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Nutritional supplements: prevalence of use and contamination with doping agents

Published online by Cambridge University Press:  14 December 2007

W Van Thuyne ,
P Van Eenoo  and
F. T Delbeke
W Van Thuyne*
Affiliation:
Doping Control Laboratory, Department of Clinical Biology, Microbiology and Immunology, Faculty of Medicine and Health Sciences, Ghent University – UGent, Technologiepark 30B, B-9052 Zwijnaarde, Belgium
P Van Eenoo
Affiliation:
Doping Control Laboratory, Department of Clinical Biology, Microbiology and Immunology, Faculty of Medicine and Health Sciences, Ghent University – UGent, Technologiepark 30B, B-9052 Zwijnaarde, Belgium
F. T Delbeke
Affiliation:
Doping Control Laboratory, Department of Clinical Biology, Microbiology and Immunology, Faculty of Medicine and Health Sciences, Ghent University – UGent, Technologiepark 30B, B-9052 Zwijnaarde, Belgium
*
*Corresponding author: Dr W. Van Thuyne, fax +32 9 331 32 99, email [email protected]
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Abstract

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Based upon recent sales numbers, nutritional supplements play a key role in the lifestyle of a substantial proportion of the population. As well as products such as vitamins or minerals, several precursors of anabolic steroids are marketed as nutritional supplements. Another group of commercially available supplements are products for weight loss based upon herbal formulations originating from Ephedra species. Apart from supplements indicating the presence of these active compounds, numerous non-hormonal nutritional supplements were found that were contaminated with non-labelled anabolic steroids. Stimulating agents other than naturally occurring analogues of ephedrine were detected. A major group using dietary supplements are sportsmen, ranging from amateur level to elite athletes. Besides the possible health risks associated with the use of dietary supplements, athletes should take care not to violate the rules of the World Anti-Doping Agency because athletes remain responsible for substances detected in their biofluids, irrespective of their origin. Several analytical methods have been developed to determine the presence of doping agents as contaminants. The present review attempts to address the issues concerning the use of nutritional supplements and the detection of doping agents as contaminants in dietary supplements.

Keywords

Nutritional supplementsDopingProhormonesStimulants
Type
Research Article
Information
Nutrition Research Reviews , Volume 19 , Issue 1 , June 2006 , pp. 147 - 158
Copyright
Copyright © The Authors 2006

References

Abourashed, EA, El-Alfy, AT, Khan, IA & Walker, L (2003) Ephedra in perspective –a current review. Phytotherapy Research 17, 703–712.CrossRefGoogle ScholarPubMed
Barkan, S, Weber, JD & Smith, E (1981) Determination of cross-contamination of the dia-stereomers ephedrine and pseudoephedrine by high-performance liquid-chromatography, thin-layer chromatography and C-13 nuclear magnetic-resonance spectroscopy. Journal of Chromatography 219, 81–88.CrossRefGoogle Scholar
Bell, A, Dorsch, KD, McCreary, DR & Hovey, R (2004) A look at nutritional supplement use in adolescents. Journal of Adolescent Health 34, 508–516.CrossRefGoogle Scholar
Bell, DG & Jacobs, I (1999) Combined caffeine and ephedrine ingestion improves run times of Canadian Forces Warrior Test. Aviation Space and Environmental Medicine 70, 325–329.Google ScholarPubMed
