Food & Recipes

What's in Your Olive Oil?

Olive oil is touted for its health benefits in many diet books and recipes. But is it really the nectar of the gods that it’s made out to be -- and is the olive oil in your pantry as healthy as you think it is?

In his book Extra Virginity: The Sublime and Scandalous World of Olive Oil, author Tom Mueller claims that much of the olive oil sold in the U.S. as "extra-virgin" is really adulterated in some way and lacks the health and the taste benefits of real “extra virgin” olive oil.

So what can you believe, and what's hype? Here are answers.

What Makes a Good Olive Oil?

Olive oils are graded based on their extraction process and on the acidity of the pressed oil, says Timothy Harlan, MD, assistant professor of clinical medicine at Tulane University and the author of Just Tell Me What To Eat! A former restaurateur, Harlan runs the web site DrGourmet.com.

True extra virgin olive oil -- or "EVOO" as TV's Rachael Ray calls it -- is extracted from olives using only pressure, a process known as cold pressing. "Extra virgin olive oil has just 1% acid. It is the oil that comes from the first pressing of the olives, and is considered the finest, having the freshest, fruitiest flavor," Harlan says. "Virgin olive oil also comes from the first pressing, and has about 3% acid."

Olive oil labels sport many other designations as well.

• Fino: a blend of extra virgin and virgin oil
• Light: an oil that has been filtered to remove much of the sediment ("Light," in this case, has nothing to do with fat or calories. It only refers to color.)
• Pure: a combination of refined virgin and extra virgin oils

Unfortunately, you can’t always rely on those labels. The U.S. government doesn’t regulate the labeling of extra virgin olive oil, says Ruth Mercurio, a board member of the California Olive Oil Council (COOC) and managing partner of We Olive, LLC, a specialty retailer offering only true extra-virgin oils from about 200 California growers.

"With no regulation in the U.S. regarding the labeling of extra virgin olive oil, many imported -- as well as domestic -- olive oils claim to be virgin olive oils, 'extra extra' virgin olive oil, or light extra virgin olive oil, but they don't in fact meet the standards of a true extra virgin olive oil," Mercurio tells WebMD in an email.

There are other pitfalls as well, Mercurio adds:

• No harvest date on the label means you run the risk of purchasing an old, possibly rancid oil. (True EVOO has a shelf life of only 18-24 months.)
• If the label says "Packaged in [name of a country]" (such as Spain or Greece), then more than likely the oil wasn’t grown in that country, just bottled there to give it more cachet.