Sports Medicine
Dehydroepiandrosterone and sport
Dehydroepiandrosterone (DHEA) is a weak androgen, but is one of the
main precursors of testosterone. Athletes use it for its androgenic
and anticatabolic effects and it has been described as a "wonder
drug", although there is little evidence to support these claims.
There are no published studies of the long term effects of taking DHEA,
particularly in the large doses used by athletes, or of its possible
interactions with other agents.
A Brian Corrigan
MJA 1999; 171: 206-208
See also Kennedy
Introduction -
Physiology -
DHEA and exercise -
Medical use -
Use by athletes -
Screening for DHEA use -
Long term effects -
Acknowledgements -
References -
Authors' details
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Introduction |
In Australia, considerable interest in the use of
dehydroepiandrosterone (DHEA) in sports has followed the positive
drug tests of two sportsmen, one for DHEA and one for its metabolite,
androstenediol. DHEA is a 19-carbon steroid, classified as an
androgen,1 albeit a weak one. It is the
major steroid hormone secreted by the adrenal glands2,3 and
circulates in two forms. One is unconjugated DHEA; the other, present
in a much higher concentration, is conjugated as its sulfate, DHEAS.
The two are readily interconvertible.4-6
DHEA is one of the main precursors in the biosynthesis of the male and
female sex hormones.1 It is formed from the
metabolism of cholesterol to pregnenolone and then to DHEA or DHEAS,
and can be converted in the tissues to the far more potent androgens
testosterone and dihydrotestosterone (Box 1).7
DHEA first burst into prominence nearly 20 years ago when, following
animal experiments, it was described as a "wonder drug"8 and "the
fountain of youth", with claims that it was an anti-aging,
anti-obesity, and anticancer drug. At that time it was available in
the United States only on prescription, but in 1985 the Food and Drug
Administration (FDA) ordered manufacturers to stop marketing DHEA
as a weight-loss product.
In 1994, following intense lobbying by the healthfood industry, an
Act of Congress allowed DHEA to be sold in the US as an over-the-counter
dietary nutritional supplement.9 The effect of this Act was to
shift the burden of proof onto the FDA to prove that a nutritional
substance was harmful. The Act also stated that labelling was not to
make any unsubstantiated health claims, but this failed to stop the
profusion of advertisements on the Internet.10 The fond belief that, if
labelled as having "no drug intent", DHEA would be used only as a food
supplement, or that it would be used only in small doses, turned out to
be just that -- a fond belief. The FDA still does not approve it for any
medical indication.9,11
In Australia, DHEA is a banned drug, and a prohibited import under the
Customs (Prohibited Imports) Regulations (Cwlth). It has no listed
medical uses, and cannot be marketed.
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Physiology |
Circulating levels of DHEA and DHEAS peak in early adulthood, then
progressively decline with age.6,12 DHEA has a short
half-life of 25 minutes; DHEAS has a half-life of some 10 hours. Most
DHEA circulates bound to albumin,13,14 with only minimal
binding to sex hormone binding globulin (SHBG) and a smaller amount
being free. In contrast, DHEAS is more strongly bound to albumin, only
a small amount is free, and none appears bound to SHBG.13 Secretion of
DHEA, but not of DHEAS, has a circadian rhythm.1,15,16 DHEAS is present at a
plasma concentration much higher than any other adrenal steroid.
Despite its abundance and rapid turnover rate, DHEA's physiological
role remains uncertain.14,17,18 A DHEA deficiency
state has never been described.19 For men or women who have
either adrenal insufficiency or hypopituitarism, although gluco-
and mineralocorticosteroid replacement is needed, 50 mg a day of DHEA
is sufficient for replacement.12,20
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DHEA and exercise | |
Four studies have been published concerning the effect of physical
exercise on DHEA levels. Two of these, involving trained sportsmen,
found exercise produced a significant rise in DHEA
levels.21,22 The third, with
patients in a cardiac rehabilitation program,23 reported no
effect. In the other,24 middle-aged women using a
treadmill had raised serum DHEA and DHEAS levels.
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Medical use |
DHEA has been described in the treatment of many disorders, including
cardiovascular disease,25 breast
cancer,26 obesity,27 and as
replacement therapy to improve the fall in DHEA levels that occurs in
aging men and women.6,28,29 These are all
controversial.
