5000 cherry tomatoes are (on average) 250 pounds or 114kg. That makes 28500 calories a day. Not only it is physically impossible to eat 250 pounds of tomato in a day, but the calories contained are also so absurd, you'd have to drink 3.5 liters of frickin' olive oil straight to get the same amount of calories. A human won't be able to survive that either. It doesn't matter if you purge what you eat, we are talking about enough tomatoes to fill 68 gallon jugs.
I know this is a silly manga, and I do enjoy reading it, but man, every time the author gets to tomatoes it becomes so hard to suspend my disbelief. Directly takes me out of the manga, so much so that I am actually writing this comment!