Health Benefits of Olive Oil: Cancer

Virgin olive oil protects against breast cancer

Breast cancer is the most common type of cancer in Western countries. Research carried out with animal models demonstrate that a diet rich in fats is directly related to the incidence of cancer. Some types of fats however can play a protective role against the development of these tumors. Such is the case of virgin olive oil, rich in oleic acid, a mono-unsaturated fatty acid, and containing several bioactive compounds such as antioxidants. A moderate and regular intake of virgin olive oil, characteristic of the Mediterranean diet, is associated with low incidences of specific types of cancer, including breast cancer, as well as with having a protective role against coronary diseases and other health problems.

The study carried out by UAB researchers decoded the mechanisms operating within the tumor cell and induced by the intake of olive oil, in comparison to those activated by corn oil, rich in n-6 polyunsaturated fatty acids, which increase the aggressiveness of tumors.

Scientists demonstrated that virgin olive oil is associated with higher incidences of benign breast tumors and at the same time with a decrease in the activity of the p21Ras oncogene, which spurs uncontrolled cell proliferation and stimulates the growth of tumors. In addition, olive oil suppresses the activity of some proteins, such as the AKT, essential for the survival of cells since they prevent apoptosis, the cell's "suicide" programme. Between proliferation and apoptosis in tumor cells, these effects tip the balance towards cell death, thereby slowing the growth of tumors.

Another result obtained by researchers is the protection of DNA in the cell nucleus. Cells from animals fed a diet rich in virgin olive oil contained less DNA lesions than those fed a control diet.

Scientists of the UAB Breast Cancer Study Multidisciplinary Group (GMECM) have spent over twenty years working to determine the effects fats have on breast cancer, and in particular the effects of virgin olive oil. Previous studies of the group revealed the beneficial effects of this component of the human diet on the clinical conduct of mammary tumors and on their histological grade (malignancy). Scientists also described several molecular mechanisms producing these effects and in 2004 the same group was the one to identify the four genes involved in the effects dietary fats have on experimental breast cancer. The mechanism recently discovered was published in the journal Carcinogenesis.

Olive oil has a significant impact on cancer rates 

If you want to avoid developing cancer, then you might want to add eating more olive oil to your list of New Year's resolutions. In a study to be published in the January 2007 issue of The FASEB Journal, scientists from five European countries describe how the anti-cancer effects of olive oil may account for the significant difference in cancer rates among Northern and Southern Europeans.

The authors drew this conclusion based on the outcomes of volunteers from Denmark, Finland, Germany, Italy, and Spain, who consumed 25 milliliters (a little less than a quarter cup) of olive oil every day for three weeks. During this time, the researchers examined urine samples of the subjects for specific compounds known to be waste by-products of oxidative damage to cells, a precursor to cancer. At the beginning of the trial, the presence of these waste by-products was much higher in Northern European subjects than their Southern European counterparts. By the end of three weeks, however, the presence of this compound in Northern European subjects was substantially reduced.

"Determining the health benefits of any particular food is challenging because of it involves relatively large numbers of people over significant periods of time," said lead investigator Henrik E. Poulsen, M.D. of Rigshospitalet, Denmark. "In our study, we overcame these challenges by measuring how olive oil affected the oxidation of our genes, which is closely linked to development of disease. This approach allows us to determine if olive oil or any other food makes a difference. Our findings must be confirmed, but every piece of evidence so far points to olive oil being a healthy food. By the way, it also tastes great."

Another interesting finding in the study suggests that researchers are just beginning to unlock the mysteries of this ancient "health food." Specifically, the researchers found evidence that the phenols in olive oil are not the only compounds that reduced oxidative damage. Phenols are known antioxidant compounds that are present in a wide range of everyday foods, such as dark chocolate, red wine, tea, fruits, and vegetables. Despite reducing the level of phenols in the olive oil, the study's subjects still showed that they were receiving the same level of health benefits.

"Every New Year people make resolutions that involve eating less fat to improve their health," said Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal. "This academically sound, practically useful study shows that what you eat is just as important as how much you eat. No wonder Plato taught wisdom in an olive grove called Academe."

Prevent cancer, use olive oil

If you want to avoid developing cancer, then you might want to add eating more olive oil to your list of New Year's resolutions. In a study to be published in the January 2007 issue of The FASEB Journal, scientists from five European countries describe how the anti-cancer effects of olive oil may account for the significant difference in cancer rates among Northern and Southern Europeans.

The authors drew this conclusion based on the outcomes of volunteers from Denmark, Finland, Germany, Italy, and Spain, who consumed 25 milliliters (a little less than a quarter cup) of olive oil every day for three weeks. During this time, the researchers examined urine samples of the subjects for specific compounds known to be waste by-products of oxidative damage to cells, a precursor to cancer. At the beginning of the trial, the presence of these waste by-products was much higher in Northern European subjects than their Southern European counterparts. By the end of three weeks, however, the presence of this compound in Northern European subjects was substantially reduced.

"Determining the health benefits of any particular food is challenging because of it involves relatively large numbers of people over significant periods of time," said lead investigator Henrik E. Poulsen, M.D. of Rigshospitalet, Denmark. "In our study, we overcame these challenges by measuring how olive oil affected the oxidation of our genes, which is closely linked to development of disease. This approach allows us to determine if olive oil or any other food makes a difference. Our findings must be confirmed, but every piece of evidence so far points to olive oil being a healthy food. By the way, it also tastes great."

Another interesting finding in the study suggests that researchers are just beginning to unlock the mysteries of this ancient "health food." Specifically, the researchers found evidence that the phenols in olive oil are not the only compounds that reduced oxidative damage. Phenols are known antioxidant compounds that are present in a wide range of everyday foods, such as dark chocolate, red wine, tea, fruits, and vegetables. Despite reducing the level of phenols in the olive oil, the study's subjects still showed that they were receiving the same level of health benefits.

"Every New Year people make resolutions that involve eating less fat to improve their health," said Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal. "This academically sound, practically useful study shows that what you eat is just as important as how much you eat. No wonder Plato taught wisdom in an olive grove called Academe."

Extra virgin olive oil extra protective 

Eating a diet rich in the phenolic components of virgin olive oil represses several pro-inflammatory genes. Researchers writing in the open access journal BMC Genomics suggest that this partly explains the reduced risk of cardiovascular disease seen in people who eat a 'Mediterranean diet'.

Francisco Perez-Jimenez from the University of Cordoba, Spain, led a team of researchers who studied the effects of eating a breakfast rich in phenol compounds on gene expression in 20 patients with metabolic syndrome, a common condition associated with increased risk of cardiovascular disease and type 2 diabetes. The study participants ate controlled breakfasts, and for six weeks before the study they had to avoid all drugs, vitamin tablets and other supplements. Perez-Jimenez said, "We identified 98 differentially expressed genes when comparing the intake of phenol-rich olive oil with low-phenol olive oil. Several of the repressed genes are known to be involved in pro-inflammatory processes, suggesting that the diet can switch the activity of immune system cells to a less deleterious inflammatory profile, as seen in metabolic syndrome."

Phenols are micronutrients of olive oil; the extra-virgin varieties have a particularly large phenol fraction. According to Perez-Jimenez, "These findings strengthen the relationship between inflammation, obesity and diet and provide evidence at the most basic level of healthy effects derived from virgin olive oil consumption in humans. It will be interesting to evaluate whether particular phenolic compounds carry these effects, or if they are the consequence of a synergic effect of the total phenolic fraction".