Food Facts Friday: Cooking Oils

Oils are used in several ways, including for cooking, baking, frying and as a way to add flavor to a salad. With so many uses, it’s no surprise there is a variety of oil types. It can seem like there’s a new type of oil every time you go grocery shopping. How do you know which oil is best? Read on to learn more about the different kinds of cooking oils.

Cooking Oil Facts

Oils are a source of fat. Monounsaturated and polyunsaturated fats have been associated with reduced risk of heart disease compared to saturated fats.¹ The American Heart Association recommends that most of your fat intake be monounsaturated or polyunsaturated fats.¹ People with kidney disease are at a higher risk of developing heart disease, so it’s even more important to eat the fats that help lower your risk.² 

Besides their fat content, oils vary in other characteristics that affect how they should be used. Oils have a smoke point, or burning point, which is the temperature the oil starts to smoke up and integrity changes.³ When an oil starts to smoke, it can change the flavor and produce free radicals that can be harmful. When cooking, it is best to heat the pan first, add oil and then add the ingredients to prevent the oil from getting too hot quickly.

It is ideal to store oils in a cool, dark place.³ Storing oils over the stove can cause them to become rancid. The quality of oil is best when used within one year of purchase.

Four Popular Cooking Oils

Olive Oil

Olive oil, a staple in the Mediterranean diet, comes from pressed whole olives and is high in monounsaturated fats.⁴ The National Kidney Foundation shares that olive oil is a healthy choice for people with kidney disease as 1 tablespoon contains less than 1 mg sodium, less than 1 mg potassium, and 0 mg phosphorus. Extra virgin olive oil has a moderate smoke point of 325 to 375° F, making it appropriate for sautéing over medium heat or roasting below the smoke point. It also makes a great salad dressing or dip for bread.³

Canola Oil

Canola oil comes from rapeseeds and is high in monounsaturated and polyunsaturated fats.⁴ It does not contains phosphorus or potassium. Canola oil has a high smoke point of 400° F and is used for cooking, baking and sautéing at a higher temperature.

Avocado Oil

Avocado oil comes from the flesh of pressed avocados and contains the highest levels of monounsaturated fats of all oils. Although avocados are high in potassium, avocado oil does not contain potassium or phosphorus.^5,6 Smoke point is 375° F for virgin oil and 520° F for refined. This oil is mild in flavor, making it a good oil to use in baked goods. It is also good for frying and roasting.

Coconut Oil

Coconut oil comes from the meat of the coconut.⁴ It is high in saturated fat, which is why it is solid rather than liquid at room temperature. It has gained popularity for providing health benefits, but the research on coconut oil is inconsistent.³ It does not contain phosphorus or potassium.⁷ The smoke point is lower compared to the other oils at 350° F, making it best used in baking and sautéing.³ Coconut oil is higher in fat solids compared to butter, so when substituting coconut oil for butter in baked goods you should use 25% less coconut oil.

Summary  

The American Heart Association and the National Kidney Foundation recommend that most of your fat intake be monounsaturated and polyunsaturated fats. Olive, avocado and canola oils are all good sources of unsaturated fats, making them good options for cooking oils. Coconut oil is high in saturated fat, but can still be used in moderation.

References:

1. Healthy Cooking Oils. American Heart Association. Last reviewed April 24, 2018. Accessed December 3, 2020. https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/fats/monounsaturated-fats
2. Heart Disease and Kidney Disease. National Institute of Diabetes and Digestive and Kidney Disease. Updated June 2016. Accessed December 8, 2020. https://www.niddk.nih.gov/health-information/kidney-disease/heart-disease?dkrd=/health-information/kidney-disease/chronic-kidney-disease-ckd/heart-disease#learn
3. The Healthiest Cooking Oils, According to a Registered Dietitian. Stefani Sassos. Good Housekeeping. Published April 27, 2020. Accessed December 8, 2020.  https://www.goodhousekeeping.com/health/diet-nutrition/g32108013/healthiest-cooking-oils/#:~:text=%20The%20Healthiest%20Cooking%20Oils%2C%20According%20to%20a,great%20vegan%20source%20of%20healthy%20omega-3…%20More%20
4. Cooking Oils: Test Your Oil IQ. National Kidney Foundation. Accessed on December 2, 2020. https://www.kidney.org/news/keephealthy/newsletter/KH_Test-Your-Oil-IQ#:~:text=%20Cooking%20Oils%3A%20Test%20Your%20Oil%20IQ%20,slightly%20%22nutty%22%20flavor.%20It%20is%20very…%20More%20
5. 6 Cooking Oils Explained: What to Use, What to Avoid. WebMD. Last reviewed on June 15, 2020. Accessed on December 3, 2020. https://www.webmd.com/hypertension-high-blood-pressure/fats-and-oils-explained#:~:text=6%20Cooking%20Oils%20Explained%3A%20What%20to%20Use%2C%20What,2.%20Avocado%20oil.%203%203.%20Canola%20oil.%20
6. Avocado Oil: Is It Good for You? WebMD. Last reviewed on September 30, 2020. Accessed on December 7, 2020. https://www.webmd.com/diet/avocado-oil-good-for-you#1
7. USDA Food Data Central: Coconut Oil. https://fdc.nal.usda.gov/fdc-app.html#/food-details/1103857/nutrients

Additional Kidney Diet Resources

Visit DaVita.com and explore these diet and nutrition resources:

• DaVita Food Analyzer
• DaVita Dining Out Guides
• Today’s Kidney Diet Cookbooks
• DaVita Kidney-Friendly Recipes
• Diet and Nutrition Articles                                                       
• Diet and Nutrition Videos
• Kidney Smart® Virtual Classes

This article is for informational purposes only and is not a substitute for medical advice or treatment. Consult your physician and dietitian regarding your specific diagnosis, treatment, diet and health questions.