Bell, DG, Jacobs, I & Ellerington, K (2001) Effect of caffeine and ephedrine ingestion on anaerobic exercise performance. Medicine and Science in Sports and Exercise 33, 1399–1403.CrossRefGoogle ScholarPubMed
Bell, DG, Jacobs, I, McLellan, TM & Zamecnik, J (2000) Reducing the dose of combined caffeine and ephedrine preserves the ergogenic effect. Aviation Space and Environmental Medicine 71, 415–419.Google ScholarPubMed
Bell, DG, Jacobs, I & Zamecnik, J (1998) Effects of caffeine, ephedrine and their combination on time to exhaustion during high-intensity exercise. European Journal of Applied Physiology and Occupational Physiology 77, 427–433.CrossRefGoogle ScholarPubMed
Bents, RT, Tokish, JM & Goldberg, L (2004) Ephedrine, pseudoephedrine, and amphetamine prevalence in college hockey players–most report performance-enhancing use. Physician and Sportsmedicine 32, 30–34.CrossRefGoogle ScholarPubMed
Benzi, G (2000) Is there a rationale for the use of creatine either as nutritional supplementation or drug administration in humans participating in a sport? Pharmacological Research 41, 255–264.CrossRefGoogle Scholar
Beshgetoor, D & Nichols, JF (2003) Dietary intake and supplement use in female master cyclists and runners. International Journal of Sport Nutrition and Exercise Metabolism 13, 166–172.CrossRefGoogle Scholar
Betz, JM, Gay, ML, Mossoba, MM, Adams, S & Portz, BS (1997) Chiral gas chromatographic determination of ephedrine-type alkaloids in dietary supplements containing Ma Huang. Journal of AOAC International 80, 303–315.CrossRefGoogle ScholarPubMed
Boozer, CN, Daly, PA, Homel, P, Solomon, JL, Blanchard, D, Nasser, JA, Strauss, R & Meredith, T (2002) Herbal ephedra/caffeine for weight loss: a 6-month randomized safety and efficacy trial. International Journal of Obesity 26, 593–604.CrossRefGoogle ScholarPubMed
Broeder, CE (2003) Oral andro-related prohormone supplementation: do the potential risks outweigh the benefits? Canadian Journal of Applied Physiology 28, 102–116.CrossRefGoogle ScholarPubMed
Broeder, CE, Quindry, J, Brittingham, K, Panton, L, Thomson, J, Appakondu, S, Breuel, K, Byrd, R, Douglas, J, Earnest, C, et al. (2000) The andro project–physiological and hormonal influences of androstenedione supplementation in men 35 to 65 years old participating in a high-intensity resistance training program. Archives of Internal Medicine 160, 3093–3104.CrossRefGoogle Scholar
Brown, GA, Vukovich, MD, Reifenrath, TA, Uhl, NL, Parsons, KA, Sharp, RL & King, DS (2000) Effects of anabolic precursors on serum testosterone concentrations and adaptations to resistance training in young men. International Journal of Sport Nutrition and Exercise Metabolism 10, 340–359.CrossRefGoogle ScholarPubMed
Canter, PH & Ernst, E (2004) Herbal supplement use by persons aged over 50 years in Britain–frequently used herbs, concomitant use of herbs, nutritional supplements and prescription drugs, rate of informing doctors and potential for negative interactions. Drugs and Aging 21, 597–605.CrossRefGoogle ScholarPubMed
Catlin, DH, Leder, BZ, Ahrens, B, Starcevic, B, Hatton, CK, Green, GA & Finkelstein, JS (2000) Trace contamination of over-the-counter androstenedione and positive urine test results for a nandrolone metabolite. Journal of the American Medical Association 284, 2618–2621.CrossRefGoogle Scholar
Chen, KK & Schmidt, CF (1926) The action and clinical use of ephedrine. Journal of the American Pharmaceutical Association 87, 836–842.Google Scholar
