It is only thermodynamically impossible if you assume 100% efficiency in energy extraction from food, but in practice we only extract a very small amount of energy from matter. Thermodynamically you could extract ~10^12 kcal from a Pop Tart if you converted its mass into energy.
Not that I agree that for a human metabolism meal timing makes much of a difference in energy extraction, but it wouldn't be thermodynamically impossible.
Not that I agree that for a human metabolism meal timing makes much of a difference in energy extraction, but it wouldn't be thermodynamically impossible.