[vadansky]

>You can't create/add matter to your body from nothing

Sure you can, imagine two scenarios:

1. You eat 100 calories, and you have a 70 calorie deficit in your cells. 70 calories go to your cells to make ADP (this makes you feel full) and the extra 30 goes to fat.

2. You eat 100 calories of HFCS, it spikes your insulin and your body take 90 calories into fat FIRST and 10 calories into your cells to make ADP. You are still hungry because you have a 60 calorie deficit because your cells still lack ADP, you still feel tired and you got fatter.

It is fully possible to eat nothing but trash food that freaks your body out. The problem is for a lot of people we were though the wrong facts about nutrition, like "Fat is bad and (highly processed) carbs are good".

[laweijfmvo]

This ultimately does violate physics if your caloric output is the same in both scenarios. Maybe the HFCS makes you more tired/lazy like you said and that causes your output to drop dramatically, but then it's no longer the same comparison.