Chester, N, Reilly, T & Mottram, DR (2003) Physiological, subjective and performance effects of pseudoephedrine and phenylpropanolamine during endurance running exercise. International Journal of Sports Medicine 24, 3–8.CrossRefGoogle ScholarPubMed
Chu, KS, Doherty, TJ, Parise, G, Milheiro, JS & Tarnopolsky, MA (2002) A moderate dose of pseudoephedrine does not alter muscle contraction strength or anaerobic power. Clinical Journal of Sports Medicine 12, 387–390.CrossRefGoogle Scholar
Corrigan, B & Kazlauskas, R (2003) Medication use in athletes selected for doping control at the Sydney Olympics (2000). Clinical Journal of Sport Medicine 13, 33–40.CrossRefGoogle Scholar
Coutts, RT, Dawe, R, Jones, GR, Liu, SF & Midha, KK (1980) Analysis of perfluoroacyl derivatives of ephedrine, pseudoephedrine and analogues by gas-chromatography and mass-spectrometry. 1. Trifluoroacetyl derivatives. Journal of Chromatography 190, 53–65.CrossRefGoogle Scholar
Davies, AM (1997) Survey of caffeine and other methylxanthines in energy drinks and other caffeine-containing products. Food Surveillance 103, 1–18.Google Scholar
De Cock, KJS, Delbeke, FT, Van Eenoo, P, Desmet, N, Roels, K & De Backer, P (2001) Detection and determination of anabolic steroids in nutritional supplements. Journal of Pharmaceutical and Biomedical Analysis 25, 843–852.CrossRefGoogle ScholarPubMed
Delbeke, FT (2001) Nutritional supplements and doping. In Biomedical Side Effects of Doping, pp. 155–161 [Peters, C, Schulz, T and Michna, H, editors]. Cologne: Sport and Buch Strauβ.Google Scholar
Delbeke, FT, Van Eenoo, P, Van Thuyne, W, Desmet, N (2002) Prohormones and sport. Journal of Steroid Biochemistry and Molecular Biology 83, 245–251.CrossRefGoogle ScholarPubMed
Doherty, M (1998) The effects of caffeine on the maximal accumulated oxygen deficit and short-term running performance. International Journal of Sport Nutrition 8, 95–104.CrossRefGoogle Scholar
Dutt, MC & Poh, TT (1981) Identification of basic drugs by the thin-layer chromatographic profiles of their ninhydrin complexes. Journal of Chromatography 206, 267–277.CrossRefGoogle ScholarPubMed
Elsohly, HN, Stanford, DF, Jones, AB, Elsohly, MA, Snyder, H & Pedersen, C (1988) Gas-chromatographic mass-spectrometric analysis of morphine and codeine in human urine of poppy seed eaters. Journal of Forensic Sciences 33, 347–356.CrossRefGoogle ScholarPubMed
Engelhardt, M, Neumann, G, Berbalk, A & Reuter, I (1998) Creatine supplementation in endurance sports. Medicine and Science in Sports and Exercise 30, 1123–1129.CrossRefGoogle ScholarPubMed
Flurer, CL, Lin, LA, Satzger, RD & Wolnik, KA (1995) Determination of ephedrine compounds in nutritional supplements by cyclodextrin-modified capillary electrophoresis. Journal of Chromatography 669B, 133–139.CrossRefGoogle Scholar
Food and Drug Administration (1994) Dietary Supplement Health and Education Act of 1994, Public Law 103–417, 103rd Congress, 2nd session, S784. Accessed 25 01 2005. http://www.fda.gov/opacom/laws/dshea.htmlGoogle Scholar
Food and Drug Administration (2004) Center for Food Safety and Applied Nutritional. Dietary Supplements: ephedrine alkaloids. Accessed 10 01 2005. http://www.cfsan.fda.gov/~dms.ds-ephed.htmlGoogle Scholar
Gal, J (1984) Resolution of the enantiomers of ephedrine, norephedrine and pseudoephedrine by high-performance liquid-chromatography. Journal of Chromatography 307, 220–223.CrossRefGoogle Scholar
Geisendorfer, T & Gmeiner, G (2003) Analysis of nutritional supplements using gel-permeation as clean up step. In Recent Advances in Doping Analysis, pp. 373–376 [Schänzer, W, Geyer, H, Gotzmann, A and Mareck, u, editors]. Cologne: Sport and Buch Strauß.Google Scholar