DHEA is usually available in 25 mg or 50 mg tablets, which have an
average absorption of 50% from the gut.28 It has also been used in an
injectable ester form, intramuscular prasterone enanthate 200 mg
(Gynodian Depot, Schering), and it has been given as a vaginal
pessary. As with other sports drugs, such as steroids, tablets can be
readily bought on the black market or on the Internet, but may prove to
be counterfeit.30
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Use by athletes | |
The number of athletes who use DHEA as a supplement is unknown (Box
2).31 Athletes use DHEA for
several reasons:
- as an anabolic agent to increase levels of
androgens such as androstenediol and testosterone. Its
effectiveness as an anabolic or energy-producing agent remains
unproven. Nevertheless, an anabolic effect was supported in one
study,18 when DHEA was given to
healthy young men in a dose of 1600 mg a day orally for four weeks. Fat
levels decreased and fat-free body mass increased by an average of 4.5
kg. However, in another study using better technology,32 a ninefold
increase in DHEAS levels was induced in eight healthy young men given
1600 mg a day for four weeks in a double-blind crossover study. No
effect on bodyweight, lean mass or cholesterol resulted; the authors
concluded that "DHEA is not an important regulator of energy or
protein metabolism in humans".32 There are no published
data on what happens when athletes take long term supraphysiological
doses of these agents, nor what might happen if older athletes, such as
participants in the Master's Games, used DHEA to achieve the levels
found in younger people.
- as an anticatabolic agent.33 One major proposed
mechanism of DHEA's mode of action is to counteract the catabolic
effect of corticosteroids, which may be elevated following stress
and exhaustion due to sporting events or heavy training
schedules.3 DHEA is a powerful
antiglucocorticoid33-36 and could accelerate
recovery from the stress.
- as a difficult-to-detect means to increase steroid levels. A
positive drug test for anabolic steroids is based on the testosterone
(T) to epitestosterone (E) ratio (epitestosterone is an inactive
isomer of testosterone produced in the testes). The T/E ratio is
around 1:1 in normal individuals, and it rises with exogenous steroid
administration. The International Olympic Committee (IOC) uses a
cut-off of 6:1 for drug testing; any test result above that is
considered to be a positive that requires further investigation. As
DHEA is a precursor in testosterone formation, it would increase the
concentrations of both T and E, so that the T/E ratio would remain
within the normal range. Although the T/E ratio does rise with DHEA
use, it usually does so to only a modest degree, usually remaining
below the IOC cut-off level.37 However, this is also
obviously dependent on the dose and length of time of administration,
so that, with a high enough dose, the ratio can be
increased.38 Cases of a high T/E ratio
have been known after excessive intake, but such an increase in the
ratio is more likely to occur with androstenediol than with DHEA.
- as with most other steroids, DHEA is a neurosteroid39-41 capable of
producing marked psychological effects,28,42-44 such as euphoria or
anxiety.45
|
Screening for DHEA use | |
In Australia, DHEA is an illegal drug that may not be imported,
prescribed or administered. However, it is still possible to order it
from the Internet. In early 1997, the IOC specifically added it to the
list of drugs proscribed because of its androgenic effects.
Previously, it would have been banned as "a related substance". Few
technical difficulties are associated with detecting DHEA in the
urine, but its normal range and a legal level for detection purposes
need to be established. In one report, the authors recommend a urinary
concentration threshold of 300 mg per litre of DHEA glucuronide for
drug-screening purposes.3 Similar figures have been
obtained in Australia (Dr R Kazlauskas, Director, Australian Sports
Drug Testing Laboratory, personal communication). A screening test
might need to rely on urinary ratios between DHEA and other steroids,
or else some form of carbon isotope ratio measurement might be
developed.46
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Long term effects | |
The long term effects of DHEA are not known, although it does seem to be
capable of interfering with many basic hormonal and endocrine
systems, including breast, uterine and prostate
tumours.47,48 Most of the theories
concerning its anticipated effects have been extrapolated from
epidemiological or animal studies. There have never been any
properly conducted long term clinical trials of its efficacy or side
effects in humans, and nothing is known about its interactions with
other compounds. For these reasons, it should never be used as a long
term treatment in young people such as athletes.
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Acknowledgements | |
I would like to thank Dr John Carter and Dr Michael Kennedy; the
Australian Sports Drug Agency, and the librarians at Concord
Hospital, for all their help.
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References |
- Williams JD. Textbook of endocrinology. Williams JD, Foster DW,
editors. 8th ed. Philadelphia: WB Saunders, 1992; 579-581.
-
Greenspan FS. Basic and clinical endocrinology. 3rd ed. New
Jersey: Prentice-Hall, 1991; 469-471.
-
Dehennin L, Ferry M, Lafarge P, et al. Oral administration of
dehydroepiandrosterone to healthy men: alteration of the urinary
androgen profile and consequences for the detection of abuse in sport
by gas chromatography-mass spectrometry. Steroids 1998;
63: 80-87.
-
Bird CE, Masters V, Clark AF. Dehydroepiandrosterone sulfate:
kinetics of metabolism in normal young men and women. Clin Invest
Med 1984; 7: 119-122.
