Eurycoma longifolia or Tongkat Ali as its commonly known is an herbal medicinal plant found in South East Asian countries such as Malaysia, Vietnam, Java, Sumatra, and Thailand.
Tongkat Ali root is a popular anti-aging and testosterone boosting herbal remedy, which appears to have significant aphrodisiac and pro-fertility properties, especially in males.
Scientific research has found Tongkat Ali to have a range of medicinal benefits including acting as a general tonic, improving mental and physical energy levels, stimulating the release of free testosterone, reduce stress, improve sex drive and overall quality of life.
Tongkat Ali root (Malaysian Ginseng) appears to be a safe medicinal herb for supporting hormonal balance in mildly stressed individuals.
Tongkat Ali For Reducing Cortisol & Increasing Testosterone Levels
Significant improvements were found in the Tongkat Ali group for Tension (−11%), Anger (−12%), and Confusion (−15%).
Stress hormone profile (salivary cortisol and testosterone) was significantly improved by Tongkat Ali supplementation, with reduced cortisol exposure (−16%) and increased testosterone status (+37%).
These results indicate that daily supplementation with Tongkat Ali root extract improves stress hormone profile and certain mood state parameters, suggesting that this “ancient” remedy may be an effective approach to shielding the body from the detrimental effects of “modern” chronic stress, which may include general day-to-day stress, as well as the stress of dieting, sleep deprivation, and exercise training. 
1. Effect of Tongkat Ali on stress hormones and psychological mood state in moderately stressed subjects
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