A Southeast Asian root with the most human research behind it in this formula, studied around testosterone and stress markers.
Tongkat Ali, also called longjack, is the root of Eurycoma longifolia, a tree native to Southeast Asia's rainforests, with a long history of traditional use for stamina and vitality.
It's the botanical here with the most human data — studies in stressed adults report lower cortisol and improved mood alongside changes in free testosterone.
Trials most often use 200-400mg of a standardized extract alone. Extract quality and eurycomanone content matter, and neither is published for every formula on the market.
This describes general research on Tongkat Ali (Eurycoma longifolia) itself, not the finished Primordial Vigor X product, which hasn't been the subject of its own clinical trial. See the full ingredients list or the formula overview for more.