You'll eat a bit more than that, either out of boredom or necessity - MREs were never meant for continuous use. They are meant to sustain you for short durations, three or four days. If you are the typical BAMF working outdoors ("heavy work") 4 a day might be day might be a better deal if you don't augment with grains, ramen, oatmeal etc. Years ago we went on a BP trip with some friends in the mountains - I was the only veteran, everyone else took (2) MRE's a day. I knew better! They friggin' half starved, psycho-logically. They are tasty, but..
Good information - thank you for the tip!