One of the drawbacks of being in the public eye is that all your statements are there for posterity- in books, videos, TV shows, YouTube. So when your opinions evolve or change over the years, you've still got to contend with the fact that you've gone "on record" as saying something that might be a lot different from what you believe today.
For years and years I've been recommending extra virgin olive oil as a great oil to cook with because it stands up to heat, is heart healthy and has a lot of great stuff in it (from monounsaturated fat to the- probably more important- olive phenols).
But a sharp eyed reader of my blog (Xenia) recently commented that extra virgin olive oil was a delicate oil that would be damaged by heat. After all, "extra-virgin" means it's cold pressed- by definition, that means it wasn't exposed to high heat in processing. Why spend all that money for the nutrient-saving "extra virgin" processing if you're going to destroy it by heating?, she asked.
A fair question.
So I did some digging.
First thing I found is that the "smoke point" of extra virgin olive oil is all over the map, depending on which manufacturer's information you read. Some olive oil websites say it's 410-450 (very high) but some manufacturers say it's only in the 200's.
It actually has to do with the processing. One of the reasons for refining any oil is to increase the smoke point. (Unrefined oils have a lower smoke point in general.) Really good extra virgin olive oil could be as low as in the 200's, where as the much less nutritious highly processed oil could be in the mid 400's.
Now if you're using extra-virgin olive oil at low heat, or if you're adding it to foods right before the end of cooking, no problem. But if you're really turning up the heat, it's not such a great idea.
My go-to guy for all things oil is Fred Pescatore, MD who knows more about this than almost anyone. I asked him, and he agrees- don't overheat olive oil. Fred recommends higher heat cooking with macadamia nut oil, avocado oil or hazlenut oil all of which naturally have higher smoke points without having to be refined and all of which contain many healthful compounds.
I'd add to that list my own favorite for cooking, Barlean's extra-virgin coconut oil, which has a whole host of health properties that I covered in my book The 150 Healthiest Foods on Earth, not to mention that it's absolutely delicious.
So bottom line: I certainly wouldn't give up my extra virgin olive oil, which is a rich source of protective olive phenols.
But from now on, I'll think twice about turning up the heat too high and too long.