Influence of energy drink ingredients on mood and cognitive performance

Nutrition Reviews

Volumn 72, Issue S1, 2014, Pages 48-59

  Childs, Emma ^a  

^a The University of Chicago   (United States)

Author keywords

Attention; Cognition; Energy drink; Memory; Mood

Indexed keywords

5 HYDROXYTRYPTOPHAN; AMINO ACID; CAFFEINE; CARBOHYDRATE; CARNITINE; CITICOLINE; CREATINE; FLAVONOID; GLUCOSE; GREEN TEA EXTRACT; HERBACEOUS AGENT; KAEMPFEROL; METHYLXANTHINE; MINERAL; PHENYLALANINE; PSYCHOSTIMULANT AGENT; QUERCETIN; SAPONIN; TANNIN DERIVATIVE; TAURINE; THEANINE; THEOBROMINE; THEOPHYLLINE; TRYPTOPHAN; TYROSINE; VITAMIN; YOHIMBINE; CENTRAL STIMULANT AGENT; PERFORMANCE ENHANCING SUBSTANCE;

ALCOHOLISM; ALERTNESS; ARTICLE; BRAIN FUNCTION; COGNITION; DIET SUPPLEMENTATION; ENERGY DRINK; EXECUTIVE FUNCTION; GINSENG; GUARANA; HUMAN; HYPERICUM PERFORATUM; MEMORY; MOOD; NORMAL HUMAN; RISK; SLEEP; TEA; AFFECT; ATTENTION; DIETARY SUPPLEMENT; DRUG EFFECTS;

AFFECT; ATTENTION; CAFFEINE; CENTRAL NERVOUS SYSTEM STIMULANTS; COGNITION; DIETARY SUPPLEMENTS; ENERGY DRINKS; HUMANS; PERFORMANCE-ENHANCING SUBSTANCES; SLEEP;

EID: 84907848496     PISSN: 00296643     EISSN: 17534887     Source Type: Journal    
DOI: 10.1111/nure.12148     Document Type: Article

References (177)

1. Alford C, Cox H, Wescott R. The effects of Red Bull energy drink on human performance and mood. Amino Acids. 2001;21:139-150.
2. Geiß KR, Jester I, Falke W, etal. The effect of a taurine-containing drink on performance in 10 endurance-athletes. Amino Acids. 1994;7:45-56.
3. Kennedy DO, Scholey AB. A glucose-caffeine "energy drink" ameliorates subjective and performance deficits during prolonged cognitive demand. Appetite. 2004;42:331-333.
4. Scholey AB, Kennedy DO. Cognitive and physiological effects of an "energy drink": an evaluation of the whole drink and of glucose, caffeine and herbal flavouring fractions. Psychopharmacology. 2004;176:320-330.
5. Seidl R, Peyrl A, Nicham R, etal. A taurine and caffeine-containing drink stimulates cognitive performance and well-being. Amino Acids. 2000;19:635-642.
6. Smit HJ, Cotton JR, Hughes SC, etal. Mood and cognitive performance effects of "energy" drink constituents: caffeine, glucose and carbonation. Nutr Neurosci. 2004;7:127-139.
7. Warburton DM, Bersellini E, Sweeney E. An evaluation of a caffeinated taurine drink on mood, memory and information processing in healthy volunteers without caffeine abstinence. Psychopharmacology. 2001;158:322-328.
8. Smith A. Effects of caffeine on human behavior. Food Chem Toxicol. 2002;40:1243-1255.
9. Seifert SM, Seifert SA, Schaechter JL, etal. An analysis of energy-drink toxicity in the National Poison Data System. Clin Toxicol (Phila). 2013;51:566-574.
10. Adan A, Serra-Grabulosa JM. Effects of caffeine and glucose, alone and combined, on cognitive performance. Hum Psychopharmacol. 2010;25:310-317.
11. Giles GE, Mahoney CR, Brunye TT, etal. Differential cognitive effects of energy drink ingredients: caffeine, taurine, and glucose. Pharmacol Biochem Behav. 2012;102:569-577.
12. Maridakis V, O'Connor PJ, Tomporowski PD. Sensitivity to change in cognitive performance and mood measures of energy and fatigue in response to morning caffeine alone or in combination with carbohydrate. Int J Neurosci. 2009;119:1239-1258.
13. Serra-Grabulosa JM, Adan A, Falcon C, etal. Glucose and caffeine effects on sustained attention: an exploratory fMRI study. Hum Psychopharmacol. 2010;25:543-552.
14. Young HA, Benton D. Caffeine can decrease subjective energy depending on the vehicle with which it is consumed and when it is measured. Psychopharmacology. 2013;228:243-254.
