Since ancient times, the olive tree has been harvested for its wood, food and oil. Today, many physicians and patients are utilizing the olive tree for the healing properties of olive leaf extract.
The active ingredient in olive leaf extract is oleuropein; this is part of a compound in the olive tree which makes it strongly resistant to insects and bacteria. Oleuropein is derived from the bitter part of olives, which is eliminated from them when they are cured. Oleuropein is an iridoid, or a type of plant chemical, found throughout the olive tree and in olive oil.
Healing properties of olive leaves were first discussed in medical literature in an 1854 medical journal article by Daniel Hanbury, M.D., a British physician. Hanbury boiled the leaves and used the liquid to treat people stricken with fever and malaria contracted in Britain’s tropical colonies. Dr. Hanbury correctly speculated that a bitter substance in the leaves acted as the healing ingredient: years later, scientists isolated this and named it oleuropein.
In the 1960s, European researchers found that the active ingredient in oleuropein, elenolic acid, exerts powerful anti-bacterial effects. Toward the end of the decade, research suggested that elenolic acid also helps stops the growth of viruses, including those associated with the common cold.
According to Dr. James R. Privitera, “The key thing for consumers to remember when choosing olive leaf extracts, is to buy ones which contain at least 5% oleuropein. 5% is the national standard,” he says, “and some manufacturers don’t list their percentages, which means that consumers don’t always know what they’re getting.”