In a recent study published in Nutrients, researchers conducted a scientific review to consolidate recent evidence on the preventive advantages of additional virgin olive oil (EVOO) on disease risk aspects.

Study: Is Extra Virgin Olive Oil the Critical Ingredient Driving the Health Advantages of a Mediterranean Diet? A Narrative Review. Image Credit: masa44/Shutterstock.com

Background

Mediterranean diets are plant-origin diets enriched with vegetables, fruits, nuts, legumes, whole grains, and moderate portions of fermented dairy products and fish, and are crucial for stopping chronic diseases.

EVOO, a typical ingredient within the Mediterranean food regimen, has been linked to a lowered risk of varied chronic diseases, comparable to heart problems, type 2 diabetes, cerebrovascular accidents, metabolic syndrome, cognitive function decline, and colorectal and breast tumors.

EVOO intake can reduce obesity risk, improving overall mortality. Nevertheless, there is restricted research on the precise every day amount of EVOO’s ability to enhance risk aspects for chronic diseases. In dietary recommendations, there may be little emphasis on distinguishing healthy fats like EVOO from other fats and oils.

Concerning the study

In the current systematic review, researchers compared the results of EVOO-containing meals on clinically significant cardiovascular and metabolic risk aspects for heart problems, type 2 diabetes, metabolic syndrome, and insulin resistance to those of non-EVOO diets.

For the period between January 2000 and December 2022, a scientific data search was performed using the Cochrane Library, Embase, and PubMed databases. Subsequently, the team carried out a narrative data synthesis.

The researchers only included randomized controlled trials (RCTs) with human participants that were published in peer-reviewed scientific journals in English and compared the cardiometabolic impacts of EVOO consumption to non-EVOO diets.

The team excluded In vitro or animal studies, those without randomization, those using only postprandial blood glucose measurements, testing olive oil’s phenolic compounds only, assessing the results of olive oil added to pills, olive oil with added components, using live oil, not known as of the extra virgin type, using pomace or refined olive oil exclusively, abstracts and presentations, and papers showing a possible shift in drugs which may affect any of the aspects to be investigated.

Studies evaluating ‘virgin olive oil’ with phenolic content specified were also considered. The lists of references from the papers identified through searches were also reviewed for extra relevant publications to incorporate. The Academy of Nutrition and Dietetics Quality Criteria Checklist (ANDQCC) was used to evaluate the standard of included RCTs.

Results

In total, 34 of the 281 retrieved articles met the eligibility criteria and were considered for the ultimate evaluation, all of which were rated as ‘positive’ based on the ANDQCC assessment. Several references were included, including subgroup analyses of the Prevencion con Dieta Med (PREDIMED) trial. EVOO outperformed alternative fats from food and low-fat (LF) diets in managing clinical indicators comparable to low-density lipoprotein-cholesterol (LDL-c) and blood pressure (BP), raising protective high-density lipoprotein-cholesterol (HDL-c) and improving glucose in addition to weight control.

The polyphenol content of EVOO, as a substitute of the quantity of monounsaturated fats, was likely liable for its helpful effects. In comparison with sunflower oil, EVOO reduced systolic BP (SBP) amongst hypertensive patients and healthy individuals. Certain phenols is perhaps critical for blood pressure reduction. One study reported SBP reduction with 161.0 mg/kg of phenol amongst hypertensive patients, whereas two studies showed no such effects with >300.0 mg/kg of phenol.

EVOO may decrease low-density lipoprotein cholesterol for initial levels exceeding 120.0 mg/dL and elevate HDL-c levels within the case of upper phenolic content, and diets containing every day EVOO were successful for reducing weight despite greater calorie intake than LF diets. Moreover, EVOO with ≥150.0 mg/kg of phenol could reduce LDL oxidation. EVOO can lower LDL-c levels for initial values above 120.0 mg/dL and elevate HDL-c levels with a rise within the phenolic content, and dietary regimes containing every day extra-virgin olive oil can effectively decrease body weight despite greater caloric intake than LF meals. Further, EVOO with ≥150.0 mg/kg of phenol could reduce LDL oxidation.

Few trials have included patients with high initial fasting blood glucose (FBG) or diabetes mellitus type 2; subsequently, the impact of extra-virgin olive oil on the FBG in relation to other dietary regimes is unclear. Day by day EVOO, then again, can enhance sensitivity to insulin as evaluated by the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) in comparison with LF diets.

The shortest period to health gains and the bottom every day quantity of EVOO obligatory to enhance blood pressure, HDL-c, and LDL-c were 21 days and 25.0 mL (almost two tablespoons) every day, respectively, with LDL-c and diastolic BP (DBP) potentially requiring >300.0 mg of phenol per kg for maximal advantages. EVOO’s ability to enhance the diagnostic biomarkers for congenital heart disease, i.e., BP, HDL-c, and LDL-c, could also be related to its ability to scale back CHD risk.

While diets enriched with vegetable seed oils may lower LDL more effectively than EVOO, a every day food regimen wealthy in EVOO will create healthier LDL since its particles will grow larger with a lower likelihood of being oxidized. Further, extra-virgin olive oil has been proven to scale back apoprotein B-100, implying fewer low-density lipoprotein particles. EVOO’s capability to scale back type 2 diabetes and metabolic syndrome risks is connected to its impact on HOMA-IR, insulin, and FBG, which reportedly improve following EVOO intake versus diets comprising polyunsaturated fat-rich oils (sunflower oil) or LF diets.

Conclusion

Overall, the findings showed that incorporating EVOO into dietary patterns within the Mediterranean food regimen can significantly reduce the chance of chronic disease. Regular consumption of EVOO, starting with two tablespoons every day, can improve various risk aspects in as few as three weeks. As well as, EVOO is a superior selection for reducing chronic disease risk in diets than other dietary fats or refined-type olive oil.

Cooking vegetables in Mediterranean countries with EVOO increases the absorption of fat-soluble carotenoids and enhances vegetable consumption. Future research should deal with EVOO with known phenol content, non-European participants with unhealthy risk aspects, and bigger sample sizes.