Extra virgin olive oil (EVOO) is considered by many nutritionists a medicine by itself, with its polyphenols it is a protective food from many ailments. Besides, it makes the veggies taste better and fills you up staving off hunger.
If it is of good quality, 2-3 tablespoons and more is not much. Watch out though, I know that in America frauds are common, especially when Italian EVOO is concerned. EVOO is a main ingredient of my own diet and I can testify to its many benefits.
The science of cooking with olive oil
http://www.truthinoliveoil.com/2013/10/science-cooking-olive-oil The Truth on Olive Oil Health
http://www.truthinoliveoil.com/2013/04/truth-on-olive-oil-health