Olive Leaf Extract Benefits: Side Effects & How To Use

The olive tree has been closely connected to humans throughout history, providing immense value through its wood, fruit, and leaves.

Olive wood is used to make tables, chairs, firewood, and house frames, while olive fruit plays a vital role in cuisine, cosmetics, and medicine.

Many believe that olives are rich in nutrients, but in reality, olive leaves are just as beneficial. Notably, oleuropein—a key compound with powerful antioxidant and heart-protective properties—is found in much higher concentrations in olive leaves than in the fruit.

If you want to explore more about the incredible benefits of olive leaf extract, keep reading the following article!

What is Olive Leaf Extract?

Olive Leaf Extract (OLE) is a natural substance derived from the leaves of Olea europaea L. It shares similar properties with Extra-Virgin Olive Oil (EVOO), a key component of the Mediterranean diet known for its various health benefits.

Main Components [1]:

Polyphenols: The primary active compounds in OLE, which protect the plant from insects, bacteria, and fungi.

Oleuropein: The main phenolic component, which breaks down into beneficial compounds like oleuropein aglycone, oleacein, and hydroxytyrosol during the production of olive oil.

Traditional Uses of Olive Leaves [2]:

• Taken orally for stomach and intestinal ailments.
• Chewed for oral hygiene.
• Brewed from dried fruits and leaves to help with diarrhea and urinary tract infections.
• Consumed as a hot extract from fresh leaves for blood pressure reduction and diuretic effects.
• Made into a hot extract from dried plants to manage  bronchial asthma.

Olive Leaf Extract Benefits for Human Health

Benefits for Cardiovascular Health

Olive Leaf Extract (OLE) supports cardiovascular health mainly due to its blood pressure-lowering and antioxidant properties. The compound oleuropein in olive leaves helps regulate blood pressure, reducing the risk of hypertension – a major factor in cardiovascular diseases.

Additionally, oleuropein promotes insulin release in response to glucose and enhances peripheral glucose uptake, maintaining stable blood sugar levels.

This reduces diabetes-related complications and supports heart health. Its antioxidant properties also protect blood vessels from oxidative stress, improving overall cardiovascular health [2].

Studies show that OLE lowers blood pressure, induces vasodilation, and exhibits anti-arrhythmic effects in animals.

Clinical trials have demonstrated that it reduces systolic blood pressure and triglycerides in patients with stage 1 hypertension but has inconsistent effects on lipid metabolism and glucose levels in pre-hypertensive, overweight, or obese individuals.

Some studies report reduced inflammatory markers (IL-6, IL-8, TNF-alpha) with OLE use, with no adverse effects on liver or kidney function, although glucose and insulin levels were not significantly impacted [3].

However, animal experiments have many limitations, and human studies are needed for clearer results.

May Support Weight Management

Research on obese women suggests that supplementing with Olive Leaf Extract (OLE) alongside a calorie-restricted diet leads to greater reductions in weight, fat, blood sugar, bad cholesterol, and insulin resistance, while increasing good cholesterol and adiponectin levels compared to dieting alone.

This highlights OLE's effectiveness in improving obesity and metabolic risk factors [4].

“Based on results it seems that the addition of OLE to a hypocaloric diet for 8-week compared with a hypocaloric diet alone may be more effective in modifying obesity and metabolic risk factors.” - Extract from the study: Olive Leaf Extract Supplementation Combined with Calorie-Restricted Diet on Reducing Body Weight and Fat Mass in Obese Women: Result of a Randomized Control Trial

In high-calorie, sedentary obesity models in mice, OLE managed weight gain, enhanced lipolysis, and reduced cognitive decline and depressive behavior [3]. However, due to the limitations of animal studies, human research is necessary for more definitive results.

Potential in Enhancing the Immune System

Olive Leaf Extract (OLE) regulates immune responses by increasing CD8+ and NK cell counts, promoting IFN-γ production, and enhancing nitric oxide (NO) release, potentially supporting cancer defense and cardiovascular protection.

It also maintains a balance between regulatory T cells and Th17, showing potential in managing chronic inflammatory diseases and managing cardiovascular events [5].

OLE and its compounds Oleacin (OC) and Oleuropein-Aglycone (OA) exhibit anti-inflammatory and antioxidant effects.

They reduce inflammatory markers (IL-1β, TNF-α, IL-8, IL-6) in aging endothelial and airway epithelial cells and modulate SOD2, NF-kB, ACE2, and TMPRSS2 – factors related to respiratory viral infections.

OLE, OC, and OA show promise in controlling inflammation, particularly in respiratory infections and aging-related conditions [1].

Is there a way to enhance the benefits of olive leaf extract? Possibly—you can supplement with it. While individual experiences may vary, over 92% of users who have taken a supplement containing olive leaf extract (OLE) on Amazon have given it highly positive reviews.*

A user, Kindle Customer, found that the supplement helped improve energy levels and overall well-being. It is an effective option for those looking to supplement with natural antioxidants.*

May Reduce Risk of Diabetes

Olive Leaf Extract (OLE) has shown hypoglycemic effects in individuals with type 2 diabetes and in animal models. In a 14-week clinical trial, participants who took 500 mg of OLE daily experienced significant reductions in HbA1c and fasting plasma insulin.

In animal studies, OLE decreased starch digestion and absorption, indicating its potential in improving glucose regulation and serving as a complementary therapy for diabetes management [6]. However, animal studies can only tell us so much—human trials are needed to get the full picture.

A meta-analysis of 8 trials involving 162 diabetic mice revealed that OLE significantly increased insulin levels and decreased blood glucose, total cholesterol, and triglycerides. However, there was no significant weight difference between the OLE group and the placebo group.

