Just went on a 3 hour ride last Saturday with my new garmin computer for the first time...upon arriving at my mother's house for dinner, I was slightly disappointed that she'd ordered an ultra greasy extra pepperoni pizza for dinner since I'm trying to eat healthy and lose a bit of weight.
Upon review of my workout on the spiffy computer though, I discovered I'd burned an estimated 3700 calories...Taking stock of the situation I figured I couldn't possibly eat HALF of what I'd just burned, so I proceeded to ingest 4 slices of the extra greasy gut bomb pizza, then a small bowl of pasta with olive oil about an hour later.
Normally this would have made me sick to my stomach, but as the night wore on I felt the same as if I had eaten steamed brown rice and salmon with vegetables.
Long story short, if you feel good after eating (1-3 hours later), you've probably eaten 'healthy'. If you feel stuffed/bloated/heavy/discontent, you've probably eaten 'unhealthy' ....that's how I look at it!