Effect of Tongkat Ali on stress hormones and psychological mood state in moderately stressed subjects

Abstract

Background
Eurycoma longifolia is a medicinal plant commonly called tongkat ali (TA) and “Malaysian ginseng.” TA roots are a traditional “anti-aging” remedy and modern supplements are intended to improve libido, energy, sports performance and weight loss. Previous studies have shown properly-standardized TA to stimulate release of free testosterone, improve sex drive, reduce fatigue, and improve well-being.

Methods
We assessed stress hormones and mood state in 63 subjects (32 men and 31 women) screened for moderate stress and supplemented with a standardized hot-water extract of TA root (TA) or Placebo (PL) for 4 weeks. Analysis of variance (ANOVA) with significance set at p < 0.05 was used to determine differences between groups.

Results
Significant improvements were found in the TA group for Tension (−11%), Anger (−12%), and Confusion (−15%). Stress hormone profile (salivary cortisol and testosterone) was significantly improved by TA supplementation, with reduced cortisol exposure (−16%) and increased testosterone status (+37%).

Conclusion
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.

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Effect of Tongkat Ali on stress hormones and psychological mood state in
moderately stressed subjects
Journal of the International Society of Sports Nutrition 2013, 10:28 doi:10.1186/1550-2783-10-28
Shawn M Talbott (smtalbott@supplementwatch.com)
Julie A Talbott (jatalbott@supplementwatch.com)
Annie George (annie.g@biotropicsmalaysia.com)
Mike Pugh (mike.pugh@monavie.com)
ISSN 1550-2783
Article type Research article
Submission date 19 February 2013
Acceptance date 18 May 2013
Publication date 26 May 2013
Article URL http://www.jissn.com/content/10/1/28
This peer-reviewed article can be downloaded, printed and distributed freely for any purposes (see
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© 2013 Talbott et al.
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which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Effect of Tongkat Ali on stress hormones and
psychological mood state in moderately stressed
subjects
Shawn M Talbott1*
* Corresponding author
Email: smtalbott@supplementwatch.com
Julie A Talbott1
Email: jatalbott@supplementwatch.com
Annie George2
Email: annie.g@biotropicsmalaysia.com
Mike Pugh3
Email: mike.pugh@monavie.com
1 SupplementWatch, 648 Rocky, Knoll Draper, UT 84020, USA
2 Biotropics Malaysia Berhad, Lot 21, Jalan U1/19, Section U1, Hicom-
Glenmarie Industrial Park, 40150 Shah Alam, Selangor, Malaysia
3 MonaVie, 10855 S River Front Parkway, South Jordan, UT 84095, USA
Abstract
Background
Eurycoma longifolia is a medicinal plant commonly called tongkat ali (TA) and “Malaysian
ginseng.” TA roots are a traditional “anti-aging” remedy and modern supplements are
intended to improve libido, energy, sports performance and weight loss. Previous studies
have shown properly-standardized TA to stimulate release of free testosterone, improve sex
drive, reduce fatigue, and improve well-being.
Methods
We assessed stress hormones and mood state in 63 subjects (32 men and 31 women) screened
for moderate stress and supplemented with a standardized hot-water extract of TA root (TA)
or Placebo (PL) for 4 weeks. Analysis of variance (ANOVA) with significance set at p < 0.05
was used to determine differences between groups.
Results
Significant improvements were found in the TA group for Tension (−11%), Anger (−12%),
and Confusion (−15%). Stress hormone profile (salivary cortisol and testosterone) was
significantly improved by TA supplementation, with reduced cortisol exposure (−16%) and
increased testosterone status (+37%).