Geyer, H, Bredehöft, M, Mareck, U, Parr, MK & Schänzer, W (2002) Hoge dosen des anabolikums metandienon in nahrungsergänzungsmitteln gefunden (High doses of the anabolic steroid methandienone found in nutritional supplements). Deutsche Apotheker Zeitung 142, 50.Google Scholar
Geyer, H, Mareck-Engelke, U, Reinhart, U, Thevis, M & Schänzer, W (2000) Positive Dopingfälle mit Norandrosteron durch Verunreinigte Nahrungsergänzungsmittel (Positive doping cases with norandrosterone after application of contaminated nutritional supplements). Deutsche Zeitschrift für Sportmedizin 51, 378–382.Google Scholar
Geyer, H, Parr, MK, Mareck, U, Reinhart, U, Schrader, Y & Schänzer, W (2004) Analysis of non-hormonal nutritional supplements for anabolic-androgenic steroids–results of an international study. International Journal of Sports Medicine 25, 124–129.Google ScholarPubMed
Gill, ND, Shield, A, Blazevich, AJ, Zhou, S & Weatherby, RP (2000) Muscular and cardiorespiratory effects of pseudoephedrine in human athletes. British Journal of Clinical Pharmacology 50, 205–213.CrossRefGoogle ScholarPubMed
Gillies, H, Derman, WE, Noakes, TD, Smith, P, Evans, A & Gabriels, G (1996) Pseudoephedrine is without ergogenic effects during prolonged exercise. Journal of Applied Physiology 81, 2611–2617.CrossRefGoogle ScholarPubMed
Gmeiner, G (2002) Methandienon in sportnahrung (Methandienone in sports nutrition). Osterreichische Journal fur Sportmedizin 2, 33–34.Google Scholar
Graham, TE, Hibbert, E & Sathasivam, P (1998) Metabolic and exercise endurance effects of coffee and caffeine ingestion. Journal of Applied Physiology 85, 883–889.CrossRefGoogle ScholarPubMed
Green, GA, Catlin, TH & Starcevic, B (2001) Analysis of over-the-counter dietary supplements. Clinical Journal of Sport Medicine 11, 254–259.CrossRefGoogle ScholarPubMed
Gurley, BJ, Gardner, SF & Hubbard, MA (2000) Content versus label claims in Ephedra-containing dietary supplements. American Journal of Health-System Pharmacy 57, 963–969.CrossRefGoogle ScholarPubMed
Gurley, BJ, Wang, P & Gardner, SF (1998) Ephedrine-type alkaloid content of nutritional supplements containing Ephedra sinica (Ma-Huang) as determined by high performance liquid chromatography. Journal of Pharmaceutical Sciences 87, 1547–1553.CrossRefGoogle ScholarPubMed
Habscheid, W, Abele, U & Dahm, HH (1999) Anabolic steroids as a cause of severe cholestasis and renal failure in a body builder. Deutsche Medizinische Wochenschrift 124, 1029–1032.CrossRefGoogle Scholar
Haller, CA & Benowitz, NL (2000) Adverse cardiovascular and central nervous system events associated with dietary supplements containing Ephedra alkaloids. New England Journal of Medicine 343, 1833–1838.CrossRefGoogle ScholarPubMed
Haller, CA, Duan, MJ, Benowitz, NL & Jacob, P (2004 a) Concentrations of Ephedra alkaloids and caffeine in commercial dietary supplements. Journal of Analytical Toxicology 28, 145–151.CrossRefGoogle ScholarPubMed
Haller, CA, Jacob, P & Benowitz, NL (2004 b) Enhanced stimulant and metabolic effects of combined ephedrine and caffeine. Clinical Pharmacology and Therapeutics 75, 259–273.CrossRefGoogle ScholarPubMed
Hansen, LB (2001) A stable gas chromatography-mass spectrometry analysis system to characterize Ma Huang products found in health foods and supplements. Journal of Pharmaceutical Sciences 90, 943–948.CrossRefGoogle ScholarPubMed
Hayes, LW, Krasselt, WG & Mueggler, PA (1987) Concentrations of morphine and codeine in serum and urine after ingestion of poppy seeds. Clinical Chemistry 33, 806–808.CrossRefGoogle ScholarPubMed
