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5 Best Olive Leaf Extracts That Pack 2x the Antioxidants of Green Tea
Written By Natalie Wilkinson
Olive oil gets all the attention—but it’s the leaf that holds the secret compound: a bitter plant substance called oleuropein. It’s up to 2x stronger than green tea extract. And it’s what gives the olive tree its resistance to disease. When concentrated into an extract, it delivers those protective benefits to you.
Oleuropein converts to hydroxytyrosol—an antioxidant stronger than vitamin C, green tea extract, and even curcumin (from turmeric)
Feeling weighed down by high cholesterol or blood pressure? Struggling with endless colds or stuck in a cycle of fatigue and low energy?
Studies show olive leaf extract can lower LDL cholesterol and reduce hypertension. Many olive leaf extract users are in the ‘my doctor says I’m borderline high cholesterol’ or ‘borderline high blood pressure’ phase. And they want a natural option instead of committing to statins or lifelong hypertension medications. Likewise, if you’re the one who gets sick every time someone sneezes at work, the best olive leaf extract can fortify your immune system and help you recover quicker. That said, our review team voted the Island Nutrition olive leaf extract best overall due to its high oleuropein content and authentic sourcing from family-run farms in Spain.
5 Best Olive Leaf Extracts of 2025
Island Nutrition Olive Leaf Extract
Best Overall
When choosing an olive leaf extract, believe what other people have said. The Island Nutrition olive leaf extract’s 4.6-star rating tells you something: it’s high quality, well-crafted, and delivers on its promises. In the reviews, you’ll see words like “felt the difference,” “five stars,” and “worth every penny.” It doesn’t just meet the standard—it raises it.
Beyond the high ratings, this extract is processed using a chemical-free method that preserves the full spectrum of polyphenols (powerful antioxidants). It contains 25% oleuropein, 40% total polyphenols, and a 20% hydroxytyrosol complex. But what does that actually mean? It means each capsule has a concentrated dose of the most researched compounds found in olive leaves and olive oil. Oleuropein boosts immunity, while hydroxytyrosol works as a strong antioxidant to reduce cell damage. Together, they help protect the body at a cellular level. With that in mind, this brand is one of the highest-rated olive leaf extracts online—with more than 1,000 five-star reviews and a loyal customer base that keeps coming back.
Carlyle Olive Leaf Extract
Runner-Up
The Carlyle olive leaf extract offers a different kind of value—high potency and a much lower price. Each capsule contains the equivalent of 9,000mg of olive leaf and 150mg of standardized oleuropein. That’s a higher dose of oleuropein than the best overall, though it’s not quite as concentrated in terms of total polyphenols. Even so, it’s an impressive formula, especially when you consider the cost: just $0.07 per capsule.
For the price difference—$39 vs. $8—you’re paying for a more complete profile in Island Nutrition’s extract. It’s a matter of what you value more: high-volume extract (Carlyle) or targeted, standardized polyphenols (Island Nutrition). That said, the runner-up is still laboratory-tested, non-GMO, and made by a trusted U.S. brand with decades of experience. So if you’re looking for an affordable way to get the benefits of olive leaf extract, this is the one to pick.
Now Foods Olive Leaf Extract
Best Value
The supplement everyone’s talking about on TikTok? That’s this supplement. The Now Foods olive leaf extract holds a 4.6-star rating from over 5,000 customers and sold more than 2,000 bottles in the past month. It’s not the most concentrated formula on this list, but it remains a popular choice for those who want a lower-dose olive leaf supplement from a long-established, GMP-certified brand. Ingredient-wise, each capsule contains 500mg of olive leaf extract standardized to 6% oleuropein, with 120 capsules per bottle—making it the bottle that will last you the longest.
While it doesn’t match the potency of the best overall (25% oleuropein with added hydroxytyrosol) or the runner-up (150mg standardized oleuropein), it offers a formula made by a brand trusted since 1968. For those seeking a lower-intensity extract backed by decades of manufacturing experience, this is a reliable pick.
Pure Encapsulations Olive Leaf Extract
Hypoallergenic Pick
If you’re looking for a supplement that’s hypoallergenic and ultra-clean, the Pure Encapsulations olive leaf extract is the clear standout. It’s made by one of the most respected names in practitioner-grade supplements and is free from common allergens, artificial fillers, and unnecessary additives. While the label mentions 15% oleuropein, the focus here is more on purity and formulation—developed with input from medical professionals and tested for quality at every stage.
That said, it’s more expensive than both the best overall and the runner-up. A 60-capsule bottle is priced around $40 (as of this writing), which means you’re paying more for premium sourcing and hypoallergenic assurance rather than high-dose potency. For those with dietary sensitivities or looking for the most strictly vetted supplement, this is the supplement most often recommended by professionals.
Best Naturals Olive Leaf Extract
Best Range
All the supplements on our list have a 4.5 or 4.6-star rating—and the Best Naturals olive leaf extract is no exception. Each capsule contains 700mg of olive leaf extract, and the 90-count bottle is typically priced under $10. Beyond that, it’s third-party lab tested, made in a GMP-compliant, FDA-registered facility, and free from gluten, artificial additives, preservatives, and common allergens.
