Tongkat Ali (Long jack, Eurycoma longifolia) Review: Effective For Boosting Testosterone Naturally?

Tongkat Ali (Long jack, Eurycoma longifolia) Review: Effective For Boosting Testosterone Naturally?

You may see it called Tongkat Ali, Eurycoma longifolia, or even Long jack. More than likely, you’ll find it gracing the ingredients panel of your favorite natural testosterone booster — wedged in with other old time favorites like tribulus, DHEA, Testofen, and so on.

If you believe the sort of hype touted by advertisers in popular magazines and on the Internet, you could be forgiven for thinking that Tongkat, Eurycoma, or whatever you want to call it, is used by body building’s elite professionals, and rivals anabolic steroids in its effectiveness.

An evergreen tree native to Thailand, Malaysia and Indonesia, Tongkat Ali has been used by the native peoples for centuries as a natural aphrodisiac, general tonic and energy booster. But does it really have amazing anabolic and test-boosting powers?

There’s one human study – a conference abstract in the British Journal Of Sports Medicine (Br. J. Sports Med. 37: 464-70).

It did have positive results, although no measurements for testoterone are reported.

However, conference abstracts are not the same a full published article in a reputable journal.

And, as Elissa pointed out to me, this study was done in 2003, so you’d think it would have been submitted to a journal by now if it were more than the paper it was printed on.

OK, but what about the “studies” you’ve no doubt seen referenced by retailers selling Eurycoma / Longjack / Tongkat based products?

Most of these refer to animal studies — specifically studies that show Tongkat’s ability to boost the libido of middle-aged to old rats (see Phytomedicine. 2003;10(6-7):590-3, Exp Anim. 2000 Jan;49(1):35-8, J Basic Clin Physiol Pharmacol. 2004;15(3-4):303-9).

Of course, I don’t need to tell you that such benefits don’t necessarily transfer from humans to rats. The other issue to consider is dosage. These rats were getting one heck of a dose — somewhere in the range of 200/400/800 mg/kg, depending on the study. A human-equivalent dose for a 180 lb. guy (approximately 82 kg) would need to take between approx. 2.7 grams (2,700 mg) to 10.6 grams (10,600 mg) of Tongkat Ali to get a comparable dosage.

That’s outrageous and expensive. And it may not be entirely safe, either.

Second, while an increase in rat libido is conclusively demonstrated in all studies, it is not clear whether this increase is a result of androgen production or some other mechanism.

What do this really mean? What’s the bottom line here?

Tongkat / Longjack / Eurycoma is an interesting substance to be sure. But it needs to be thoroughly studied on human subjects by independent researchers before any conclusive “test-boosting” claims can be made. For now, there simply isn’t the evidence available to indicate this is the case.

Author: Paul

Paul Crane is the founder of His passions include supplements, working out, motorcycles, guitars... and of course, his German Shepherd dogs.

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