Not for nothing was the olive wreath bestowed on winners of the Olympic games in ancient Greece. The leaves have been used traditionally in the areas where olive trees grew abundantly to treat varied ailments like fever, asthma, high blood pressure, diabetes, eye infections, diarrhea, hemorrhoids, and gout.1 And with the renewed interest in alternative medicine worldwide, olive leaves are now making a comeback. Modern research finds that the health benefits of the leaves are chiefly due to two compounds called oleuropein and its metabolite hydroxytyrosol, among other bioactive compounds called secoiridoids and flavonoids.
While the olive fruit and the extra-virgin oil pressed from the fruit also have the same polyphenols, which are a group of plant chemicals with antioxidative capacity, the leaves have more variety and quantity. The polyphenols in the leaves may also have different structure, which may result in different health benefits.2
Since the leaves are too bitter thanks to the presence of oleuropein, olive leaf extract (OLE) is sold in capsule form as supplement. The supplement typically contains some of these polyphenols, including oleuropein and hydroxytyrosol, in a standardized amount.3 Before you start taking them, here’s a look at the benefits of olive leaf extract and precautions you may need to take.
1. Reduces High Blood Pressure
Olive leaves can prevent a hike in blood pressure as well as lower chronically high blood pressure without any side effects. A study on patients with high blood pressure showed that taking olive leave extract reduced the blood pressure, as well as glucose levels, significantly in 3 months. Another study found it to be as effective as captopril, a standard antihypertensive drug. Olive leaf extract was also found to lower the level of triglycerides. How does it work? The polyphenols in OLE relax the blood vessels by increasing the production of nitric oxide and fight oxidative damage to the arteries.4 5 6 7
2. Prevents Atherosclerosis And Cardiovascular Diseases
Atherosclerosis, or the hardening and blockage of arteries due to deposition of oxidized LDL cholesterol, is a major risk factor for heart diseases. While olive leaf polyphenols like oleuropein and hydroxytyrosol do not change the lipid levels in the body significantly, they prevent the oxidation of LDLs and act against the inflammatory response mounted by the body. So olive leaf extract helps avert atherosclerosis even when taken in small doses.8 9
3. Manages Diabetes
Olive leaf extract can be an effective weapon in your fight against diabetes. Even a handful of olives will help. OLE reduces blood sugar levels in various ways. A study on type 2 diabetes patients found that OLE significantly reduced the HbA1c values – these indicate how stable your blood glucose levels have been over the last 3 months). Researchers suggest that this could happen in two possible ways: a) OLE polyphenols improve insulin sensitivity and glucose uptake by the cells, thereby reducing blood glucose levels, or b) they inhibit the digestion and absorption of carbs.10
You could benefit from the anti-inflammatory benefits of olive leaf extracts even if you aren’t yet diabetic. In a small study on middle-aged overweight individuals at risk of developing metabolic syndrome, OLE could increase the insulin sensitivity by 15% more than the placebo could. The beta cells in the pancreas that are responsible for secreting insulin also showed a 28% increase in response.11
4. May Prevent Alzheimer’s And Parkinson’s
Olive leaf extract can protect nerves from oxidative damage and also enhance nerve growth in some parts of the brain. While human trials have not been conducted yet, an animal study shows that oleuropein in olives reduces and even prevents the buildup of beta-amyloid protein plaques and tau clumps in the brain – these two types of protein clumps end up killing nerve cells and leading to Alzheimer’s disease.12 13 Currently, further research on the effect of olive fruits and leaf on Alzheimer’s is underway at the Charles Sturt University in Australia.14
Olive leaves seem to have ability to fight Parkinson’s disease as well. Several cellular and animal studies have shown that the antioxidants, chiefly oleuropein, in olive leaves can fight oxidative damage and prevent the death of dopamine-producing nerve cells, a characteristic of Parkinson’s.15 16 But as with Alzheimer’s, no human trial has been conducted yet. Till then, it won’t hurt to have olive fruits and extra-virgin olive oil for this neuroprotective benefit and others.
