From:
http://www.anthony-roberts.com/blog/?p=158
I did a bunch of research on “long jack” (Eurycoma longifolia Jack) because it’s been talked about quite a bit lately. In truth, I’m sure people will think I’m biased because I produce my own Test boosting supplement..but here’s what I’ve found…
Ok…there’s been plenty of questions about this stuff. Through my research in peer-reviewed medical journals (and only medical journals, not anthing else) here is what this stuff has ACTUALLY been shown to do. I’m going to reserve any personal comments on the product, and will basically sum up the articles I read. Then after the references, I’ll give you my thoughts.
1. Increase Libido and act as an aphrodesiac (1-10). Noteworthy is that not a single study which showed ELJ to increase libido made any mention of it raising testosterone or androgen levels…though admittedly, they didn’t examine those parameters.
2. Appears not to be cytotoxic against several cell lines and normal kidney cell lines. (11)
3. Eurycomanone (from ELJ) very poor oral bioavailability. (12)
4. Exibits potential anti-hyperglycaemic effects. (13)
5. Is cytotoxic against human breast cancer and human lung cancer (14)
6. Has potential anti-tumor and anti-parasitic effects (15)
7. Appears to be androgenic (7) and anabolic when used in doses ranging from 200-800mg/kg (16).
8. Potentially anti-malarial (17)
9. Over 5 weeks of using 100mgs/day of ELJ, one study found that people using it gained 5lbs of LBM (control group gained nothing), lost 2.86%bf (control group lost more than half of that amount too), 1RM went up 5kgs (control went up just under half of that), and 1.8cm was gained on arm size (nothing for control). (18)
References:
1. Eurycoma longifolia Jack enhances sexual motivation in middle-aged male mice.J Basic Clin Physiol Pharmacol. 2003;14(3):301-8.
PMID: 14964739 [PubMed - indexed for MEDLINE]
2. Effects of Eurycoma longifolia Jack on sexual qualities in middle aged male rats.Phytomedicine. 2003;10(6-7):590-3.
PMID: 13678248 [PubMed - indexed for MEDLINE]
3. Effect of Eurycoma longifolia Jack on orientation activities in middle-aged male rats. Fundam Clin Pharmacol. 2002 Dec;16(6):479-83.
PMID: 12685506 [PubMed - indexed for MEDLINE]
4. Effect of Eurycoma longifolia Jack on libido in middle-aged male rats.
J Basic Clin Physiol Pharmacol. 2002;13(3):249-54.
PMID: 12670032 [PubMed - indexed for MEDLINE]
5. Aphrodisiac evaluation in non-copulator male rats after chronic administration of Eurycoma longifolia Jack.
Fundam Clin Pharmacol. 2001 Aug;15(4):265-8.
PMID: 11564133 [PubMed - indexed for MEDLINE]
6. Evaluation of the potency activity of aphrodisiac in Eurycoma longifolia Jack.Phytother Res. 2001 Aug;15(5):435-6.
PMID: 11507738 [PubMed - indexed for MEDLINE]
7. 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.
PMID: 10803359 [PubMed - indexed for MEDLINE]
8. Eurycoma longifolia JACK and orientation activities in sexually experienced male rats.
Biol Pharm Bull. 1998 Feb;21(2):153-5.
PMID: 9514610 [PubMed - indexed for MEDLINE]
9. Eurycoma longifolia Jack enhances libido in sexually experienced male rats.Exp Anim. 1997 Oct;46(4):287-90.
PMID: 9353636 [PubMed - indexed for MEDLINE]
10. Sexual arousal in sexually sluggish old male rats after oral administration of Eurycoma longifolia Jack.
J Basic Clin Physiol Pharmacol. 2004;15(3-4):303-9.
PMID: 15803965 [PubMed - indexed for MEDLINE]
11. Cytotoxic effects of the root extracts of Eurycoma longifolia Jack.
Phytother Res. 2005 Nov;19(11):994-6.
PMID: 16317660 [PubMed - indexed for MEDLINE]
12. Bioavailability and pharmacokinetic studies of eurycomanone from Eurycoma longifolia.
Planta Med. 2005 Sep;71(9):803-7.
PMID: 16206032 [PubMed - indexed for MEDLINE]
13. Screening for antihyperglycaemic activity in several local herbs of Malaysia.
J Ethnopharmacol. 2004 Dec;95(2-3):205-8.
PMID: 15507337 [PubMed - indexed for MEDLINE]
14. Cytotoxic and antimalarial beta-carboline alkaloids from the roots of Eurycoma longifolia.
J Nat Prod. 2003 Oct;66(10):1324-7.
PMID: 14575431 [PubMed - indexed for MEDLINE]
15. 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. Erratum in: J Ethnopharmacol.2003 Mar;85(1):173.
PMID: 12169407 [PubMed - indexed for MEDLINE]
16. 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.
PMID: 11693547 [PubMed - indexed for MEDLINE]
17. Cytotoxic and antimalarial constituents of the roots of Eurycoma longifolia.
J Nat Prod. 1991 Sep-Oct;54(5):1360-7.
PMID: 1800638 [PubMed - indexed for MEDLINE]
18. Hamzah, S., and Yusof, A (2003) The ergogenic effects of eurycoma longifolia jack: A pilot study. British Journal of Sports Medicine. 37:464-470
Does this stuff have anaboilc effects? Certainly, when you inject 800mgs/kg of it, it can be anabolic. But in reality, Who knows? Most of the studies on it seem to be using an injectable solution, and not an oral version of the product…we all know that injectable testosterone is anabolic, but if you take that same bottle of Test E and drink it, it’ll do nothing even if you drink 5 bottles a day. When you combine that with the poor oral bioavailability of Long Jack, I doubt it’s going to be a really hot product in pill form. The oral bioavailability (of a quassiniod of ELJ) when compared to IV dosing, is far less (even when 5x the IV dose is given).
The study on 100mgs/day was actually decent, and the people who were studied gained about double what the control group had gained. Still…it was a pilot study and from what I saw, the parameters weren’t ideal. If we want to pin our hopes on this stuff working, this study (7 men) is all we have. From the abstract I read, testosterone levels were not measured in this study. They work off the assupmtion that test levels are increased, but they never measure that. The place they got this assumption was not a scientific journal or medical study, but rather a speech and proceedings paper at the “Asian Conference of Sexology” from 2002. It is, of course, Very shady to use that speech as a reference to show that something increases test. Very shady indeed. To my mind, that really is poor form. This study (that I referenced) was really only accepted because it’s a pilot study. TO go off the assumption that something increases test because a speaker at the Asian Conference of Sexology said so is very disconcerting and should be disregarded as any kind of proof.
Still, it has been used by natives in Malaysia as an aphrodesiac, so it probably gives you some kind of boost in libido…but that is a far cry from saying it increases testosterone levels. I wouldn’t be surprised to find out it has very mild effects on libido, but as far as being something that increases testosterone, I haven’t been able to find anything that would suggest that.
The effects it has on certain forms of breast cancer and libido, and the anabolic/androgenic effects it has (in SUPER HIGH doses) lead me to believe that it has potential, at best. But when you are talking about an injected dose of 800mgs/kg, and then comparing it to an adult who is taking 300mgs/day…I don’t think that we can expect anything special.
On another note…remember, these are medical studies…and were published in peer-reviewed medical journals. Unless there is some kind of issue with my ability to search medical journals, google, etc…because I literally spent hours looking this stuff up…there’s nothing I would say to be credible showing it increases test (for now).
Jury on this stuff is out for now. I would stick with a proven test booster…or at least one that has a study (or real bloodwork) showing it boosts test.