15. Peacock A, Martin FH, Carr A. Energy drink ingredients. Contribution of caffeine and taurine to performance outcomes. Appetite. 2013;64:1-4.
16. Aggarwal R, Mishra A, Crochet P, etal. Effect of caffeine and taurine on simulated laparoscopy performed following sleep deprivation. Br J Surg. 2011;98:1666-1672.
17. Rogers PJ, Smith JE, Heatherley SV, etal. Time for tea: mood, blood pressure and cognitive performance effects of caffeine and theanine administered alone and together. Psychopharmacology. 2008;195:569-577.
18. Haskell CF, Kennedy DO, Milne AL, etal. The effects of L-theanine, caffeine and their combination on cognition and mood. Biol Psychol. 2008;77:113-122.
19. L-theanine and caffeine in combination affect human cognition as evidenced by oscillatory alpha-band activity and attention task performance. J Nutr. 2008;138:1572S-1577S.
20. Foxe JJ, Morie KP, Laud PJ, etal. Assessing the effects of caffeine and theanine on the maintenance of vigilance during a sustained attention task. Neuropharmacology. 2012;62:2320-2327.
21. Kennedy DO, Haskell CF, Wesnes KA, etal. Improved cognitive performance in human volunteers following administration of guarana (Paullinia cupana) extract: comparison and interaction with Panax ginseng. Pharmacol Biochem Behav. 2004;79:401-411.
22. Benton D. Carbohydrate ingestion, blood glucose and mood. Neurosci Biobehav Rev. 2002;26:293-308.
23. Gorby HE, Brownawell AM, Falk MC. Do specific dietary constituents and supplements affect mental energy? Review of the evidence. Nutr Rev. 2010;68:697-718.
24. Pizziol A, Tikhonoff V, Paleari CD, etal. Effects of caffeine on glucose tolerance: a placebo-controlled study. Eur J Clin Nutr. 1998;52:846-849.
25. Graham TE, Sathasivam P, Rowland M, etal. Caffeine ingestion elevates plasma insulin response in humans during an oral glucose tolerance test. Can J Physiol Pharmacol. 2001;79:559-565.
26. Gomez-Ramirez M, Higgins BA, Rycroft JA, etal. The deployment of intersensory selective attention: a high-density electrical mapping study of the effects of theanine. Clin Neuropharmacol. 2007;30:25-38.
27. L-theanine on alpha-band oscillatory brain activity during a visuo-spatial attention task. Brain Topogr. 2009;22:44-51.
28. L-Theanine reduces psychological and physiological stress responses. Biol Psychol. 2007;74:39-45.
29. L-theanine in comparison with alprazolam on anticipatory anxiety in humans. Hum Psychopharmacol. 2004;19:457-465.
30. L-theanine, a natural constituent in tea, and its effect on mental state. Asia Pac J Clin Nutr. 2008;17(Suppl 1):167-168.
31. D'Angelo L, Grimaldi R, Caravaggi M, etal. A double-blind, placebo-controlled clinical study on the effect of a standardized ginseng extract on psychomotor performance in healthy volunteers. J Ethnopharmacol. 1986;16:15-22.
32. Kennedy DO, Scholey AB, Wesnes KA. Dose dependent changes in cognitive performance and mood following acute administration of Ginseng to healthy young volunteers. Nutr Neurosci. 2001;4:295-310.
33. Kennedy DO, Scholey AB, Wesnes KA. Modulation of cognition and mood following administration of single doses of Ginkgo biloba, ginseng, and a ginkgo/ginseng combination to healthy young adults. Physiol Behav. 2002;75:739-751.
34. Reay JL, Kennedy DO, Scholey AB. Single doses of Panax ginseng (G115) reduce blood glucose levels and improve cognitive performance during sustained mental activity. J Psychopharmacol. 2005;19:357-365.
35. Reay JL, Kennedy DO, Scholey AB. Effects of Panax ginseng, consumed with and without glucose, on blood glucose levels and cognitive performance during sustained "mentally demanding" tasks. J Psychopharmacol. 2006;20:771-781.
36. Reay JL, Scholey AB, Kennedy DO. Panax ginseng (G115) improves aspects of working memory performance and subjective ratings of calmness in healthy young adults. Hum Psychopharmacol. 2010;25:462-471.
37. Scholey AB, Kennedy DO. Acute, dose-dependent cognitive effects of Ginkgo biloba, Panax ginseng and their combination in healthy young volunteers: differential interactions with cognitive demand. Hum Psychopharmacol. 2002;17:35-44.
38. Sorensen H, Sonne J. A double-masked study of the effects of ginseng on cognitive functions. Curr Ther Res. 1996;57:959-968.
