A very long time ago, I ceased “filling up” at a meal. At first, I ceased eating all the bread served in a restaurant, long before the main course arrives. People would stuff their faces with salad, bread, etc. I am paying for the steak, and I do not want to just take most of it home in a bag.
Eventually, at home or in a restaurant, I paid close at to that “oh man, I’m so full” feeling, and stopped before that point.
The one exception was my bicycle trips down the Kalifornia Coast. Some days I would get up early, ride for 2 hours, and then find the tallest stack of pancakes I could. Drowned the pancakes in maple syrup, and drank a lot of milk. For the first hour or so of bicycling after the LARGE meal, I was, indeed, uncomfortable. But the effort, the scenery, and the energy from the meal were worth it.
The year I reached 100 miles per day was unforgettable.