Is it med diet or low carb diet which improves heart health?

http://circ.ahajournals.org/cgi/content/meeting_abstract/124/21_MeetingAbstracts/A15253

Actually, the authors tried a low refined carb diet and showed improvements in glucose tolerance. Indeed what we call today med diet is far from the original med diet:
1/ med diet despite massive advertising is not olive oil but veggies with small amount of olive oil...
2/ med diet is not highly refined carb like bread pasta and so on but meat fish veggies roots and fruits...
3/ med diet is not corn and soy-fed animals but grass-fed ones...
4/ med diet is rich in fish and seafood...