"Doesn't happen in practise" probably didn't fully describe what I meant - i.e. on average across populations if you tell people to "just" change their drinks for diet drinks, it seems other parts of the diet compensate for the lost calories.

> All my food is measured out and counted beforehand.

That's great, but that is not representative of most people.

That's what personally I don't like about information like this.

How can I apply it to my own situation then I wonder?

It seems like rarely does information that applies to people in general ever seems to apply to me in a relevant way.