I disagree. Doing science involves a mix of observation and experimentation. A lot of diet recommendations often do both. They've observed eating habits of heal

I disagree. Doing science involves a mix of observation and experimentation. A lot of diet recommendations often do both. They've observed eating habits of healthy people over less healthy people, and then they've experimented by having a bunch of people try the diet, and after some years, they've observed again what was the effects. Some diets don't do that. They're sometimes based on a type of "that makes sense" intuition, like, our ancestors used to eat mostly meat, so we should eat like them. Or, this substance is known to absorb toxins, so obviously eating it will clear your bloodstream of them. These I admit aren't scientific. Though often those intuitive catch phrases are thrown on top of scientific dietary ideas as a way to convince people to it and sell a bunch of books and products.