Hioki, C, Yoshimoto, K & Yoshida, T (2004) Efficacy of Bofu-tsusho-san, an oriental herbal medicine, in obese Japanese women with impaired glucose tolerance. Clinical and Experimental Pharmacology and Physiology 31, 614–619.CrossRefGoogle ScholarPubMed
Hodges, ANH, Lynn, BM, Bula, JE, Donaldson, MG, Dagenais, MO & McKenzie, DC (2003) Effects of pseudoephedrine on maximal cycling power and submaximal cycling efficiency. Medicine and Science in Sports and Exercise 35, 1316–1319.CrossRefGoogle ScholarPubMed
Hurlbut, JA, Carr, JR, Singleton, ER, Faul, KC, Madson, MR, Storey, JM & Thomas, TL (1998) Solid-phase extraction cleanup and liquid chromatography with ultraviolet detection of ephedrine alkaloids in herbal products. Journal of AOAC International 81, 1121–1127.CrossRefGoogle ScholarPubMed
Imaz, C, Carreras, D, Navajas, R, Rodriguez, C, Rodriguez, AF, Maynar, J & Cortes, R (1993) Determination of ephedrines in urine by high-performance liquid-chromatography. Journal of Chromatography 631, 201–205.CrossRefGoogle Scholar
Imaz, C, Navajas, R, Carreras, D, Rodriguez, C & Rodriguez, AF (2000) Comparison of various reversed-phase columns for the simultaneous determination of ephedrines in urine by high-performance liquid chromatography. Journal of Chromatography 870A 23–28.CrossRefGoogle Scholar
Jacob, P, Haller, CA, Duan, MJ, Yu, L, Peng, M & Benowitz, NL (2004) Determination of Ephedra alkaloid and caffeine concentrations in dietary supplements and biological fluids. Journal of Analytical Toxicology 28, 152–159.CrossRefGoogle ScholarPubMed
Jacobs, I, Pasternak, H & Bell, DG (2003) Effects of ephedrine, caffeine, and their combination on muscular endurance. Medicine and Science in Sports and Exercise 35, 987–994.CrossRefGoogle ScholarPubMed
Kamber, M, Baume, N, Saugy, M & Rivier, L (2001) Nutritional supplements as a source for positive doping cases? International Journal of Sport Nutrition and Exercise Metabolism 11, 258–263.CrossRefGoogle ScholarPubMed
Konig, WA & Ernst, K (1983) Application of enantioselective capillary gas-chromatography to the analysis of chiral pharmaceuticals. Journal of Chromatography 280, 135–141.CrossRefGoogle Scholar
Kovacs, EMR, Stegen, JHCH & Brouns, F (1998) Effect of caffeinated drinks on substrate metabolism, caffeine excretion, and performance. Journal of Applied Physiology 85, 709–715.CrossRefGoogle ScholarPubMed
Kreider, RB (1999) Dietary supplements and the promotion of muscle growth with resistance exercise. Sports Medicine 27, 97–110.CrossRefGoogle Scholar
Leder, BZ, Longcope, C, Catlin, DH, Ahrens, B, Schoenfeld, DA & Finkelstein, JS (2000) Oral androstenedione administration and serum testosterone concentrations in young men. Journal of the American Medical Association 283, 779–782.CrossRefGoogle ScholarPubMed
Li, HX, Ding, MY, Lv, K & Yu, JY (2002) Simultaneous separation and determination of ephedrine alkaloids and tetramethylpyrazine in Ephedra sinica Stapf by HPLC. Journal of Liquid Chromatography and Related Technologies 25, 313–320.CrossRefGoogle Scholar
Lo, DST & Chua, TH (1992) Poppy seeds–implications of consumption. Medicine Science and the Law 32, 296–302.CrossRefGoogle ScholarPubMed
Macintosh, BR & Wright, BM (1995) Caffeine ingestion and performance of a 1,500-meter swim. Canadian Journal of Applied Physiology 20, 168–177.CrossRefGoogle ScholarPubMed
Manore, MM, Barr, SI & Butterfield, GE (2000) Position of dietitians of Canada, the American Dietetic Association, and the American College of Sports Medicine: nutrition and athletic performance. Canadian Journal of Dietetic Practice and Research 61, 176–192.Google Scholar
