Clearing the air on whether seed oils are bad for you

To their many vocal detractors, they are referred to as "the hateful eight".

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Canola oil, corn oil, sunflower oil and other refined oils made from the seeds of certain plants have become lightning rods for wellness influencers - and some politicians.

Robert F. Kennedy Ir says Americans are being "unknowingly poisoned" by them.

Online forums, blogs and influencers say they are "toxic", "slowly killing you" and driving up rates of diabetes, obesity and other chronic diseases.

The claim that seed oils are ruining people's health is especially rankling to nutrition scientists, who see them as a big step forward from butter and lard.

Decades of research have shown that consuming seed oils is associated with better health, said Stanford University professor of medicine Christopher Gardner.

To suggest otherwise, he added, just undermines the science.

The New York Times asked scientists to help clear up the confusion about how these oils affect the body.

WHAT ARE SEED OILS?

Seed oils have become shorthand for refined plant-based vegetable oils. Technically, not all the "hateful eight" oils - which also include cottonseed, soya bean, safflower, grapeseed and rice bran oils - are made from seeds. Soya bean oil, for example, is made from a bean. And there are other seed oils, like sesame and flaxseed oils, that are not on that list.

All of these oils are composed mainly of unsaturated fats. Most of them are high in one type, omega-6 fatty acids, and low in another, omega-S fatty acids.