These are usually liquid oils of vegetable or plant origin. Polyunsaturated fats tend to lower overall blood cholesterol and LDL "bad" cholesterol, if these oils replace the saturated fats you are presently using. 

More recent studies suggest that polyunsaturated oils decrease HDL or "good cholesterol". It is recommended that monounsaturated fats be used to replace the polyunsaturated fats when cooking, baking etc. Remember, only replace DO NOT USE MORE!

Sources: safflower, sunflower, corn, soybean, cottonseed oil, and some margarines, mayonnaise (depending on oil used in making it), fish, almonds, hazel nuts, pecans, and sesame seeds.


Omega -3 fats are type of polyunsaturated fat. The very long chain Omega - 3 fats found in fish oils may lover blood triglycerides, another type of blood fat. the effect on blood cholesterol is still uncertain. Omega - 3 fats also inhibit platelet aggregation. Many people supplement their diets with fish oils like cod liver oil. dietitians are advising against this since concentrated forms of fish oils may contain toxic amounts of nutrients like vitamin A and may also contain concentrated forms of contaminants which may cause other undesirable health effects. 

If you want to increase the amount of Omega - 3 fat in your diet, try eating fish more often, two or three times a week.


These fats are of animal origin and are solid at room temperature. The streaking in red meat (marbling) and fat along the edges of meat are examples of saturated fats. The important exceptions are tropical plant oils (coconut, palm, and palm kernel) and hydrogenated fats (hard margarine, shortening). Hydrogenated fats start out liquid but are turned into solids through the manufacturing process. 

Saturated fats raise the total cholesterol and LDL - cholesterol level of the blood more than any other food in the diet.

Sources: butter, cream, shortening/lard, ice cream, whole milk, regular cheeses, coconut and palm oil, hydrogenated margarines, chocolate, coconut and fatty meats.


Trans fatty acids are fats form when vegetable oils are hydrogenated. Hydrogenation is the process that keeps liquid oil solid at room temperature. You do not know you are eating them because they are not listed on labels. Trans fatty acids come from partially hydrogenated vegetable oils which are found in most margarines, shortenings, some packaged cookies, crackers, snack foods and pastries, muffins, breaded and fried chicken and fish. They occur naturally in smaller quantities in milk and butter. 
Trans fatty acids act like saturated fats because they can increase blood cholesterol and LDL "bad" cholesterol. Some research shows that trans fatty acids may also lower HDL "good" cholesterol. 

The best way to avoid trans fatty acids is to limit foods containing hydrogenated oils.


These fats may help to LOWER LDL "bad" cholesterol and increase HDL "good" cholesterol. Use in moderation, as these fats still do contribute to excess calories. 

Sources: olive oil*, peanut oil, canola oil, peanuts, peanut butter

* olive oil has some antioxidants which may protect against heart disease.

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Our pages are created to provide medically accurate information that is intended to complement, not replace or substitute in any way the services of your physician. Any application of the recommendations set forth in the following pages is at the reader's discretion and sole risk. Before undergoing medical treatment, you should consult with your doctor, who can best assess your individual needs, symptoms and treatment.