Conclusion
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.
Keywords
Testosterone, Cortisol, Stress, Vigor, Tongkat ali, Eurycoma, Mood
Background
Eurycoma longifolia is an herbal medicinal plant found in South East Asia (Malaysia,
Vietnam, Java, Sumatra, Thailand). In Malaysia, it is commonly called tongkat ali and has a
range of medicinal properties as a general health tonic, including improvement in physical
and mental energy levels and overall quality of life [1,2]. The roots of tongkat ali, often
called “Malaysian ginseng,” are used as an adaptogen and as a traditional “anti-aging”
remedy to help older individuals adapt to the reduced energy, mood, and libido that often
comes with age [3-7]. In modern dietary supplements, tongkat ali can be found in a variety of
products intended to improve libido and energy, restore hormonal balance
(cortisol/testosterone levels) and enhance both sports performance and weight loss. The
objective of this study was to evaluate the effects of tongkat ali extract on stress hormone
balance (cortisol/testosterone) and psychological mood state in moderately stressed subjects.
In both men and women, testosterone levels peak between 25 to 30 years of age - and
thereafter drop approximately 1-2% annually [8,9]. At the age of 60, testosterone levels are
typically only 40-50% of youthful levels and may be lower due to stress and related lifestyle
issues such as diet, exercise, and sleep patterns [10,11]. The benefits of maintaining a
youthful testosterone levels are many, including increased muscle mass and reduced body fat,
high psychological vigor (mental/physical energy), and improved general well-being [12,13].
Eurycoma contains a group of small peptides referred to as “eurypeptides” that are known to
have effects in improving energy status and sex drive in studies of rodents [14-16]. The
effects of tongkat ali in restoring normal testosterone levels appears to be less due to actually
“stimulating” testosterone synthesis, but rather by increasing the release rate of “free”
testosterone from its binding hormone, sex-hormone-binding-globulin (SHBG) [17,18]. In
this way, eurycoma may be considered not so much a testosterone “booster” (such as an
anabolic steroid), but rather a “maintainer” of normal testosterone levels and a “restorer” of
normal testosterone levels (from “low” back “up” to normal ranges) [19]. This would make
eurycoma particularly beneficial for individuals with sub-normal testosterone levels,
including those who are dieting for weight loss, middle-aged individuals suffering with
fatigue or depression, and intensely training athletes who may be at risk for overtraining
[20,21].

Traditional use
Decoctions of tongkat ali roots have been used for centuries in Malaysia and Southeast Asia
as an aphrodisiac for loss of sexual desire and impotence, as well as to treat a range of
ailments including post-partum depression, malaria, high blood pressure, and fatigue [22].
Tongkat ali has been referred to as Malaysia’s “home-grown Viagra” [4] with the Malaysian
government investing considerable effort to license, develop, and sustain research into the
potential health benefits of Eurycoma longifolia through a variety of governmental
organizations, including the Forest Research Institute of Malaysia (FIRM) [22].
Modern extracts
Numerous commercial tongkat ali supplements claim “extract ratios” from 1:20 to 1:200
without any information about bioactive constituents, extraction methodology (e.g. ethanol
versus water), or extract purity. Alcohol extracts of eurycoma have been studied in mice for
antimalarial effects of concentrated eurycomalactone [23] but also exhibit toxic effects at
high doses (LD50 at 2.6 g/kg), which would preclude safe use in humans as a long-term
dietary supplement [24,25]. In contrast, hot-water root extracts standardized for known
bioactive components (1% eurycomanone, 22% protein, 30% polysaccharides, 35%
glycosaponin) have been demonstrated to be extremely safe at high doses and for long-term
consumption [26-28].
Properly standardized hot-water extracts [2,26,29] have a distinctly bitter taste due to the
presence of quassinoids, which are recognized as some of the bitterest compounds in nature
[30,31]. Tongkat ali extracts that do not taste bitter are either not true Eurycoma longifolia
root (there are many commercial examples of “fake” tongkat ali extracts) or are sub-potent in
terms of bioactive constituents, and thus would also be expected to have low efficacy.
Because of tongkat ali’s reputation for libido benefits, there are several examples of dietary
supplements labeled as Eurycoma longifolia, but containing none of the actual root, and
instead being “spiked” with prescription erectile dysfunction drugs including tadalafil/Cialis,
sildenafil/Viagra, and vardenafil/Levitra [4, personal communication].
Laboratory and animal research
Bhat and Karim [1] conducted an ethnobotanical and pharmacological review on tongkat ali,
noting that laboratory research such as cell assay studies offer possible mechanistic support
for the myriad traditional uses of tongkat ali, including aphrodisiac [32], antimalarial [33],
antimicrobial [34], anti-cancer [35], and anti-diabetic effects [36].
Numerous rodent studies exist demonstrating reduced anxiety and improved sexual
performance following tongkat ali feeding [37-40], with such effects thought to be due to a
restoration of normal testosterone levels. Eurycoma’s anxiolytic effects have been
demonstrated in a variety of behavioral tests, including elevated plus-maze, open field, and
anti-fighting, suggesting an equivalent anti-anxiety effect to diazepam as a positive control
[37].
Animal studies have shown that many of the effects of the extract are mediated by its
glycoprotein components [14]. The mechanism of action of the bioactive complex
polypeptides (“eurypeptides” with 36 amino acids) has been shown to activate the CYP17

