Why Soybean Oil May Not Be As Nutritious As You Think
Soybean oil is featured in a wide range of popular food products including margarine and shortening, salad dressings, and mayonnaise (per AgHires), and is often found in many baked goods such as cookies too, Bakerpedia notes. It is the main ingredient in most vegetable oils, and at 11.34 million metric tons, soybean oil is the most widely consumed edible oil in the U.S. (per Statista).
The United States produces the second-most soybeans in the world, Statista also notes, harvesting 4.44 billion bushels in 2021, according to the United States Department of Agriculture. Soybeans are big agribusiness, and as such they have received big government subsidies to the tune of $44.9 billion between the years of 1995-2020 (via Environmental Working Group).
There is a lot of incentive within the soybean industry to promote its benefits and downplay any negative aspects. Industry marketing campaigns often tout the benefits of soybeans and soybean-based products like soybean oil as being a good source of polyunsaturated fats that promote heart health and can lower the risk of cardiovascular disease, per Livestrong. It also contains the antioxidant Vitamin E, which is prized for its disease-fighting properties.
However, despite all of these purported positive qualities, some studies also link soybean oil to some undesirable ones.
Studies cast doubt on the nutritional benefits of soybean oil
A series of scientific studies conducted on soybean oil by a team at University of California – Riverside from 2015-20 citing research in lab mice indicate that soybean oil not only appears to be linked to diabetes and obesity, but may also impact neurological conditions such as depression, Alzheimer's, Parkinson's disease and anxiety, Science Daily reports. However, this research did not prove that soybean oil actually causes any of these aforementioned neurological conditions.
The authors of the research emphasized that the studies were done on mice, and soybean oil may impact humans differently. But their findings were sufficient enough for Science Daily to dispute the nutritiousness of soybean oil, writing "in all likelihood, it is not healthy for humans." While mentioning further investigation in the future into soybean oil's possible effects, one of the study's authors also contributes this ominous statement: "If there's one message I want people to take away, it's this: reduce consumption of soybean oil." Citing this research, the health and nutrition site Our Paleo Life even advises those on a low-carb diet with high fat content to avoid soybean oil completely.
If you're looking for some alternatives to use in lieu of soybean oil in your own kitchen, here's a primer on choosing the right cooking oil.