The oils Americans eat include animal fat and vegetable oil. The main animal fat is butter, which is commonly known as emulsified oil in Shanghai. Actually, it's a transliteration of Butter. Some places in the south eat pork suet, but it is not common in other parts of the United States. Americans eat a lot of vegetable oils, including palm oil and olive oil. Some common oils, such as soybean oil, rapeseed oil, corn oil and cottonseed oil, may all be genetically modified oils, because most of these crops are genetically modified.

Palm oil is mainly used for frying, such as frying instant noodles. Palm oil is relatively stable and not easy to deteriorate, but its saturated fatty acid content is too high, which is not good for health. Another frying oil is hydrogenated vegetable oil, which is hydrogenated from rapeseed oil and soybean oil. In the past, trans fatty acids were formed during hydrogenation, which was harmful to human body. Later, Americans improved the process to minimize the production of trans fatty acids. In 2005, American legislation stipulated that every food containing more than 0.5 grams of trans fat must be marked with its content.

Corn oil is a very common oil in America. Because of the high smoke point, it is very suitable for cooking, without other flavor interference. Corn oil is relatively stable and has a longer shelf life than other oils. Suitable for cooking and frying. It can keep the color and fragrance of vegetables and food without losing their nutritional value. 84% of corn in the United States is transgenic corn with Bt protein (an insect neurotoxin protein). Although most of the transgenic proteins exist in maize leaves and endosperm, and exist in the form of protein, there should be no transgenic components in the oil. Therefore, in American supermarkets, this oil does not need to be labeled, and it is sold together with other non-genetically modified oils.