Trinity College biochemist believes the plant we associated with stealing kisses at Christmas kills tumor, with its “anti-cancer chemical”.
It’s an Irish Christmas staple that's closely associated with triggering love and romance over the festive season.
But stealing a kiss under the mistletoe may not be the only benefit of this ancient plant - as scientists believe it could offer an effective treatment for some types of cancer.
Trinity College Dublin-based biochemistry Professor Luke O'Neil said: "There's a very interesting chemical in mistletoe which kills tumors. It's an anti-cancer chemical.
"There are tiny amounts of the chemical that might kill tumors and there's a trial happening in Germany as we speak, so mistletoe's a very interesting plant."
Mistletoe's association with romance stretches back to Norse mythology, while Celtic druids considered the mystical plant to be a treatment for many illnesses.
The more recent Christmas tradition of kissing under the mistletoe can be traced back to the late 18th century.
But despite the much-loved festive custom, mistletoe - of which most species have waxy, white berries - is actually a tree-killing parasite plant.
There are approximately 1,300 species of the plant, some of which have red, pink or transparent berries - and all of which are poisonous.
According to one French tradition, the reason that mistletoe is poisonous is because the plant was growing on a tree that was used to make the cross on which Jesus was crucified.
Read more: The Right to Die is the next big Irish issue