Do Polyunsaturated Oils Lower Cholesterol?

Cholesterol is a waxy substance your body needs to produce hormones, digest food and create vitamin D. When you have too much cholesterol in your bloodstream, however, the excess combines with triglyceride fats to create rigid plaques on the inside of arteries. Over time, your heart receives less oxygen and nutrients, and you develop coronary heart disease, or CHD. Smart dietary choices can help lower your cholesterol levels and reduce your risk factors for CHD and heart attack.

Identification

Cholesterol's fatty consistency prevents it from dissolving in your blood, so it attaches to carriers known as lipoproteins. Low-density lipoproteins, or LDL, are the "bad" cholesterol, while high-density lipoproteins, or HDL, are the "good" cholesterol. Total cholesterol reflects your levels of HDL, LDL, triglyceride fats and Lp(a) cholesterol, a genetic variation of LDL. About 25 percent of the cholesterol in your body comes from the foods you eat, while the remaining 75 percent is produced in your liver and other body cells. When you opt for a diet high in cholesterol, saturated fats and trans fats, you increase the level of LDL and total cholesterol in your body.

Prevention/Solution

The therapeutic lifestyle changes, or TLC, diet developed by the National Heart, Lung and Blood Institute outlines the type and amount of fats you should eat to improve your cholesterol levels. These include limiting your daily fat intake to less than 25 to 35 percent of daily calories, restricting saturated fats to less than 7 percent of your calories, keeping trans fat intake below 1 percent and reducing your cholesterol intake to less than 300 mg daily. The remainder of your fat intake should be from healthier monounsaturated and polyunsaturated fats.

Effects

Polyunsaturated fats play an important role in removing newly-formed cholesterol from your body, and they limit plaque formation in your coronary arteries, notes the American Heart Association. When you replace saturated and trans fats with polyunsaturated fats, you can reduce both your LDL and your total cholesterol levels.

Sources

Polyunsaturated fats and oils are found in nuts and seeds, as well as oils made from safflower, sesame, corn, soy and sunflower seeds. A type of polyunsaturated fat, known as omega-3 fatty acids, is plentiful in fatty cold-water fish, such as salmon, mackerel, lake trout and herring. Flax seeds, flax oil and walnuts are particularly high in omega-3 fatty acids.

Expert Insight

Omega-3 fatty acids are so beneficial that the American Heart Association recommends eating at least two 3.5-oz servings of oily fish and a minimum of four servings of nuts, legumes or seeds a week to improve your cardiovascular health.