39. Neale C, Camfield D, Reay J, etal. Cognitive effects of two nutraceuticals Ginseng and Bacopa benchmarked against modafinil: a review and comparison of effect sizes. Br J Clin Pharmacol. 2013;75:728-737.
40. Henman AR. Guarana (Paullinia cupana var. sorbilis): ecological and social perspectives on an economic plant of the central Amazon basin. J Ethnopharmacol. 1982;6:311-338.
41. Seifert SM, Schaechter JL, Hershorin ER, etal. Health effects of energy drinks on children, adolescents, and young adults. Pediatrics. 2011;127:511-528.
42. Haskell CF, Dodd FL, Wightman EL, etal. Behavioural effects of compounds co-consumed in dietary forms of caffeinated plants. Nutr Res Rev. 2013;26:49-70.
43. McLellan TM, Lieberman HR. Do energy drinks contain active components other than caffeine? Nutr Rev. 2012;70:730-744.
44. Haskell CF, Kennedy DO, Wesnes KA, etal. A double-blind, placebo-controlled, multi-dose evaluation of the acute behavioural effects of guaraná in humans. J Psychopharmacol. 2007;21:65-70.
45. Kennedy DO, Haskell CF, Wesnes KA, etal. Improved cognitive performance and mental fatigue following a multi-vitamin and mineral supplement with added guaraná (Paullinia cupana). Appetite. 2008;50:506-513.
46. Silvestrini GI, Marino F, Cosentino M. Effects of a commercial product containing guarana on psychological well-being, anxiety and mood: a single-blind, placebo-controlled study in healthy subjects. J Negat Results Biomed. 2013;12:9.
47. da Costa Miranda V, Trufelli DC, Santos J, etal. Effectiveness of guaraná (Paullinia cupana) for postradiation fatigue and depression: results of a pilot double-blind randomized study. J Altern Complement Med. 2009;15:431-433.
48. de Oliveira Campos MP, Riechelmann R, Martins LC, etal. Guaraná (Paullinia cupana) improves fatigue in breast cancer patients undergoing systemic chemotherapy. J Altern Complement Med. 2011;17:505-512.
49. Galduróz JC, Carlini EA. Acute effects of the Paulinia cupana, "Guaraná" on the cognition of normal volunteers. Sao Paulo Med J. 1994;112:607-611.
50. Galduróz JC, Carlini EA. The effects of long-term administration of guarana on the cognition of normal, elderly volunteers. Sao Paulo Med J. 1996;114:1073-1078.
51. Banderet LE, Lieberman HR. Treatment with tyrosine, a neurotransmitter precursor, reduces environmental stress in humans. Brain Res Bull. 1989;22:759-762.
52. Deijen JB, Orlebeke JF. Effect of tyrosine on cognitive function and blood pressure under stress. Brain Res Bull. 1994;33:319-323.
53. Deijen JB, Wientjes CJ, Vullinghs HF, etal. Tyrosine improves cognitive performance and reduces blood pressure in cadets after one week of a combat training course. Brain Res Bull. 1999;48:203-209.
54. Dollins AB, Krock LP, Storm WF, etal. L-tyrosine ameliorates some effects of lower body negative pressure stress. Physiol Behav. 1995;57:223-230.
55. Magill RA, Waters WF, Bray GA, etal. Effects of tyrosine, phentermine, caffeine d-amphetamine, and placebo on cognitive and motor performance deficits during sleep deprivation. Nutr Neurosci. 2003;6:237-246.
56. Mahoney CR, Castellani J, Kramer FM, etal. Tyrosine supplementation mitigates working memory decrements during cold exposure. Physiol Behav. 2007;92:575-582.
57. Neri DF, Wiegmann D, Stanny RR, etal. The effects of tyrosine on cognitive performance during extended wakefulness. Aviat Space Environ Med. 1995;66:313-319.
58. O'Brien C, Mahoney C, Tharion WJ, etal. Dietary tyrosine benefits cognitive and psychomotor performance during body cooling. Physiol Behav. 2007;90:301-307.
59. Shukitt-Hale B, Stillman MJ, Lieberman HR. Tyrosine administration prevents hypoxia-induced decrements in learning and memory. Physiol Behav. 1996;59:867-871.
60. Shurtleff D, Thomas JR, Schrot J, etal. Tyrosine reverses a cold-induced working memory deficit in humans. Pharmacol Biochem Behav. 1994;47:935-941.
61. Thomas JR, Lockwood PA, Singh A, etal. Tyrosine improves working memory in a multitasking environment. Pharmacol Biochem Behav. 1999;64:495-500.