These findings suggest that OLE benefits blood sugar control and lipid profile improvement in diabetic mice and may also be effective in humans [7].

May Improve Brain Health

Research suggests that Olive Leaf Extract may act as a “shield” protecting the brain from lead-induced damage due to its powerful antioxidant properties, which reduce neuronal damage and eliminate free radicals. This discovery opens new avenues for effective lead detoxification [8].

Furthermore, OLE has shown potential in protecting the brain from inflammation and memory decline caused by exposure to toluene and noise. It helps reduce oxidative stress, preserve brain structure, and improve learning abilities, suggesting its potential as a natural solution for manage neurotoxic effects [9].

May Manage Herpes

Herpes is one of the most common sexually transmitted infections (STIs). Due to acyclovir resistance, alternative treatments are needed. Olea Europaea and imiquimod have demonstrated antiviral and immune-boosting effects against HSV.

Olive Leaf Extract (OLE) has been effective against HSV-1 and is used in herpes treatment. In one study, OLE resolved lesions in 4 out of 6 patients within 48-72 hours and improved symptoms by 66% in the remaining 2 patients.

Oleuropein, a compound in OLE, exhibits anti-cancer, antibacterial, antiviral (including against rotavirus, hepatitis, influenza, herpes, and HIV), anti-inflammatory, and analgesic properties [10]. However, this study is small in scale and cannot replace standard antiviral drugs.

A study comparing the effectiveness of 2% Olive Leaf Extract (OLE) cream and 5% acyclovir cream in managing HSV-1 in 66 patients showed that both were effective. However, the OLE group experienced faster relief from bleeding, itching, pain, irritation, and discoloration.

The OLE group also had a shorter treatment duration (P = 0.001), suggesting that OLE cream may be more effective than acyclovir in managing HSV-1 outbreaks [11].

Other Benefits of Olive Leaf Extract

Impact on Physical Performance:

In a randomized crossover trial involving 15 young adults, Olive Leaf Extract did not significantly reduce performance compared to the control period.

However, another study on 9 healthy male athletes showed that oleuropein-rich extract increased tryptophan (a serotonin precursor) and acylcarnitines in serum and urine. These compounds may enhance endurance and reduce perceived exertion during exercise [3].

Effects on Thyroid Function:

Animal studies indicate that Olive Leaf Extract increases triiodothyronine (T3) and decreases thyroid-stimulating hormone (TSH), potentially through a feedback mechanism.

A systematic review of four animal studies also confirmed its thyroid-stimulating effects in healthy animals and its protective role under heat stress or chemical-induced hypothyroidism [3]. However, what works in animals doesn’t always translate to humans—more research is needed to be sure.

Olive Leaf Extract Side Effects

Potential Side Effects and Interactions [2]:

• Herxheimer Reaction: An immune response occurring when the body detoxifies from killed pathogens, which may cause headaches, joint pain, fever, nausea, sore throat, and dizziness (especially in people with low blood pressure). Drinking 4-6 glasses of water daily can help alleviate these symptoms.
• Stomach Irritation: May occur if the extract is too potent. Taking it with food can reduce irritation.
• Diarrhea: Possibly due to a Herxheimer reaction as the extract kills candida in the intestines.
• Acid Reflux: Often caused by peppermint-flavored extracts; using unflavored or diluted versions can help.

Interactions:

• Blood Pressure and Diabetes Medication: OLE may enhance the effects of antihypertensive and antidiabetic drugs.
• Anticoagulants: It may increase the effectiveness of blood thinners.
• Thyroid Conditions: Caution is advised for individuals with hyperthyroidism or goiter.

How To Take Olive Leaf Extract Safely

Before starting Olive Leaf Extract, especially if you are on medication, pregnant, breastfeeding, or have any health conditions, consult your healthcare provider to ensure safety.

Choosing the Right Form and Dosage:

Olive Leaf Extract is available as capsules, tablets, and liquid forms. The appropriate dosage depends on the product's concentration and your health needs. The recommended dose is 500 mg twice daily for 8 weeks. Follow the manufacturer’s instructions or your doctor's recommendations [3].

Tips for Safe Consumption:

Start with a Low Dose: Begin with a low dose to monitor your body’s response and gradually increase if needed.

Stay Hydrated: Drinking plenty of water helps minimize potential side effects such as headaches or digestive discomfort [12].

Monitor for Side Effects: Although generally safe, some people may experience mild side effects such as stomach discomfort, diarrhea, or headaches. If side effects persist or worsen, discontinue use and consult your healthcare provider [12].

How Much Olive Leaf Extract Per Day Should You Take?

The dosage of OLE depends on the intended use and individual health conditions [3]:

• For Stage 1 Hypertension: 500 mg twice daily for 8 weeks.
• To Support Insulin and Reduce Cardiovascular Risk: An equivalent dose of 51.1 mg oleuropein and 9.7 mg hydroxytyrosol daily for 12 weeks.
• Note: Liquid extracts are generally more easily absorbed than capsules or tablets. Consult a healthcare professional to determine the appropriate dosage for your health condition.

Olive Leaf Tea as an Alternative:

• Preparation: Steep about 2 teaspoons of dried olive leaves in 150-180 ml of boiling water for about 30
• minutes. Strain and enjoy.
• Dosage: Up to 4 times daily.
• Benefits: Olive leaf tea is rich in natural antioxidants and caffeine-free, making it a suitable option for those looking to relax without the stimulating effects of green tea or coffee.

Conclusion

Olive leaf extract is a beneficial option for cardiovascular health and  immunity. However, it should be used correctly to avoid unwanted side effects. Consult a healthcare provider before use and follow recommended dosages for the best results. If you find this article helpful, feel free to share it with others!