The Effects of Olive Leaf Extracts

Disclaimer: Results are not guaranteed*** and may vary from person to person***.

Olive Leaf ExtractOlives have been a part of our history for thousands of years. The olive tree is an evergreen that originates from Crete—the leaves were used to cleanse wounds as far back as 3,500 BC. Olive leaves were also first used to treat heart ailments in ancient regions of the Mediterranean and Egypt.

The tree is cultivated in areas similar to the climates we see in America. The small, leathery leaves are grey-green on top, with fine, white, scale-like hairs on the side. The leaves are gathered in bunches throughout the year.

Traditionally, olive leaves were worn by athletes at ancient Olympic events. Today, olive leaf extracts are known for their antioxidant, antiviral, and antimicrobial properties, including resisting insect and microbial attacks.

Olive leaves are shown to possess hypotensive properties when used in animal experiments. Olive leaf extracts also possess antispasmodic, vasodilator, and antiarrhythmic properties. The hypoglycemic and thyroid enhancing activities of olive leaves have also been demonstrated in animal tests.

Although these benefits are essential, clinical trials have not yet been performed to support the use of olive leaf extract for antioxidant and antiviral activity. There are, however, potential side effects of using olive leaf extracts—up until a few years ago, the side effects were unknown to scientists.

Olive Leaf Extracts Side Effects

1. Herxheimers reaction: One of the most common side effects of olive leaf extract is a temporary deterioration of symptoms—an immune reaction to the release of toxins from pathogens that have been damaged by, in this case, olive leaf extracts. The reaction proceeds as follows:

  • Olive leaf compounds destroy the cells of a large number of pathogens.
  • The pathogens secrete toxins and are taken in by surrounding tissues.
  • Toxins cause swelling, pain, and histamine-release.
  • The body cleanses and detoxifies itself, resulting in further uncomfortable symptoms.

Side effects include:

  • Body pain
  • Dull headaches
  • Joint and muscle pains
  • Sore throat
  • Severe sweating, fever, and vaginal discomfort

Side effects are typically mild and usually only last for a few days. If you experience any of these side effects, drink six to eight glasses of water daily to help the body eliminate the toxins.

2. Stomach irritation: This symptom can occur for people who are consuming strong tinctures or olive leaf extract capsules. To minimize irritation, take the capsule with food. For tinctures, dilute them in water until the alcohol concentration is about 20%. It also helps to drink six to eight glasses of water a day to help the body eliminate toxins.

3. Dizziness: Dizziness tends to occur in people who already suffer from low blood pressure. If this occurs, take small doses of olive leaf extracts until your body gets used to it.

4. Heartburn: Some people experience heartburn after ingesting olive leaf tinctures. For a soothing remedy, dilute the tincture in water or tea—or try consuming unflavored tincture.

5. Diarrhea: Diarrhea can be caused by stomach irritation. Candida albicans form filaments that place themselves in the stomach lining, in place of useful probiotic bacteria. When the extract destroys the filaments, a Herxheimer reaction could occur, which causes loose stool (diarrhea).


People who are taking medications for certain diseases may want to avoid using olive leaf extracts. For example, people who are taking diabetes medication may want to avoid olive leaf extracts because it might increase their blood sugar levels. Diabetes medication is supposed to lower the blood sugar levels—if mixed with olive leaf extracts, your blood sugar levels could drop too low.

Furthermore, combining medication for blood pressure with olive leaf extract could cause your blood pressure levels to dip too low. Diabetics and people with low blood pressure should avoid olive leaf extracts. Also keep in mind that tests surrounding the benefits of olive leaf extracts have only been conducted on animals—there are no significant studies or research that can prove with certainty that it is safe for humans.

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