5. Treats Arthritis
Traditional medicines have used olive leaves in treating gout. This may be attributed to olueropein, which curbs the enzyme that promotes the build-up of uric acid that cures the condition.17 18 And it has similar benefits for other forms of arthritis, which are in essence inflammatory disorders. Olive leaf extract protects the joints, enhances cartilage repair, and reduces pain and swelling as seen in an animal study.19 A human study has shown that taking dry olive leaf extract along with methotrexate can lower oxidative damage in cells, DNA damage, and inflammation in early-stage rheumatoid arthritis patients, but not in long-term patients whose damage might be too far gone.20
6. Fights Infections
Olive trees live for hundreds of years, and this might be due to the antimicrobial properties of olive polyphenols. The leaf extract was seen to kill several types of bacteria that cause intestinal infections, including Escherichia coli, and Candida albicans, a fungus.21 22 Olive leaves have shown antiviral effects in a number of studies on infected cells, including on HIV-1. In an in vitro study, it inhibited acute infection and cell to cell transmission of the infection. This needs to be further studied to understand if OLE could be used in the treatment for the hitherto incurable HIV infection.23
Olive leaf extract might also be the answer to your niggling common cold problem. In one animal study, a compound isolated from olive leaves could suppress a parainfluenza-3 viral infection when administered within minutes or 8 hours of infection.24 While human studies are lacking, if you trust the testimonials by users, it might be worth a try since it has no side effect.
7. May Prevent Cancer
Since olive leaves are so rich in bioactive antioxidants, it stands to reason that they have the capacity to prevent and treat cancer, which essentially starts with inflammation. Studies with OLE have shown that its antioxidants prevent DNA damage and thereby the formation of malignant cells, thus playing a chemopreventive role. On the other hand, the antioxidants can even induce programmed cell death (apoptosis) in tumor cells without affecting normal cells, thus showing potential in therapy. Oleuropein, in particular, prevents the growth, replication, and spread (metastasis) of cancer cells as well as the growth of new blood vessels that feed the cancer cells.25 26 27 28
However, while studies on isolated cells and animals have shown that olive leaf polyphenols can fight breast, prostate, colon, skin, and some forms of blood cancer, no clinical trial on humans exists till date. So it’s difficult to claim that olive leaf extract can prevent and treat cancers. That said, it can be taken alongside chemotherapy under the guidance of a doctor to reduce the side effects of chemo.29 30
8. Protects The Skin
Traditionally, different forms of olives have been used as skin cleansers and as a balm for wounds, and this isn’t without any basis. Studies show that olive leaves are effective in healing wounds, especially inflammatory ones. When animals with wounds were treated with a water extract of olive leaves, the excision wounds contracted by 87% and the tensile strength (a marker of wound healing) of incision wounds increased to 34.8% compared to other groups. Olive leaf extract was even more potent than a standard wound-healing ointment.31 32
Olive leaves can also prevent DNA damage in the skin caused by UV radiation and prevent the growth of tumors by reducing the levels of certain enzymes. This is why you may find a number of skincare products containing olive leaf extracts.33 34 These skin benefits are due to the presence of oleuropein and hydroxytyrosol, which also fight free radicals and protect the skin from premature aging.35
How To Use Olive Leaves
1. Olive Leaf Extract As A Powder And Tincture
While you can crush fresh leaves and make a powder, buying powders that are made using OLEs might be more effective for treating any health issues. The powder can be used in multiple ways:
If you don’t want to consume olive leaf extract capsules or powder, make a cup of tea by boiling a handful of fresh dried leaves. Make sure the leaves are pesticide-free and be warned that the taste is very bitter.
- Experiment by sprinkling on foods.
- Use it to make juices or smoothies.
- Use it to make a herbal tea.
- Have it as is or with a little bit of honey.
