Which oil is best for frying? Study busts myth

Posted on Tue, 15 May 18

Which oil is safest to cook with is a common question in nutrition. The typical answer, however, may have been based on a scientific myth.  

Advice regarding which oil is best too cook with is often based on “smoke point,” the temperature at which an oil visibly starts to burn and smoke. The theory goes that the lower the smoke point, the more susceptible an oil is to high heat and the less safe it is for you to cook with. 

A new study busts this myth by testing the generation of oil degradation by-products including secondary products of oxidation and polar compounds harmful to health [1].

The study tested: 

• Extra Virgin Olive Oil 
• Virgin Olive Oil  
• Olive Oil 
• Canola Oil
• Rice Bran Oil
• Grapeseed Oil
• Coconut Oil
• Peanut Oil
• Sunflower Oil
• Avocado Oil

The oils were heated up to 240 degrees Celsius and exposed to 180 degrees for 6 hours, with samples assessed at various times, testing smoke point and chemical characteristics associated with stability and safety when heating.

Extra virgin olive oil (EVOO) had the lowest levels of polar compounds and oxidative by-products, with the study investigators proposing that EVOO’s unique fatty acid profile and natural antioxidant content allowed the oil to remain stable when heated. 

Importantly, smoke point did not predict oil performance. 

The observation that EVOO is a safer oil to fry with is consistent with observations from multiple studies that the use of EVOO in cooking, including frying, is associated with a lower risk for chronic disease [2]. 

Reference: 

1. 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.
2. Sayon-Orea C, Carlos S, Martínez-Gonzalez MA. Does cooking with vegetable oils increase the risk of chronic diseases?: a systematic review. Br J Nutr. 2015 Apr;113 Suppl 2:S36-48.