Also, if your body is attuned to a certain average intake, and you go WAY over it suddenly, you're not going to absorb 100% of all that extra food.  If you can tolerate the psychological grossness, there are infographics on how to look at your stool consistency and gauge how your body processed it.  And there is one for excess oils and fats. Pile in more bad food than your body can handle, and it'll pass it through. Make a habit of it, and your stomach (intestines) will start secreting more of whatever it is breaks down oils.  But our takeaway is this - if you eat healthy all the time and overeat badly one time, your body will reject it - not hoard.  I can't believe how stupid everyone is in that entire thread.