[tharbert]

Your body secretes a hormone Leptin when it senses you've eaten enough. Many "fast eaters" will overeat because they out pace the release and subsequent uptake of the hormone in the brain.

As for those you who ate fast for various reasons, you didn't necessarily get a full plate of food. That's a far cry from folks who belly up to the buffet and have their third plate emptied before their coffee gets cold.