Healthy ideas for your inbox
The “Hateful Eight” isn’t the latest supervillain movie; it’s what some people are calling a group of cooking oils made from seeds of different plants that have been the subject of recent scrutiny.
The eight vegetable oils in question are: cottonseed, soy, sunflower, safflower, corn, rice bran, grapeseed and canola. Critics say that the high amounts of omega-6 fatty acids found in seed oils can cause inflammation, leading to (or worsening) inflammatory conditions like diabetes, heart disease or other chronic illnesses.
But if you have any of these seed oils in your kitchen, don’t send them to an early trash-can grave just yet. The oils aren’t the villains in this story — they might actually give your body the extra nutrition it needs.
Seed oils aren’t bad for you
Seed oils are safe and even healthy to use, says Judy Simon, MS, RD, a registered dietitian nutritionist at the Nutrition Clinic at UW Medical Center – Roosevelt.
They are made of polyunsaturated fats and monounsaturated fats, which can have heart-healthy benefits.
Monounsaturated fats from plants can lower bad cholesterol, raise levels of good cholesterol and improve blood sugar, and polyunsaturated fats are high in fatty acids like omega-6 and omega-3, which are necessary for your diet.
Some cooking oils (including a few of the Hateful Eight) like flaxseed, hemp, pumpkin seed, sesame, sunflower and safflower are especially good for you because they may have more monounsaturated fats than others, says Simon.
They also have lower quantities of saturated fats, an unhealthy type of fat found in foods like butter, fatty cuts of meat, and some cheeses.
Does omega-6 cause inflammation?
The claims about polyunsaturated fats causing inflammation are a bit more complicated. Polyunsaturated fats contain omega fatty acids, which play an important role in your diet. Our bodies can’t make them, which is why it’s important to eat foods (or take supplements) that have them.
You’ve probably heard the most about omega-3s: They are known to help fight inflammation, improve heart health, support mental health and more. You can typically get your recommended daily dose of omega-3 (1.6 grams for men and 1.1 grams for women) by eating fish, nuts, seeds and, yes, some seed oils, such as canola or soybean oil.
Omega-6 fatty acids provide our bodies with energy and play a role in maintaining health. They support cell structure, contribute to brain development and even help regulate hormones and metabolism.
Why the inflammation claims, then? Well, linoleic acid, which is the primary omega-6 in seed oils, converts to something called arachidonic acid. Arachidonic acid plays a role in your body’s inflammatory response.
But here’s the thing: Inflammation doesn’t always equal bad. Your body uses it to protect itself from infections and injuries. Too much of it isn’t great, sure, but that typically won’t happen from having seed oils in your diet.
“The inflammation claims made by the critics that seed oils can cause heart disease, diabetes or other chronic conditions aren’t supported by research,” says Simon. “Studies have shown that dietary intake of linoleic acid doesn’t increase inflammatory markers in the blood. Linoleic acid may actually help lower risk for cardiovascular disease, type 2 diabetes, cancer and earlier death.”
Inflammation, however, isn’t the only problem seed oil detractors have with the Hateful Eight.
Hexane risks in seed oils
Another concern is the method companies use to extract seed oils. This industrial process uses hexane, a petroleum-derived solvent, to extract the oil from the seeds. Some claim this leaves toxins from the hexane in the seed oil, which you then ingest when you cook with it.
But while high amounts of hexane can be dangerous as a gas, its liquid form is used to extract seed oils. It then evaporates during the process, leaving an extremely low or undetectable amount of hexane in the final product.
“If you’re still concerned about this exposure, you can buy cold-pressed seed oils,” says Simon. “But you have much higher exposure to hexane at your gas pump when filling your car.”
Context matters when thinking about seed oils
Of course, it’s good to try to avoid anything in excess. If you’re only getting omega-6s in your diet from seed oils in deep-fried or fast foods (and you’re eating a lot of it), your body won’t love that or its excess calories. Not to mention, many of those foods are ultra-processed, which can increase your risk for lots of health conditions.
“Many snack foods, like chips and crackers, use seed oils, and folks will claim they cause obesity or diabetes based on the foods they’re found in,” says Simon.
But a processed food isn’t inherently unhealthy. Foods like flavored yogurt or store-bought, whole wheat bread are also ultra-processed, but still have nutritional value. Eating these kinds of foods is OK if you’re also eating a good amount of healthy, minimally processed foods, too.
So, yes, it is safe and healthy to use seed oils
Next time you’re in the kitchen, don’t feel the need to reconsider cooking your stir-fry in your favorite seed oil. But if you ultimately want other options for healthy cooking oils, you can try olive, avocado and peanut oils.
In the end, remember that seed oils themselves aren’t the villains here to ruin the day — or your body. When balanced with a healthy diet, you’ll get the tasty benefits of your favorite cooking oils (and the added health benefits, too).
