Olive Leaf Extract: Everything You Could Possibly Want To Know

olive leaf extract being cultivated for use in supplements

When you think “general health supplements”, Olive Leaf extract probably isn’t the first thing that comes to mind.

Still, millions of people throughout the world use this unique herbal supplement for a variety of reasons.

After all, we eat Olives.  We use Olive Oil when we cook.  Most people, if asked, would say Olives are “healthy”.

So, when you think about it, taking the health benefits of Olives and cramming them into a capsule or a liquid concentrate would be a logical next step…

In this article, we’re going to take a hard look at the scientific research behind Olive Leaf extract.  By the end of it, you’ll know exactly what it is, what the benefits are, and therefore, whether supplementing with it is a good idea.

So, if you’re ready to learn everything you could possible want to know about Olive Leaf extract, lets get to it…

What Is Olive Leaf Extract?

Olive Leaf Extract is derived from the leaves of Olea europaea, more commonly known as the Olive tree.  

This is the same plant that the Olives you put on your salad (or pizza) come from.  Olives are simply the fruit of Olea europaea. 

Olive Leaves

While the Olives themselves are processed into food products such as canned Olives and Olive Oil, the leaves serve a purpose as well.

Olive leaves are rich in phytonutrients which give them a variety of health benefits and medicinal uses.

This is why Olive leaves are prepared into an extract which can be either ethanol-based, water-based, or oil-based.  An ethanol-based Olive Leaf Extract would be a tincture (liquid).

The Olive Leaf extract that comes in the form of powder in capsules is a water-based extract that has been dehydrated.

Usually, Olive Leaf extract is standardized for certain chemical components which are believed to be responsible for the major health benefits.

Some of these benefits are just starting to come to light, but others have been known for thousands of years.

Olive Leaf History Of Use

olives, olive oil, and olive leaves layed out across table

Olea europaea (the Olive plant) is native to the Mediterranean region.  So, naturally, it has been used by the indigenous people of that area for centuries for a variety of different things.

They didn’t just use one part of the plant either, though.  The fruit (the actual Olives) AND the leaves were made into oils, and teas.  They were eaten and rubbed on the skin.

Some of the common uses were:

  • skin health
  • hairhealth
  • as a laxative
  • treating diabetes
  • reducing inflammation

The people of the Mediterranean (and anyone who traded with them) had many different ways of preparing Olives and Olive leaves, depending on the use case.

In the end, however, the active compounds that were actually responsible for the benefits were the same though.

This explains why some studies have found similar benefits using different forms of Olea europaeabased products, like Olive Oil or Olive Leaf extract.

Of course, these days we have the scientific sophistication to determine the chemical composition of Olive Leaves and this has allowed us to study, not only the entire plant, but its individual components as well.

The Active Components Of Olive Leaf Extract

scientist holding test tube with olive leaf in it

Since Olive Leaf Extract is derived from a plant (the Olive plant), it contains literally hundreds of distinct chemical components.

When we talk about the health benefits of Olive Leaf Extract supplements, however, two molecules in particular dominate the conversation:





the presence of phenolic compounds such as Oleuropein and Hydroxytyrosol is responsible for the unique, mildly bitter taste of Olives and Olive Oil.

These are also the two primary chemical components of Olive Leaf extract believed to be responsible for the majority of the health benefits.

There are of course other chemical compounds present in Olive Leaves, but you’ll almost always see Olive Leaf Extract supplements standardized for one or both of these key components.

Most extraction processes and production methods preserve both of these compounds, so you won’t find many Olive Leaf Extract supplements that only contain one or the other.  In other words, they stick together.

The important thing to takeaway from this is that when we talk about the health benefits of Olive Leaf Extract supplements, we’re talking mainly about Oleuropein and Hydroxytyrosol.

Now let’s talk about what those benefits are…

What Are The Proven Benefits Of Olive Leaf Extract?