enzyme (17 alpha-hydroxylase and 17,20 lyase) to enhance the metabolism of pregnenolone
and progesterone to yield more DHEA (dehydroepiandrosterone) and androstenedione,
respectively [29]. This glycoprotein water-soluble extract of Eurycoma longifolia has been
shown to deliver anti-aging and anti-stress benefits subsequent to its testosterone-balancing
effects [41,42].
Oral toxicity studies (Wistar rats) have determined the LD50 of tongkat ali root extract as
2,000 mg/kg body weight (acute) and the NOAEL (no observed adverse effect level) as
greater than 1,000 mg/kg body weight (28-day sub-acute feeding), resulting in a classification
as Category 5 (extremely safe) according to the United Nations Globally Harmonized System
of Classification and Labeling of Chemicals (GHS).
In addition to the very high safety profile demonstrated in the rodent toxicity studies, there
are no reported adverse side effects in human studies of tali supplementation. For example,
one 2-month human supplementation trial [27] of twenty healthy males (age range 38–58),
found high doses of Eurycoma longifolia extract (600 mg/day) to have no influence on blood
profiles (hemoglobin, RBC, WBC, etc.) or any deleterious effects on measures of liver or
renal function. Typical dosage recommendations, based on traditional use and on the
available scientific evidence in humans, including dieters and athletes, call for 50-200 mg/day
of a water-extracted tongkat ali root standardized to 22% eurypeptides.
Human supplementation trials
Based on a long history of traditional use and confirmation of biological activity via cell
culture and animal feeding studies, several human supplementation studies have been
conducted to evaluate the potential benefits of tongkat ali for sexual function, exercise
performance, weight loss, and vigor (mental/physical energy).
Importantly, all of the human trials have used the same water-extracted and standardized
eurycoma root for which a patent has been issued jointly to the Government of Malaysia and
the Massachusetts Institute of Technology (United States Patent #7,132,117) [29]. The patent
discloses a process whereby Eurycoma longifolia roots undergo an aqueous extraction
combined with HPLC and size-exclusion chromatography to yield a bioactive peptide
fraction (a 4300 dalton glycopeptide with 36 amino acids) that is responsible for its effects in
maintaining testosterone levels. The bioactive fraction of Eurycoma longifolia root delivers a
demonstrated ability to improve testosterone levels [41], increase muscle size and strength
[43,44], improve overall well-being [45,46], accelerate recovery from exercise [47] enhance
weight loss [48,49], reduce stress [50], and reduce symptoms of fatigue [51-53].
Based on it’s long history of traditional medicinal use as an “anti-aging” remedy and the
series of animal and human supplementation studies investigating it’s use as a physical and
mental performance aid, we undertook a study of the effects of tongkat ali root extract
supplementation in moderately stressed subjects. Our hypothesis was that tongkat ali
supplementation may influence anabolic/catabolic stress hormone balance and mood state
parameters in a group of volunteers with moderate stress levels.

