1674155730 Two studies suggest that olive pomace oil lowers cholesterol insulin

Two studies suggest that olive pomace oil lowers cholesterol, insulin levels and waist circumference

Raquel Mateos Briz, senior scientist at the Institute of Food Science and Technology and Nutrition (ICTAN-CSIC) and co-author of the research, in the center's laboratories.Raquel Mateos Briz, senior scientist at the Institute of Food Science and Technology and Nutrition (ICTAN-CSIC) and co-author of the research, in the center’s laboratories.

While extra virgin olive oil has been widely studied, its brother, derived from the integral use of the olive and known as olive pomace oil, has not previously had relevant and verified human research that would allow its effects on consumer health to be determined. The Institute of Food and Nutrition Science and Technology (ICTAN) of the Higher Council for Scientific Research (CSIC) has begun to fill this gap with two human studies. These point to the benefits of its intake in lowering cholesterol, visceral fat, waist circumference and insulin levels, aspects that are directly related to cardiovascular health and related conditions such as diabetes and obesity. Studies have compared the effect of consuming olive pomace oil with high oleic sunflower oil, which is widely used in restaurants, and with the second most consumed oil in Spain, sunflower oil. The results showed that the product from the olive grove offers benefits that products from the seeds do not.

Although this depends on many factors, on average 20% of the olives are used to obtain olive oil in its three categories (extra virgin olive, virgin olive and olive). The remaining 80% is alpeorujo, or wet fat pomace, which is made up of water, skin, stone, and the oil left after the olive is first ground. Olive pomace oil is the result of extracting this remaining oil, refining it and blending it with virgin oil.

“In short, olive pomace oil comes from olives and therefore it is normal for the composition to be similar. The quality of the fat is identical, monounsaturated. Some of the minor components are different because the olive pomace oil has been in contact with the skin, bone and remaining pulp,” explains Raquel Mateos Briz, senior scientist at ICTAN, co-author of the studies and member of the research group Metabolism and Bioactivity of Phytochemicals.

Despite the reasons for this positive suspicion, the studies on this product, of which Spain is the world’s leading producer with 120,000 tons, 85% of which is exported, had not been extrapolated to humans and, after animal testing, had focused more on its nutritional potential , their chemical and physical properties as well as their behavior during frying. The study presented this Thursday takes this fundamental step.

“The characteristic of these studies is that they are chronic, that is, for a while [cuatro semanas] Olive pomace oil was the only source of fat consumed by the volunteers. Some studies have measured what happens in the blood within hours of an acute ingestion. But it was a special moment. This is the first time a chronic study has been conducted to see the changes in the markers under study, which in our particular case were associated with cardiovascular health, obesity and diabetes,” adds Mateos Briz.

More information

The first of the studies, published in the European Journal of Nutrition, concludes that olive pomace oil may improve blood lipid profile. This work evaluates the effect of dietary consumption of olive pomace oil on blood lipids and other secondary risk factors for cardiovascular disease, such as blood pressure, inflammation, and the function of the endothelium (the layer that separates blood tissue).

The results show a significant reduction in what is known as “bad” cholesterol (low-intensity lipoproteins, LDL) and apoliprotein B (proteins that bind to and transport lipids in the blood). This decrease was seen in both healthy volunteers and those at risk for abnormalities related to high cholesterol. However, the same effect was not registered after consumption of high oleic sunflower oil. The other evaluated secondary biomarkers were not affected in any of the cases.

In the second of the studies comparing olive pomace oil to sunflower oil, collected from Nutrients and conducted on 31 volunteers with normal cholesterol levels and 37 with hypercholesterolemia, consumption of either product had “statistically significant effects on markers associated with lipid profile.” However, there was a decrease in visceral fat and, in the participants with high cholesterol, an increase in leptin, a hormone that promotes reduced energy intake through satiety signals in the brain. While acknowledging the need for further studies, the authors conclude that “reducing visceral fat after prolonged olive pomace oil intake may contribute to improvement in cardiometabolic status, with a potentially beneficial effect on vascular tone.”

