Seed oils — sunflower oil, canola oil, and so on — are the backbone of cooking due to their high smoke point and neutral taste. However, recent research suggests that they may be less healthy than other forms of oil. But the discussion is still ongoing. Are seed oils bad for you? If so, how bad are they? As a nutritionist, these have been common concerns my clients have shared with me, and they are curious about what healthy swaps they can make.
In this article, we’ll break down the science and help you figure out whether seed oils are bad for you. We’ll also look at some great healthy oils to use in your cooking instead. Let’s get started!
What are seed oils?
Seed oils are a type of vegetable oil. Vegetable oil is anything that comes from plants instead of animals, as opposed to oils like butter, bacon, grease, and lard. Seed oils include any type of oil that comes from any type of seed, including canola, corn, grapeseed, soybean, peanut, and sunflower.
Are seed oils bad for you?
People who believe seed oils have negative effects point to the chemical refining process used to create these oils, and the high concentrations of omega-6 fats. Omega-6 fats are actually healthy in moderate quantities, but too much can create inflammation. Mostly this is only a problem if you eat a lot of processed food, which often has high amounts of oil, including seed oils.
There are also sources, including the American Heart Association, that suggest seed oils aren’t that bad, especially in home cooking. Omega-6 fats can cause some inflammation, but not usually enough to affect your health, they say, and seed oils are better and healthier than animal fats like butter or bacon grease. Much of the dangers attributed to seed oils are based on the fact that they’re frequently found in unhealthy, hyper-processed foods, but processed foods contain many other compounds that are much worse than seed oils.
What seed oils should you avoid?
Any oil that comes from seeds is a seed oil. If you’ve decided to avoid seed oils, these are the most common types:
- Canola oil
- Soybean oil
- Sunflower oil
- Corn oil
- Peanut oil
- Grapeseed oil
- Safflower oil
None of these are particularly worse or better than others. If you find a product that just says “vegetable oil,” that’s usually a mixture of corn, canola, and soybean oil in varying quantities. This is also common to see on ingredient labels, and it might not say exactly what all of its components are.
Possible risks of overconsuming seed oils
Inflammation
The omega-6 fats found in seed oils can cause inflammation. According to the Cleveland Clinic, “American diets typically already include too many omega-6s. This throws off your body’s ratio of omega-6 fatty acids to omega-3 fatty acids, leading to inflammation in the body.” Although the American Heart Association says that the inflammation caused by omega-6s is usually fairly minor if you’re struggling to reduce inflammation, cutting out or reducing seed oils might help.
Weight gain
Seed oils contribute less to weight gain than animal fats, but of course, they’re still oil. If you’re looking for healthy fats, you’d better look somewhere else. Almost all nutritional content found in seeds and nuts has been stripped out by the chemical process of refining the oil. Again, in moderation, this is not very serious. But if you’re eating, for example, large quantities of fried fast food, you could be getting a lot more oil in your diet than you realize.
Allergies
Several common seed oils can be a risk for people who are allergic to their ingredients, most notably peanut oil and soybean oil. And “vegetable oil” is usually a blend of a variety of seed oils, often including soy, which makes it a sneaky potential allergen hiding in plain sight on an ingredients list. In contrast, very few people are allergic to olives and avocados.
Healthy alternatives to consider
- Olive oil: Olive oil is famously “the healthy oil,” but it’s for good reason. Olive oil contains healthy fats, polyphenols, and antioxidants. It’s usually more flavorful than the more neutral seed oils and may have a lower smoke point, but it’s unbeatable for nutrition.
- Coconut oil: Coconut oil is a saturated fat, which is different from most vegetable oils. It can bring an interesting flavor to a dish, and it has several health benefits, from immune support to brain health.
- Avocado oil: Avocados are one of the best healthy fats, and avocado oil is also excellent for cooking. It has little flavor and a very high smoke point, so you can use it for everything from tossing a salad to searing a steak.
- Expeller-pressed oils: One of the major problems with seed oils is that much of their nutritional value has been stripped through a chemical refining process. However, organic, expeller-pressed oils haven’t been through that process, and they’re still full of all the advantages of the original seeds!
Frequently asked questions
Is seed oil worse than olive oil?
Nutritionally, yes. Olive oil is hard to beat, and seed oils have almost no nutritional content after they’ve been processed. For cooking, on the other hand, seed oil is often better than olive oil; it has a higher smoke point for high-temperature uses like searing and less flavor.
What is the healthiest oil to use?
There are several good oil choices. Olive oil is at the top of most lists, but avocado oil is almost as good, and it’s more versatile in the kitchen. Coconut oil is another notable option.
Are seed oils worse than butter?
Seed oils are much healthier than butter. Butter contains saturated fats, as opposed to the unsaturated fats of almost any type of vegetable oil, and is much worse for your circulatory system. (However, it can still be enjoyed in moderation!)
