Soybean oil is the most widely consumed oil globally and in the United States, as it accounts for approximately 30%1 and 57%2 of total edible oil consumption, respectively. It also accounts for more than 7% of U.S. total caloric intake and more than 40% of the intake of both essential fatty acids, linoleic acid, an omega-6 fatty acid and alpha-linolenic acid, an omega-3 fatty acid.3
Soybean oil is comprised of approximately 58% polyunsaturated fat, 23% monounsaturated fat, and 16% saturated fat (table 1). Replacement of saturated fat with unsaturated fat, like is found in soybean oil, improves circulating lipids and lipoprotein levels, the main targets for cardiovascular disease prevention and management. The first clinical trial demonstrating the cholesterol-lowering effect of soybean oil was published in 1993.4 Several other trials have subsequently been published.5-11
This cholesterol-lowering replacement effect of soybean oil was formally recognized by the U.S. Food and Drug Administration (FDA) in 2017, when it approved a qualified health claim for soybean oil and coronary heart disease.12 Language allowed by the FDA in support of the soy oil health claim is much stronger than allowed for other oils with approved health claims, including canola oil and olive oil. The claim states:
“Supportive but not conclusive scientific evidence suggests that eating about 1½ tablespoons (20.5 grams) daily of soybean oil, which contains unsaturated fat, may reduce the risk of coronary heart disease. To achieve this possible benefit, soybean oil is to replace saturated fat and not increase the total number of calories you eat in a day.”
Despite the favorable fatty acid profile and the FDA health claim, the results of a small number of animal studies conducted by UC Riverside researchers have raised concerns about the healthfulness of soybean oil.13-15 While animal studies are part of the scientific literature, they carry much less weight within the scientific community than human studies do. Findings from animal studies are generally used for hypothesis generation, not as a basis for reaching conclusions about health effects in humans. In contrast to the aforementioned animal studies, observational studies and clinical studies support the safety and health benefits of soybean oil. Concerns that have been raised about soybean oil are addressed individually below.