Olives, Olive leaves, Olive Oil, and various kinds of Olive Leaf extracts have been used for centuries as a kind of “folk-medicine”, so it has it’s fair share of alleged claims attached to it.

Fortunately, modern science is starting to catch up and actually confirm (or deny) some of these benefits.  So, it’s not just folk-medicine anymore.

Research indicates Olive Leaf extract can be useful for a few things.

Olive Leaf Extract Improves Insulin Sensitivity/Blood Sugar

One of the key areas of interest with Olive Leaf Extract is how it can potentially impact things like Insulin Sensitivity, carbohydrate absorption, and help regulate blood sugar levels.

In vitro (not in a living organism, more like a test-tube), certain chemical components of Olive Leaf Extract have bee shown to inhibit the enzyme Amylase.

Amylase is one of the primary enzymes involved with absorbing Carbohydrates.  Blocking the action of Amylase is often the claim attached to weight-loss supplements and “carb-blockers”.

Unfortunately, there are plenty of supplements that have been shown to work in vitro and then turned out to not actually be that effective.

So let’s talk about how Olive Leaf Extract works in living things.

Well, Olive Leaf Extract has actually been shown to improve blood glucose stabilization in mice AND humans.

A 2013 study found that Olive Leaf Extract–standardized for Oleuropein and Hydroxytyrosol  of course–improved Insulin sensitivity and Pancreatic function in middle-aged adult men. The subjects in this study were overweight but they didn’t have Diabetes or anything.

A recent (2016) meta-analysis which analyzed the results of several rodent and human studies together concluded that Olive Leaf Extract is DEFINITELY effective in mice for improving aspects of Diabetes and may be effective in humans as well, based on what little (but still notable) evidence there is.

When it comes to improving Insulin Sensitivity and promoting healthy blood sugar levels, all the evidence suggests that Olive Leaf Extract is effective.  We just need more human studies is all!

Olive Leaf Extract Improves Skin Health

Perhaps the most popular “folk-medicinal” use of Olive leaves, Olive Oil, or Olive Leaf Extract is as a skin health agent.  It’s been used to treat skin-related diseases and even heal wounds and burns.

There’s also some preliminary research which suggests it Oleuropein can protect against UV-radiation.  This has bee noted again and again throughout the research.

While there isn’t a whole lot of human data upon which to draw conclusions, all the preliminary (rodent) research is pretty consistent with the already popular notion that Olive Leaves are good for the skin.

People have been using Olive Leaves and Olive Oil specifically for skin-related benefits for centuries.  It’s no secret.

So, even though we don’t usually like the idea of drawing conclusions based on mice studies, it’s not much of a stretch to say that Olive Leaf Extract is beneficial for skin health.

If you’re Italian, you’re Grandmother already knew that, but it’s nice to know that science supports it as well.

Although there aren’t a ton of studies assessing the effects of Olive Leaf Extract on skin health, the preliminary evidence suggests it is useful as a skin-health agent.  This is also one of the more widely believed traditional uses for Olives and Olive Oil, so it’s not much of a stretch.

What Are The Potential Benefits Of Olive Leaf Extract?

Throughout the research which has been conducted on Olive Leaf extract and its chemical components, some potential benefits have been discovered unintentionally.

This is simply because much of the research involved measuring indications of general health (i.e. blood pressure, hormone levels, etc.).

Since these things have yet to be studied directly, though, we’ll just call them potential benefits for now.

Olive Leaf Extract May Lower LDL (Bad) Cholesterol

Olive Oil and Olive-related products have long been believed to have cardiovascular benefits.  Fortunately, this is one of the areas studies have focused on specifically, so there’s actually a lot of research upon which to draw conclusions.

Regular consumption of Olive Oil, containing the usual chemical components, has been shown, in numerous studies, to lower LDL Cholesterol in humans.

