Olive tree: benefits, dosage, contraindications
Scientific name(s)
Olea europaea
Family or group:
Plants
Active ingredients:
Oleic acid
Oleuropein
Hydroxytyrosol
Indications
Scoring methodology
EFSA approval.
Oxidative stress ✪✪✪✪✪
Olive oil and its leaves help improve oxidative parameters in the blood, notably thanks to oleuropein. The claim can only be used for olive oil that contains at least 5 mg of hydroxytyrosol and its derivatives (for example, the oleuropein complex and tyrosol) per 20 g of olive oil.
Posologie
Oral: leaf, fruit
500 - 1000 mg
oil, standardized extract
Olive Oils High in Phenolic Compounds Modulate Oxidative/Antioxidative Status in Men
Scientific Opinion on the substantiation of health claims related to polyphenols in olive and protection of LDL particles from oxidative damage
Olive Oils High in Phenolic Compounds Modulate Oxidative/Antioxidative Status in Men
High blood pressure ✪✪✪✪✪
The consumption of a modified diet including large amounts of extra-virgin olive oil for 6 months, in conjunction with conventional treatments for hypertension, can significantly improve blood pressure. Oral intake of an olive leaf extract also appears to lower blood pressure in patients with hypertension. An olive leaf extract of 400 mg four times daily for 3 months was used. Extra-virgin olive oil 30-40 grams per day for one year was used as part of the diet.
Posologie
Oral: leaf, fruit
1600 mg
hydroalcoholic extract, dry extract
Plasma Lipids, Erythrocyte Membrane Lipids and Blood Pressure of Hypertensive Women After Ingestion of Dietary Oleic Acid From Two Different Sources
Olive Oil and Reduced Need for Antihypertensive Medications
[A Clinical Trial of a Titrated Olea Extract in the Treatment of Essential Arterial Hypertension]
Olive (Olea Europaea) Leaf Extract Effective in Patients With stage-1 Hypertension: Comparison With Captopril
Olive (Olea Europaea L.) Leaf Polyphenols Improve Insulin Sensitivity in Middle-Aged Overweight Men: A Randomized, Placebo-Controlled, Crossover Trial
Food Supplementation With an Olive (Olea Europaea L.) Leaf Extract Reduces Blood Pressure in Borderline Hypertensive Monozygotic Twins
Dyslipidemia ✪✪✪✪✪
Increasing olive oil consumption instead of saturated fats may reduce total cholesterol. However, any reduction in low-density lipoprotein (LDL) cholesterol is small. Moreover, a meta-analysis of clinical research showed that olive oil is less effective than other oils at reducing total cholesterol and LDL cholesterol.nnOverall, olive leaf extracts and olive oil may be beneficial in dyslipidemia, particularly with elevated LDL-C, in combination with an appropriate diet and/or cholesterol-lowering treatment.nn
Posologie
By mouth: leaf, fruit
400 - 900 mg
olive leaf extract, oil
Postprandial LDL phenolic content and LDL oxidation are modulated by olive oil phenolic compounds in humans.
Protection of LDL from oxidation by olive oil polyphenols is associated with a downregulation of CD40-ligand expression and its downstream products in vivo in humans.
Antioxidant effect of virgin olive oil in patients with stable coronary heart disease: a randomized, crossover, controlled, clinical trial.
Olive Oils High in Phenolic Compounds Modulate Oxidative/Antioxidative Status in Men
Changes in the Phenolic Content of Low Density Lipoprotein After Olive Oil Consumption in Men. A Randomized Crossover Controlled Trial
Effects of Differing Phenolic Content in Dietary Olive Oils on Lipids and LDL Oxidation--A Randomized Controlled Trial
Olive (Olea Europaea) Leaf Extract Effective in Patients With stage-1 Hypertension: Comparison With Captopril
Olive (Olea Europaea L.) Leaf Polyphenols Improve Insulin Sensitivity in Middle-Aged Overweight Men: A Randomized, Placebo-Controlled, Crossover Trial
Type 2 diabetes ✪✪✪✪✪
Population research has shown that consumption of the highest amount of olive oil for approximately 6 to 22 years is associated with a 16% reduction in the risk of developing type 2 diabetes compared with the lowest amount. This inverse association persists for doses up to 15-20 g per day. nnA meta-analysis of clinical research also shows that consuming olive oil for 2 weeks to 4 years reduces HbA1c and fasting blood glucose compared with control in patients with diabetes. The effect of olive oil on HbA1c is similar to the effects of fish oil and polyunsaturated fatty acid oils, and slightly greater than the effects of a low-fat diet nnOlive leaf extract is also indicated for insulin resistance, in combination with an appropriate diet and/or antidiabetic treatment.nn
Posologie
Oral: leaf, fruit
400 - 900 mg
olive leaf extract, oil
Olive leaf extract as a hypoglycemic agent in both human diabetic subjects and in rats.
