Dopamine levels are stable so people need to eat a variety of foods

That's because when it comes to food,the brain evolved to pay special attention to new or different tastes.Why?Two reasons:first, to detect food that's gone bad.And second, because the more variety we have in our diet,the more likely we are to get all the nutrients we need.To keep that variety up,we need to be able to recognize a new food,and more importantly, we need to want to keep eating new foods.And that's why the dopamine levels off when a food becomes boring.