62. Amieva H, Meillon C, Helmer C, etal. Ginkgo biloba extract and long-term cognitive decline: a 20-year follow-up population-based study. PLoS ONE. 2013;8:e52755.
63. Andrieu S, Gilette S, Amouyal K, etal. Association of Alzheimer's disease onset with Ginkgo biloba and other symptomatic cognitive treatments in a population of women aged 75 years and older from the EPIDOS study. J Gerontol A Biol Sci Med Sci. 2003;58:372-377.
64. Herrschaft H, Nacu A, Likhachev S, etal. Ginkgo biloba extract EGb 761(R) in dementia with neuropsychiatric features: a randomised, placebo-controlled trial to confirm the efficacy and safety of a daily dose of 240mg. J Psychiatr Res. 2012;46:716-723.
65. Ihl R, Tribanek M, Bachinskaya N. Baseline neuropsychiatric symptoms are effect modifiers in Ginkgo biloba extract (EGb 761[R]) treatment of dementia with neuropsychiatric features. Retrospective data analyses of a randomized controlled trial. J Neurol Sci. 2010;299:184-187.
66. Schneider LS, DeKosky ST, Farlow MR, etal. A randomized, double-blind, placebo-controlled trial of two doses of Ginkgo biloba extract in dementia of the Alzheimer's type. Curr Alzheimer Res. 2005;2:541-551.
67. DeKosky ST, Williamson JD, Fitzpatrick AL, etal. Ginkgo biloba for prevention of dementia: a randomized controlled trial. JAMA. 2008;300:2253-2262.
68. Dodge HH, Zitzelberger T, Oken BS, etal. A randomized placebo-controlled trial of Ginkgo biloba for the prevention of cognitive decline. Neurology. 2008;70(19 Pt 2):1809-1817.
69. Vellas B, Coley N, Ousset PJ, etal. Long-term use of standardised Ginkgo biloba extract for the prevention of Alzheimer's disease (GuidAge): a randomised placebo-controlled trial. Lancet Neurol. 2012;11:851-859.
70. Janssen IM, Sturtz S, Skipka G, etal. Ginkgo biloba in Alzheimer's disease: a systematic review. Wien Med Wochenschr. 2010;160:539-546.
71. Weinmann S, Roll S, Schwarzbach C, etal. Effects of Ginkgo biloba in dementia: systematic review and meta-analysis. BMC Geriatr. 2010;10:14. doi:10.1186/1471-2318-10-14.
72. Birks J, Grimley Evans J. Ginkgo biloba for cognitive impairment and dementia. Cochrane Database Syst Rev. 2007;(2):CD003120. doi:10.1002/14651858.
73. Canter PH, Ernst E. Ginkgo biloba is not a smart drug: an updated systematic review of randomised clinical trials testing the nootropic effects of G. biloba extracts in healthy people. Hum Psychopharmacol. 2007;22:265-278.
74. Roland PD, Nergard CS. Ginkgo biloba - effect, adverse events and drug interaction. Tidsskr Nor Laegeforen. 2012;132:956-959.
75. Kennedy DO, Haskell CF, Mauri PL, etal. Acute cognitive effects of standardised Ginkgo biloba extract complexed with phosphatidylserine. Hum Psychopharmacol. 2007;22:199-210.
76. Rigney U, Kimber S, Hindmarch I. The effects of acute doses of standardized Ginkgo biloba extract on memory and psychomotor performance in volunteers. Phytother Res. 1999;13:408-415.
77. Kennedy DO, Scholey AB, Wesnes KA. The dose-dependent cognitive effects of acute administration of Ginkgo biloba to healthy young volunteers. Psychopharmacology. 2000;151:416-423.
78. Kennedy DO, Jackson PA, Haskell CF, etal. Modulation of cognitive performance following single doses of 120mg Ginkgo biloba extract administered to healthy young volunteers. Hum Psychopharmacol. 2007;22:559-566.
79. Itil TM, Eralp E, Tsampis E, etal. Central nervous system effects of Ginkgo biloba, a plant extract. Am J Ther. 1996;3:63-73.
80. Kennedy DO, Scholey AB, Drewery L, etal. Electroencephalograph effects of single doses of Ginkgo biloba and Panax ginseng in healthy young volunteers. Pharmacol Biochem Behav. 2003;75:701-709.
81. Ozgoli G, Selselei EA, Mojab F, etal. A randomized, placebo-controlled trial of Ginkgo biloba L. in treatment of premenstrual syndrome. J Altern Complement Med. 2009;15:845-851.
82. Hartley DE, Heinze L, Elsabagh S, etal. Effects on cognition and mood in postmenopausal women of 1-week treatment with Ginkgo biloba. Pharmacol Biochem Behav. 2003;75:711-720.
