Olive (Olea europaea) leaves, an agricultural waste or by-product, are a great source os natural antioxidants. Olive leaves contain various polyphenols (also known as biophenols), such as oleuropein and oleacein. Polyphenols occur naturally in plants and contribute to the health benefits of olive leaf extract. Besides polyphenols, the leaves of the olive tree are rich in antioxidants, such as ligstroside isomers, hydroxytyrosol, tyrosol and caffeic acid.
Olive leaf extract is the concentrate of phytochemicals in olive leaves and contains thereby a high amount of powerful antioxidants. Olive leaf extract is traditionally used to boost the immune system. For instance, it is administered to ameliorate symptoms of the common cold, coughs, and sore throats.