- Use it in face packs.
A typical dose is 500–1000 mg of the extract a day. It has no side effects but it’s best to consult your doctor on condition-specific dosage.
2. Olive Leaf Spray
Modern medicines use olive leaf spray to relieve respiratory issues like blocked nose, breathing difficulties, and sinus issues. The spray is used depending on the severity of the condition, so consult your doctor for the dosage.
A Word Of Caution
While olive leaf extract has no known side effects, avoid using olive leaves in high quantities if your blood pressure is naturally low, as it may cause dizziness due to further lowering of blood pressure. Also exercise caution if you are on blood thinners or on medication for high blood pressure and diabetes. Extremely high or strong doses of olive leaf extract can cause stomach upset or diarrhea. Start off with small doses and see how it works for you. If you’re pregnant or lactating, make sure you consult your doctor before trying olive leaves in any form or quantity.
|↑1, ↑31||Hashmi, Muhammad Ali, Afsar Khan, Muhammad Hanif, Umar Farooq, and Shagufta Perveen. “Traditional uses, phytochemistry, and pharmacology of Olea europaea (olive).” Evidence-Based Complementary and Alternative Medicine 2015 (2015).|
|↑2, ↑29||Boss, Anna, Karen S. Bishop, Gareth Marlow, Matthew PG Barnett, and Lynnette R. Ferguson. “Evidence to support the anti-cancer effect of olive leaf extract and future directions.” Nutrients 8, no. 8 (2016): 513.|
|↑3||Rahmanian, Neda, Seid Mahdi Jafari, and Touseef Ahmed Wani. “Bioactive profile, dehydration, extraction and application of the bioactive components of olive leaves.” Trends in Food Science & Technology 42, no. 2 (2015): 150-172.|
|↑4||Cherif, S., N. Rahal, M. Haouala, B. Hizaoui, F. Dargouth, M. Gueddiche, Z. Kallel, G. Balansard, and K. Boukef. “A clinical trial of a titrated Olea extract in the treatment of essential arterial hypertension.” Journal de pharmacie de Belgique 51, no. 2 (1995): 69-71.|
|↑5||Susalit, Endang, Nafrialdi Agus, Imam Effendi, Raymond R. Tjandrawinata, Dwi Nofiarny, Tania Perrinjaquet-Moccetti, and Marian Verbruggen. “Olive (Olea europaea) leaf extract effective in patients with stage-1 hypertension: comparison with Captopril.” Phytomedicine 18, no. 4 (2011): 251-258.|
|↑6||Khayyal, Mohamed T., Mona A. El-Ghazaly, Dalai M. Abdallah, Noha N. Nassar, Samuel N. Okpanyi, and Matthias-Heinrich Kreuter. “Blood pressure lowering effect of an olive leaf extract (Olea europaea) in L-NAME induced hypertension in rats.” Arzneimittel Forschung 52, no. 11 (2002): 797-802.|
|↑7||Visioli, Francesco, Stefano Bellosta, and Claudio Galli. “Oleuropein, the bitter principle of olives, enhances nitric oxide production by mouse macrophages.” Life sciences 62, no. 6 (1998): 541-546.|
|↑8||Singh, Indu, Michelle Mok, Anne-Marie Christensen, Alan H. Turner, and John A. Hawley. “The effects of polyphenols in olive leaves on platelet function.” Nutrition, metabolism and cardiovascular diseases 18, no. 2 (2008): 127-132.|
|↑9||Wang, Lihui, Chengyan Geng, Liping Jiang, Dezheng Gong, Dayu Liu, Hiroyuki Yoshimura, and Laifu Zhong. “The anti-atherosclerotic effect of olive leaf extract is related to suppressed inflammatory response in rabbits with experimental atherosclerosis.” European journal of nutrition 47, no. 5 (2008): 235-243.|