-
Haning RV Jr, Carlson IH, Flood CA, et al. Metabolism of
dehydroepiandrosterone sulfate (DS) in normal women and women with
high DS concentrations. J Clin Endocrinol Metab 1991; 73:
1210-1215.
-
Herbert J. The age of dehydroepiandrosterone [editorial].
Lancet 1995; 345: 1193-1194.
-
Labrie F, Belanger A, Simard J, et al. DHEA and peripheral androgen
and estrogen formation: intracrinology. Ann N Y Acad Sci
1995; 774: 16-28.
-
Kent S. DHEA: "miracle" drug? Geriatrics 1982; 37:
157-161.
-
Skolnick AA. Scientific verdict still out on DHEA. JAMA
1996; 276: 1365-1367.
-
Kreeger KY. Researchers ponder the benefits of DHEA on many
fronts. The Scientist 1997; 11(9): 11,14.
-
Dehydroepiandrosterone (DHEA). Med Lett Drugs Ther
1996; 38: 91-92.
-
Young J, Couzinet B, Nahoul K, et al. Panhypopituitarism as a model
to study the metabolism of dehydroepiandrosterone (DHEA) in humans.
J Clin Endocrinol Metab 1997; 82: 2578-2585.
-
Longcope C. Dehydroepiandrosterone metabolism. J
Endocrinol 1996; 150 Suppl: S125-S127.
-
Ebeling P, Koivisto VA. Physiological importance of
dehydroepiandrosterone. Lancet 1994; 343: 1479-1481.
-
Liu CH, Laughlin G, Fischer U, et al. Marked attenuation of
ultradian and circadian rhythms of dehydroepiandrosterone in
postmenopausal women: evidence for a reduced 17,20-desmolase
enzymatic activity. J Clin Endocrinol Metab 1990; 71:
900-906.
-
Baulieu EE. Dehydroepiandrosterone (DHEA): a fountain of youth?
J Clin Endocrinol Metab 1996; 81: 3147-3151.
-
Nestler JE, Kahwash Z. Sex-specific action of insulin to acutely
increase the metabolic clearance rate of dehydroepiandrosterone in
humans. J Clin Invest 1994; 94: 1484-1489.
-
Nestler JE, Barlascini CO, Clore JN, et al.
Dehydroepiandrosterone reduces serum low density lipoprotein
levels and body fat but does not alter insulin sensitivity in normal
men. J Clin Endocrinol Metab 1988; 66: 57-61.
-
Regelson W, Loria R, Kalimi M. Dehydroepiandrosterone (DHEA) --
the "mother steroid". I. Immunologic action. Ann N Y Acad Sci
1994; 719: 553-563.
-
Arlt W, Justl H-G, Callies F, et al. Oral dehydroepiandrosterone
for adrenal androgen replacement: pharmacokinetics and peripheral
conversion to androgens and estrogens in young healthy females after
dexamethasone suppression. J Clin Endocrinol Metab 1998;
83: 1928-1932.
-
Keizer H, Janssen GM, Menheere P, Kranenburg G. Changes in basal
plasma testosterone, cortisol, and dehydroepiandrosterone
sulfate in previously untrained males and females preparing for a
marathon. Int J Sports Med 1989; 10 Suppl 3: S139-S145.
-
Velardo A, Pantaleoni M, Valerio L, et al. Influence of exercise on
dehydroepiandrosterone sulphate and delta 4-androstenedione
plasma levels in man. Exp Clin Endocrinol 1991; 97: 99-101.
-
Milani RV, Lavie CJ, Barbee RW, Littman AB. Lack of effect of
exercise training on dehydroepiandrosterone-sulfate. Am J Med
Sci 1995; 310: 242-246.
-
Johnson LG, Kraemer RR, Haltom R, et al. Effects of estrogen
replacement therapy on dehydroepiandrosterone,
dehydroepiandrosterone sulfate, and cortisol responses to
exercise in postmenopausal women. Fertil Steril 1997; 68:
836-843.
-
Barrett-Connor E, Goodman-Gruen D. The epidemiology of DHEAS and
cardiovascular disease. Ann N Y Acad Sci 1995; 774: 259-270.
-
Bulbrook RD, Hayward JL, Spicer CC, et al. Relation between
urinary androgen and corticoid excretion and subsequent breast
cancer. Lancet 1971; 2: 395-398.
-
Clore JN. Dehydroepiandrosterone and body fat. Obes Res
1995; 3 Suppl 4: 613S-616S.
-
Morales AJ, Nolan JJ, Nelson JC, et al. Effects of replacement dose
of dehydroepiandrosterone in men and women of advancing age. J
Clin Endocrinol Metab 1994; 78: 1360-1367.
