Adding olive oil to foods in a Mediterranean diet can reduce the risk of breast cancer in women by two-thirds, according to a new study published this month.
The Mediterranean diet, chosen as the best for 2023, includes a combination of foods either grown or raised in countries including Italy and Greece, and advocates replacing butter with oils and reducing meat consumption in favor of more fish. Also, one should eat lots of fruits and vegetables, legumes and nuts.
In the current study, researchers compared two groups of women, with one group assigned to a Mediterranean diet with olive oil and nuts. The second received a recommendation to adhere to a general low-fat diet.
Mediterranean diet helps lower risk of breast cancer
The study found that women aged 60 to 80 who followed a Mediterranean diet supplemented with extra-virgin olive oil had a 68% lower risk of developing malignant breast cancer compared to those who followed the low-fat diet. Yet, those who followed the Mediterranean diet and ate nuts showed a non-significant risk reduction.
Out of 4,282 women in Spain surveyed between 2003 and 2009, there were 35 new cases of malignant breast cancer. The average woman studied was 67.7 years old with a BMI of 30.4; most entered menopause before age 55.
The lead author, Dr. Miguel A. Martínez-González, said that the experiments' results show the beneficial effects of the Mediterranean diet. By adding virgin olive oil, it can be a factor in the primary prevention of breast cancer.
He clarified, though, that these results need to be confirmed by long-term studies with a higher number of cases. The authors also said that they couldn't determine if the health benefits derived from extra virgin olive oil alone or from eating it with other foods which are part of the Mediterranean diet.
In any case, Martinez-Gonzalez stated that preventive strategies are the most logical way to prevent cancer. Mitchell Katz, deputy editor of JAMA Internal Medicine which published the study, wrote that, of course, no study is perfect.
The current study has a small number of results with only 35 cases of breast cancer. All participants were Caucasian, past menopause age and were at high risk of cardiovascular disease. Yet following a Mediterranean diet of plant foods, fish and extra virgin olive oil is known to reduce the risk of cardiovascular disease and is safe to consume, and it may prevent some cases of breast cancer.