Healthy Oils, Healthy Fats: The ‘New’ Truth

Medically Reviewed by Laura J. Martin, MD on January 08, 2013
4 min read

It used to be widely accepted: Saturated fat is bad. But some studies suggest that saturated fats in moderation may not be so hard on your heart after all. What's more, replacing saturated fats with the wrong foods -- such as the refined carbohydrates in white bread, white rice, pastries, candies, and desserts -- may actually be risky.

Here are five ways to fit fats and oils into your heart-healthy diet.

Health experts told us to eat less saturated fat when they found that it raises LDL, the "bad" cholesterol. That advice made perfect sense. High LDL is linked to heart disease.

The focus on saturated fat alone may have been misguided. "We now know there are many other important [factors] for heart disease risk," says Dariush Mozaffarian, MD, of the Harvard School of Public Health.

When you look at all of the factors together, he says, saturated fat isn't as bad as once thought. Indeed, reviewing the evidence, Mozaffarian and his colleague Renata Micha found that levels of saturated fat have very little impact on heart-related risk.

Americans eat about 11.5% of calories from saturated fat. If we cut that roughly in half, to 6.5%, we might lower our risk of heart disease by only about 10%, Mozaffarian says.

But during the low-fat craze, many people replaced saturated fat with fat-free products that were high in refined carbohydrates. That switch may end up raising their risk for heart problems.

So can you eat as much butter and cheese as you like? No. The American Heart Association still recommends that no more than 7% of all your calories come from saturated fat, which is found mainly in fatty meats and dairy foods.

Most experts still agree that it's smart to swap out some saturated fats for unsaturated fats. Olive oil and canola oil are better choices than butter, for instance.

But there's plenty of debate about the healthiest type of oil.

Vegetable oils typically mix two types of fat: polyunsaturated and monounsaturated. Olive oil is mostly a monounsaturated fat. Corn and soybean oils are mostly polyunsaturated. Canola oil is unusual among vegetable oils because it has omega-3 fatty acids, like those found in fish oil.

You may want to use a variety of plant-based oils. That's good for cooking and flavor, as well.

Olive oil, with its rich flavor, is great for salad dressings, for drizzling over pasta, or for dipping bread. Peanut oil and sesame oil also have rich flavors. But all three of these oils smoke and lose flavor at high temperatures.

Canola and sunflower oils are better for cooking because they have high smoke points. Also, canola oil has very little flavor of its own, so it won't overwhelm other ingredients.

There's no debate about the need to get enough omega-3s. Found in fish oil, omega-3s protect against abnormal heart rhythms. They help keep blood vessels flexible, which lowers your risk for a heart attack or stroke.

Aim for at least two servings a week of a fatty fish such as salmon, sardines, lake trout, or albacore tuna.

Walnuts, flaxseed, and canola oil also offer omega-3s, though it's a less potent type. Supplements are another option: Ask your doctor first.

Skip artificial trans fat completely. It raises bad cholesterol and lowers good cholesterol. It can also boost inflammation, which is linked to heart disease, stroke, diabetes, and other chronic diseases.

"Fortunately, labeling requirements and bans on trans fats have dramatically limited their presence in food," says Janet de Jesus, RD, of the National Heart, Lung, and Blood Institute. But trans fats are still in some processed foods.

Also, know that if a product says it has "0" grams of trans fat per serving, it may actually have up to half a gram of trans fat per serving. That adds up. So check the ingredients list. "It's still wise to read labels and avoid foods that contain hydrogenated oils," de Jesus says.

Fats are an important part of a healthy diet, especially unsaturated fats. The Mediterranean diet gets 30% or more of its calories from fat. It's widely considered one of the healthiest eating patterns in the world. Much of the fat in the Mediterranean diet comes from olive and other plant-based oils, as well as from fish.

"It's a matter of perspective," Mozaffarian says. "With the focus on low-fat, we lost track of that. A good diet isn't about percentages of fatty acids, but about an overall healthy eating pattern." Eat a mix of fruits, vegetables, whole grains, fish, lean meats and poultry, and healthy fats for a balanced diet.