methodology are available on request, as they were at the time of review. Studies were conducted appropriately with regard to animal selection, known caloric intakes, and comparable dietary volume (our Table 1: caloric density was only 5% different). Species were not collapsed in any statistical analyses, because study 1 was conducted in cynomolgus macaques and study 2 in African green monkeys. Both species showed liver pathology with consumption of the same diet, which upholds the commonality in primate physiology that imparts value to dietary studies in monkeys. We believe that our results indicate that microbial translocation is an understudied factor in the epidemic of fatty liver and that the role of fructose deserves further investigation.