Now, the sane advice is that salt and fat are not bad for you, but are essential to life and enjoyment. Of course margarine and all that other artificial, substitute crap turned out to be way more detrimental to us. A good amount of fat (and carbs) causes food to taste good and also be satisfying: you can pound a package full of rice cakes, or a giant salad and not feel full, unless you accompany it with butter or oil.
Julia Childs and French people couldn't be wrong: they consume plenty of rich food and they don't have American health problems. This may be a canard, but it's true that the FDA/USDA doesn't actually advocate for consumer health; just look at the ridiculous "food group" "food pyramid" propaganda they keep sending us.
Today at home I am unapologetically natural, and I love organic food. I use organic whole un-homogenized milk. I use Kerrygold unsalted. I also use Himalayan pink salt, because table salt has no nutritional value (all the nutrition is refined away and sold to supplement companies!)
Conventional wisdom about food is often dead wrong, but if you sift through all the fad diets and bogus medical advice, you can sometimes find nuggets of truth.