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Eurycoma Longifolia: The Longjack Herb -- Long On Benefits
Eurycoma longifolia is a Malaysian shrub, used in traditional medicine for male sexual enhancement and as a general tonic. It is reputed to be a great aid to male sexual stamina. It is referred to as Tongkat Ali or Longjack in Malaysia and elsewhere. Traditionally, the "Longjack" roots were brewed for long hours to get a bitter extract. Today, modern concentration methods allow us to obtain standardized concentrates in capsules.

Aphrodisia & Testosterone

The main traditional use of Eurycoma has been as an aphrodisiac and tonic, and for these purposes the herb has a long and vivid history. Used widely throughout the Pacific Rim and Indonesia, it is sometimes called "the plant that cures 101 diseases". Whatever its value as a general tonic in different health problems, the one property that traditional users agree on is that it is very powerful stuff for boosting male potency. Animal studies have shown that Eurycoma induces sexual arousal and activity, not unlike the effect of testosterone itself. Eurycoma does in fact have testosterone-like effects on male rats, and in in vitro ("test tube") studies. For example, Eurycoma extract dose-dependently boosts mounting frequency -- the number of times the male rats attempted copulation with females. Some of the animal studies have indicated that increases in serum testosterone levels with Eurycoma supplementation can range from 300% to nearly 500%! Plus, the extract, added in vitro to human testicular tissue, causes an increase of over 400% in testosterone production. Apparently Eurycoma increases the activity of steroidogenic (testosterone-producing) enzymes, as well as increasing cyclic AMP, which also has a favorable effect on steroid synthesis (among other benefits, including fat loss). The initial indicator suggests Eurycoma is set to become one of the heavy-hitters in our testosterone-boosting (and virility-enhancing) natural medicine chest.

A Trial in Athletes
One unpublished, placebo-controlled human study from the Department of Exercise Physiology and the University of Malaya (Kuala Lumpur) tested the effect of Eurycoma -- only 100 mg/day of the LJ100 extract -- for eight weeks in young healthy males undertaking resistance training. The results were impressive, and included:
  • The LJ100 treatment group showed a greater loss of bodyfat percentage than the placebo group -- 9.1% versus 6.6%.
  • The LJ100 treatment group gained more muscle strength, as indicated by the one-rep-maximum test: 6.8% gain versus 2.8%.
  • The LJ100 treatment group also gained more muscle mass, the mean arm circumference being increased significantly by 1.8 cm (about one inch), while there was no change in the placebo group.
  • Compared to other Tongkat Ali / Eurycoma sources that provide an 8% improvement in serum testosterone, LJ-100(TM) increases testosterone levels 100% after 2 weeks.
The authors of the study attributed the benefits to increased testosterone levels, and possibly increases of basal metabolism (to account for the loss of bodyfat).

What's IN This Stuff?
 Unfortunately, the mechanism of action and "active ingredients" of Eurycoma have not yet been positively identified. We know that the plant has a variety of constituents such as beta-carbolines, quassinoids, canthinone alkaloids, squalene congeners, triterpenes, and neolignans. Hopefully more studies will reveal the precise active constituents that can then be more precisely concentrated and standardized in preparations for supplemental use.

Go For The Quality - LJ100
The highest quality Eurycoma or "Longjack" material comes directly from Malaysia. The traditional medicinal benefits of the plant are known to come primarily from the root; the best Malaysian roots are aged seven years or more. Eurycoma is available in extracts of increasing potency: 20:1, 50:1, and 100:1. The latter -- the best of the best -- is called "LJ100", and it is the stuff to look for when you buy a Eurycoma product.

Side Effects?
 In its traditional context, Eurycoma seems to be free of serious side effects. Some users have found Eurycoma stimulating, presumably due to its effect on increasing cyclic AMP. Users have also reported noticeable increases in strength after using just a few doses of LJ100 based products. This is most likely attributable to increased testosterone levels. All in all, feedback from users indicate numerous positive effects and no reported negative effects. Eurycoma, like other powerful supplements, might best be cycled rather than taken continuously.
Bibliography Ang HH, Cheang HS, Yusof AP. Effects of Eurycoma longifolia Jack (Tongkat Ali) on the initiation of sexual performance of inexperienced castrated male rats. Exp Anim. 2000 Jan;49(1):35-8. Ang HH, Cheang HS. Effects of Eurycoma longifolia jack on laevator ani muscle in both uncastrated and testosterone-stimulated castrated intact male rats. Arch Pharm Res. 2001 Oct;24(5):437-40. Ang HH, Cheang HS. Studies on the anxiolytic activity of Eurycoma longifolia Jack roots in mice. Jpn J Pharmacol. 1999 Apr;79(4):497-500. Ang HH, Lee KL. Kiyoshi M. Eurycoma longifolia Jack enhances sexual motivation in middle-aged male mice. J Basic Clin Physiol Pharmacol. 2003;14(3):301-8. Ang HH, Lee KL. Effect of Eurycoma longifolia Jack on libido in middle-aged male rats. J Basic Clin Physiol Pharmacol. 2002;13(3):249-54 Ang HH, Lee KL. Effect of Eurycoma longifolia Jack on orientation activities in middle-aged male rats. Fundam Clin Pharmacol. 2002 Dec;16(6):479-83. Bedir E, et al. Eurycomaoside: a new quassinoid-type glycoside from the roots of Eurycoma longifolia. Chem Pharm Bull (Tokyo). 2003 Nov;51(11):1301-3. Hamzah, SH, Yusof, A. The Anabolic Effects of LJ100. Department of Exercise Physiology, Sports Centre, University of Malaya, Kuala Lumpur. Kuo PC, et al. Cytotoxic and antimalarial beta-carboline alkaloids from the roots of Eurycoma longifolia. J Nat Prod. 2003 Oct;66(10):1324-7. Kuo PC, Damu AG, Lee KH, Wu TS. Cytotoxic and antimalarial constituents from the roots of Eurycoma longifolia. Bioorg Med Chem. 2004 Feb 1;12(3):537-44. Jiwajinda S, et al. In vitro anti-tumor promoting and anti-parasitic activities of the quassinoids from Eurycoma longifolia, a medicinal plant in Southeast Asia. J Ethnopharmacol. 2002 Sep;82(1):55-8. Satayavivad J, et al. Toxicological and antimalarial activity of eurycomalactone and Eurycoma longifolia Jack extracts in mice. Thai J Phytopharmacy. 1998 Dec; 5(2):14-27. M.I.M Tambi, S. Othman, and J.M. Saad "Water-soluble extract of LJ100(TM) as a potential natural energizer for healthy aging men" Specialist Reproductive Research Center, National Population & Family Development Board,Ministry of Women and Family Development, Malaysia. Department of Biochemistry, Faculty of Medicine, University of Malaya, Malaysia. Courtesy of Source-1-Global product literature for LJ-100(TM)