|↑10||Wainstein, Julio, Tali Ganz, Mona Boaz, Yosefa Bar Dayan, Eran Dolev, Zohar Kerem, and Zecharia Madar. “Olive leaf extract as a hypoglycemic agent in both human diabetic subjects and in rats.” Journal of medicinal food 15, no. 7 (2012): 605-610.|
|↑11||de Bock, Martin, Jose GB Derraik, Christine M. Brennan, Janene B. Biggs, Philip E. Morgan, Steven C. Hodgkinson, Paul L. Hofman, and Wayne S. Cutfield. “Olive (Olea europaea L.) leaf polyphenols improve insulin sensitivity in middle-aged overweight men: a randomized, placebo-controlled, crossover trial.” PloS one 8, no. 3 (2013): e57622.|
|↑12||Bazoti, Fotini N., Jonas Bergquist, Karin E. Markides, and Anthony Tsarbopoulos. “Noncovalent interaction between amyloid-β-peptide (1-40) and oleuropein studied by electrospray ionization mass spectrometry.” Journal of the American Society for Mass Spectrometry 17, no. 4 (2006): 568-575.|
|↑13, ↑28||Barbaro, Barbara, Gabriele Toietta, Roberta Maggio, Mario Arciello, Mirko Tarocchi, Andrea Galli, and Clara Balsano. “Effects of the olive-derived polyphenol oleuropein on human health.” International journal of molecular sciences 15, no. 10 (2014): 18508-18524.|
|↑14||Olives and the Alzheimer’s brain. Charles Sturt University.|
|↑15||Sarbishegi, Maryam, Enam Alhagh Charkhat Gorgich, Ozra Khajavi, Gholamreza Komeili, and Saeedeh Salimi. “The neuroprotective effects of hydro-alcoholic extract of olive (Olea europaea L.) leaf on rotenone-induced Parkinson’s disease in rat.” Metabolic brain disease 33, no. 1 (2018): 79-88.|
|↑16||Pasban-Aliabadi, Hamzeh, Saeed Esmaeili-Mahani, Vahid Sheibani, Mehdi Abbasnejad, Anahita Mehdizadeh, and Mohammad Mehdi Yaghoobi. “Inhibition of 6-hydroxydopamine-induced PC12 cell apoptosis by olive (Olea europaea L.) leaf extract is performed by its main component oleuropein.” Rejuvenation research 16, no. 2 (2013): 134-142.|
|↑17||Flemmig J, Kuchta K, Arnhold J, Rauwald HW. Olea europaea leaf (Ph.Eur.) extract as well as several of its isolated phenolics inhibit the gout-related enzyme xanthine oxidase. Phytomedicine.2011 May 15;18(7):561-6.|
|↑18||Impellizzeri, Daniela, Emanuela Esposito, Emanuela Mazzon, Irene Paterniti, Rosanna Di Paola, Valeria Maria Morittu, Antonio Procopio, Domenico Britti, and Salvatore Cuzzocrea. “Oleuropein aglycone, an olive oil compound, ameliorates development of arthritis caused by injection of collagen type II in mice.” Journal of Pharmacology and Experimental Therapeutics 339, no. 3 (2011): 859-869.|
|↑19||Gong, Dezheng, Chengyan Geng, Liping Jiang, Lihui Wang, Hiroyuki Yoshimura, and Laifu Zhong. “Mechanisms of Olive Leaf Extract‐Ameliorated Rat Arthritis Caused by Kaolin and Carrageenan.” Phytotherapy Research 26, no. 3 (2012): 397-402.|
|↑20||Čabarkapa, Andrea, Lada Živković, Sunčica Borozan, Mirjana Zlatković‐Švenda, Dragana Dekanski, Ivan Jančić, Marija Radak‐Perović, Vladan Bajić, and Biljana Spremo‐Potparević. “Dry Olive Leaf Extract in Combination with Methotrexate Reduces Cell Damage in Early Rheumatoid Arthritis Patients—A Pilot Study.” Phytotherapy Research 30, no. 10 (2016): 1615-1623.|
