Shaun Ward MSc ANutr
Eurycoma Longifolia is the name of a herb, also called Malaysian Ginseng or Longjack.
It belongs to the plant family of the Simaroubaceae.
The active components of eurycoma longifolia are quassinoid compounds, eurycolactones, canthin-6-one metabolites, eurylene and teurilene, derivatives of squalene, glycosaponins.
Eurycoma langifolia extract is a patented blend of eurycoma longifolia that consists of 22% eurypeptides and 40% glycosaponins. It is known as a “100:1 extract”, where it has been concentrated so that 1 gram of longjack is equivalent to 100 grams of eurycoma longifolia – at least in terms of the 2 components mentioned.
The Potential Benefits of Eurycoma Longifolia
Below we've listed every possible benefit we could find that had credible scientific backing:
It May Increase Testosterone Levels
The eurypeptide content of eurycoma longifolia is linked to increasing testosterone levels by increasing the activity of the CYP17 enzyme in the testes. This enzyme is partially responsible for increasing the conversion rate of some precursors into dehydroepiandrosterone and other androgens.
In animals with low testosterone, 500mg of eurycoma longifolia per kg of bodyweight appears to increase serum testosterone more than 50% within 2 weeks of ingestion .
However, in animals with normal testosterone levels, 15mg per kg of a concentrated eurycoma extract failed to increase testosterone after 6 weeks .
In humans with low testosterone levels, 200mg of longfolia extract per day was effective in enhancing libido and serum testosterone levels by ~50% after just 1 month .
Similar trials in otherwise healthy individuals fail to replicate these results .
At this point the evidence is clear in showing a potential testosterone-boosting effect, but only in clinically diagnosed states of hypogonadism.
It May Lower Estrogen Levels
In animals studies, injecting 2 quassinoids from eurycoma have been able to induce anti-estrogenic effects similar to a powerful anti-estrogenic drug called Tamoxifen at the same dose .
However, experts hold the opinion that these effects would not be seen in humans who have a poor oral bioavailability of eurycoma.
Despite this, the anti-estrogenic effects are still associated with some anti-cancer effects, such as inhibiting the proliferation of MCF-7 breast cancer cells (highly estrogenic) in lab studies .
There is also potential that these anti-estrogenic effects may be able to increase sperm production in males.
In addition, eurycoma longifolia can improve symptoms of reproductive disorders in females by working to normalize abnormal estrogen cycles .
Although its “in vivo” efficacy is currently unknown, eurycoma longifolia via its eurycomanone content appears to possess potent anti-estrogenic activities.
It May Be an Aphrodisiac
The aphrodisiac effects of eurycoma appear to span a large variety of animal models.
It is claimed this is due to the glycoprotein content of eurycoma, but these hypothesis only stem from nutrition conferences as opposed to peer-reviewed journals .
In regards to animal studies, 500mg of eurycoma longifolia per kg bodyweight every day was able to increase sexual desire by ~25% within a week, and ~40% within 2 weeks – thought to be mediated by an increase in testosterone levels .
When tested in humans, supplementation of 300mg of a water extract daily for 6-12 weeks has also been reported to increase libido by ~10%, as assessed by a self-report survey .
It May Help Sexual Performance
In addition to the aphrodisiac effects, eurycoma can also increase sperm production and may directly act as a proerectile agent.
A molecule within eurycoma known as 9-hydroxycanthin-6-one is associated with both a delay in ejaculation as well as pro-erectile properties.
These effects may be a primary or secondary mechanism to the aphrodisiac properties of eurycoma longifolia, seeing a dose-dependent increase in the frequency of erections in animals .
Other animals research indicates that direct injections of up to 0.2-1mg of eurycoma extract can also increase penile pressure and delay ejaculation  (this should not be tried at home!).
How To Take Eurycoma Longifolia?
The standard dose of eurycoma longifolia extract is 200-300mg of a 100:1 extract (the concentration is based on the eurycomamone content) – split into two separate doses each day.
Current research cannot be sure this dose is “optimal”, but it is at least effective and safe.
Eurycoma Longifolia Safety And Side Effects
Eurycoma longifolia extract has been reported as a safe supplement if people stick to the standard doses.
Given, the toxicity dose of eurycoma longfolia extract has been found to be ~1,200mg per day in humans, which is only ~4 times more than the recommended dose .
For this reason, it is important to only use these supplements from very reputable brands that have undergone strict product testing.
This is especially important when considering that eurycoma longifolia supplements in Malaysia have been found to contain mercury, lead, and viagra!
Eurycoma Longifolia is a herb from the plant family of the Simaroubaceae.
The supplemental extract of this herb may be able to normalize testosterone and estrogen levels in people with hormonal conditions.
It also seems to have potent effects on increasing sexual desire and performance, albeit this has only been proven in animal studies.
People need to be aware not to use high doses of this supplement, as the current recommended intakes are close to the amounts required for toxicity to occur. Do not consume more than 300mg of eurycoma longifolia extract per day.