Tongkat ali, also called long jack, and also known by very many native names, is a small flowering plant of the Simaroubaceae family. The plant’s scientific name is Eurycoma longifolia, and it is found throughout South East Asia, especially in Malaysia and Indonesia. The quassinoids, or bitter tasting extracts from the roots, are used in native medicine, where they are said to have a great many desirable properties, including anti-diabetic, anti-malarial, anti-bacterial and anti-cancer effects. Many of these effects have been studied by Western medical science, and results have been published in many respected journals. The identified effect of increasing testosterone levels have been noted in body building circles. There are several body-building supplements marketed as containing Eurycoma, or tongkat ali.