The plate half-full: Status of research on the mechanisms of dietary restriction in Drosophila melanogaster

► We review the analysis of Drosophila longevity extension by dietary restriction. ► Progress has been made to determine what quality of the diet regulates aging. ► Lifespan is extended by a high protein-to-carbohydrate ratio diet. ► Lifespan is not regulated by calories or energetic investment into reproduction. ► There are few good genetic data to study the mechanisms of dietary restriction.