The Healthiest Oils for Brain Health

by Lacy Kuester MS, MPP, RDN and Amylee Amos PhD, RDN, IFMCPNutrition
Bottle of olive oil

Grocery stores normally sell a plethora of oil options: canola oil, vegetable oil, soybean oil, avocado oil, olive oil. Even within the olive oil selection itself there are a variety of options! It can be confusing, to say the least, to know which oil is best when making a decision based on health. Recipes often call for a specific oil in their ingredients, but is the oil recommended a healthy option? Not always.

Shopping for Oils

Many of the labels in the oil section are misleading. For example, an oil that claims on its label to be good for heart health may be highly inflammatory and contribute to cancer and cognitive decline. While that can seem ridiculous, the regulations of the food industry allow for such egregious misrepresentations. For this reason, it’s important that when you shop for oils, you know which oils will support your health and which will contribute to disease.

To make matters even more difficult, the healthiest oil for use without heating is not necessarily the healthiest oil for cooking. This is because oils possess different smoke points. The smoke point is the temperature at which an oil begins to degrade, changing its chemical composition as well as its taste. If an oil is heated above its smoke point, it can form harmful compounds in your food as well as in the air in your kitchen (4, 5). Different oils have different smoke points, making some safer for high-temperature cooking than others. Many inexpensive oils have very high smoke points and are often used for high heat cooking, such as canola oil, soybean oil, vegetable oil, and grapeseed oil. However, these oils are highly refined, are usually chemically extracted, and can contribute to inflammation in the body. Additionally, they give off a higher level of carcinogens, even when heated below their smoke point (3, 5, 7).

In this article we outline which oils are best for use without or on low heat and which are best for cooking, as well as the worst oil choices to use.

Best Oil for Low or No Heat: Extra Virgin Olive Oil

Olive oil is the clear winner when choosing an oil to use without or on low heat. Olive oil is packed with good fats and phytonutrients that support your cognitive function and overall health, making it a staple in the kitchen of anyone looking to improve brain health. All quality cold-pressed olive oils -- whether they’re extra-virgin (EVOO), virgin (VOO), or refined (OO) -- have similar beneficial fat content. What changes substantially in these oils as they become more refined is their phytonutrient content. Cold-pressed, EVOO has the most phytonutrients because it’s the least processed. Think of it as being the closest thing to the olives from which it was made. The very best extra virgin olive oil has a high polyphenol content, has a known harvest date, and is stored in a dark bottle. This type of extra virgin olive oil will have a very strong, often even peppery flavor and will appear green in color.

VOO has fewer phytonutrients than EVOO, and even fewer remain in refined OO (1, 2, 4). We definitely want to maximize our intake of cold-pressed EVOO to get the benefit of phytonutrients to support our brain health.

EVOO has a relatively low smoke point of 383℉, making it unideal for recipes that call for higher heat. Because EVOO doesn’t have a very high smoke point, it’s best used for dressing, drizzling, and dipping. The beneficial polyphenols in good quality EVOO are fragile and can be degraded at higher temperatures, so reserve EVOO for use without heating or over very low heat.

Cooking with Oils

The smoke point is not the only thing to consider when choosing an oil with which to cook. You should also know that heat, even when below the smoke point, destroys phytonutrients and antioxidants (that’s why it’s important to choose an EVOO that’s cold-pressed. It preserves the phytonutrients). When cooking with EVOO, the smoke point may be 383℉, but studies have shown that the phytonutrients in EVOO are destroyed at much lower temperatures. By ~350℉, all phytonutrients are cooked off, leaving you with the same healthy fats you would get in a high-quality OO (1, 2, 6). If you’re cooking below 350℉ or applying no heat to your food (i.e. making salad dressings, drizzling your food with olive oil, etc), then EVOO is the way to go. We want you to get those phytonutrients whenever possible. However, if you’re applying a higher heat to your food, choose an oil that’s better suited for cooking.

Best Oil for Higher Heat Cooking: Avocado Oil

Avocado oil is well suited for higher heat cooking, with a smoke point of 520℉. Avocado is relatively flavorless, so it works well for all different types of cuisines, as well as baked goods. Like olive oil, look for avocado oil that is cold-pressed and stored in a dark colored, glass container.

What about other oils?

While extra virgin olive oil is the best oil for low or no heat, and avocado oil is the best oil for cooking, some of the other oils available can also have a place in a brain healthy diet. Some oils like macadamia nut oil, sesame oil, and walnut oil are healthy and delicious oils for finishing. In other words, drizzle these oils on foods to add a punch of flavor and antioxidants when indicated for a particular dish or flavor profile.

The oils that should always be avoided include canola oil, corn oil, soybean oil, sunflower oil, safflower oil, and vegetable shortening. These oils are heavily processed which removes the beneficial plant compounds and are often chemically extracted, a process that imparts chemicals and harmful compounds into the oil. Additionally, the fat profile of these oils is more inflammatory than the healthier oils listed above.

Key Takeaways

Research shows that high-quality extra virgin olive oil is beneficial for your cognitive health and overall health. The less processed the oil is, the more nutrients it contains. Cold-pressed EVOO with a known harvest date, that has been stored in a dark colored glass bottle is the most phytonutrient-packed option, but it’s also the most delicate. Applying heat destroys EVOO’s nutrients, so it’s best used when applied raw to food. Use avocado oil, which has healthy fats and a much higher smoke point when cooking foods. For a recommendation of a great extra virgin olive oil with some of the highest amounts of brain healthy polyphenols, contact your Amos Institute dietitian today!

References:

  1. Boskou, D. (Ed.). (2015).Olive oil: chemistry and technology.Retrieved from https://ebookcentral.proquest.com
  2. Brenes, M., García, A., Dobarganes, M., Velasco, J., & Romero, C. (2002). Influence of thermal treatments simulating cooking processes on the polyphenol content in virgin olive oil.Journal of Agricultural and Food Chemistry, 50(21), 5962–5967.https://doi.org/10.1021/jf020506w
  3. U.S. Department of Agriculture. (2013).Deep fat frying and food safety. Accessed Jan 13 2020 from https://www.fsis.usda.gov
  4. Öğütcü, M., Aydeniz, B., Büyükcan, M., & Yılmaz, E. (2012). Determining Frying Oil Degradation by Near Infrared Spectroscopy Using Chemometric Techniques.Journal of the American Oil Chemists’ Society, 89(10), 1823–1830. https://doi.org/10.1007/ s11746-012-2087-x
  5. Katragadda, H., Fullana, A., Sidhu, S., & Carbonell-Barrachina, Á. (2010). Emissions of volatile aldehydes from heated cooking oils.Food Chemistry, 120(1), 59–65. https://doi.org/10.1016/j.foodchem.2009.09.070
  6. Santos, C., Cruz, R., Cunha, S., & Casal, S. (2013). Effect of cooking on olive oil quality attributes.Food Research International, 54(2), 2016–2024.