Food products require significant amounts of energy and water throughout their lifecycle, yet humanity wastes 1.3e9 tons of food on a yearly basis. A large part of this waste occurs during the consumption (post-retail) phase of the food system as avoidable food waste, the discarded edible (parts of) food products. In this study, we explore the effects of avoidable food waste on the Food-Energy-Water nexus. We show that the 344 million tonnes of global avoidable food waste is responsible for squandering 4e18 J of energy and 82e9 m3 of water. While there are important regional differences in terms of avoidable food waste due to varying diets and waste incidences, these energy and water losses are rivaling the electricity and the blue water use of populous nations, and adding to needless pressures on the environment.