Maughan, R (2002) The scope of nutritional supplement use in sport. In Health and Doping Risks of Nutritional Supplements and Social Drugs, pp. 7–9 [Schänzer, W, Geyer, H, Gotzmann, A and Mareck-Engelke, U, editors]. Cologne: Sport and Buch Strauß.Google Scholar
Maughan, RJ, King, DS & Lea, T (2004) Dietary supplements. Journal of Sport Sciences 22, 95–113.CrossRefGoogle ScholarPubMed
Meadway, C, George, S & Braithwaite, R (1998) Opiate concentrations following the ingestion of poppy seed products–evidence for ‘the poppy seed defence’. Forensic Science International 96, 29–38.CrossRefGoogle ScholarPubMed
Morrison, LJ, Gizis, F & Shorter, B (2004) Prevalent use of dietary supplements among people who exercise at a commercial gym. International Journal of Sport Nutrition and Exercise Metabolism 14, 481–492.CrossRefGoogle Scholar
Mottram, DR & George, AJ (2000) Anabolic steroids. Baillière's Best Practice and Research. Clinical Endocrinology and Metabolism 14, 55–69.CrossRefGoogle ScholarPubMed
Mujika, I, Chatard, J, Lacoste, L, Barale, F & Geyssant, A (1996) Creatine supplementation does not improve sprint performance in competitive swimmers. Medicine and Science in Sports and Exercise 28, 1435–1441.CrossRefGoogle Scholar
Müller, RK, Müller-Platz, C (2001) Aggression and anabolic steroid hormones: do anabolic androgenic steroids enhance aggressiveness? In Biomedical Side Effects of Doping, pp. 107–114 [Peters, C, Schulz, T and Michna, H, editors]. Cologne: Sport and Buch Strauß.Google Scholar
Nieman, DC, Gates, JR, Butler, JV, Dietrich, SJ & Lutz, RD (1989) Supplementation patterns in marathon runners. Journal of the American Dietetic Association 89, 1615–1619.CrossRefGoogle ScholarPubMed
Okamura, N, Miki, H, Harada, T, Yamashita, S, Masaoka, Y, Nakamoto, Y, Tsuguma, M, Yoshitomi, H & Yagi, A (1999) Simultaneous determination of ephedrine, pseudoephedrine, norephedrine and methylephedrine in Kampo medicines by high-performance liquid chromatography. Journal of Pharmaceutical and Biomedical Analysis 20, 363–372.CrossRefGoogle ScholarPubMed
Parr, MK, Geyer, H, Reinhart, U & Schanzer, W (2004) Analytical strategies for the detection of non-labelled anabolic androgenic steroids in nutritional supplements. Food Additives and Contaminants 21, 632–640.CrossRefGoogle ScholarPubMed
Parr, MK, Geyer, H, Sigmund, G, Köhler, K & Schänzer, W (2003) Screening of nutritional supplements for stimulants and other drugs. In Recent Advances in Doping Analysis, pp. 67–75 [Schänzer, H, Geyer, H, Gotzmann, A and Mareck, u, editors]. Cologne: Sport and Buch Strauß.Google Scholar
Parssinen, M & Seppala, T (2002) Steroid use and long-term health risks in former athletes. Sports Medicine 32, 83–94.CrossRefGoogle ScholarPubMed
Perko, M, Bartee, RT, Dunn, MS, Wang, MQ & Eddy, J (2000) Giving new meaning to the term “taking one for the team”: influences on the use/non-use of dietary supplements among adolescent athletes. American Journal of Health Studies 16, 99–106.Google Scholar
Powers, ME (2001) Ephedra and its application to sport performance: another concern for the athletic trainer? Journal of Athletic Training 36, 420–424.Google ScholarPubMed
Rasmussen, BB, Volpi, E, Gore, DC & Wolfe, RR (2000) Androstenedione does not stimulate muscle protein anabolism in young healthy men. Journal of Clinical Endocrinology and Metabolism 85, 55–59.Google Scholar
