[pants2]

If you're comparing raw calories to output, yes. Even gasoline has a caloric value, but humans can't drink gasoline. Growing and preparing food for human consumption uses a lot more energy than pumping and refining gasoline, so at the end of the day, human efficiency gains are not that impressive.

[arximboldi]

that's a misleading equivalence because you're also not considering the energy it took to grow the plants that produce that oil millennia ago. perhaps comparing to biodiesel or alike would be better. but even then it underestimates the efficiency of the human body, because food contains not only the energy we use, but also the materials to build the body itself. so you'd need to account for the inputs into that biodiesel and then all the extraction of materials and production of the machine itself. biology is amazing

[pants2]

You also need to consider the energy released during the big bang as a prerequisite for creating that food and gasoline. The big bang released about 10^70 J of energy, roughly equivalent to eating 10^63 big macs