The oils Americans eat include animal fats and vegetable oils. The main animal fat is butter, which is what Shanghainese people often refer to as white butter, which is actually the phonetic translation of butter. Some places in the South eat lard, but this is not common elsewhere in the United States. Americans eat a lot of vegetable oils, including palm oil and olive oil. A few of the more common oils: soybean oil, canola oil, corn oil, and cottonseed oil, can be genetically modified, as most of these crops are genetically modified.

Palm oil is mainly used for frying, such as the frying oil for instant noodles. The advantage of palm oil is that it is more stable and less prone to spoilage, but it is too high in saturated fatty acids, which is bad for health. Another kind of oil for frying is hydrogenated vegetable oil, hydrogenated from canola oil, soybean oil and so on. In the past, trans fatty acids were formed during the hydrogenation process, which was more harmful to the human body. Later, the Americans improved the process to minimize the production of trans fatty acids. 2005 U.S. legislation requires that foods containing more than 0.5 grams of trans fat per serving must be labeled as to their content.

Corn oil is a very common oil in the United States because of its high smoke point, which makes it great for stir-frying and no other flavor distractions. Corn oil is more stable, than other oils have a longer shelf life, suitable for cooking and frying and frying oil, it can maintain the color and flavor of vegetables and food, without loss of nutritional value. 84% of the corn in the United States is genetically modified (GM) corn that has been transferred into the Bt protein (an insect neurotoxin protein). While most of the GM proteins are present in the corn leaves and endosperm in the form of proteins, there should be no more GM ingredients in the oil. So in American supermarkets, this oil doesn't have to be labeled out and is sold mixed with other non-GMO oils.