Hormones, fats and oils, and high glucose and sodium can only do bad to your internal feelings; increases depression, decreases motivation and s3x drive, and increases body fat, which then decreases ego, which increases depression further. Also, it doesn't usually fill you up the way you want it to; one quarter pounder from McDonalds is easy for most people to eat, but a quarter pound burger from a eat in diner will always fill you up more. =D