Olive leaf

Olive leaf is the leaf of the olive tree (Olea europaea). Although olive oil is well known for its flavor and health benefits, the leaf has been used medicinally in various times and places. Olive leaf and olive leaf extracts (OLE), are now marketed as anti-aging, immunostimulator, antioxidant, cardio protective, blood sugar regulating, anti-inflammatory and antibiotic agents. Though there is some laboratory evidence for these effects in biological standardization experiments (i.e., bioassays), clinical evidence in humans is inconclusive.

Olive leaves are sometimes chopped and added to oregano by unscrupulous producers and processors.

The silvery green leaves are oblong, measuring 4–10 centimetres (1.6–3.9 in) long and 1–3 centimetres (0.39–1.2 in) wide. When consumed, leaves have an astringent bitter taste.

The primary active compounds in unprocessed olive leaf are believed to be the antioxidants oleuropein and hydroxytyrosol, as well as several other polyphenols and flavonoids, including oleocanthal.Elenolic acid is a component of olive oil and olive leaf extract. It can be considered as a marker for maturation of olives. Oleuropein, together with other closely related compounds such as 10-hydroxyoleuropein, ligstroside and 10-hydroxyligstroside, are tyrosol esters of elenolic acid.

Historically the benefits of olive leaves have been widely touted, and been used by various cultures for both medicinal and nutritional uses. In the Mediterranean region, olive leaves have been used for the treatment of complaints including high blood pressure, inflammation, arthritis, fever and high blood sugar. The phenolic compounds of the olive tree are concentrated in the leaves, and contain phenolic compounds including oleuropein, hydroxytyrosxol, tyrosol, luteolin, rutin, caffeic acid, catechin and apigenin.

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