With so many cooking oils to choose from, knowing how to choose the best one can be a challenge. And as you may have discovered, wading through oceans of confusing claims from wellness influencers can make it even more difficult.
Corn oil is often villainized as an inflammatory oil responsible for many of modern society’s health woes. Extra virgin olive oil fares much better, but are these claims backed up by scientific evidence? Is one better to cook with? Are oils safe to consume in general?
As a registered dietitian, I’ll answer these questions and more. I’ll compare corn oil and extra virgin olive oil and discuss their processing, nutrition profiles, health benefits, culinary uses, flavor, and more so you can feel confident when choosing between them.
Corn oil vs. extra virgin olive oil: a brief comparison
Corn oil and extra virgin olive oil (EVOO) are both plant-based oils rich in heart-healthy unsaturated fats, vitamin E, and other health-promoting compounds. Of these, corn oil is higher in phytosterols and EVOO is higher in polyphenols and carotenoids.
Corn oil is higher in polyunsaturated fats, has a higher smoke point, is more heavily processed, and has a neutral flavor. EVOO, on the other hand, is higher in monounsaturated fats, is produced without the use of heat or chemical solvents, is better at resisting oxidation, costs more, and tastes better on its own.
Processing
Between the two, corn oil is more heavily processed and refined. Corn oil is made by:
- Milling corn kerns to separate the fat-containing germ layer
- Drying the germ
- Pressing the germ into a cake with a hydraulic or screw press to extract the oil
- Treating the cake with a chemical solvent like hexane
- Evaporating the solvent, leaving the rest of the corn oil behind
The production of EVOO differs quite a bit. Olives are harvested, crushed into a paste, and cold-pressed or centrifuged to remove the oil from the solids.
Heat and chemical solvents are avoided, preserving the polyphenols and antioxidants in olive oil, as well as its unique flavor. This makes EVOO the highest quality olive oil you can buy.
RELATED: Olive Oil vs. Olive Pomace Oil
Nutrition
Let’s take a closer look at the nutritional profile of these two healthy fats.
Types of fat
Both are low in saturated fat, contain zero cholesterol, and are rich in heart-healthy unsaturated fats, although they differ in the types of unsaturated fats they contain.
Corn oil is significantly higher in polyunsaturated fats, while EVOO is highest in monounsaturated fats.
Micronutrients
Vegetable oils are known to be some of the best vegan vitamin E sources, and these two oils are no exception.
Vitamin E is typically lower in more refined oils, though corn oil and EVOO both contain at least 13% of the Daily Value. According to the USDA FoodData Central database, some brands of corn oil may contain more.
EVOO, however, is a better source of vitamin K with 7% of the Daily Value in 1 tablespoon. The amount of vitamin K in corn oil is negligible.
Other compounds
Besides fat and vitamins, these oils contain a variety of additional health-promoting compounds but differ in the types and amounts provided. I’ll discuss a few of the most significant ones here.
Carotenoids
“Carotenoids” refers to a group of pigments found in some red, orange, and yellow plant-based foods. Examples include beta-carotene in carrots, lycopene in tomatoes, and lutein and zeaxanthin in dark leafy green vegetables.
Olive oil is a much better source of carotenoids1 than corn oil thanks to the high carotenoids content of whole olives.
Phenolics
Phenolics are compounds that improve the stability of vegetable oils and protect them against oxidation.
The total amount of phenolics can vary widely based on the source and processing of each oil, but olive oil appears to be be a better source overall1.
Phytosterols
Phytosterols are beneficial compounds found in plant-based foods. They have the impressive ability to help lower cholesterol levels.
Surprisingly, corn oil appears to be much higher in phytosterols than EVOO, according to the USDA FoodData Central database. Of note, this database may underestimate total phytosterol levels2, so the true difference isn’t very clear.
Health benefits & risks
Is one of these oils healthier than the other?
Based on the available research, I’d say EVOO has the edge. EVOO has been much more widely studied for its health benefits than has corn oil, thanks in part to its inclusion in the Mediterranean Diet.
In fact, the authors of a 2023 review paper published in Nutrients3 concluded that EVOO is better than other oils for reducing blood pressure and LDL cholesterol, balancing blood sugar levels, and weight loss.
These benefits are likely due to EVOO’s high polyphenol and carotenoid content. However, corn oil can also provide health benefits, as we’ll see below.