Roman, MC & Walther, HJ (2004) Determination of ephedrine alkaloids in botanicals and dietary supplements by HPLC-UV: collaborative study. Journal of AOAC International 87, 1–14.CrossRefGoogle ScholarPubMed
Ronsen, O, Sundgot-Borgen, J & Maehlum, S (1999) Supplement use and nutritional habits in Norwegian elite athletes. Scandinavian Journal of Medicine and Science in Sports 9, 28–35.CrossRefGoogle ScholarPubMed
Ros, JJW, Pelders, MG & De Smet, PAGM (1999) A case of positive doping associated with a botanical food supplement. Pharmacy World and Science 21, 44–46.CrossRefGoogle ScholarPubMed
Schroder, H, Navarro, E, Mora, J, Seco, J, Torregrosa, JM & Tramullas, A (2002) The type, amount, frequency and timing of dietary supplement use by elite players in the First Spanish Basketball League. Journal of Sports Sciences 20, 353–358.CrossRefGoogle ScholarPubMed
Schröder, U (2002) Health effects of nutritional supplements. In Health and Doping Risks of Nutritional Supplements and Social Drugs, pp. 11–15 [Schä;nzer, W, Delbeke, FT, Deligiannis, A, Gmeiner, G, Maughan, R and Mester, J, editors]. Cologne: Sport and Buch StraußGoogle Scholar
Schwenk, TL & Costley, CD (2002) When food becomes a drug: nonanabolic nutritional supplement use in athletes. American Journal of Sports Medicine 30, 907–916.CrossRefGoogle ScholarPubMed
Sekera, MH, Ahrens, BD, Chang, YC, Starcevic, B, Georgakopoulos, C & Catlin, DH (2005) Another designer steroid: discovery, synthesis, and detection of ‘madol’ in urine. Rapid Communications in Mass Spectrometry 19, 781–784.CrossRefGoogle ScholarPubMed
Selavka, CM (1991) Poppy seed ingestion as a contributing factor to opiate-positive urinalysis results–the Pacific perspective. Journal of Forensic Sciences 36, 685–696.CrossRefGoogle ScholarPubMed
Shekelle, PG, Hardy, ML, Morton, SC, Maglione, M, Mojica, WA, Suttorp, MJ, Rhodes, SL, Jungvig, L & Gagne, J (2003) Efficacy and safety of Ephedra and ephedrine for weight loss and athletic performance–a meta-analysis. Journal of the American Medical Association 289, 1537–1545.CrossRefGoogle Scholar
Sinclair, CJD & Geiger, JD (2000) Caffeine use in sports–a pharmacological review. Journal of Sports Medicine and Physical Fitness 40, 71–79.Google Scholar
Sobal, J & Marquart, LF (1994 a) Vitamin mineral supplement use among athletes–a review of the literature. International Journal of Sport Nutrition 4, 320–334.CrossRefGoogle ScholarPubMed
Sobal, J & Marquart, LF (1994 b) Vitamin mineral supplement use among high-school athletes. Adolescence 29, 835–843.Google ScholarPubMed
Sundgot-Borgen, J, Berglund, B & Torstveit, MK (2003) Nutritional supplements in Norwegian elite athletes–impact of international ranking and advisors. Scandinavian Journal of Medicine and Science in Sports 13, 138–144.CrossRefGoogle ScholarPubMed
Talalay, P (2001) The importance of using scientific principles in the development of medicinal agents from plants. Academic Medicine 76, 238–247.CrossRefGoogle ScholarPubMed
Trujillo, WA & Sorenson, WR (2003) Determination of ephedrine alkaloids in dietary supplements and botanicals by liquid chromatography/tandem mass spectrometry: collaborative study. Journal of AOAC International 86, 657–668.CrossRefGoogle ScholarPubMed
Uralets, VP & Gillette, PA (1999) Over-the-counter anabolic steroids 3-androsten-3,17-dione; 4-androsten-3 beta,17 beta-diol; and 19-nor-4-androsten-3,17-dione: excretion studies in men. Journal of Analytical Toxicology 23, 357–366.CrossRefGoogle Scholar
