Olive oil truly is liquid gold with its many health benefits. Considered the most important component of the traditional Mediterranean diet, this extraordinary fruit juice and its effects are still not fully understood. Yet some of the ways olive oil can preserve and improve human health have been firmly established.
Here are the five most scientifically supported health benefits of olive oil today.
1. It Can Help Lower Your “Bad” Cholesterol
Low Density Lipoprotein (LDL), also known as the body’s “bad cholesterol,” transports and deposits cholesterol in the tissues and arteries, which can eventually cause plaque and block the artery. Monounsaturated fats can lower LDL thus protecting against atherosclerosis (hardening of the arteries). Plus, monounsaturated fat does not negatively affect the levels of High Density Lipoproteins (HDL) known as the “good cholesterol,” which carries all cholesterol away from the arteries. High levels of HDL are associated with a decreased risk of heart disease.
Olive oil is one of the best sources of monounsaturated fats and has the advantage of being less susceptible to oxidation. In addition, oleic acid, a fatty acid abundant in olive oil, appears to also protect from oxidation of LDL.
It is important to mention, to achieve this reduction in bad cholesterol you cannot just add olive oil to a diet high in saturated and trans fats and expect a miracle. You must replace the unhealthy fats with olive oil in combination with a Mediterranean-style diet.
2. Olive Oil Can Help Lower Your Blood Pressure
Several studies for different age groups, and with a large number of participants, have found the consumption of olive oil is associated with a decrease in blood pressure.
The SUN study with over 6,000 participants found olive oil intake reduced the incidence of hypertension in men, while another Spanish study published in the American Journal of Hypertension found a diet containing polyphenol rich olive oil reduced blood pressure in young women with mild hypertension.
Results from the Greek component of the EPIC study (European Prospective Investigation into Cancer and Nutrition) which included over 28,500 volunteers concluded olive oil intake is inversely associated with both systolic and diastolic blood pressure. While it appears the polyphenols in the olive oil may be responsible for this action, researchers have demonstrated that oleic acid; a fatty acid in olive oil may also induce this lowering effect.
3. Eating Olive Oil Can Help Prevent Cancer
Olive oil consumption has been associated with a reduced risk of cancer. A review conducted last year by Greek researchers from the University of Athens looked at 19 observational studies, with over 36,000 participants, and found higher rates of olive oil consumption were associated with lower odds of having any type of cancer. Another review of 25 epidemiological studies concluded that “preferring olive oil to other added lipids, particularly those rich in saturated fats, can decrease the risk of upper digestive and respiratory tract neoplasms, breast and, possibly, colorectal and other cancer sites.”
4. It Protects from Oxidative Damage
Oxidative damage occurs when your body doesn’t have enough antioxidants to protect against the damaging free radicals. Apart from the beneficial monounsaturated fats in olive oil and specifically oleic acid, olive oil also contains polyphenols. Polyphenols are phytochemicals, components that have antioxidant activity. The specific type of polyphenols found in olive oil appear to protect the oxidation of LDL cholesterol in the body.
Researchers for the Eurolive Study Group found that consumption of olive oil at real-life doses of about 2 tablespoons per day improved the fatty acid profile in LDL, associated with a reduction of the oxidative damage to lipids. It appears that oxidized LDL is a major contributor to atherogenesis; the process of plaque buildup in the arteries that eventually can lead to atherosclerosis (hardening of the arteries).
This is an approved claim for olive oil in the European Union: “Olive oil polyphenols contribute to the protection of blood lipids from oxidative stress.”
It is important to note that only polyphenol rich extra virgin olive oils may have this effect, not refined olive oil, which does not contain these substances.
5. Olive Oil Can Help Cognitive Function
Although olive oil is better known for its protection against heart disease and cancer, there is an emerging amount of research regarding the effect of olive oil on cognitive function and, specifically, on cognitive decline associated with aging.
Generally, the type of fat consumed can affect cognitive function. A study from Brigham and Women’s Hospital, a teaching affiliate of Harvard Medical School, analyzed data from 6,000 women over the age of 65, a subset of the Women’s Health Study. They found women who consumed the highest amount of monounsaturated fats, which can be found in olive oil, had better patterns of cognitive scores over time.
But it appears olive oil specifically has a protective effect. Results from the Three City Study, an ongoing multicenter study of vascular risk factors for dementia using information from almost 7,000 participants, showed individuals who had moderate to intensive use of olive oil had lower odds of cognitive deficit for verbal fluency and visual memory compared to individuals who had never used olive oil.
How much of a good thing?
When looking at the different studies in regards to the protective effect of olive oil for various conditions the amount generally ranges between 25 and 40 grams per day, or about 2-3 tablespoons.
In Health and Happiness,
Kelly Harrington, MS, RDN
Registered Dietitian Nutritionist for Healthy Goods
References:
1. High-monounsaturated fatty acid diets lower both plasma cholesterol and triacylglycerol concentrations http://ajcn.nutrition.org/content/70/6/1009.full
2. Effects of Monounsaturated Fatty Acids on Cardiovascular Risk Factors: A Systematic Review and Meta-Analysis http://www.karger.com/Article/FullText/334071
3. The effect of olive oil polyphenols on antibodies against oxidized LDL. A randomized clinical trial. http://www.clinicalnutritionjournal.com/article/S0261-5614(11)00029-X/fulltext
4. Elevated Circulating LDL Phenol Levels in Men Who Consumed Virgin rather Than Refined Olive Oil are Associated with Les Oxidation of Plasma LDL. http://jn.nutrition.org/content/140/3/501.long
5. Low Fat and High Monounsaturated Fat Diets Decrease Human Low Density Lipoprotein Oxidative Susceptibility In Vitro. http://jn.nutrition.org/content/131/6/1758.full
6. Olive oil consumption and reduced incidence of hypertension: The SUN study. http://link.springer.com/article/10.1007%2Fs11745-004-1352-x?LI=true
7. Olive oil, the Mediterranean diet, and arterial blood pressure: the Greek European Prospective Investigation into Cancer and Nutrition (EPIC) study. http://ajcn.nutrition.org/content/80/4/1012.abstract
8. Olive oil consumption and reduced incidence of hypertension: The SUN (Seguimiento University of Navarra) study. http://link.springer.com/article/10.1007%2Fs11745-004-1352-x?LI=true
9. Oleic acid content is responsible for the reduction in blood pressure induced by olive oil. http://www.pnas.org/content/105/37/13811.abstract
10. Virgin olive oil reduces blood pressure in hypertensive elderly subjects http://www.clinicalnutritionjournal.com/article/PIIS026156140400024X/fulltext
11. Olive oil intake is inversely related to cancer prevalence: a systematic review and a meta-analysis of 13,800 patients and 23,340 controls in 19 observational studies. http://www.lipidworld.com/content/10/1/127
12. Olive oil and Cancer Risk: an Update of Epidemiological Findings through 2010 http://www.benthamscience.com/cpd/contabs/contents.php?JCode=CPD&Vol=00000017&Iss=00000008#3167024
13. Olive Oil and Cognition: Results from the Three-City Study http://www.hal.inserm.fr/docs/00/41/39/95/PDF/inserm-00413995_edited.pdf
14. Dietary fat types and 4-year cognitive change in community-dwelling older women. http://onlinelibrary.wiley.com/doi/10.1002/ana.23593/abstract
Article courtesy of Olive Oil Times.