-
Yen SSC, Morales AJ, Khorram O. Replacement of DHEA in aging men and
women. Ann N Y Acad Sci 1995; 774: 128-142.
-
Lifrak ET, Parker LN. Analysis of nonprescription capsules
purported to contain an adrenal androgen. Am J Hosp Pharm
1985; 42: 587-589.
-
Sturmi JE, Diorio DJ. Anabolic agents. Clin Sports Med
1998; 17: 261-282.
-
Welle S, Jozefowicz R, Statt M. Failure of
dehydroepiandrosterone to influence energy and protein metabolism
in humans. J Clin Endocrinol Metab 1990; 71: 1259-1264.
-
Loria RM. Antiglucocorticoid function of androstenetriol.
Psychoneuroendocrinology 1997; 22 Suppl 1: S103-S108.
-
Kalimi M, Shafagoj Y, Loria R, et al. Anti-glucocorticoid effects
of dehydroepiandrosterone (DHEA). Mol Cell Biochem 1994;
131: 99-104.
-
Regelson W, Kalimi M. Dehydroepiandrosterone (DHEA) -- the
multifunctional steroid. II. Effects on the CNS, cell
proliferation, metabolic and vascular, clinical and other effects.
Mechanism of action? Ann N Y Acad Sci 1994; 719: 564-575.
-
Fleshner M, Pugh CR, Tremblay D, et al. DHEA-S selectively impairs
contextual-fear conditioning: support for the antiglucocorticoid
hypothesis. Behav Neurosci 1997; 111: 512-527.
-
Bosy TZ, Moore KA, Poklis A. The effect of oral
dehydroepiandrosterone (DHEA) on the urine
testosterone/epitestosterone (T/E) ratio in human male
volunteers. J Anal Toxicol 1998; 22: 455-459.
-
Bowers LD. Oral dehydroepiandrosterone supplementation can
increase the testosterone/epitestosterone ratio. Clin Chem
1999; 45: 295-297.
-
Baulieu EE. Neurosteroids of the nervous system, by the nervous
system, for the nervous system. Recent Prog Horm Res 1997; 52:
1-32.
-
Khorram O. DHEA: a hormone with multiple effects. Curr Opin
Obstet Gynecol 1996; 8: 351-354.
-
Dubrovsky B. Natural steroids counteracting some actions of
putative depressogenic steroids on the central nervous system:
potential therapeutic benefits. Med Hypotheses 1997; 49:
51-55.
-
Corrigan AB. Anabolic steroids and the mind. Med J Aust
1996; 165: 222-226.
-
Miller RA. DHEA -- brass ring or red herring? [editorial]. J Am
Ger Soc 1977; 45: 1402-1403.
-
Wang C, Alexander G, Berman N, et al. Testosterone replacement
therapy improves mood in hypogonadal men -- a clinical research
center study. J Clin Endocrinol Metab 1996; 81: 3578-3583.
-
Imamura M, Prasad C. Modulation of GABA-gated chloride ion influx
in the brain by dehydroepiandrosterone and its metabolites.
Biochem Biophys Res Commun 1998; 243: 771-775.
-
Magnay J. Days numbered for testosterone cheats. Sydney
Morning Herald 1999; 16 July: 12.
-
Armsey TD, Green GA. Nutrition supplements: science vs hype.
Phys Sportsmed 1997; 25: 77-92.
-
Dorgan JF, Stanczyk FZ, Longcope C, et al. Relationship of serum
dehydroepiandrosterone (DHEA), DHEA sulfate and
5-androstene-3b,17b-diol to risk of breast cancer in
postmenopausal women. Cancer Epidemiol Biomarkers Prev
1997; 6: 177-181.
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| Authors' details |
Institute of Sports Medicine, Concord Hospital, Sydney, NSW.
A Brian Corrigan, AM, FRACP, FRCP, Consultant
Reprints will not be available from the author. Correspondence: Dr A B
Corrigan, Lookout Avenue, Dee Why, NSW 2099.
Email: abc@southernx.com.au
©MJA 1999
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| 2: DHEA use by Australian athletes
In Australia, there have been two recent instances involving footballers. In the first, a player was given DHEA for presumed chronic fatigue syndrome, although there is no medical evidence that DHEA is of benefit in this condition. At the tribunal hearing, a complicated set of legal arguments resulted in the player being let off without any penalty. However, he was only to play again if he ceased his medication,which he has done, seemingly without any problems.
In the second instance, a footballer used 50mg androstenediol capsules, allegedly because he believed that it was only a food supplement. On testing, a very high testosterone/epitestosterone ratio of 14.5 was found, and he was found guilty, and the maximum penalty imposed. |
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