Improved heart health
When used to replace saturated fats in the diet, both monounsaturated fats (like EVOO) and polyunsaturated fats (like corn oil) help reduce the risk of cardiovascular disease4.
Monounsaturated fats do this by helping to lower cholesterol and triglycerides and preventing the oxidation of LDL cholesterol. Oxidized LDL cholesterol damages the blood vessels and increases the risk of heart disease.
Similarly, the polyunsaturated fats in corn oil help break down cholesterol, lower triglycerides, and regulate blood pressure.
In addition, the phytosterols in corn oil are effective in lowering LDL (“bad”) cholesterol4.
Protection against oxidative stress
Humans are regularly exposed to oxidative stress from environmental pollution, smoking, an unhealthy diet, and even the normal biochemical reactions that happen in our own bodies.
Exposure to high levels of oxidative stress over time can increase the risk for many chronic diseases.
Fortunately, corn oil and EVOO can both help protect the body from oxidative stress. Both are rich in vitamin E, a powerful antioxidant.
Corn oil is also rich in phytosterols, which help boost the activity of antioxidant enzymes5 in the body.
EVOO is rich in polyphenols, which also have powerful antioxidant properties6. Its carotenoid content is also beneficial, as these pigments fight oxidative stress and reduce inflammation within the eyes, potentially reducing the risk of age-related macular degeneration7.
Increased nutrient absorption
Adding any type of fat, including corn oil and EVOO, to your meals can help increase the amount of nutrients that your body absorbs.
Carotenoids and fat-soluble vitamins A, D, E, and K are all absorbed best with fat, so it’s important to include a good source of fat at every meal, whether from oils or whole food sources like avocado, nuts, seeds, and olives.
Inflammatory potential
You may have seen claims circulating online stating that because corn oil is high in polyunsaturated fats, specifically omega-6 fats, it causes inflammation and should be avoided.
This claim comes from the idea that omega-3 fats, another type of polyunsaturated fat found in walnuts, flaxseed, and seafood, are anti-inflammatory and omega-6 fats are inherently pro-inflammatory.
While it’s true that omega-3s are anti-inflammatory, things aren’t quite as straightforward for omega-6s. Both are essential for good health and must be obtained from the diet since the body can’t produce them itself.
There is no evidence8 showing that increased consumption of omega-6 fats increases levels of inflammatory markers in the body. Some evidence even shows reduced inflammation9.
That said, some conflicting research suggests that when consumed in high amounts, omega-6 fats might reduce the anti-inflammatory benefits of omega-3 fats.
Because of this, health experts (like myself) recommend focusing on adding more omega-3s to your diet rather than obsessing over avoiding omega-6 fats.
To sum up, you don’t need to avoid corn oil over worries about inflammation, especially considering what a good source of vitamin E and phytosterols it is. When used in a nutrient-dense, balanced diet that also includes omega-3s, corn oil can be a healthful choice.
Rancidity
Two things to consider when choosing an oil are its smoke point and oxidative stability. Let’s discuss each of these in more detail.
Smoke point
An oil’s smoke point is the temperature at which the fatty acids start to break down and release toxic compounds, producing smoke.
Corn oil has a smoke point of 450℉. EVOO starts smoking at lower temperatures, between 350-410℉.
This doesn’t mean you can’t cook with EVOO, however. Most deep frying is done between 350 to 375℉, meaning it can be used even at relatively high temperatures.
The traditional understanding is that the higher the smoke point, the more resistant to heat an oil is. However, according to a 2018 study10, smoke point isn’t actually the best indicator of how well an oil resists rancidity. Oxidative stability is a much more reliable indicator of an oil’s heat tolerance.
Oxidative stability
An oil’s ability to resist oxidation is arguably much more important than its smoke point.
Oxidation can begin during storage before an oil is ever used for cooking. Over time, the individual fatty acids in oil will become damaged and start to degrade. This causes toxic compounds and off-flavors and odors to form.
Some oils are more prone to oxidation than others. Storage conditions also play a role. A few causes of oxidation include:
- Exposure to oxygen (not tightly sealed)
- Exposure to light (stored in a clear bottle)
- Exposure to warm temperatures (not stored in a cool place)
Oils are most prone to becoming oxidized when they’re:
- Low in antioxidants, polyphenols, saturated fats, or monounsaturated fats
- High in polyunsaturated fats
EVOO has excellent oxidative stability thanks to its high content of antioxidants, polyphenols, and monounsaturated fats. This helps it stay fresher longer.
