Olive Leaf Extract


Olive leaf extract refers to the molecules derived from the leaves of the olive plant. The olive fruit (what we consume) is what olive oil is made from and the olive leaf extract has different chemical compounds that alter physiology and neurochemistry.

The primary bioactive molecules in olive leaf extract are oleuropein and hydroxytyrosol, which are known to influence blood pressure [1], reduce cholesterol [2], and has neuroprotective and neurogenesis effects as well [3].

Also Known As

Olive polyphenols

Editors’ Thoughts on Olive Leaf Extract

It seems olive leaf extract might be a good remedy for people who are suffering from high blood pressure or cholesterol. While this doesn’t directly relate to the brain, I’m interested in the effects of nerve-growth factor (NGF) and BDNF, which are both neurogenesis agents that help grow new brain cells.

There are not many more cognitive effects of olive leaf extract and the side effects look kind of ugly from the few anecdotes I have read (though some people don’t have any bad experiences). I’m not sure I would personally risk it, but it could be a novel way of boosting both brain and body (especially for older people who have blood pressure or cholesterol issues).

Mansal Denton, Nootropedia Editor

olive leaf extract

Olive Leaf Extract Benefits

The benefits of olive leaf extract primarily revolve around improving the health of heart and cholesterol levels. In a 2013 PLoS One study, researchers concluded that olive leaf polyphenols for 12 weeks could improve insulin sensitivity, which is a key indicator for metabolic disease (diabetes) [4].

Another trial over a 2 – 4 week period showed that olive oil could reduce LDL and blood pressure alone [5]. That could be independent of the olive leaf, but another study confirmed the results using only the leaf extract [6].

Generally, most people who find olive leaf extract interesting as a supplement are looking at the benefits for heart disease. However, there are still benefits of olive leaf extract specifically with the intention of protecting neurological connections and even growing new neurons (neurogenesis).

In one study, researchers found that olive leaf extract could be neuroprotective because of strong antioxidant effects [7]. Some evidence suggests olive leaf extract works as a neuroprotective with similar mechanisms as rhodiola rosea. The antioxidant effects are powerful, but they may not be as strong as other natural nootropics like green tea extract, for example.

The final cognitive benefit of olive leaf extract is the influence on nerve-growth factor (NGF) and brain derived neurotrophic factor (BDNF). While olive leaf extract does reduce both NGF and BDNF in certain regions of the brain, it increases it in others [8]. The conclusion from the 2014 study in Natural Product Research thus seems to be inconclusive given the possible trade offs going on with these brain chemicals.

Olive Leaf Extract Side Effects

The side effects of olive leaf extract can be appetite suppression, headaches, sweating, and flu like symptoms. Some people have gastrointestinal distress as well.

The appetite suppression is supposedly different from most stimulants in that it feels genuinely uncomfortable (and in some cases is distracting). Other people experience irritability and anger when taking olive leaf extract.

The olive leaf extract side effects may depend on the administration method. For some people, taking pills can create side effects while other people have plenty of benefits. Surely, the side effects are not as worthwhile for a healthy individual with good blood pressure and cholesterol, but for those who do not, this might be a good trade off.

Olive Leaf Extract Dosage

The olive leaf extract dosage will be anywhere between 500 – 1000 mg per day. Typically, you also want to buy olive leaf extract that is standardized to the bioactive molecules. This might be something like 20% oleuropein and 30% hydroxytyrosol. Finding a product with an olive leaf extract dosage that fits in this manner is going to be best.

How and Where to Buy Olive Leaf Extract

The best way to buy olive leaf extract is to go online to make sure that you have the right dosage and standard bioactive ingredients. A local pharmacy or grocery store might have olive leaf extract for sale, but better to get it online where you can compile research.

The best brand that we found in capsule form is the Healths Harmony brand. They have a standardized product, it is non-GMO, and all of the other necessities to make sure you are getting the right product.

That being said, there are also sublingual (solutions in liquid form) options that work well for people online. Whichever olive leaf extract supplement that you buy, make sure you are clear why you are doing so. It is safe to find them online, but whether they are really worthwhile is another story.

Olive Leaf Extract Reviews

All of the olive leaf extract reviews that you will find online are personal anecdotes and should be taken in that context. While anecdotes are a great piece of data to identify what might work for you, they are not a 1 to 1 correlation with what you will experience.

