Woodpecker, my girlfriend's family is from southwest France (Gascony), where they use plenty of duck and goose and pig fat with everything they eat (andouillette, foie gras, tripe, etc), and have very low rates of heart disease (5 times less than in North Am if memory serves).
Anyways, I've visited many Mediterannean countries, and you are absolutely right, their eating habits vary widely.
For example, in the South of Italy, they use olive oil aplenty, with pork fat (especially for homemade sausage and homemade pâtés, and sometimes to fry pasta), cheese, and very little butter. In Greece (again, depends on the specific region, but let's take Crete for example), they use butter, lots of cheese, lots of olives and olive oil, and fish. In Southeastern France, they use butter, sheep, pig, fish, and duck fat aplenty, but little olive oil.
And those are just the places where I've been, because there are many others. Even many Arab countries could be included in the Mediterannean diet, as could be Spain, and Corsica.
But the point is, no matter what region, these people consume plenty of fat, and almost always plenty of animal fat.
The diets that Keys saw in the 50s in Italy weren't the true diets of the countries he visited, they were the diets of the end of the war rationning.
If you don't believe me, go see for yourself! And those are magnificient regions, so you'll have fun too
