Seed Oils Aren’t the Problem—How We Consume Them Is

Tufts Now: What makes seed oils like soybean, sunflower, canola, safflower, and corn different from other oils we may cook with or consume?

Alice H. Lichtenstein: Most seed or plant oils differ from other plant oils (coconut and palm oil) by the type of fatty acids they contain. Soybean, sunflower, canola, safflower, and corn oils, as well as olive and avocado oils, are rich in unsaturated fat.  Coconut and palm oils, as well as animal fats (meat and dairy), are rich in saturated fat. There’s a tremendous amount of data that has shown if you consume plant oils high in unsaturated fat opposed to coconut and palm oils or animal fats, there are better health outcomes. 

As far as soybean oil and canola oil, soybean oil is high in polyunsaturated fatty acids, and canola oil is high in monounsaturated fatty acids. They are unique among the common cooking oils because they’re also high in what’s called ALA, or alpha-linolenic acid, the plant form of omega-3 fatty acids. There are some advantages to using oils, but we also get omega-3 fatty acids from most types of fish, hence, the recommendation to eat at least two servings of fish per week. 

On a daily basis people should pick the type of plant oil that they’re going to use based on personal preference and intended use. For salad dressing, you might choose olive oil, for regular sauteing, soybean oil or canola oil are great. They’re affordable oils. If you’re making a stir-fry dish, you might also want to use a bit of sesame oil for flavor. But choosing one oil because you think it is better than others is splitting hairs. The real focus should be on using liquid plant oils as opposed to animal fat.