system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do we like unhealthy food so much? Shouldn't natural slection have forced us into liking things that make we live longer and healthier?
gpt
So, back in caveman days, sugar and fat and salt were very rare. We evolved to find them very tasty, so that we'd work hard to find those important, but rare foods. The problem is that it's only been in the past century that we've been able to get WAY more salt, or fat or sugar than we need. But our bodies are still in "We must get enough fat so we can survive the ice age and hunt mammoths!" and it takes millennia for evolution to have an effect.