83. Cockle SM, Kimber S, Hindmarch I. The effects of Ginkgo biloba extract (LI 1370) supplementation on activities of daily living in free living older volunteers: a questionnaire survey. Hum Psychopharmacol. 2000;15:227-235.
84. Soholm B. Clinical improvement of memory and other cognitive functions by Ginkgo biloba: review of relevant literature. Adv Ther. 1998;15:54-65.
85. Silberstein RB, Pipingas A, Song J, etal. Examining brain-cognition effects of Ginkgo biloba extract: brain activation in the left temporal and left prefrontal cortex in an object working memory task. Evid Based Complement Alternat Med. 2011;2011:164139. doi:10.1155/2011/164139.
86. Stough C, Clarke J, Lloyd J, etal. Neuropsychological changes after 30-day Ginkgo biloba administration in healthy participants. Int J Neuropsychopharmacol. 2001;4:131-134.
87. Kaschel R. Ginkgo biloba: specificity of neuropsychological improvement - a selective review in search of differential effects. Hum Psychopharmacol. 2009;24:345-370.
88. Zadoyan G, Rokitta D, Klement S, etal. Effect of Ginkgo biloba special extract EGb 761(R) on human cytochrome P450 activity: a cocktail interaction study in healthy volunteers. Eur J Clin Pharmacol. 2012;68:553-560.
89. Baggott MJ, Childs E, Hart AB, etal. Psychopharmacology of theobromine in healthy volunteers. Psychopharmacology. 2013;228:109-118.
90. Mumford GK, Evans SM, Kaminski BJ, etal. Discriminative stimulus and subjective effects of theobromine and caffeine in humans. Psychopharmacology. 1994;115:1-8.
91. Smit HJ, Gaffan EA, Rogers PJ. Methylxanthines are the psycho-pharmacologically active constituents of chocolate. Psychopharmacology. 2004;176:412-419.
92. Bartel P, Delport R, Lotz B, etal. Effects of single and repeated doses of theophylline on aspects of performance, electrophysiology and subjective assessments in healthy human subjects. Psychopharmacology. 1992;106:90-96.
93. Tiplady B, Fagan D, Lamont M, etal. A comparison of the CNS effects of enprofylline and theophylline in healthy subjects assessed by performance testing and subjective measures. Br J Clin Pharmacol. 1990;30:55-61.
94. Yu G, Maskray V, Jackson SH, etal. A comparison of the central nervous system effects of caffeine and theophylline in elderly subjects. Br J Clin Pharmacol. 1991;32:341-345.
95. Nehlig A. The neuroprotective effects of cocoa flavanol and its influence on cognitive performance. Br J Clin Pharmacol. 2013;75:716-727.
96. Macready AL, Kennedy OB, Ellis JA, etal. Flavonoids and cognitive function: a review of human randomized controlled trial studies and recommendations for future studies. Genes Nutr. 2009;4:227-242.
97. Young SN. Folate and depression - a neglected problem. J Psychiatry Neurosci. 2007;32:80-82.
98. Young SN, Ghadirian AM. Folic acid and psychopathology. Prog Neuropsychopharmacol Biol Psychiatry. 1989;13:841-863.
99. Falkingham M, Abdelhamid A, Curtis P, etal. The effects of oral iron supplementation on cognition in older children and adults: a systematic review and meta-analysis. Nutr J. 2010;9:4. doi:10.1186/1475-2891-9-4.
100. Vinod Kumar M, Rajagopalan S. Trial using multiple micronutrient food supplement and its effect on cognition. Indian J Pediatr. 2008;75:671-678.
101. Bryan J, Calvaresi E. Associations between dietary intake of folate and vitamins B-12 and B-6 and self-reported cognitive function and psychological well-being in Australian men and women in midlife. J Nutr Health Aging. 2004;8:226-232.
102. Deijen JB, van der Beek EJ, Orlebeke JF, etal. Vitamin B-6 supplementation in elderly men: effects on mood, memory, performance and mental effort. Psychopharmacology. 1992;109:489-496.
103. Bryan J, Calvaresi E, Hughes D. Short-term folate, vitamin B-12 or vitamin B-6 supplementation slightly affects memory performance but not mood in women of various ages. J Nutr. 2002;132:1345-1356.
104. Haskell CF, Robertson B, Jones F, etal. Effects of a multi-vitamin/mineral supplement on cognitive function and fatigue during extended multi-tasking. Hum Psychopharmacol. 2010;25:448-461.
105. Malouf R, Grimley Evans J. Folic acid with or without vitamin B12 for the prevention and treatment of healthy elderly and demented people. Cochrane Database Syst Rev. 2008;(4):CD004514. doi: 10.1002/14651858.CD004514.pub2.
