Supplement · Adaptogens & traditional herbs
Tongkat ali (longjack)
Also known as: Eurycoma longifolia, Longjack
A herb with reasonably encouraging early evidence for testosterone and stress.
- Evidence
- Silver· human data
- Sources cited
- 1
- Last reviewed
- 22 July 2026
Tongkat ali is a Southeast Asian herb used for libido, stress and 'male vitality', with quassinoids (such as eurycomanone) as active compounds.
Among 'testosterone' herbs it has some of the more encouraging early data: small trials suggest it may raise testosterone (especially in men with low levels or under stress), lower cortisol and improve wellbeing. The evidence remains preliminary, and extract standardisation varies widely between products.