Unlike the best overall from Island Nutrition that offers 25% oleuropein, this one contains 6% oleuropein. Even so, for shoppers focused on clean ingredients and general antioxidant support—without paying a premium price—this is a solid and affordable choice.
Choosing the Best Olive Leaf Extract: A User’s Guide
13 Quick Facts About Olive Leaf Extract You’ll Want to Know
- Antioxidant strength: Oleuropein is up to 2x stronger than green tea extract.
- Sick less often: Reduced illness duration by 28% in athletes.
- Natural blood pressure support: Lowered systolic BP by 11.5 mmHg and diastolic by 4.8 mmHg in adults with stage 1 hypertension.
- As effective as medication: Matched Captopril’s effect on lowering blood pressure.
- Insulin sensitivity: Improved by 15%, with a 28% boost in β-cell function.
- Lowers LDL cholesterol: Reduced bad cholesterol levels in adults with mild hypertension.
- Antiviral: Shown to fight herpes, influenza A, and RSV in lab studies.
- Antibacterial: Inhibited growth of E. coli, Staphylococcus aureus, and Salmonella.
- Anti-fungal: Active against Candida albicans.
- Fights inflammation: Suppresses IL-6, TNF-α, and other pro-inflammatory markers.
- Skin benefits: Protects against UV damage and collagen breakdown in cell studies.
- Cognitive support: Shown to reduce oxidative stress in brain cells.
- Anticancer potential: In vitro studies show inhibition of breast, prostate, and bladder cancer cells.
7 Things You Need to Consider When Choosing an Olive Leaf Extract
1. Oleuropein Content
This is the compound everyone talks about—and for good reason. Oleuropein is the primary active polyphenol in olive leaves, and it’s been linked to immune support, antioxidant activity, and healthy blood sugar levels.
Some supplements list the olive leaf dose (like 500mg), but not how much of that is standardized to oleuropein. That matters. The Island Nutrition olive leaf extract, for example, contains 25% oleuropein per capsule—a high and clearly labeled amount that helps you know exactly what you’re getting.
2. Total Polyphenols
Oleuropein is important, but it’s not the only polyphenol in olive leaves. That said, look for extracts that mention total polyphenols on the label. These compounds work together to support the body at a deeper level. Some supplements leave this off entirely. The better ones include a full spectrum. The Island Nutrition olive leaf extract includes 40% total polyphenols, which makes a big difference in long-term antioxidant support.
3. Hydroxytyrosol Content
This is one of the most potent antioxidants in olive oil—often more powerful than vitamin C—and it’s sometimes included in olive leaf formulas as part of a complex. If you see it on the label, that’s a good sign. A 20% hydroxytyrosol complex, like what’s found in the Island Nutrition olive leaf extract, gives you stronger immune protection and cellular health.
4. Standardization and Transparency
Don’t settle for vague descriptions like “pure,” “premium,” or “high quality.” Look for numbers: standardized percentages of oleuropein or hydroxytyrosol, third-party testing, and clear sourcing. Ultimately, if a label only mentions milligrams without any active compounds, it’s hard to know what you’re actually getting.
5. Country of Origin
Where the olive leaves are grown matters. Spain, Italy, and Greece are known for high-quality olives and strict farming practices. Many trusted products will clearly state the origin. Some will only say “made in the USA”—which doesn’t always mean the ingredients were grown there.
6. Processing Method
How the extract is made affects what ends up in the capsule. Traditional water and alcohol extractions preserve the polyphenols. And harsh solvents and high heat can destroy them.
7. Allergen and Filler Warnings
Last but not least—what’s not in your supplement matters just as much. Look for options free from gluten, GMOs, artificial preservatives, and unnecessary fillers. If you have allergies or sensitivities, choose a product that’s clearly labeled as hypoallergenic or free from common triggers.
Best Olive Leaf Extract FAQs
What is olive leaf extract?
Olive leaf extract is made from the leaves of the olive tree and contains natural compounds like oleuropein and hydroxytyrosol—known for their antioxidant and immune-supporting properties. It's been used for centuries in traditional Mediterranean wellness practices.
Can I take olive leaf extract if I am on medication?
It depends on the medication. Olive leaf extract may affect blood pressure or blood sugar levels, so it’s best to check with your doctor before starting—especially if you're taking meds for those conditions.
How long does it take for olive leaf extract to work?
With the Island Nutrition olive leaf extract, people notice changes in energy or immune resilience within a few days, but deeper benefits—like antioxidant protection or blood sugar support—tend to build over several weeks. That said, a high-quality product will deliver results more consistently thanks to its standardized active compounds.
Can I take olive leaf extract during pregnancy?
Pregnant or breastfeeding women should avoid olive leaf extract unless advised by a healthcare provider. There isn’t enough clinical research to confirm its safety during pregnancy.
Why did the Island Nutrition olive leaf extract rank best overall?
It has 25% oleuropein, 40% total polyphenols, and a 20% hydroxytyrosol complex. It’s also sourced from olive trees grown in Spain and processed using traditional, chemical-free methods. If you’re looking for a supplement with transparency, strength, and clean sourcing, the Island Nutrition olive leaf extract checks every box.
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