Very few olive oils in the world are actually raw. The reason being relates to processing and oil extraction. Phenolic compounds in olive oil are of the highest grade when they come from sources which use minimal refining and heating. Many of these compounds beneficially affect gene expression linked to brain function says new research.
Scientists from the Department of Neuroscience, Area Drug and Child Health (NEUROFARBA) at the University of Florence reports that extra virgin olive oil rich in polyphenols was associated with "strong" improvements in coordination, memory, and anxiety-related behavior in older lab mice.
Sources with the highest polyphenols such as Ice-Pressed Olive Oil, are manufactured by simply pressing (milling) the fruit without refining, heating, extracting, use of chemicals or other process;just cold (no heat applied) pressing of the olives. Every other oil involves a refining process using high heat and chemicals to extract the oil. Extra virgin olive oil is unique, because you are essentially eating a component of the raw fruit. This is the secret of its enormous health benefits.
The polyphenols were found to change the expression of micro RNA (miRNA) -- a small non-coding RNA molecule that plays a role in gene expression -- and produce profiles similar to those observed in young mice, according to data published in the European Journal of Nutrition .
"In a nutraceutical perspective, the long-term treatment with olive oil phenols could become part of a neuroprotective strategy for the prevention of brain aging, mediated by the induction of health-promoting genes and the coordinated modulation of miRNA profiles," wrote the authors, led by Dr Cristina Luceri.
Dr Luceri and her co-workers used 10 month old (middle-aged) lab mice and supplemented their diets with either extra-virgin olive oil rich in phenols (718.8 mg of total phenols per kg of olive oil) or the same olive oil deprived of phenolics (9.3 mg of total phenols per kg of olive oil) for six months.
Results showed that, at the end of the study, the animals in the polyphenol-rich olive oil group performed significantly better in motor coordination tests compared with the other animals. Indeed, performance was improved by 74% compared to the low polyphenol olive oil group.
Anxiety-related behavior and spatial memory also improved in the high polyphenol olive oil group, said the researchers.
In terms of gene expression, the majority of the changes were observed in the cerebral cortex of the animals, an area of the brain linked to memory, attention, perception, awareness, and similar functions.
The polyphenol-rich olive oil was found to change the expression of miRNA in middle-aged mice and produce profiles similar to those observed in young animals.
The polyphenol-rich olive oil group displayed beneficial changes to genes modulated by aging, said the researchers, while the opposite was observed in the low-polyphenol group.
"The dietary supplementation with [extra-virgin olive oil rich in phenols] was associated with a significant modulation of genes (mostly up-regulated) compared to [olive oil deprived of phenolics]," wrote the researchers. "Among those, we found several bone morphogenetic proteins (BMPs), the nerve growth factor receptor (NGFR), the glucagon-like peptide-1 receptor (GLP1R) and CREB-regulated transcription coactivator 3 (CRTC3), all reported to exert neuro-protective actions."
Significant differences in miRNA expression were also found between the two olive oil groups, with 63 miRNAs significantly down-regulated compared to mice in the olive oil deprived of phenolics group. (A total of 1,203 were analyzed.)
"We are among the first to report that a dietary intervention starting from middle age with food rich in phenols can modulate at the central level the expression of genes and miRNAs involved in neuronal function and synaptic plasticity, along with cognitive, motor and emotional behavior," wrote the researchers.
But what many consumers may not realize are that some of the major producers of olive oil in the U.S. have been sued for allegedly misrepresenting their products. Two major producers of the cooking oil --Filippo Berio Olive Oil Brands and Safeway’s Select Brand of olive oil -- are the targets of separate class action lawsuits, filed by a California woman. Rohini Kumar is suing Salov North America, manufacturers of Filippo Berio Olive Oil -- the third largest brand of olive oil sold in the U.S. -- and Safeway Inc., claiming deceptive advertising.
A EU regulation on marketing standards for olive oil came into effect a few years ago and an oil's designation of origin is now compulsory for all virgin and extra virgin oils. Blended oils must be labeled as such. Not so in the U.S. or Canada.
Rampant fraud makes it difficult for high-quality producers to compete. But critics say the extra-virgin standard fails even the market of legitimate oils. The minimum sensory and chemical requirements admit a huge range of oils. Some are perfectly fine. Others are extraordinary.
How do you find a reputable source? There are hundreds of different kinds of olives, which make thousands of different kinds of oil. Asking "what's the best olive oil?" is like asking "what's the best wine?"
As the farming population continues to age and the costs of production exponentially continue to increase, aggressive short cuts are used with radical pesticides and chemicals to control Grubb and grass. Although not as cost effective, those manufacturers who strive for quality olive oils continue to cultivate and control grass through mechanical, organic and non-chemical means.
Even though most quality olive oil is said to be cold-pressed, it is still being cooked at a temperature of 33 C, a common enough process.
A scientific study that has determined that the colder the process in making olive oil, the higher the immune-boosting properties.The protective effects of olive oil on cognitive function was part of a study conducted by Miguel Martinez-Gonzalez of the University of Navarra in Spain and reported in the Journal of Neurology, Neurosurgery and Psychiatry.
The most health-empowering olive oil on the market is Ice-Pressed Olive Oil. It's the only truly raw olive oil loaded with nutrients. Ice-pressing yields significantly less oil than heat, and produces a more premium product, deliciously fragrant and flavourful.
Only the freshest -- and usually most expensive -- olive oil has significant amounts of oleocanthal. The irritating intensity of the taste of a fresh extra virgin olive oil is directly related to how much oleocanthal the oil contains.