The olive leaf extract reviews online have been generally pretty negative about the supplement, which may be something to consider before you buy. Take these reviews of olive leaf extract with a grain of salt, but also utilize them to make the right decision for you.

Selected Community Experiences

“I found it to be great for blood pressure lowering, however it had some strong side effects for me and thats why I stopped using it after approx 1.5-2weeks: First of all it has very very strong apetite supressing effects, I cannot point this out enough, this is very different from the stimulant like apetite supression effect. There is some food aversion somehow with OLE, and its not nice, which is not surprising since it has strong actions on gut hormones and neuropeptide Y what I remember from it a while ago. Second the ‘herxheimer' it can and did give me personally, headaches, sweating, flu like sypmtoms, enough to quit using it.” – Disturbed83 [9]

“I'm taking it for Lyme disease and blood pressure. Hydroxytyrosol can kill lyme spirochetes and cystic forms in vitro. Everytime I take it I get angry and irritable. Other brands also did this but this one is worse and supresses my apetite.” – birthdaysuit111 [10]

References (Click to Expand)
  1. //www.ncbi.nlm.nih.gov/pubmed/23516412
  2. //www.ncbi.nlm.nih.gov/pubmed/17617938
  3. //www.ncbi.nlm.nih.gov/pubmed/24865115
  4. //www.ncbi.nlm.nih.gov/pubmed/23516412
  5. //www.ncbi.nlm.nih.gov/pubmed/15939067
  6. //www.ncbi.nlm.nih.gov/pubmed/21036583
  7. //www.ncbi.nlm.nih.gov/pubmed/23394606
  8. //www.ncbi.nlm.nih.gov/pubmed/24865115
  9. //www.reddit.com/r/Nootropics/comments/6adxqw/olive_leaf_extract/
  10. Ibid.
Other Scientific Resources (Click to Expand)
  1. //sciencelinks.jp/j-east/article/200311/000020031103A0275319.php
  2. //www.ncbi.nlm.nih.gov/pubmed/21036583
  3. //www.ncbi.nlm.nih.gov/pubmed/12648829
  4. //kbd.kew.org/kbd/detailedresult.do?id=108406
  5. //www.ncbi.nlm.nih.gov/pubmed/21179340
  6. //pubs.rsc.org/en/Content/ArticleLanding/1995/P1/p19950001519
  7. //www.sciencedirect.com/science/article/pii/S0031942200950155
  8. //www.sciencedirect.com/science/article/pii/0031942289850095
  9. //www.ncbi.nlm.nih.gov/pubmed/23516412
  10. //www.ncbi.nlm.nih.gov/pubmed/23194770
  11. //www.ncbi.nlm.nih.gov/pubmed/18729245
  12. //connection.ebscohost.com/c/articles/39342378/phytochemical-analysis-gastroprotective-activity-olive-leaf-extract
  13. //www.itqb.unl.pt/labs/mass-spectrometry/phenolic-compounds-and-antioxidant-activity-in-olea-europaea-l.-fruits-and-leaves.pdf
  14. //www.ncbi.nlm.nih.gov/pubmed/20335636
  15. //www.ncbi.nlm.nih.gov/pubmed/23175023
  16. //www.ncbi.nlm.nih.gov/pubmed/23210780
  17. //www.ncbi.nlm.nih.gov/pubmed/22987739
  18. //openagricola.nal.usda.gov/Record/IND23251345
  19. //www.ncbi.nlm.nih.gov/pubmed/22691108
  20. //www.ncbi.nlm.nih.gov/pubmed/19906250
  21. //www.ncbi.nlm.nih.gov/pubmed/10794611
  22. //www.ncbi.nlm.nih.gov/pubmed/10519090
  23. //www.ncbi.nlm.nih.gov/pubmed/11087455
  24. //www.ncbi.nlm.nih.gov/pubmed/16608240
  25. //www.ncbi.nlm.nih.gov/pubmed/11714367
  26. //link.springer.com/article/10.1007%2Fs11746-000-0115-4?LI=true
  27. //www.sciencedirect.com/science/article/pii/S0889157507000853
  28. //www.ncbi.nlm.nih.gov/pubmed/10894841
  29. //www.ncbi.nlm.nih.gov/pubmed/16442552
  30. //pubs.acs.org/doi/abs/10.1021/jf00071a014


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