106. Zhang M, Robitaille L, Eintracht S, etal. Vitamin C provision improves mood in acutely hospitalized patients. Nutrition. 2011;27:530-533.
107. Chui MH, Greenwood CE. Antioxidant vitamins reduce acute meal-induced memory deficits in adults with type 2 diabetes. Nutr Res. 2008;28:423-429.
108. McMorris T, Harris RC, Howard AN, etal. Creatine supplementation, sleep deprivation, cortisol, melatonin and behavior. Physiol Behav. 2007;90:21-28.
109. McMorris T, Harris RC, Swain J, etal. Effect of creatine supplementation and sleep deprivation, with mild exercise, on cognitive and psychomotor performance, mood state, and plasma concentrations of catecholamines and cortisol. Psychopharmacology. 2006;185:93-103.
110. Benton D, Donohoe R. The influence of creatine supplementation on the cognitive functioning of vegetarians and omnivores. Br J Nutr. 2011;105:1100-1105.
111. Ling J, Kritikos M, Tiplady B. Cognitive effects of creatine ethyl ester supplementation. Behav Pharmacol. 2009;20:673-679.
112. Rae C, Digney AL, McEwan SR, etal. Oral creatine monohydrate supplementation improves brain performance: a double-blind, placebo-controlled, cross-over trial. Proc Biol Sci. 2003;270:2147-2150.
113. Dixon CE, Ma X, Marion DW. Effects of CDP-choline treatment on neurobehavioral deficits after TBI and on hippocampal and neocortical acetylcholine release. J Neurotrauma. 1997;14:161-169.
114. Petkov VD, Stancheva SL, Tocuschieva L, etal. Changes in brain biogenic monoamines induced by the nootropic drugs adafenoxate and meclofenoxate and by citicholine (experiments on rats). Gen Pharmacol. 1990;21:71-75.
115. Alvarez XA, Laredo M, Corzo D, etal. Citicoline improves memory performance in elderly subjects. Methods Find Exp Clin Pharmacol. 1997;19:201-210.
116. Di Trapani G, Fioravanti M. Citicoline in the treatment of cognitive and behavioral disorders in pathologic senile decline. Clin Ter. 1991;137:403-413.
117. Spiers PA, Myers D, Hochanadel GS, etal. Citicoline improves verbal memory in aging. Arch Neurol. 1996;53:441-448.
118. Fioravanti M, Buckley AE. Citicoline (Cognizin) in the treatment of cognitive impairment. Clin Interv Aging. 2006;1:247-251.
119. Bruce SE. Improvements in quantitative EEG following consumption of a natural citicoline-enhanced beverage. Int J Food Sci Nutr. 2012;63:421-425.
120. Silveri MM, Dikan J, Ross AJ, etal. Citicoline enhances frontal lobe bioenergetics as measured by phosphorus magnetic resonance spectroscopy. NMR Biomed. 2008;21:1066-1075.
121. Cynober L. Pharmacokinetics of arginine and related amino acids. J Nutr. 2007;137(6 Suppl 2):1646S-1649S.
122. L-arginine supplementation on exercise metabolism. Curr Opin Clin Nutr Metab Care. 2007;10:46-51.
123. Bescos R, Sureda A, Tur JA, etal. The effect of nitric-oxide-related supplements on human performance. Sports Med. 2012;42:99-117.
124. L-arginine in rats. Pharmacol Biochem Behav. 2003;75:329-334.
125. L-arginine and sodium nitroprusside of ageing-induced memory impairment in rats by increasing nitric oxide concentration in the hippocampus. Indian J Physiol Pharmacol. 2005;49:179-186.
126. L-arginine on senile dementia. Am J Med. 2000;108:439. http://dx.doi.org/10.1016/S0002-9343(99)00396-4.
127. L-arginine and Alzheimer's disease. Int J Clin Exp Pathol. 2009;2:211-238.
128. Khan N, Mukhtar H. Tea and health: studies in humans. Curr Pharm Des. 2013;19:6141-6147.
129. L-theanine improves memory and attention in subjects with mild cognitive impairment: a double-blind placebo-controlled study. J Med Food. 2011;14:334-343.
130. Song J, Xu H, Liu F, etal. Tea and cognitive health in late life: current evidence and future directions. J Nutr Health Aging. 2012;16:31-34.
131. Malaguarnera M. Carnitine derivatives: clinical usefulness. Curr Opin Gastroenterol. 2012;28:166-176.
132. Malaguarnera M. Acetyl-L-carnitine in hepatic encephalopathy. Metab Brain Dis. 2013;28:193-199.
133. Montgomery SA, Thal LJ, Amrein R. Meta-analysis of double blind randomized controlled clinical trials of acetyl-L-carnitine versus placebo in the treatment of mild cognitive impairment and mild Alzheimer's disease. Int Clin Psychopharmacol. 2003;18:61-71.
