Before answering this recurring question, it is important to know what is the difference between the two oils. The food technologist Miguel Angel Lurueña accounts for Damn science that the differences lie above all in its composition of fatty acids: in olive, the monounsaturated while in the sunflower the polyunsaturated.
When is it advisable to cook with olive or sunflower oil?
Both are considered healthy, but “when we subject them to high temperatures as we do when we cook, the heat oxidizes its molecules and, as a consequence, undesirable compounds for health are formed “. “It is easier for this to happen with polyunsaturated (present in sunflower oil) because they are more unstable”, says the expert.
Therefore, Lurueña considers healthier cooking with olive oil than with sunflower oil. Although we opt for high oleic sunflower oil (healthier than normal sunflower oil), olive oil is still preferable because it has compounds called polyphenols that help minimize oxidation.
Different studies have pointed out the health benefits of olive oil. For example, research published in the journal Diabetes, obesity and metabolism indicates that the consumption of olive oil enriched in oleanolic acid can reduce the risk of developing diabetes in prediabetic people.
According to other research published in the European Journal of Nutrition, the consumption of virgin olive oil prevents inflammation in blood vessels and can reduce the risk of developing atherosclerosis (when fat, cholesterol and other substances accumulate on the walls of the arteries).
Dietitian-nutritionist Daniel Ursúa agrees and points to Damn science which, due to its molecular structure, olive oil is more resistant to heat and it takes longer to generate compounds that are potentially harmful to our body than the sunflower.
Of the same opinion is the dietitian-nutritionist Elisa Escorihuela, who confirms Damn science that cooking with olive oil is always healthier. “When it comes to cooking, olive oil tends to be used more raw and sunflower oil for frying, but this is due more to an economic question than health”, It indicates.
Lurueña recommends do not reuse oils that have been subjected to high temperatures or that have reached the point of smoke (when smoke comes out of the pan). When this does not happen, if it is reused, the expert advises not to do it more than three times and filter it previously.
For her part, Beatriz Robles, dietician-nutritionist, considers better do not reuse the same oil. “In each heating cycle in the presence of water (typical of frying, where food supplies water), reactions take place that releases fatty acids and this reduces resistance to heat.” This, according to account Damn science translates into low oil quality, but also in what toxic compounds appear.