Methods
All procedures, measurements, and informed consent processes were reviewed and approved
by an external third-party review board (Aspire IRB; Santee, CA).
Subjects were recruited in and around Salt Lake City, Utah via flyers asking for volunteers
with “moderate stress levels.” We screened approximately 75 subjects for moderate levels of
psychological stress. Our intention was to complete the study with 60 subjects (30 subjects
per treatment group). We used a screening survey that we have used in past studies of
stress/mood to identify individuals with moderately elevated levels of perceived stress
[19,21,47-50]. Subjects scoring 6 or greater on this screening survey indicated eligibility for
enrollment into the supplementation study (a score of 6–10 indicates moderate stress).
Sixty-four (64) subjects (32 men and 32 women) were randomized to receive tongkat ali (TA;
200 mg/day of PhystaTM, Biotropics Malaysia Berhad; 32 subjects) or look-alike placebo (PL;
32 subjects) for 4 weeks. The 4-week duration was selected as more representative of
persistent changes in mood state that may result from superior hormone balance, as opposed
to short-term changes in emotions that may be more closely linked with stressors of daily
living.
At Baseline (week 0) and Post-supplementation (week 4), we assessed Mood State and
Hormone Profile as our primary outcome measurements. Secondary measurements were
made of liver enzymes (ALT; alanine aminotransferase and AST; aspartate aminotransferase;
Alere Cholestech, Waltham, MA), body weight, and body fat percentage (Tanita; TBF-300A,
Arlington Heights, IL).
Mood State (Vigor, Depression, Anger, Confusion, Fatigue, and Anxiety) was assessed using
the validated Profile of Mood States (POMS) survey. Hormone profile (cortisol and
testosterone) was assessed in saliva samples collected at three time points during each
collection day (morning, afternoon, and evening). Saliva samples were analyzed for free
cortisol and free testosterone by enzyme immunoassay (Salimetrics; State College, PA).
Results were analyzed by one-way analysis of variance (ANOVA) with significance set at p <
0.05.
Sixty-three subjects (32 men and 31 women) completed the study, with one woman in the
supplement group lost to follow up (did not return final samples).
Results
Three subjects reported feeling unusually fatigued during the first two weeks of the study
(two subjects in the TA group and 1 subject in the placebo group). There were no other
adverse events or side effects reported.
Over the course of the supplementation period, there were no significant changes in markers
of liver function (AST/ALT), body weight or body fat percentage.
Mood state parameters showed mixed results (Figure 1), with no effect observed between
supplementation groups for indices of Depression, Vigor, or Fatigue, whereas significant

improvements were found in the TA group for Tension (−11%), Anger (−12%), and
Confusion (−15%) compared to placebo. A non-significant trend (p = .083) was found for an
improvement in overall well-being in the TA group (+3% in Global Mood State).
Figure 1 Profile of Mood States (POMS). Daily supplementation (200 mg/day for 4 weeks)
with tongkat ali (TA) resulted in significant improvements compared to placebo (PL) for
indices of Tension (−11%), Anger (−12%), and Confusion (−15%) in moderately stressed
adults (N = 63). * = p < 0.05 by ANOVA.
Hormone profile (salivary cortisol and testosterone) was significantly improved by TA
supplementation, with reduced cortisol exposure (−16%, Figure 2), increased testosterone
status (+37%, Figure 3) and overall improved cortisol:testosterone ratio (−36%) in the TA
group compared to placebo.
Figure 2 Salivary Cortisol. Salivary cortisol levels were significantly lower (−16%
compared to placebo, PL) following tongkat ali (TA) supplementation (200 mg/day for 4
weeks). * = p < 0.05 by ANOVA.
Figure 3 Salivary Testosterone. Salivary testosterone levels were significantly higher
(+37% compared to placebo, PL) following tongkat ali (TA) supplementation (200 mg/day
for 4 weeks). * = p < 0.05 by ANOVA.
Discussion
The current study found that daily supplementation with tongkat ali root extract (200 mg/day)
improves stress hormone profile (lower cortisol; higher testosterone) and certain mood state
parameters (lower tension, anger, and confusion). These findings are in agreement with
several recent supplementation trials in humans, suggesting that tongkat ali may be an
effective approach to shielding the body from the detrimental effects of chronic stress from
daily stressors, dieting for weight loss, sleep deprivation, and intense exercise training.
Previous studies have determined that Eurycoma longifolia contains a group of small peptides
referred to as “eurypeptides” that are known to have effects in improving energy status and
sex drive in studies of rodents [14-16]. The precise mechanism by which eurypeptides or
tongkat ali root extract restores normal testosterone levels is unknown, but has been
suggested as influencing the release rate of “free” testosterone from its binding hormone, sex-
hormone-binding-globulin (SHBG) [17,18].
In two recent studies of young men undergoing a weight-training regimen [43,44] tongkat ali
supplementation (100 mg/day) improved lean body mass, 1-RM strength, and arm
circumference to a significantly greater degree compared to a placebo group.
In a recent 12-week trial [46] of Eurycoma longifolia supplementation (300 mg/day), men
(30–55 years of age) showed significant improved compared to placebo in the Physical
Functioning domain of the SF-36 quality of life survey. In addition, sexual libido was
increased by 11% (week 6) and 14% (week 12) and abdominal fat mass was significantly
reduced in subjects with BMI > 25 kg/m2.