134. Tempesta E, Casella L, Pirrongelli C, etal. L-acetylcarnitine in depressed elderly subjects. A cross-over study versus placebo. Drugs Exp Clin Res. 1987;13:417-423.
135. Birdsall TC. 5-Hydroxytryptophan: a clinically-effective serotonin precursor. Altern Med Rev. 1998;3:271-280.
136. Meyers S. Use of neurotransmitter precursors for treatment of depression. Altern Med Rev. 2000;5:64-71.
137. Zmilacher K, Battegay R, Gastpar M. L-5-hydroxytryptophan alone and in combination with a peripheral decarboxylase inhibitor in the treatment of depression. Neuropsychobiology. 1988;20:28-35.
138. Lynn-Bullock CP, Welshhans K, Pallas SL, etal. The effect of oral 5-HTP administration on 5-HTP and 5-HT immunoreactivity in monoaminergic brain regions of rats. J Chem Neuroanat. 2004;27:129-138.
139. Okada S, Kamb ML, Pandey JP, etal. Immunogenetic risk and protective factors for the development of L-tryptophan-associated eosinophilia-myalgia syndrome and associated symptoms. Arthritis Rheum. 2009;61:1305-1311.
140. Turner EH, Loftis JM, Blackwell AD. Serotonin a la carte: supplementation with the serotonin precursor 5-hydroxytryptophan. Pharmacol Ther. 2006;109:325-338.
141. Gendle MH, Golding AC. Oral administration of 5-hydroxytryptophan (5-HTP) impairs decision making under ambiguity but not under risk: evidence from the Iowa Gambling Task. Hum Psychopharmacol. 2010;25:491-499.
142. Gijsman HJ, van Gerven JM, de Kam ML, etal. Placebo-controlled comparison of three dose-regimens of 5-hydroxytryptophan challenge test in healthy volunteers. J Clin Psychopharmacol. 2002;22:183-189.
143. Cunliffe A, Obeid OA, Powell-Tuck J. A placebo-controlled investigation of the effects of tryptophan or placebo on subjective and objective measures of fatigue. Eur J Clin Nutr. 1998;52:425-430.
144. Gendle MH, Young EL, Romano AC. Effects of oral 5-hydroxytryptophan on a standardized planning task: insight into possible dopamine/serotonin interactions in the forebrain. Hum Psychopharmacol. 2013;28:270-273.
145. Alves MN, Ferrari-Auarek WM, Pinto KM, etal. Effects of caffeine and tryptophan on rectal temperature, metabolism, total exercise time, rate of perceived exertion and heart rate. Braz J Med Biol Res. 1995;28:705-709.
146. Kasper S, Gastpar M, Muller WE, etal. Efficacy of St. John's wort extract WS 5570 in acute treatment of mild depression: a reanalysis of data from controlled clinical trials. Eur Arch Psychiatry Clin Neurosci. 2008;258:59-63.
147. Linde K, Ramirez G, Mulrow CD, etal. St John's wort for depression - an overview and meta-analysis of randomised clinical trials. BMJ. 1996;313:253-258.
148. Brenner R, Azbel V, Madhusoodanan S, etal. Comparison of an extract of hypericum (LI 160) and sertraline in the treatment of depression: a double-blind, randomized pilot study. Clin Ther. 2000;22:411-419.
149. Schrader E. Equivalence of St John's wort extract (Ze 117) and fluoxetine: a randomized, controlled study in mild-moderate depression. Int Clin Psychopharmacol. 2000;15:61-68.
150. Wheatley D. LI 160, an extract of St. John's wort, versus amitriptyline in mildly to moderately depressed outpatients - a controlled 6-week clinical trial. Pharmacopsychiatry. 1997;30(Suppl 2):77-80.
151. Woelk H. Comparison of St John's wort and imipramine for treating depression: randomised controlled trial. BMJ. 2000;321:536-539.
152. Ernst E. Second thoughts about safety of St John's wort. Lancet. 1999;354:2014-2016.
153. Russo E, Scicchitano F, Whalley BJ, etal. Hypericum perforatum: Pharmacokinetic, Mechanism of Action, Tolerability, and Clinical Drug-Drug Interactions. Phytother Res. 2014;28:643-655.
154. Butterweck V. Mechanism of action of St John's wort in depression: what is known? CNS Drugs. 2003;17:539-562.
155. Chatterjee SS, Bhattacharya SK, Wonnemann M, etal. Hyperforin as a possible antidepressant component of Hypericum extracts. Life Sci. 1998;63:499-510.
