Why do we have the sense of taste? Why do some things taste good and some don't?
Human beings, like other animals, have developed over time through a process of natural selection. As it turns out, taste is a method of measuring a food's edibility (nutritional content, digestibility, and bio-availability of nutrients). The humans whose sense of taste pointed them towards the best health-promoting foods ended up living longer/stronger and propagating more abundantly.
Ever wonder why a baby puts everything in its mouth? Its testing out if its food.
What are some tastes that every human being on the planet identifies with as "tasty"? Sweet and juicy - fresh fruits. We're wired to get hooked on fruits.
Makes you think - is it worth eating "health foods" that don't even taste good?