Low-Density Lipoprotein (LDL) Cholesterol, is sometimes referred to as “Bad Cholesterol“.  High-Density Lipoprotein (HDL) Cholesterol is referred to as “good Cholesterol”.  We now know that not all Cholesterol is bad, but high levels of LDL Cholesterol for too long can lead to heart disease and/or a stroke.

By increasing LDL oxidation rates, regular consumption of Olive Oil can reduce Bad Cholesterol and improve heart health.

Unfortunately, Olive Leaf Extract supplementation has failed to show the same benefits as regular Olive Oil consumption.

The reason is unclear, but the obvious guess is that something is present in Olive Oil that gets destroyed in the extraction process.

This is one of the few instances where it looks like Olive Oil is superior to Olive Leaf Extract, despite them usually containing the same active compounds.  Olive Oil consumption can lower LDL, but we don’t know about Olive Leaf Extract.

Olive Leaf Extract May Promote Better Hormonal Health

In one study–the same study referenced above in which Olive Leaf Extract improved Insulin Sensitivity–the researchers also noted an increase in the activity of Growth Hormone binding proteins, IGFBP-1 and IGFBP-2.

There was no increase in actual Growth Hormone levels (IGF-1 and IGF-2), but increased binding activity could theoretically mimic the effects of increased Growth Hormone.

In mice, Oleuropein (the key component of Olive Leaf Extract) has been shown to increase Testosterone and Luteinizing Hormone while decreasing Corticosterone levels, but there is absolutely no human evidence at this time to corroborate these findings.

Obviously, there needs to be A LOT more research, but there is some potential for favorably impacting hormonal health here.

There’s some preliminary evidence that Olive Leaf Extract can have a beneficial impact on hormonal health, but there haven’t been any studies which specifically investigated this.  It’s just something that has come up in studies which focused on other areas.

Olive Leaf Extract May Lower Blood Pressure

A lot of the studies involving weight-loss, insulin sensitivity, and things like that have also measured the impact of Olive Leaf Extract on Blood Pressure.

In mice, there have instances where it decreased Blood Pressure.  A few studies have had similar results, but this effect hasn’t been entirely consistent.  In one study, there was no such decrease in blood pressure.

In humans, the results have been similarly mixed.

The same study discussed above which found improve Insulin Sensitivity also measured Blood Pressure and found no significant impact.

However, other studies have found some modest decreases in Blood Pressure.

It’s not entirely clear why Olive Leaf Extract helps some people with blood pressure while others receive no benefit.  It’s a safe bet though, like any supplement, it’s more likely to lower your blood pressure if you have high blood pressure initially.  This isn’t so much a reduction as a correction to the norm.

Here’s the thing though…

Whether or not Olive Leaf Extract can help manage Blood Pressure is pretty irrelevant because there are much more effective supplements for that anyway.  So, why spend time debating whether an 8% in one study outweighs the failure of another study.  Just use Grapeseed Extract instead.

The studies are mixed.  Some say Olive Leaf Extract lowers blood pressure.  Others say it doesn’t.

Is Olive Leaf Extract Effective For Weight-Loss?

Much of the research regarding Olive Leaf Extract has looked specifically at how it may influence weight-loss and/or fat-burning.

In fact, Oleuropein has become a relatively popular ingredient (usually found in the form of Olive Leaf Extract) in fat-burning supplements.

This is primarily due to preliminary research which indicates that Olive Leaf Extract increases levels of Adrenaline and Noradrenaline (fat-burning hormones) in mice.  It was concluded that Oleuropein was responsible for this alone.

Adrenaline and Noradrenaline are two neurotransmitters/hormones which belong to a group of chemicals produced in the body called Catecholamines.

Catecholamines, as a whole, promote fat-loss.  They directly stimulate the process of Lipolysis, or fat-breakdown.

Increasing levels of Catecholamines is a key target of just about every stimulant-based fat-burning supplement.

Okay, so Olive Leaf Extract is capable of increasing these fat-burning hormones.  Doesn’t that mean it burns fat?

