|MadSci Network: Medicine|
First of all, it is important to remember that fat is an essential nutrient, so that we need to consume at least some of it. For example, for people who consume about 2,200 calories/day (about average), total daily fat intake should be between 49 and 86 g. That said, saturated fat should be less than 24 g per day for a 2,200 calorie diet. The reason for that is that foods do not only contain one type of fat. For example, lean beef contains 61% unsaturated fat and 39% saturated fat and corn oil has 86% unsaturated fat and 14% saturated fat.
The only other type of fats we should avoid are the added trans fats. These fats are produced during the partial hydrogenation of oils and will be listed on the nutrition ingredient list as "partially hydrogenated" oils. There are some naturally occurring trans fats, mostly from dairy products, that are not something we should avoid.
Reference: Roberta Larson Duyff American Dietetic Association. Complete Food and Nutrition Guide, 3rd edition. John Wiley and Sons. 2006.
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