Fats can be liquid (oils) or solid. They are formed from fatty acids, which are chains of carbon, hydrogen, and oxygen atoms. Your body needs a certain amount of fat to function. Without fats your body would be unable to make use of the vitamins you consume. Saturated, unsaturated, and polyunsaturated fat refers to the number of hydrogen atoms; saturated being the most and polyunsaturated the least. Too much saturated fat can lead to elevated LDL cholesterol (Low Density, "the bad one").

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