gluttony leads to laziness. if you stuff your face then you will not be at your best. when you stuff yourself you need to rest. if you are stuffed all the time then you will rest more. your mind and body will go into lazy-mode.

there used to be a lot of starvation in human populations. those that could survive periods of famine went on to breed and create the next generation. the special ability that they had to survive famine was their gluttonous behavior and their ability to get fat. if there was food available they would eat it and keep on eating it until there was none and eating so much food made them fat. when a period of famine arrived, the fat ones were able to last until food was plentiful again while the skinny or non-gluttonous ones died off.

after eating a big meal, you need rest because digestion needs to take place. the more food, the longer the digestion period obviously. you'll get cramps if you try and exert yourself too soon after eating because your blood flow has shifted more to your digestive system for it to do its work. so obviously, the more you stuff yourself, the more you will need to rest. you will feel lazy in both mind and body.

in order to avoid gluttony induced laziness you need to eat smaller meals which are broken up throughout the day so that you are not eating so much at a single meal and you can't stuff yourself at any of them.