If I asked you what “good food” is, I can guarantee that your answers would be different to those of people in other times and places. But human physiology doesn’t vary that much – why would good food for you be bad food for me? Clearly there are some people with allergies or other intolerances who have to avoid certain foods, but that’s a given.
Consider the humble cabbage. Not many people get excited about cabbage, despite it being highly nutritious and very cheap. If you’re an Anglo Australian, there are too many associations with boring old British food, and it smells sort of funny too. Definitely not a cool vegetable, like kale.
However if you ask my Korean friend, she’ll tell you that cabbage is a staple in her diet and is considered to be a foundation of Korean food. It’s important in her culture and highly valued. Her family eats several heads of cabbage per week.
What does she look down on? Potatoes and sweet potatoes! They’re cheap, easy to grow vegetables that fill you up – in other words, poor people’s food. Compare that with the paleo/crossfit crowd who can’t get enough of sweet potatoes in particular due to their relatively dilute carbohydrate component and high micronutrient content.
None of these foods changed from place to place – a Korean potato is much like an Australian potato, just as Korean people and Australian people are basically the same physiologically. The difference is fashion, or as we like to call it, culture. Rich people (us) don’t like to be seen eating “poor people’s food”, and connotations of certain foods vary drastically from culture to culture.
The ultimate irony: kale and cabbage are virtually the same plant and have very similar nutritional profiles having, along with brocolli, cauliflower and Brussels sprouts been bred from an ancient ancestor.
But you can’t go down to Boost juice to get a cabbage smoothie.