Corn oil does contain antioxidant vitamin E, but isn’t as high in polyphenols as EVOO. It’s also made up primarily of polyunsaturated fats, which lower its ability to resist oxidation.
That said, it has been shown to have better oxidative stability11 than rice bran, grapeseed, and rapeseed oils.
Culinary uses
Because of its neutral flavor, corn oil is primarily used in processed foods and high-heat applications like deep-frying. It’s also commonly used as a cooking oil in home kitchens and can also be used in baked goods when a neutral flavor is required.
EVOO has a much more pleasant flavor and color, making it an excellent choice for simple vinaigrettes, sautéing, dipping bread, marinades, brushing on toasted bread, and drizzling over main dishes.
Price
When looking at prices across mainstream grocery retailers, EVOO can cost anywhere from three to five times as much as corn oil.
As you might expect, EVOO prices vary based on the brand name and organic certifications. Organic corn oil is hard to come by, which keeps the average prices lower.
Which should you choose?
The choice is really up to you. If you’re looking for the most versatile, best-tasting oil with the greatest oxidative stability and health benefits, EVOO is the winner.
However, corn oil isn’t the dietary villain many wellness influencers make it out to be. It’s a healthier choice than saturated fats like butter, is a budget-friendly source of antioxidant vitamin E, and offers a surprisingly impressive amount of phytosterols.
RELATED: Canola Oil vs Sunflower Oil
The scientific information in this article was accurate at the time of publishing but may change over time as new research becomes available.
References
- Tian M, Bai Y, Tian H, Zhao X. The Chemical Composition and Health-Promoting Benefits of Vegetable Oils-A Review. Molecules. 2023;28(17):6393. Published 2023 Sep 1. doi:10.3390/molecules28176393
- Higdon, Jane. Phytosterols. Linus Pauling Institute. Oregon State University website. Published 2005, reviewed March 2017. Accessed 3/4/25.
- Flynn MM, Tierney A, Itsiopoulos C. Is Extra Virgin Olive Oil the Critical Ingredient Driving the Health Benefits of a Mediterranean Diet? A Narrative Review. Nutrients. 2023;15(13):2916. Published 2023 Jun 27. doi:10.3390/nu15132916
- Tian M, Bai Y, Tian H, Zhao X. The Chemical Composition and Health-Promoting Benefits of Vegetable Oils-A Review. Molecules. 2023;28(17):6393. Published 2023 Sep 1. doi:10.3390/molecules28176393
- Bakrim S, El Omari N, Khan EJ, et al. Phytosterols activating nuclear receptors are involving in steroid hormone-dependent cancers: Myth or fact?. Biomed Pharmacother. 2023;169:115783. doi:10.1016/j.biopha.2023.115783
- Rudrapal M, Khairnar SJ, Khan J, et al. Dietary Polyphenols and Their Role in Oxidative Stress-Induced Human Diseases: Insights Into Protective Effects, Antioxidant Potentials and Mechanism(s) of Action. Front Pharmacol. 2022;13:806470. Published 2022 Feb 14. doi:10.3389/fphar.2022.806470
- Pawlowska E, Szczepanska J, Koskela A, Kaarniranta K, Blasiak J. Dietary Polyphenols in Age-Related Macular Degeneration: Protection against Oxidative Stress and Beyond. Oxid Med Cell Longev. 2019;2019:9682318. Published 2019 Mar 24. doi:10.1155/2019/9682318
- Fritsche KL. Linoleic acid, vegetable oils & inflammation. Mo Med. 2014;111(1):41-43.
- Innes JK, Calder PC. Omega-6 fatty acids and inflammation. Prostaglandins Leukot Essent Fatty Acids. 2018;132:41-48. doi:10.1016/j.plefa.2018.03.004
- Guillaume C., et al. “Evaluation of Chemical and Physical Changes in Different Commercial Oils during Heating”. Acta Scientific Nutritional Health 2.6 (2018): 02-11
- Maszewska M, Florowska A, Dłużewska E, Wroniak M, Marciniak-Lukasiak K, Żbikowska A. Oxidative Stability of Selected Edible Oils. Molecules. 2018;23(7):1746. Published 2018 Jul 17. doi:10.3390/molecules23071746
