We all know that olive oil is excellent for health. Oleuropein, one of the primary polyphenols present in it is what gives olive oil its many therapeutic properties. Interestingly, the leaves of the olive plant contain much higher concentrations of oleuropein than the olives from which the oil is derived. The bioactive compounds of olive leaf provide antioxidant, anti-inflammatory, antihypertensive and hypoglycemic properties. Read on to learn about olive leaf extract and their many health benefits.
What is olive leaf extract?
Olive leaf extract is taken from the leaves of the olive tree (Olea europaea). The olive tree ranges in height from 3 to 12 meters and has many branches. Its leaves are leathery and lance-shaped. They are dark green from above and silvery on the underside.
Olive leaf extract contains several chemical compounds like oleuropein and hydroxytyrosol and polyphenols and flavonoids including luteolin, rutin, caffeic acid, catechin, and apigenin. The composition of olive leaf extract can vary according to the plant variety, harvesting season, methods of leaf maturity, storage conditions, and extraction method.
History of olive leaf extract
According to Greek mythology, goddess Athena’s gifted the Olive tree to humanity. Olive leaf extract was used in the Mediterranean folk medicine since the times of the ancient Greeks, Romans, and Egyptians. Olive leaves compressions and infusions were used to treat pain, fever, infections, anxiety, and high blood pressure.
During the 1800s olive leaf extracts began to be used for the treatment of malaria. In the 1900s, scientists isolated oleuropein from olive leaves. They also discovered that oleuropein could stimulate circulation, lower blood pressure and cholesterol levels, prevent the growth of parasites, fungi, and harmful bacteria.
Benefits of olive leaf extracts
1. Improves heart health
According to research olive leaf extract can prevent atherosclerosis, which is known to increase the risk of heart disease. During a 2015 study, rats with high cholesterol levels were given 50 or 100 mg per kg per day of olive leaf extract. The results showed that both doses of olive leaf extract significantly decreased cholesterol levels (1). Dietary polyphenols in olive leaves help to prevent the formation of arterial plaques related to heart attacks and strokes (2).
2. Fights diabetes
Olive leaf extracts can reduce the risk of developing type 2 diabetes. These extracts lower blood sugar levels in the body. The polyphenols in olive leaf extracts play a vital role in delaying the production of blood sugar. During one study in New Zealand, 46 overweight participants took either olive leaf extract or a placebo for 12 weeks.
The results showed that the group that took olive leaf extracts has significant improvements in insulin sensitivity and pancreatic responsiveness (3). Another study found that the polyphenols found in olive leaf extract could induce improvements in blood glucose in prediabetes (4).
3. Reduce cancer risk
Olive leaf extracts contain a high quantity and variety of polyphenols which play an essential protective role in cancer and other inflammation-related diseases. Olive leaf polyphenols are anti-inflammatory, and they protect against DNA damage caused by free radicals.
Olive leaves contain oleuropein, which has an antioxidant and anti-angiogenic effect as it inhibits the reproduction and migration of advanced tumor cells. According to a 2009 study from Greece, olive leaf crude extracts can inhibit cell proliferation in urinary bladder cancer, breast cancer, and brain cancer (5).
4. Protects against Alzheimer’s and Parkinson’s
Several studies have shown that oleuropein present in olive leaf extract has important neuroprotective properties. According to research published in the International Journal of Molecular Sciences, oleuropein helps counteract the creation of amyloid plaque in the brain, which is characteristic of Alzheimer’s disease (6).
According to another study published in Oxidative Medicine and Cellular Longevity, the olive leaf extract can induce autophagy, achieving a decrease of aggregated proteins and a reduction of cognitive impairment in vivo (7).
5. Reduces arthritis pain
Olive leaf extract contains polyphenols that have anti-inflammatory and antioxidant properties. These extracts have been used for years to treat painful and inflamed joints. According to a 2014 study, the olive oil polyphenols decrease the circulating concentrations of interleukins, a pro-inflammatory cytokine that stimulates the inflammation in diseases like rheumatoid arthritis and cancer (8). Another study from China showed that when rats with arthritis were given olive leaf extract, they experienced a significant reduction in paw swelling (9).
Olive leaf extract can be as effective as blood pressure medication in reducing blood pressure in people with hypertension. Olive leaf extract lowers blood pressure by acting as a calcium channel blocker, which widens blood vessels.
