system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 why isn’t it sufficiently satisfying just to chew tasty (but unhealthy) food rather than also needing to swallow it in order to enjoy it fully?

In other words, we all eat food that tastes great but is unhealthy. The part that we like is chewing it and enjoying the taste in our mouths. It would be great to do only that and then just spit it out and then turn to less tasty food and swallow that for the health benefits. But our bodies seem to need us to also swallow the bad (tasty) food in order to be satisfied. Why is that?
gpt
Food tastes good to us as an incentive to eat it. Our bodies evolved this to make us eat food that is calories dense specifically for our (over) nutrition; our body is much more worried about starvation than obesity. So that appealing flavor is almost inherently tied to us actually swallowing the food, rather than spitting it back out.