So what are healthy fats? See below and also the books by Enig/Fallon and Bruce Fife.
Data Below is From: Stop Alzheimer's Now! How to Prevent and Reverse Dementia, Parkinson's, ALS, Multiple Sclerosis and Other Neurodegenerative Disorders, Bruce Fife, N.D., pg. 246. Why Are Polyunsaturated Vegetable Oils Toxic? Also see Take the Fear Out of Eating Fat.
Margarine, Shortening, Hydrogenated Vegetable Oils.
What consumers don't know is that polyunsaturated vegetable oils [Corn, Canola, Soybean Oils, etc.] can be more harmful than saturated fats....You don't hear much about this because companies can't make money reporting and publicizing negative findings on their products...Polyunsaturated vegetable oils lower our resistance to infectious disease by depressing the immune system...One of the ways polyunsaturated fats hinder the immune system is by killing white blood cells [a primary component of our immune system]. It is our immune system that is our primary defense against cancer. It has been known for years that polyunsaturated fats promote the growth of cancer....The ability of high polyunsaturated fat diet enhancing chemically induced tumors has been widely reported.....Remove polyunsaturated fats and your risk of cancer plummets.
[The Palm Oil Miracle, Dr. Bruce Fife, pg. 32-33]
Heart disease [arterial plaque] has also been linked to polyunsaturated oils...Polyunsaturated vegetable oils that we use every day such as soybean oil, corn oil, safflower oil - as well as margarine and shortening - promote heart disease. Lineoleic acid, the primary fatty acid in these vegetable oils, increases inflammation, elevates blood pressure, and encourages blood clotting, all of which are risk factors for heart disease...When polyunsaturated fats oxidize [through heat], they become toxic. Oxidized fats are rancid fats....Heating polyunsaturated oils, as is typically done in cooking, oxidizes fats...These [polyunsaturated oils] are the fats that collect in artery walls.... All of the fats that collect in arterial plaque are oxidized.
[The Palm Oil Miracle, Dr. Bruce Fife, pg. 80-83]
In contrast, saturated fats are very resistant to oxidation...saturated fats are the safest to use for day-to-day cooking and baking...
[The Palm Oil Miracle, Dr. Bruce Fife, pg. 39]