Data about food, and data about individuals’ purchases and consumption of food are becoming increasingly ubiquitous. Through bonus cards, supermarkets can track exactly which products we buy, through diet apps we can track what we eat, and through blockchains and other technologies producers can track the origin and history of individual products. From a technical point of view, we are not far away from a world where all this information could be combined to one omniscient system - OmniFood. In this paper we explore current possibilities to collect data on what products we buy, how environmental and nutritional data can be mapped to these products and possibilities to track what we actually eat. Next, we present a number of prototype systems where the possibilities to use this data has been explored, and what limitations we have encountered with current implementations and available data. We end with a discussion of some services that could be possible if current technologies would be fully implemented and made available to consumers and system developers. What possibilities could such systems offer for consumers who want to eat both sustainable and healthy food? What limitations would still exist? What ethical aspects would need to be considered? The focus is on using such a system as a decision support system to support consumers in making food purchase choices that are sustainable from both environmental and health perspectives, thereby supporting the global food system to stay within sustainable limits.