Oxygen because I would die in minutes if I didn't have it. Oh wait so would everyone else lol. But yeah not sure if oxygen is an object/thing, but whatever the case is I'll answer the question in the way that I think it is designed to be answered and that it regarding food, or at least I guess? I don't know I would say oxygen is consumed the most out of all the essentials human beings need, but that's just a guess and not based on any facts.
Anyways, back to the question, the food I consume the most is probably pasta cause I have lots of different types of it quite frequently.