Good-For-You Fats!

Saturated fat and trans fat increase your risk of heart disease by raising blood cholesterol, especially LDL cholesterol, the type that promotes heart disease. Saturated and trans fats in the diet also boost the levels of triglycerides (another type of fat) in your blood. And even worse, trans fat lowers your levels of HDL cholesterol, the good cholesterol that helps protect against heart disease. But don’t switch back to butter if you’ve been using margarine. Instead, choose a heart-healthy margarine made with little or no trans fat or saturated fat. This research shows that it’s healthier to replace bad fats with good fats (poly- and monounsaturated fats and fish oil) than it is to cut back on all fats in your diet. That’s because simply reducing fats across the board lowers your healthy HDL cholesterol as well as the damaging LDL cholesterol. It’s like cutting down the whole tree just to get rid of some bad apples.

Ideally, you want to keep LDLs low and HDLs high, and that’s what the good fats help do. When you replace unhealthy saturated and trans fats with healthy monounsaturated and polyunsaturated fats, LDLs drop more than beneficial HDLs.

Other positive effects come specifically from omega-3 and omega-6 polyunsaturated fats, found in fish, many vegetable oils, and some nuts and seeds. These fats reduce triglycerides, prevent arrhythmias (abnormal heartbeats), lower blood pressure, and help prevent atherosclerosis. Omega-3s and omega-6s both reduce the risk of heart disease and stroke. Fish, in particular, appears to offer potent protection against the most common type of stroke — ischemic stroke, which is caused by blockages in the arteries to the brain. In 2002, the Health Professionals Follow-Up Study found that men who ate seafood as little as once a month were 43% less likely to have ischemic strokes than men who ate seafood less often. Women in the Nurses’ Health Study who ate fish were also less likely to get strokes than those who didn’t. Monounsaturated fats have not been shown to reduce the risk of heart disease, but they do lower LDLs, which means that they’re good for the heart. The liberal use of olive oil in Mediterranean countries contributes to the very low rates of heart disease there.

What does all this mean for you? To reduce your risk of heart disease, replace dangerous saturated fats and trans fats with beneficial polyunsaturated and monounsaturated fats.