Three Kinds of Fat
For nutrition purposes, fats are devided into three categories: saturated, monounsaturated and polyunsaturated fats.  These categories are based on the amount of hydrogen atoms in the fat molecule.
Saturated fat molecules have no room for any more hydrogen atoms.  All animal fats, such as those in meat, poultry, dairy products and eggs, are saturated.  Some are also high in cholseterol.  Palm and coconut oils, though they don't contain cholesterol, are also saturated, and may cause the body to produce higher levels of heart-damaging cholesterol.
Molecules of monounsaturated fats, such as olive, peanut and canola oils, have room for one more hydrogen atom.  Polyunsaturated facts, such as corn oil, have room for many more hydrogen atoms on a molecule.

Hydrogenation
Saturated fats are solid at room temperature.  When hydrogen atoms are added to mono- or polyunsaturated fats, they become more solid.  So if your favorite margarine lists partially hydrogenated vegetable oil as a primary ingredient, it  means  that hydrogen atoms have been added to the fat molecules.  Hydrogenated oils are no longer polyunsaturated because they have been chemically altered to maked them solid at room temperature.  That's why it's better to choose soft margarines that come in tubs rather than hard sticks.

Less Is Still Better
The evidence is not in on wheter monounsaturated or polyunsaturated fats actually reduce the risk of cardiovascular disease.  But most researchers advise limiting all fats to less than 30% of total calories, and avoiding saturated fats as much as possible.

Read the fool label to find out the fat and cholesterol content of the foods you buy.  Avoid foods that contain palm of coconut oil regardless of their claims to be "cholesterol-free".  Pass up recipes that feature large quantities of olive oil and claim to be good for your heart.

If you have heart disease, discuss your diet with your dotor.  Restricting fat calories to 20% or less of total calories has been shown to reverse blockage of the coronary arteries in many people.

Chocolate Bar
Watch Those Fats