In men with low testosterone levels (average age 51 years), one month of daily
supplementation with tongkat ali extract (200 mg/day) resulted in a significant improvement
in serum testosterone levels and quality-of-life parameters [41], suggesting a role for tongkat
ali as an “adaptogen” against aging-related stress. Another study of healthy adult males
(average age 25 years), 100 mg/day of tongkat ali extract added to an intensive strength
training program (every other day for 8 weeks) resulted in significant improvements in fat-
free mass, fat mass, maximal strength (1-RM) and arm circumference compared to a placebo
group [43]. These results indicate that tongkat ali extract is able to enhance muscle mass and
strength gains, while accelerating fat loss, in healthy exercisers, and thus, may be considered
a natural ergogenic aid for athletes and dieters alike.
One study of middle-aged women (aged 45–59 years) found that twice-weekly strength
training plus 100 mg/day of Eurycoma longifolia extract for 12 weeks enhanced fat free mass
to a greater degree compared to women adhering to the same strength training program and
taking a placebo [44]. Additional studies in dieters [48-50] and athletes [47] have shown 50-
100 mg/day of tongkat ali extract to help restore normal testosterone levels in supplemented
dieters (compared to a typical drop in testosterone among non-supplemented dieters) and
supplemented athletes (compared to a typical drop in non-supplemented athletes). In one trial
of endurance cyclists [47] cortisol levels were 32% lower and testosterone levels were 16%
higher in supplemented subjects compared to placebo, indicating a more favorable
biochemical profile for promoting an “anabolic” hormone state.
For a dieter, it would be expected for cortisol to rise and testosterone to fall following several
weeks of dieting [54]. This change in hormone balance (elevated cortisol and suppressed
testosterone) is an important factor leading to the familiar “plateau” that many dieters hit
(when weight loss slows/stops) after 6–8 weeks on a weight loss regimen. By maintaining
normal testosterone levels, a dieter could expect to also maintain their muscle mass and
metabolic rate (versus a drop in both subsequent to lower testosterone levels) – and thus
continue to lose weight without plateauing.
For an athlete, the same rise in cortisol and drop in testosterone is an early signal of
“overtraining” – a syndrome characterized by reduced performance, increased injury rates,
suppressed immune system activity, increased appetite, moodiness, and weight gain [55].
Maintenance of normal cortisol/testosterone levels in eurycoma-supplemented subjects may
be able to prevent or reduce some of these overtraining symptoms as well as help the athlete
to recover faster and more completely from daily training bouts.
These results indicate that daily supplementation with a properly standardized 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.
Conclusions
A wide range of investigations, from laboratory research, to animal feeding studies, to human
supplementation trials, have confirmed the health benefits and traditional use of tongkat ali
root extract. Laboratory evidence shows that eurycoma peptides stimulate release of free
testosterone from its binding proteins and improve overall hormone profiles. More than a

dozen rodent feeding studies have demonstrated improved sex drive, balanced hormonal
profiles, and enhanced physical function. Human supplementation trials show a clear
indication of reduced fatigue, heightened energy and mood, and greater sense of well-being
in subjects consuming tongkat ali root extracts. It is important to note that the majority of
these studies, and all of the human supplementation trials, have been conducted on specific
hot-water-extracts of Eurycoma longifolia (which is the traditional Malaysian preparation)
produced using a patented extraction process to isolate and concentrate the bioactive
compounds.
In conclusion, tongkat ali, used for centuries in traditional medicine systems of Southeast
Asia for treating lethargy, low libido, depression, and fatigue, appears to have significant
potential for restoring hormone balance (cortisol/testosterone) and improving psychological
mood state in humans exposed to various modern stressors, including aging, dieting, and
exercise stress.
Competing interests
The authors have no directly competing interests, although one (AG) is an employee of a
company that manufactures tongkat ali extract, and another (MP) is an employee of a
nutrition company that uses tongkat ali as one ingredient in an anti-stress dietary supplement.
The other authors (ST and JT) conducted this study as employees of SupplementWatch,
which received funding for this trial from Biotropics Malaysia.
This study was funded by Biotropics Malaysia and conducted by SupplementWatch.
Authors' contributions
Each author contributed significantly to the successful carriage of this study. ST designed the
study and drafted the manuscript. JT coordinated the IRB approval, subject visits, and sample
inventory. AG and MP participated in the study design and coordination of subject visits. All
authors read and approved the manuscript.
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