Soybean oil is a good source of vitamin E and polyunsaturated fats. However, the refining process uses high heat and harsh chemical solvents and which may create volatile compounds and have negative health effects. The polyunsaturated fats in soybean oil can be unstable and oxidize to create harmful compounds when used in high-heat cooking, which it is often used for. While studies have shown mixed metabolic benefits and adverse effects of soybean oil, more human research is needed and study differences may account for these diverse outcomes, including the use of heated versus unheated soybean oil. In one animal study, heated soybean oil had a negative outcome that the unheated oil did not have in rats. Soybean oil is also GMO-derived.