|↑21||Pereira, Ana Paula, Isabel CFR Ferreira, Filipa Marcelino, Patricia Valentão, Paula B. Andrade, Rosa Seabra, Leticia Estevinho, Albino Bento, and José Alberto Pereira. “Phenolic compounds and antimicrobial activity of olive (Olea europaea L. Cv. Cobrançosa) leaves.” Molecules 12, no. 5 (2007): 1153-1162.|
|↑22||Micol, Vicente, Nuria Caturla, Laura Pérez-Fons, Vicente Más, Luis Pérez, and Amparo Estepa. “The olive leaf extract exhibits antiviral activity against viral haemorrhagic septicaemia rhabdovirus (VHSV).” Antiviral research 66, no. 2 (2005): 129-136.|
|↑23||Lee-Huang, Sylvia, Li Zhang, Philip Lin Huang, Young-Tae Chang, and Paul L. Huang. “Anti-HIV activity of olive leaf extract (OLE) and modulation of host cell gene expression by HIV-1 infection and OLE treatment.” Biochemical and Biophysical Research Communications 307, no. 4 (2003): 1029-1037.|
|↑24||Soret, M. G. “Antiviral activity of calcium elenolate on parainfluenza infection of hamsters.” Antiviral activity of calcium elenolate on parainfluenza infection of hamsters. (1970).|
|↑25||Türkez, Hasan, and Başak Toğar. “Olive (Olea europaea L.) leaf extract counteracts genotoxicity and oxidative stress of permethrin in human lymphocytes.” The Journal of toxicological sciences 36, no. 5 (2011): 531-537.|
|↑26||Anter, Jaouad, Zahira Fernández-Bedmar, Myriam Villatoro-Pulido, Sebastian Demyda-Peyras, Miguel Moreno-Millán, Ángeles Alonso-Moraga, Andrés Muñoz-Serrano, and María Dolores Luque de Castro. “A pilot study on the DNA-protective, cytotoxic, and apoptosis-inducing properties of olive-leaf extracts.” Mutation Research/Genetic Toxicology and Environmental Mutagenesis 723, no. 2 (2011): 165-170.|
|↑27||Hamdi, Hamdi K., and Raquel Castellon. “Oleuropein, a non-toxic olive iridoid, is an anti-tumor agent and cytoskeleton disruptor.” Biochemical and biophysical research communications 334, no. 3 (2005): 769-778.|
|↑30||Ahmed, Khadija Muhamed. “The effect of olive leaf extract in decreasing the expression of two pro-inflammatory cytokines in patients receiving chemotherapy for cancer. A randomized clinical trial.” The Saudi dental journal 25, no. 4 (2013): 141-147.|
|↑32||Koca, Ufuk, Ipek Süntar, Esra Küpeli Akkol, Demet Yılmazer, and Murat Alper. “Wound repair potential of Olea europaea L. leaf extracts revealed by in vivo experimental models and comparative evaluation of the extracts’ antioxidant activity.” Journal of medicinal food 14, no. 1-2 (2011): 140-146.|
|↑33||Czerwińska, Monika E., Katarzyna Duszak, Andrzej Parzonko, and Anna K. Kiss. “Chemical composition and UVA-protecting activity of extracts from Ligustrum vulgare and Olea europaea Leaves.” Acta Biologica Cracoviensia s. Botanica 58, no. 2 (2016): 45-55.|
|↑34||Kimura, Yoshiyuki, and Maho Sumiyoshi. “Olive leaf extract and its main component oleuropein prevent chronic ultraviolet B radiation-induced skin damage and carcinogenesis in hairless mice.” The journal of nutrition 139, no. 11 (2009): 2079-2086.|
|↑35||Omar, Syed Haris. “Oleuropein in olive and its pharmacological effects.” Scientia pharmaceutica 78, no. 2 (2010): 133-154.|