Olive Oil: The Fat That Keeps You Young and Healthy

If fats were fashion, olive oil would be the classic little black dress. It's the go-to fat of choice for heart-healthy chefs; it promotes the production of youth hormones, which keep you looking young and gorgeous; and with varieties like "Virgin" and "Extra Virgin," it's also the most provocative-sounding item in your cupboard. Here's why it's the Queen of Oilsand how to use it to your best advantage.

You know we don't hate fat—dietary fat. We're always telling you that 20 to 30 percent of your daily calories should come from the stuff. (See #3, above, in Steve's article.) You need it to transport essential vitamins like A, D, E, and K throughout your body, keep your skin supple, and cushion your organs, among other things. But you also know that fat is very high in calories. Oils are 100 percent fat. A tablespoon of oil has around 13 grams of fat. At 9 calories a gram, that's a whopping 120 calories per tablespoon.

Which is why you want to consume mostly good fats. Saturated fat is bad. Trans fat is very bad. Unsaturated fat? Good. Monounsaturated? Best of all. (Here's a hint to help you remember the bad ones: they have "t" as one of the first three letters—saTurated and Trans fatand "T," as the song goes, stands for trouble.) The oil with the most good fatmonounsaturatedis olive oil, good for you inside and out.

Heart healthy. Heart disease is the leading cause of death in this country for both men and women, but there are ways to reduce the risk. In addition to not smoking and getting plenty of exercise, we can also improve our diet to keep our arteries clear, our weight down, and our blood pressure low.

• Avoid saturated and trans fats. This goes a long way toward helping prevent fat deposits from accumulating on our artery walls. You've heard of "bad" cholesterol, LDL (low-density lipoprotein), and "good" cholesterol, HDL (high-density lipoprotein). HDL is good because it seems to protect against fatty tissue (plaque) accumulating in our arteries, while LDL increases that risk. The bad fats (saturated and trans fat) increase the level of "bad" cholesterol in our blood and decrease the level of "good" cholesterol. Even worse, most saturated fats are animal fats that also contain cholesterollike bacon drippings, butter, cheese, eggs, lardand we certainly don't need any more of that. Our bodies already make all the cholesterol we need.

  The majority of trans fat results from hydrogenation, in which hydrogen is added to liquid vegetable oils to turn them into solids at room temperature. It makes foods last longer and stabilizes their flavor (mostly commercial baked goods, like cookies, crackers, candy bars, and other snacks), but raises our LDL level, just as saturated fat does. We don't really know exactly how bad it is for us, but we do know the liver doesn't metabolize commercially produced trans fat the same way it does other fats. Manufacturers are now required to list trans fat on food labels, making it easier to avoid foods that contain it. (Check out Denis Faye's article on reading food labels and Steve Edwards' 911 focus on food labels for more information.)

  It's recommended that no more than 10 to 20 percent of our daily calories come from saturated fat—no more than 7 percent if you're already at risk for heart disease. And it's best just to avoid trans fat altogether!

• Choose unsaturated fats. Fat from plants tends to be liquid and unsaturated (except for tropical oils like coconut and palm kernelthose are saturated fats). The two types of unsaturated fat are polyunsaturated and monounsaturated. Both are good insofar as they lower the level of LDL, or "bad" cholesterol in the blood, but polyunsaturated fat also lowers HDL levels, the "good" cholesterol. Monounsaturated fat, on the other hand, lowers the bad cholesterol and increases the good kind. Nuts, seeds, oily fish, veggies, and olives are all good sources.

  Here's a list of some common oils and how they stack up against butter and margarine—olive oil is highest in heart-healthy monounsaturated fat:

Elixir of youth. Fat also plays a role in regulating hormones, including the so-called "youth" hormones that promote the body's ability to repair and regenerate cells. The production of these hormones starts declining in our 20s, and goes down 10 percent every decade from there, leaving cells at the mercy of free radicals, which hasten cellular breakdown. A diet loaded with saturated fat decreases the production of youth hormones even more, as saturated fat increases stress levels, causing insulin to spike, which inhibits the release of growth hormones.

Reducing stress and "bad" cholesterol through dietary changesnamely, cutting down on saturated fatwon't magically turn back the clock and make you look like Scarlett Johansson or Wentworth Miller, but it will make it easier for your body to produce youth hormones and stand up to those free radicals.

Increasing your level of HDL cholesterol is also key to producing more youth hormones. We already know olive oil is best at raising good cholesterol, but it's also rich in antioxidants (vitamin E and polyphenols), which fight free radical damage and have anti-inflammation properties as well. The "Mediterranean diet" is no fluke. People who eat olive oil as a dietary staple in addition to fish rich in omega-3 fatty acids, and lots of fruits and vegetables and breads and other cereals have a much lower rate of heart disease and live longer than people who consume lots of saturated fat.

So which kind of olive oil should you use? Extra virgin. It comes from the first pressing of the olives and so retains the most benefits. "Virgin" olive oil comes from the second pressing, so is less flavorful. "Refined" means chemicals were used. "Pure" olive oil is actually a blend of virgin and refined oil, while "Extra Light," though it sounds healthy, is heavily processed, and so has the weakest olive flavor and fewest benefits.

If you're going to cook with it, it probably doesn't matter much if you use virgin or extra virgin olive oil, as heat will damage the flavor of extra virgin anyway. (Hint: It's best to spray the oil on the pan instead of pouring it, as you'll use less.) But if you're going to sprinkle oil on salads or use it in marinades, go with extra virgin.

And be sure to store it in a cool, dry place, as it's volatile and can go bad if left exposed to heat and air. You can even store olive oil in the refrigerator if you wantbut that will make it cloudy and solidify, so before you use it, run it under warm water or allow it to liquefy at room temperature first.

Just remember: olive oil has about 120 calories per tablespoon, the same as any other oil. It has many benefits and is way better for you than any other fat, but it's a fat. So go easy!