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What oil should you stay away from?

Cooking oils are an essential part of any kitchen. However, not all cooking oils are created equal. Some oils are better for you than others due to their fat composition, while other oils can even be downright harmful if consumed in large quantities over long periods of time. So which oils should you limit or avoid altogether? Here’s a breakdown of the worst cooking oils for your health.

Vegetable Oil

Vegetable oil is one of the most common cooking oils used today. It is made by blending different types of plant oils like soybean, corn, sunflower, canola, etc. While vegetable oil is high in polyunsaturated fats, which are considered healthier than saturated fats, the manufacturing process used to make vegetable oil creates an imbalance between omega-3 and omega-6 fatty acids. This imbalance can lead to inflammation in the body when consumed regularly. Opt for healthier monounsaturated fat oils like olive oil or avocado oil instead.

Canola Oil

While canola oil contains monounsaturated fats like olive oil, the vast majority of canola grown today is from genetically modified crops that are doused with pesticides. There are also concerns around the processing methods used to extract canola oil, which often involves high heat, chemical solvents, and bleaching agents. This processing depletes the oil of any nutrients while introducing free radicals and trans fats. Instead, choose organic expeller-pressed canola oil or avoid canola oil altogether.

Corn Oil

Corn oil is high in omega-6 fatty acids, which in excess can lead to inflammation. Most corn oil today also comes from genetically modified corn that has been sprayed with pesticides and herbicides. Look for organic, non-GMO varieties of corn oil if you want to use it, but otherwise, oils like olive oil and avocado oil are much healthier alternatives.

Cottonseed Oil

Cottonseed oil contains high levels of inflammatory omega-6 fatty acids and is often derived from conventionally-grown cotton that has been heavily sprayed with pesticides. There are also sustainability concerns around growing cotton. With so many healthier plant-based oils to cook with, cottonseed oil is best avoided.

Palm Oil

While palm oil gets a bad rap for being high in saturated fat, organic and sustainably-sourced palm oil that hasn’t been chemically processed is actually quite neutral health-wise. However, the vast majority of palm oil on the market today is conventionally grown and processed using high heat and hexane solvents. This processing generates more saturated fats and trans fats, while depleting any beneficial nutrients. Mass palm oil production also contributes to rapid deforestation, habitat destruction, and climate change. For these ethical and sustainability reasons, conventionally-produced palm oil is best avoided.

Partially Hydrogenated Oil

Partially hydrogenated oils contain trans fats, which are the unhealthiest type of fats you can consume. Trans fats raise LDL (bad) cholesterol levels while lowering HDL (good) cholesterol. Even small amounts of trans fats can negatively impact heart health, so it’s best to completely avoid partially hydrogenated oils whenever possible. Always check ingredient labels and avoid products with any partially hydrogenated oils listed.

Soybean Oil

Like vegetable oil, soybean oil typically contains an imbalance of omega-3 and omega-6 fatty acids, which can promote inflammation when eaten regularly. The majority of soybean oil is also made from GMO soybeans that have been doused with chemical pesticides and herbicides. For the healthiest choice, use organic soybean oil in moderation or avoid it altogether in favor of oils higher in monounsaturated fats like olive oil.

Rice Bran Oil

Rice bran oil is high in omega-6 fatty acids compared to other oils. In excess, these omega-6s can contribute to inflammation. Rice bran oil also has a high smoke point, making it ideal for frying and stir-frying at extremely high temperatures. However, oils heated to high temperatures can denature and produce harmful compounds and free radicals. For the healthiest choice, use rice bran oil sparingly for light sautéing and baking.

Coconut Oil

Coconut oil contains a unique blend of fatty acids including lauric acid, which offers some health benefits. However, more than 90% of the fats in coconut oil are saturated. Too much saturated fat from any source may negatively impact heart health by raising LDL (bad) cholesterol over time. While moderate amounts of coconut oil are probably harmless for most people, it’s wise to limit your coconut oil intake and get most of your fats from healthier monounsaturated and omega-3 polyunsaturated sources instead.


When it comes to cooking oil, your best bet is to choose plant-based, unrefined oils that are high in monounsaturated fats like olive oil and avocado oil. Oils rich in omega-3s like flaxseed oil and walnut oil are also excellent choices. Limit your use of oils high in omega-6s and saturated fats like vegetable, soybean, corn, cottonseed, rice bran and coconut oils. And always avoid oils with trans fats like partially hydrogenated oils that are linked to numerous health problems. By making informed choices about your cooking oils, you can avoid the unhealthiest options and enjoy the flavors, textures, and benefits that good fats add to your meals.