Olive Oil in the Prevention and Management of Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Cohort Studies and Intervention Trials
Olive (Olea europaea L.) leaf polyphenols improve insulin sensitivity in middle-aged overweight men: a randomized, placebo-controlled, crossover trial.
Breast cancer ✪✪✪✪✪
A meta-analysis of epidemiological research, as well as individual observational studies, show that a higher dietary intake of olive oil is associated with a lower risk of breast cancer in women.nn
Posologie
Oral: fruit, leaf
oil
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
Consumption of Olive Oil and Specific Food Groups in Relation to Breast Cancer Risk in Greece
Dietary Fat, Olive Oil Intake and Breast Cancer Risk
Cardiovascular diseases ✪✪✪✪✪
Olive oil rich in oleic acid reduces the risk of coronary heart disease. Overall, there is low to moderate quality evidence that olive oil provides a modest benefit for the primary prevention of cardiovascular disease (CVD). However, the majority of positive findings come from observational research; evidence from clinical research is less certain. The evidence regarding olive oil for the secondary prevention of cardiovascular disease is unclear, as clinical research is limited or inconsistent. Research has shown that a high dietary intake of olive oil (54 g/day; about 4 tablespoons) is associated with an 82% reduction in the risk of a first myocardial infarction compared with lower dietary intake. In addition, exclusive use of olive oil is associated with a 90% reduction in the risk of developing CVD compared to the absence of olive oil in the diet. Olive oil consumption is associated with reductions in cardiovascular disease risk factors, including decreases in blood pressure and cholesterol.
Posologie
Oral: leaf, fruit
23 - 54 g
oil
The Effect of Polyphenols in Olive Oil on Heart Disease Risk Factors: A Randomized Trial
Olive Oil Consumption and 10-year (2002-2012) Cardiovascular Disease Incidence: The ATTICA Study
Risk of first non-fatal myocardial infarction negatively associated with olive oil consumption: a case-control study in Spain.
Effects of Differing Phenolic Content in Dietary Olive Oils on Lipids and LDL Oxidation--A Randomized Controlled Trial
Atherosclerosis ✪✪✪✪✪
The phenolic compounds in olive oil, such as hydroxytyrosol, are responsible for its antioxidant properties. Hydroxytyrosol not only scavenges radicals, but also stimulates synthesis and increases the activity of endogenous antioxidant enzymes. It limits LDL lipid peroxidation, which has beneficial effects in the prevention of atherosclerosis. nnAccording to a double-blind randomized study, the consumption of hydroxytyrosol and punicalagin (extracted from pomegranates) for 8 weeks could help reduce atherosclerotic markers. nn105 people aged 45 to 65 years consumed daily 9.9 mg of hydroxytyrosol, combined with 195 mg of punicalagin. This supplementation showed anti-atherogenic effects, resulting in a decrease in blood pressure as well as a decrease in circulating oxidized LDL cholesterol levels.nn
Posologie
Oral route: leaf, fruit
20 g
oil, standardized extract
Synergies
Metabolic syndrome ✪✪✪✪✪
Clinical research shows that taking four capsules of olive leaf extract providing 51.1 mg of oleuropein and 9.7 mg of hydroxytyrosol per day for 12 weeks improves insulin sensitivity by 15% compared to placebo in middle-aged overweight men at risk of metabolic syndrome.
Posologie
By mouth: leaf, fruit
400 mg
standardized extract
Cardiovascular benefits of tyrosol and its endogenous conversion into hydroxytyrosol in humans. A randomized, controlled trial
Beneficial effects of dietary supplementation with olive oil, oleic acid, or hydroxytyrosol in metabolic syndrome: Systematic review and meta-analysis
Olive (Olea Europaea L.) Leaf Polyphenols Improve Insulin Sensitivity in Middle-Aged Overweight Men: A Randomized, Placebo-Controlled, Crossover Trial
Water retention ✪✪✪✪✪
The EMA indicates that olive leaves are used to promote renal elimination of water in mild cases of water retention.
Posologie
By mouth: leaf, fruit
630 - 1375 mg
dry extract
Properties
Antihypertensive
A human study compared the effect of an olive extract and captopril (a drug for hypertension) in patients with stage I hypertension. Administration of the extract produced a reduction in systolic and diastolic blood pressure comparable to that observed with the reference drug.nnIt is thought that the hypotensive action is probably not due exclusively to the single molecule oleuropeoside. This effect may be related to a vasodilatory action produced by the olive leaf extract. The macerate most effective for hypertension, the coronary arteries and other arteries is the glycerol-alcoholic macerate of the leaves.
