Certain foods can be better than others, but the basic tenet "eat less than you need to power yourself" seems like it should be a consistent formula for anyone

Certain foods can be better than others, but the basic tenet "eat less than you need to power yourself" seems like it should be a consistent formula for anyone who adheres to the first law of thermodynamics. I (and presumably many others) have used it with notable success, so when I see a data point that suggests it's not a valid approach, I immediately question the validity of that data point.