What are seed oils? What you need to know about the food group deemed the 'hateful eight'

If you've heard about seed oils, it was probably within the context that they aren't the best for you.

Last year, several restaurant chains announced they would move away from using seed oils. Sweetgreen switched to only using olive oil. Shake Shack ditched soybean oil. Texas-based Hopdoddy became the first burger chain to go seed oil-free. You can now find specific condiments and sauces that are without seed oils.

Does that mean you need to be afraid of consuming seed oils? Here's what nutrition experts want you to know.

What are seed oils? 

Seed oils include canola, corn, cottonseed, grapeseed, soybean, sunflower, rice bran and peanut oils. This group is sometimes referred to as the "hateful eight" and blamed for a whole host of health problems.

But nutrition experts have pushed back on these claims, arguing that there isn't enough research to put the blame on seed oils. They're mostly used to cook fried foods higher in other ingredients that can have negative health impacts if consumed at high quantities over time.

"Seed oils are typically high in omega-6, which on their own are not inherently inflammatory," registered dietitian Caroline Thomason tells USA TODAY. But, she adds, "most Americans already consume enough omega-6s and do not get enough of omega-3 fatty acids. This imbalance of too many omega-6 fatty acids and too few omega-3 fatty acids is the bigger problem at play here."

When it comes to consuming seed oils, Thomason recommends high-oleic sunflower oil for a higher-quality option. "And make sure that you also get plenty of omega-3 in your diet by choosing fatty fish like salmon — Alaskan salmon has the highest omega-3 content — walnuts or chia seeds," she adds.

Is olive oil a seed oil? 

Some vegetable-based oils are also considered part of the seed oil family if they're made from the seed of a vegetable (see: sunflower, grapeseed and canola oils). But olive oil is not considered a seed oil.

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What is the healthiest oil?

If Thomason had to pick, she'd say olive oil is the best, based on the fact that it has "the most positive research and the least negative research behind it for our health." Myriad studies have found olive oil to help prevent cardiovascular diseases and decrease inflammation.

But overall, "healthy" is a loaded word in nutrition. There isn't a one-size-fits-all answer for a single best food, because everyone is different, nutrition experts stress.

"If you think of your nutrition choices as a bank account, where you make daily deposits and withdrawals, choosing nutrient dense options the majority of the time will ultimately compound on itself for your health," Thomason says. "A healthy diet is made up of our collective choices over time. Thus, one single diet choice cannot worsen your health, and similarly, one nutrition choice cannot improve your health. Using language like 'the healthiest' doesn’t help us understand the complexities of nutrition and choosing balanced choices the majority of the time."

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