During a 2011 study, participants were given 500 mg of olive leaf extracts twice a day for eight weeks. The results of this study showed that olive leaf extract was as effective as Captopril in reducing blood pressure. The olive leaf extract also helped in the reduction of triglyceride levels (10).
7. Boosts immunity
Olive leaf extract has potent antiviral properties that can help fight against viruses and microbes that cause influenza and other respiratory conditions. Olive leaf extract also stimulates phagocytosis, the process through which the phagocytes engulf and destroy harmful foreign particles like bacteria and viruses.
During a study when 32 high school athletes were given 20 grams of olive leaf extract for nine weeks, there was a 28 percent reduction in the number of sick days (11). Gargling with olive leaf tea can also decrease inflammation and alleviate a sore throat.
Olive leaf extract has antifungal, antibacterial and antiviral properties, and may even be able to treat herpes simplex type-1 virus. This type of herpes, also known as oral herpes, causes sores around the mouth and the lips. According to a 2016 study, the olive leaf extract is effective against HSV type-1 virus (12).
9. Protects skin
When applied to the skin, olive leaf extract can protect against the harsh weather, and pollutants. Its antioxidant properties can alleviate cell damage caused by the harmful UV rays. It slows down the signs of aging, and it nourishes purifies the skin. Olive leaf extracts also eliminate bacteria, so it prevents skin conditions like dermatitis. Olive leaf extracts also enhance circulation, which helps improve complexion and keep it healthy.
According to a 2009 study, when mice with UV ray damage were given olive leaf extracts, it significantly inhibited increases in skin thickness and reduction in skin elasticity, and skin carcinogenesis and tumor growth (13).
10. Has antibacterial and antifungal properties
Olive leaf extract has antibacterial, antifungal, and antiparasitic properties that help in treating infections like candida, pneumonia, shingles, tuberculosis, hepatitis B, and meningitis. During one study from Israel, scientists tested different concentrations of olive leaf extracts against various bacteria and fungi. The results showed that a 0.6% extract of the olive leaf could kill almost all bacteria tested, including candida albicans, and E coli (14).
11. Helps in weight loss
Olive leaf extracts contain oleuropein, which helps to prevent weight gain. According to a 2016 study, when rats with obesity were given oleuropein for eight weeks, it leads to a decrease in body weight, adipose tissue mass, and triglyceride levels (15). This study shows that oleuropein in olive leaf extract can play a significant role in preventing obesity.
Side effects of olive leaf extracts
When taken in safe doses, the olive leaf extract is safe to use. However, oleuropein, the active ingredient I olive leaf extract, can lead to some side effects. It can lower blood pressure in people who already have low blood pressure, which may lead to dizziness. It can also interact with medicines for blood pressure and diabetes. Consult with your doctor to avoid such interactions.
Olive leaf extracts can also cause stomach irritations, diarrhea, acid reflux, stomach pain, and headache. To avoid this, you must dilute this extract or take it in small doses with food throughout the day. Olive leaf extracts can also increase the effect of blood thinners like Warfarin. Consult your doctor before taking olive leaf extract if you are taking blood thinners. Olive leaf extract can also interact with chemotherapy drugs.
Dosage and ways to use
Olive leaf extracts are available in both capsule and liquid form. Since the US Food and Drug Administration (FDA) does not regulate these supplements, look for an extract from a reputable company. Experts recommend a dosage between 500 to 100 mg per day. You can divide this amount into a few doses per day. Start with small doses and gradually increase the dosage. You can also dilute some drops of olive leaf extract and use it on your skin.
Olive leaf extract is derived from the olive tree leaves. Olive leaf extract contains several chemical compounds like oleuropein and hydroxytyrosol and polyphenols and flavonoids including luteolin, rutin, caffeic acid, catechin, and apigenin. It helps to improve heart health, fight diabetes, reduce cancer risk, protect against Alzheimer’s and Parkinson’s, lower arthritis pain, protect the skin, boost immunity, treat herpes, and lower weight.
Though it is the same as taking olive leaf extract, it may cause side effects in some people. People who are taking blood thinners and medication for blood pressure and diabetes should consult with their doctor before taking olive leaf extract.