Well…Not exactly.

Olive Leaf Extract has failed to promote weight-loss when studied in humans, more than once.  Olive Oil itself has been a similar failure when it comes to promoting weight-loss.

So what’s the deal?

Olive Leaf Extract increases Adrenaline and Noradrenaline, two fat-burning hormones, but still doesn’t burn fat?

How can that be?!

Well, the leading theory is that it has to do with other compounds in Olive Leaf (not necessarily Oleuropein) that down-regulate beta-receptors.

Beta-receptors are responsible for initiating lipolysis (fat-breakdown).

If Olive Leaf extract contains other compounds that block these receptors, that would negate the fat-burning effects of Oleuropein, despite it increasing levels of Catecholamines which would normally increase fat-burning.

If that’s too confusing to follow, don’t worry about it.  I’ll put it like this…

Although it has developed a bit of a reputation as a fat-burner and weight-loss supplement, there’s no evidence that Olive Leaf Extract is effective in this regard.  In fact, there’s only evidence to the contrary.

What’s The Clinically Effective Dosage Of Olive Leaf Extract?

Most of the studies involving Olive Leaf extract have used doses ranging from 500mg to 1000mg per day.

Most of these studies have had a duration of several weeks, but Olive Leaf extract is a general health supplement that should probably just be taken on an ongoing basis (basically forever).

The important thing though, isn’t so much how much Olive Leaf extract you’re taking, but how much of the active components you’re getting.

Remember, Oleuropein and Hydroxytyrosol are the active components that provide the benefits, so you want make sure you’re Olive Leaf Extract supplement provides a sufficient dose of those.

There are plenty of low-quality extracts out there that may not provide the benefits you’re looking for because they simply do not contain enough of the active components.

Not all supplements are created equal!

Choosing The Best Olive Leaf Extract Supplement

With any herbal supplement, quality is everything.  Olive Leaf Extract is no exception to that.  There are high quality extracts, with adequate levels of phenolic compounds, and there are low quality extracts, with inadequate levels.

On average, you’ll find Olive Leaf extract supplements that are standardized for anywhere from 6-20% Oleuropein.

The hydroxytyrosol concentration isn’t usually listed but, like we discussed earlier, these two molecules are found in virtually every preparation of Olives or Olive Leaves so, as long as you’re using a high quality extract, there’s bound to be some hydroxytyrosol in there as well.

Start with 500-1000mg of a 20% extract each day and see how it goes…

Does Olive Leaf Extract Have Any Side Effects?

Pretty high doses of Olive Leaf Extract (1000mg) have been well-tolerated and no study has reported any kind of obvious adverse reaction.

Given the prevalence of Olives and Olive-based foods in the Mediterranean-style diet, allergic reactions are rare.

Still, it’s possible to be allergic to anything.

As with any supplement, it’s recommended to discuss taking Olive Leaf Extract with your doctor before you actually start taking it.

As long as they get their info from the right places, they’re be able to tell you if there’s anything you should be worried about.

The Bottom Line On Olive Leaf Extract

Olive Leaf Extract is potentially pretty useful as a supplement if you want to do things like:

  • enhance insulin sensitivity
  • lower LDL (‘bad’ cholesterol)
  • improve skin health

and it may have some additional benefits as well.

Contrary to popular belief, it’s not really an effective fat-loss supplement, despite being present in many of them and often advertised as such.

As with many herbal supplements, science is still catching up with the traditional uses of Olive leaves and Olive Leaf extract.  So far, it looks like the ancient Mediterranean people were definitely on to something though!

Have anything to share about olive leaf extract?  Comment below…

I’m Matt Theis, founder of SuppWithThat, Momentum Nutrition, and Singular Sport. I created SWT to separate the science from the hype and publish accurate, research-based information on supplements. If you like what I have to say here, feel free to check out my supplements at and

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