Fats are categorized by the proportion of fatty acids in them. For example: Sunflower oil is categorized as unsaturated because it has a greater percentage of polyunsaturated and monounsaturated fatty acids than it does saturated.
The liquid or unsaturated fats can be made more solid by a process called hydrogenation which adds hydrogen atoms to some of the double bonds in the unsaturated fatty acids. This process turns liquid oil into a solid form, making it more saturated, as in the process of making margarine.
Fats and oils are all about the same in caloric content. It is recommended that you reduce your total fat intake to 30 percent or less of your total calories. 1/3 saturated, 1/3 monounsaturated, and 1/3 polyunsaturated.
some content from: Harcourt Learning Direct and the American Heart Association
categories of common fats
Saturated Fats
These fats are of animal origin. They are solid at room temperature and may tend to increase blood cholesterol levels.
