Cooking with Olive Oil Healthy?

No. Raw oil is always healthier than cooked oil, and that's true whatever the type of oil, olive or other.

OK, so what does heating the oil do to it that makes it less healthy? I know that some quality is lost in heating (that is, the uncooked oil just tastes better) but what health benefits are lost?

I honestly don't know the details... but when we got our newborn we read a lot of books on nutrition and one important point was to give him raw oils - not cooked.

AFAIK heating/cooking any food (so including oil) breaks down its nutritional value.

Heating causes loss of available nutrients (as expected) contained in oils, including fat-soluble vitamins such as E and the phytonutrients that give oils their characteristic colors, smells and flavors.
 

Heating oils can cause formation of free radicals, highly reactive molecules that can damage the oil further by triggering unwanted oxidative reactions.

Formation of unwanted aromatic substances (such as polycyclic aromatic hydrocarbons or PAHs) in the oil that can increase our risk of chronic health issues including cancers.

Joe

Hello,
I think olive oil is good for health.In these days many kinds of olive oil is presents,all are good.so don't worry about it.just use freely.www.maldari.com/

 Fried Oil/  ?? You really can't use olive oil for deep or high temp pan frying, as the smoking point is to low. It would probably burn or ignite and cause a fire.

I used to fry with extra virgin oil when the kids were young, just because as i understood it, all cold-pressed oils are free of chemical additives that get modified under high heat conditions.  I never used a deep fryer, I did stuff like croquettes or potatoes or battered or breaded vegetables and stuff like that, in a frying pan with oil to cover.  I used high heat, the stuff seemed to brown easily and not to absorb too much fat, and it never ignited, ever.  I didn;t fry very often and i had a free supply from my inlaws who knew someone in the country who produced it.  
My understanding is that in cooking (not frying) the extra virgin oil is best, - it might lose something but doesn;t add anything harmful.  

I think the term "healthy" is interpreted in different ways.  Some use it to mean "you should do this because it makes you healthier" and others use it to mean "it isn;t harmful"
The Italian proverbial version of "what doesn't kill you makes you stronger" is "what doesn't kill you makes you fat" which, in the days of poverty and undernourishment that in Italy lasted till the 60s, was actually a good thing!  It meant healthy! 

I agree with guru - so avoid any high heat cooking with olive oil.  It degrades the oil and turns it into a much unhealthier product.  Save your olive oil for using raw, or for cooking at low temp.  I don't know about the costs where you are, but it is way too expensive here to use large amounts for shallow/ deep fryin, apart from the info above about smoke point.

I use olive oil for everything, even baking cakes sometimes.  The only time I use a different oil is for deep frying.  For that I use peanut oil.... but I throw in a little olive oil in there too.

Ha, i do that too now that I stopped using it straight, Koukovagia, i use peanut oil and add a little extra virgin, just because it seems right. 

I do stop short at baking with it, or any oil for that matter, since i way prefer butter.  But olive goes into everything else. 

I knew an Italian who had lived in the states for a while who asked me "Why do Americans use Crisco all the time?"
I told her they like to cook with it because it has no taste. 
She said "So why would you cook with something if it has no taste??!!"

Just a general question to anyone who knows.  Isn;t there a difference in chemical breakdown when the oil is cold-pressed?  Cold pressed oil is only filtered.  Hot pressed oil is washed with chemicals to remove the debris, and the traces of chemicals, as i understood it, are what is unhealthy when heated - they change with heat and produce toxic substances.  This is what i read somewhere.  Any scientists here who can answer with some real scientific knowledge?"

Also, how about clarified butter, what is the smoke point of that - is that ever used for frying?  Not intending to use it but am curious. 

 I thought you all could use this when deciding what to fry with. As you can see, you would be right on the edge using extra virgin olive for  some deep fat frying.
The following table presents smoke points of various fats:

Fat	Quality	Smoke Point
Almond oil		420°F	216°C
Avocado oil		520°F	271°C
Butter		350°F	177°C
Canola oil	Expeller Press	464°F	240°C
Canola oil	High Oleic	475°F	246°C
Canola oil	Refined	470°F	240°C
Coconut oil	Unrefined	350°F	177°C
Coconut oil	Refined	450°F	232°C
Corn oil	Unrefined	320°F	160°C
Corn oil	Refined	450°F	232°C
Cottonseed oil		420°F	216°C
Flax seed oil	Unrefined	225°F	107°C
Ghee (Indian Clarified Butter)		485°F	252°C
Grapeseed oil		420°F	216°C
Hazelnut oil		430°F	221°C
Hemp oil		330°F	165°C
Lard		370°F	182°C
Macadamia oil		413°F	210°C
Olive oil	Extra virgin	375°F	191°C
Olive oil	Virgin	420°F	216°C
Olive oil	Pomace	460°F	238°C
Olive oil	Extra light	468°F	242°C
Olive oil, high quality (low acidity)	Extra virgin	405°F	207°C
Palm oil	Difractionated	455°F	235°C[1]
Peanut oil	Unrefined	320°F	160°C
Peanut oil	Refined	450°F	232°C
Rice bran oil		490°F	254°C
Safflower oil	Unrefined	225°F	107°C
Safflower oil	Semirefined	320°F	160°C
Safflower oil	Refined	510°F	266°C
Sesame oil	Unrefined	350°F	177°C
Sesame oil	Semirefined	450°F	232°C
Soybean oil	Unrefined	320°F	160°C
Soybean oil	Semirefined	350°F	177°C
Soybean oil	Refined	450°F	232°C
Sunflower oil	Unrefined	225°F	107°C
Sunflower oil	Semirefined	450°F	232°C
Sunflower oil, high oleic	Unrefined	320°F	160°C
Sunflower oil	Refined	450°F	232°C
Tea seed oil		485°F	252°C
Vegetable shortening		360°F	182°C
Walnut oil	Unrefined	320°F	160°C
Walnut oil	Semirefined	400°F	204°C

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