156. Chatterjee SS, Noldner M, Koch E, etal. Antidepressant activity of Hypericum perforatum and hyperforin: the neglected possibility. Pharmacopsychiatry. 1998;31(Suppl 1):7-15.
157. Muller WE, Rolli M, Schafer C, etal. Effects of Hypericum extract (LI 160) in biochemical models of antidepressant activity. Pharmacopsychiatry. 1997;30(Suppl 2):102-107.
158. Wonnemann M, Singer A, Muller WE. Inhibition of synaptosomal uptake of 3H-L-glutamate and 3H-GABA by hyperforin, a major constituent of St. John's Wort: the role of amiloride sensitive sodium conductive pathways. Neuropsychopharmacology. 2000;23:188-197.
159. Ellis KA, Stough C, Vivetta L, etal. An investigation into the acute nootropic effects of Hypericum perforatum L. (St. John's Wort) in healthy human volunteers. Behav Pharmacol. 2001;12:173-182.
160. Timoshanko A, Stough C, Vivetta L, etal. A preliminary investigation on the acute pharmacodynamic effects of hypericum on cognitive and psychomotor performance. Behav Pharmacol. 2001;12:635-640.
161. Arold G, Donath F, Maurer A, etal. No relevant interaction with alprazolam, caffeine, tolbutamide, and digoxin by treatment with a low-hyperforin St John's wort extract. Planta Med. 2005;71:331-337.
162. Charney DS, Heninger GR. Noradrenergic function and the mechanism of action of antianxiety treatment. I. The effect of long-term alprazolam treatment. Arch Gen Psychiatry. 1985;42:458-467.
163. Halliday R, Naylor H, Brandeis D, etal. The effect of d-amphetamine, clonidine, and yohimbine on human information processing. Psychophysiology. 1994;31:331-337.
164. Mizuki Y, Suetsugi M, Ushijima I, etal. Differential effects of noradrenergic drugs on anxiety and arousal in healthy volunteers with high and low anxiety. Prog Neuropsychopharmacol Biol Psychiatry. 1996;20:1353-1367.
165. Kearney T, Tu N, Haller C. Adverse drug events associated with yohimbine-containing products: a retrospective review of the California Poison Control System reported cases. Ann Pharmacother. 2010;44:1022-1029.
166. Heck CI, de Mejia EG. Yerba Mate tea (Ilex paraguariensis): a comprehensive review on chemistry, health implications, and technological considerations. J Food Sci. 2007;72:R138-R151.
167. Bonoczk P, Panczel G, Nagy Z. Vinpocetine increases cerebral blood flow and oxygenation in stroke patients: a near infrared spectroscopy and transcranial Doppler study. Eur J Ultrasound. 2002;15:85-91.
168. Patyar S, Prakesh A, Modi M, etal. Role of vinpocetine in cerebrovascular diseases. Pharmacological Reports. 2011;63:618-628.
169. Brown JA, Buckley NA. Toxicity from bodybuilding supplements and recreational use of products containing 1, 3-dimethylamylamine. Med J Aust. 2013;198:414-415.
170. Eliason MJ, Eichner A, Cancio A, etal. Case reports: death of active duty soldiers following ingestion of dietary supplements containing 1, 3-dimethylamylamine (DMAA). Mil Med. 2012;177:1455-1459.
171. U.S. Food and Drug Administration. DMAA in Dietary Supplements. 2013. Available at: http://www.fda.gov/Food/DietarySupplements/QADietarySupplements/ucm346576.htm#FAQs. Accessed: January 2014.
172. Lieberman HR. Mental energy: assessing the cognition dimension. Nutr Rev. 2006;64(Suppl S3):S10-S13.
173. O'Connor PJ. Mental energy: assessing the mood dimension. Nutr Rev. 2006;64(Suppl S3):S7-S9.
174. O'Connor PJ. Mental energy: developing a model for examining nutrition-related claims. Nutr Rev. 2006;64(Suppl S3):S2-S6.
175. Evans SM, Griffiths RR. Caffeine withdrawal: a parametric analysis of caffeine dosing conditions. J Pharmacol Exp Ther. 1999;289:285-294.
176. Arria AM, Caldeira KM, Kasperski SJ, etal. Energy drink consumption and increased risk for alcohol dependence. Alcohol Clin Exp Res. 2011;35:365-375.
177. Arria AM, Caldeira KM, Kasperski SJ, etal. Increased alcohol consumption, nonmedical prescription drug use, and illicit drug use are associated with energy drink consumption among college students. J Addict Med. 2010;4:74-80.