Uralets, VP & Gillette, PA (2000) Over-the-counter delta(5) anabolic steroids 5-androsten-3,17-dione; 5-androsten-3 beta,17 beta-diol; dehydroepiandrosterone; and 19-nor-5-androsten-3,17-dione: excretion studies in men. Journal of Analytical Toxicology 24, 188–193.CrossRefGoogle Scholar
Vandermerwe, PJ, Brown, LW & Hendrikz, SE (1994) Simultaneous quantification of ephedrines in urine by high performance liquid-chromatography. Journal of Chromatography 661B, 357–361.CrossRefGoogle Scholar
Vandermerwe, PJ & Hendrikz, SE (1995) Identification of ephedrines as their carbon-disulfide derivatives. Journal of Chromatography 663B, 160–166.CrossRefGoogle Scholar
Van Eenoo, P, Delbeke, FT, Desmet, N & De Backer, P (1998) Excretion studies with 4-androstene-3,17-dione. In Recent Advances in Doping Analysis, pp. 171–180 [Schänzer, W, Geyer, H, Gotzmann, A and Mareck-Engelke, U, editors]. Cologne: Sport and Buch Strauβ.Google Scholar
Van Eenoo, P, Delbeke, FT, Desmet, N & De Backer, P (2000) Excretion studies with Tribulus terrestris. In Recent Advances in Doping Analysis, pp. 13–22 [Schänzer, W, Geyer, H, Gotzmann, A and Mareck-Engelke, U, editors]. Cologne: Sport and Buch Strauβ.Google Scholar
Van Eenoo, P, Delbeke, FT, Roels, K & De Backer, P (2001) Simultaneous quantitation of ephedrines in urine by gas chromatography-nitrogen-phosphorus detection for doping control purposes. Journal of Chromatography 760B, 255–261.CrossRefGoogle Scholar
Van Thuyne, W & Delbeke, FT (2004) Validation of a GC-MS screening method for anabolizing agents in solid nutritional supplements. Biomedical Chromatography 18, 155–159.CrossRefGoogle ScholarPubMed
Van Thuyne, W & Delbeke, FT (2005) Validation of a GC-MS screening method for anabolizing agents in aqueous nutritional supplements. Journal of Chromatographic Science 43, 2–6.CrossRefGoogle Scholar
Van Thuyne, W & Van Eenoo, P & Delbeke, FT (2003) Urinary concentrations of morphine after the administration of herbal teas containing Papaveris fructus in relation to doping analysis. Journal of Chromatography 785B, 245–251.Google Scholar
Van Thuyne, W, Van Eenoo, P, Mikulcíková, P & Deventer, K, Delbeke, FT (2005) Detection of androst-4-ene-3,6,17-trione (6-OXO®) and its metabolites in urine by gas chromatography-mass spectrometry in relation to doping analysis. Biomedical Chromatography 19, 689–695.CrossRefGoogle ScholarPubMed
Volek, JS, Kraemer, WJ, Bush, JA, Boetes, M, Incledon, T, Clark, KL & Lynch, JM (1997) Creatine supplementation enhances muscular performance during high-intensity resistance exercise. Journal of the American Dietetic Association 97, 765–770.CrossRefGoogle Scholar
Wadler, GI & Hainline, B (1989) Anabolic steroids: adverse effects. In Drugs and the Athlete, pp. 55–66 [Ryan, AJ, editor]. Philadelphia, PA: FA Davis Company.Google Scholar
Wainer, IW, Doyle, TD, Fry, FS & Hamidzadeh, Z (1986) Chiral recognition model for the resolution of ephedrine and related alpha-aminoalcohol, beta-aminoalcohol as enantiomeric oxazolidine derivatives. Journal of Chromatography 355, 149–156.CrossRefGoogle Scholar
Wiedemer, B & Thrall, C (2004) Analysis of Ephedra alkaloids by gas chromatography. LCGC North America. The Application Notebook Advertising Supplement, 06 2004. p. 43.Google Scholar
World Anti-Doping Agency (2004) The World Anti-Doping Code. The 2004 Prohibited List International Standard. Montreal: WADA.Google Scholar
Ziegler, PJ, Nelson, JA & Jonnalagadda, SS (2003) Use of dietary supplements by elite figure skaters. International Journal of Sport Nutrition and Exercise Metabolism 13, 266–276.CrossRefGoogle ScholarPubMed
Zorpette, G (1999) The mystery of muscle. Scientific American 10, 48–55.Google Scholar