The discrepancy between one study and another [en relación con el perfil lipídico] This is because these are human studies. Experimental animals have a very similar genetic profile and are easier to control and systematize. This is not the case in humans and we do not have the same lifestyle, physical activity or dietary habits. All of these factors affect how each person responds to ingestion of the oils studied,” explains Laura Bravo Clemente, CSIC research professor at ICTAN and co-author of the paper.

waist size

The third of the studies, derived from the integration of the results of the two clinical studies described in the previous articles, was published in Foods and confirmed the significant results in the reduction of total cholesterol, LDL (the “bad”) and of a significant secondary factor: Waist size. Volunteers with normal (65) and moderately high (67) cholesterol levels consumed normal and high oleic olive pomace or sunflower oil. Only those who consumed the product from the olive grove received the main benefits.

“The reduction in waist circumference didn’t surprise us either, as this is related to the olive oil itself and the quality of its high-oleic monounsaturated fat, which contributes to less belly fat. It is also necessary to consider the series of minor components of olive pomace oil that reinforce various mechanisms. It is a very interesting marker for all people with a predisposition to obesity and one of the most monitored as it is associated with a high cardiovascular risk. The results were significant and very consistent in both populations with normal cholesterol and with hypercholesterolemia,” says Mateos Briz.

According to Bravo Clemente, these groups of participants were selected because they are people whose cholesterol levels are normal, which constitutes healthy consumers, or moderately high, a circumstance that can be corrected through diet. In this way, people with high cholesterol who need pharmacological treatment to regulate it were excluded.

Consumption of olive pomace oil has also been shown to be beneficial in type 2 diabetes mellitus when high levels of glucose or sugar in the blood can be controlled through diet and exercise. The results of the study show that the use of olive fat lowers insulin levels, has positive effects on the insulin resistance index and increases tissue sensitivity, cells’ response to the hormone and to glucose.

quantity and variety

To get the benefits, the average amount that needs to be consumed per day must be 45 grams, about four tablespoons, which should represent 20% of the energy provided by the diet, which is in terms of intake of this type of monounsaturated fat is desirable.

According to both researchers, the point is not to prefer the consumption of one oil over another, but to complement them, to use each for what requires a better experience. “It’s like wine, you don’t always drink red,” explains Mateos Briz.

In this way, extra virgin olive oil would be better suited for consumption raw and in foods that require a more intense flavor, while olive pomace oil would be more suitable for culinary processes that require a milder flavor. Also for pastries, as a butter substitute, in stews or in fried dishes. “Olive pomace oil has unbeatable properties there,” defends Bravo Clemente.

The researcher adds that, in relation to the industrial manufacture of sweets, where palm oil is widespread, despite the provision of highly saturated fats, which are negative from a nutritional point of view, studies are being carried out on the use of olive pomace oil.

Results from ICTAN’s work are consistent with others outside of this center and have previously been performed in mice. This is the case of the research conducted by Carmen Claro Cala from the Department of Pharmacology, Pediatrics and Radiology at the University of Seville and Rosalía Rodríguez from the International University of Catalonia. Their study, published in the MDPI journal Nutrients, also links olive pomace oil consumption to reduced obesity, body fat, liver inflammation and insulin resistance.

Another study, whose principal investigator is Javier Sánchez Perona, a food and health scientist at the Institute of Fat (CSIC), indicated that oleanolic acid, α-tocopherol and β-sitosterol, bioactive compounds in olive pomace oil, prevent the overactivation of microglia, a group of cells in the central nervous system whose main function is defence, and reduce neuronal inflammation associated with Alzheimer’s.

The work presented this Thursday was sponsored by Oriva, a multi-industry and non-profit entity in the field of olive pomace oil, founded in 2015 to promote knowledge and scientific study on the product. “We are committed to independent, rigorous and ongoing research, and we collaborate with our country’s most important institution in this field, the Higher Council for Scientific Research,” said José Luis Maestro Sánchez-Cano, President of Oriva, in a company statement .

You can write and follow us at [email protected] THE COUNTRY Health and well-being on Facebook, Twitter and Instagram.