Unpacking the science of seed oils
March 31, 2025
Seed oils are some of North America’s most widely consumed edible oils, owing to their nutritional benefits, versatility, and availability. However, there are contrasting opinions in the press and continued misinformation about seed oils on social media, which makes it challenging for consumers to separate conjecture from scientific consensus.
A recent peer-reviewed paper published in the British Journal of Nutrition represents a comprehensive summary of the evidence, which supports the overall health benefits of consuming seed oils rich in the omega-6 polyunsaturated fatty acid, linoleic acid.
We’ve asked two contributing authors to share their insights on scientific literature, alongside two registered dietitian nutritionists to comment on practical applications.
So, whether you’re counseling your patients or clients — or browsing your local supermarket or newsfeed — read on to confidently address frequently asked questions on seed oils.
Q: What does the research say about seed oil consumption?
"Seed oils, including soybean oil, contain unsaturated fatty acids like the omega-6 polyunsaturated fatty acid, linoleic acid. Diets rich in linoleic acid have been shown to exert numerous health benefits according to a new comprehensive peer-reviewed paper on the scientific literature coordinated by Soy Nutrition Institute Global (SNI Global). This data indicates that seed oils containing linoleic acid lower blood cholesterol levels and may increase insulin sensitivity without exerting any adverse effects such as increasing oxidative stress or inflammation." — Mark Messina, Ph.D., MS
Q: Do seed oils support heart health?
"Strong evidence suggests that seed oils may positively contribute to cardiovascular health and can be a beneficial part of a healthy diet. For example, linoleic acid found in soybean oil has been shown to have a favorable effect on both total cholesterol and LDL-cholesterol levels when used as a replacement for dietary saturated fat without adversely affecting HDL-cholesterol and triglycerides. Seed oils also contain varying amounts of monounsaturated fatty acids. Some evidence indicates that replacing saturated fatty acids with monounsaturated fatty acids may modestly improve blood pressure." — Kristina S. Petersen, Ph.D.
Q: Are seed oils suitable for all types of eating patterns?
"Yes! Seed oils can be part of any eating pattern. As a registered dietitian, I frequently field questions about seed oils based on concerns circulating on social media. I remind my patients (and my colleagues) to stick with the science to help them make well informed food decisions. Not only are these oils beneficial to our health, they’re an affordable and accessible option for ourselves and our patients or clients. Incorporating unsaturated fats into our diets delivers essential fatty acids that we need to consume, and the safety of these oils is fully supported by the evidence. Plus, the Dietary Guidelines for Americans encourages the replacement of saturated fats with unsaturated fats to support cardiovascular health." — Melissa Joy Dobbins, MS, RDN, CDCES
Q: Do seed oils impact other chronic diseases?
"Population studies show that higher intake of unsaturated fats may help reduce the risk of type 2 diabetes. For example, a meta-analysis including 102 clinical trials with over 4,000 adults found that replacing 5% of calories from saturated fat with unsaturated fats significantly lowered blood sugar levels and insulin resistance. Another study with over 200,000 U.S. men and women, showed that dietary linoleic acid intake was significantly inversely related to risk of incident Type 2 Diabetes Mellitus over the nearly 3-decade follow-up period. All in all, studies suggest that eating more unsaturated fats, especially polyunsaturated fatty acids, may help manage and reduce the risk of developing type 2 diabetes." — Kristina S. Petersen, Ph.D.
Q: Which seed oils are best to grab at the store and how do you use them?
"Given there is much versatility among seed oils, it’s good to educate your patient or clients on how to pick the right one. Aside from the fatty acid composition, choosing the best oil will depend on the taste profile and the desired culinary application, especially when it comes to the smoke point. Cooking oils beyond their smoke point can lead to the formation of compounds that cause off flavors. For example, soybean oil’s smoke point is 450 degrees F while canola oil is 435 degrees F and corn oil is 410 degrees F, so it’s important to be mindful of that when choosing which oil to use. Soybean oil has a neutral taste, which means it won’t impact the overall flavor profile of the food being heated or prepared. Seed oils like soybean and canola are great for sautéing or grilling veggies, creating dressings for salads and sandwiches, and baking your favorite treats. Corn, canola, and soybean oils all fall into the ideal stovetop frying temperature of 350-375 degrees F." — Pam Smith, RDN
To learn more about the science on seed oils, visit SNIGlobal.org/seedoils
Seed oils are a subset of vegetable oils that are derived from seeds rather than the fruit of plants. These include canola, corn, cottonseed, grapeseed, rice, safflower, sesame, and soybean. While the composition of different seed oils may vary, they are all relatively high in unsaturated fatty acids and low in saturated fatty acids.
Information courtesy of the Soy Nutrition Institute
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