Usages associés
Cholesterol-lowering
A study explored the cholesterol-lowering effects of olive leaf extract in rats fed a high-cholesterol diet. The experiment showed that olive leaf extract significantly reduced total cholesterol and LDL-cholesterol levels in the rats' serum, without notably affecting HDL-cholesterol and triglyceride levels. These results suggest that olive leaf extract could be beneficial for reducing atherogenic indices, i.e., risk factors related to atherosclerosis.nnResearch suggests that compounds such as oleuropein, present in olive leaves, may play a key role due to their antioxidant and anti-inflammatory properties. These properties could contribute to cholesterol reduction by inhibiting the oxidation of low-density lipoproteins (LDL), a process involved in the development of atherosclerosis.nn
Usages associés
Cardiovascular
People use olive oil to prevent cardiovascular diseases and atherogenesis because it appears to reduce certain cardiac risk factors. The phenolic compounds present in olive oil appear to have antioxidant, vasodilatory, and antiplatelet properties. The compounds act as free radical scavengers, inhibiting platelet aggregation and thromboxane release. nnOlive oil appears to increase the resistance of low-density lipoprotein (LDL) cholesterol to oxidation and thus may reduce its contribution to atherogenesis. It also appears to improve endothelial function in patients with hypercholesterolemia. Olive oil may lower blood pressure and decrease postprandial activity of coagulation factor VII. nnPreliminary research suggests that olive oil may reduce aortic wall thickness in hypertensive animals; however, this occurs to a lesser extent than with fish oils. Olive oil also appears to modestly reduce cardiomyocyte death, which increases in left ventricular hypertrophy.nn
Usages associés
Antioxidant
According to laboratory research, olive leaf extract has antioxidant effects thanks to oleuropein. Studies have shown the protective role of olive extracts in preventing reperfusion injury following cardiac ischemia, injuries mainly generated by free radicals. New studies show that oleuropein could prevent ethanol-induced damage to the gastric mucosa in rats by increasing the activity of antioxidant defense enzymes (SOD, catalase, GPx) as well as decreasing lipid peroxidation.
Usages associés
Anti-inflammatory
Olive oil may have anti-inflammatory effects by decreasing concentrations of pro-inflammatory omega-6 fatty acids and increasing concentrations of anti-inflammatory omega-3 fatty acids. Metabolites of oleic acid, a monounsaturated omega-9 fatty acid in olive oil, appear to competitively inhibit the production of inflammatory prostaglandins and leukotrienes from omega-6 fatty acids. Metabolites of oleic acid may also suppress the production of inflammatory cytokines. Olive oil also contains oleocanthal, which may be responsible for some of olive oil's anti-inflammatory effects. This compound shares certain pharmacological properties with nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen. Oleocanthal inhibits both cyclooxygenase (COX) 1 and 2. However, it does not inhibit lipoxygenase. Extra virgin olive oil provides approximately 200 mcg of oleocanthal per ml of oil. It is thought that about 60% to 90% of oleocanthal is absorbed after ingestion.
Usages associés
Vascular effect
The extract of olive leaves is a direct peripheral vasodilator, particularly of peripheral arterioles. Oleanolic acid has anti-atherosclerotic and antioxidant effects demonstrated in in vivo studies. Leaf extracts have also been found to be antiarrhythmic.
Usages associés
Hypoglycemic
In humans, the effects of olive leaf extract on the insulin response are likely due to improvements in pancreatic beta-cell function and a reduction in inflammatory mediators.
Usages associés
Antibacterial
Olive leaf extract is active in vitro against certain germs (Staphylococcus, Streptococcus, Haemophilus, Pseudomonas...). It is also active in certain viral conditions. This effect is mainly attributable to iridoids (oleuropeoside, ligustroside, hydroxytyrosol) and triterpenes (oleanolic acid).
Safe dosage
Adults aged 18 years and older: 400 mg - 1375 mg
- Herbal tea: 10 g of fresh leaves or 5 g of dried leaves in 150 mL of water as a decoction twice a day (morning and evening). - Crushed dried leaves for infusion: single dose: 6-10 g up to 3 times per day. Daily dose: 6-30 g. - Dried leaves in powder form: Single dose: 275 mg 3-5 times per day or 200-300 mg 2 to 3 times per day. Daily dose: 630-1375 mg.
Interactions
Médicaments
Antiplatelet agents/Anticoagulants: moderate interaction
In vitro evidence and preliminary human research suggest that olive oil has antiplatelet effects. Theoretically, concomitant use of olive oil and anticoagulants or antiplatelet agents may increase the risk of bleeding in some people. Some of these medications include aspirin, heparin, warfarin, etc...
Antidiabetic: moderate interaction
Theoretically, concomitant use of olive could enhance blood sugar–lowering effects. Monitor blood glucose closely.
Antihypertensive: moderate interaction
Theoretically, concomitant use of olive may enhance the blood pressure–lowering effect. Some antihypertensive medications include Captopril, enalapril, Losartan, valsartan, Diltiazem, Amlodipine...
Precautions
Pregnant women: use with caution
Insufficient reliable information; avoid using amounts higher than those normally found in foods.
Breastfeeding woman: use with caution
Insufficient reliable information; avoid using amounts greater than those commonly found in foods. nn
Heart disorders: use with caution
Patients with heart disease or kidney failure should consult a physician before taking olive leaves.nn
Renal insufficiency: use with caution
Patients with heart disease or kidney failure should consult a physician before taking olive leaves.nn
