I recently took it upon myself to research the origins of calories, macros, and all those things from nutrition science. https://blog.jumpycatapp.com/calorie-counting-weight-loss-hi...

In truth, science seems to be still very far from understanding the complexity of how our bodies process food.(One recurring constraint seems to be the difficulty in controlling for "real life eating").

Learning from "traditional" diets and cuisine might be the best practical way to go about eating healthy. A bit of a black hole approach, but practical for most people.