Acute effects of tea constituents L-theanine, caffeine, and epigallocatechin gallate on cognitive function and mood: A systematic review and meta-analysis

Nutrition Reviews

Volumn 72, Issue 8, 2014, Pages 507-522

  Camfield, David A ^a   Stough, Con ^a   Farrimond, Jonathon ^b   Scholey, Andrew B ^a  

^a SWINBURNE UNIVERSITY OF TECHNOLOGY   (Australia)

^b GLAXOSMITHKLINE   (United Kingdom)

Author keywords

Acute; Caffeine; Cognition; EGCG; Epigallocatechin gallate; Meta analysis; Mood; Tea; Theanine

Indexed keywords

CAFFEINE; EPIGALLOCATECHIN GALLATE; PLACEBO; THEANINE;

ALERTNESS; ANXIETY; ARTICLE; COGNITION; EFFECT SIZE; HUMAN; INFORMATION PROCESSING; MEDLINE; META ANALYSIS; MOOD; OUTCOME ASSESSMENT; OUTCOME VARIABLE; RANDOMIZED CONTROLLED TRIAL (TOPIC); REACTION TIME; STATE TRAIT ANXIETY INVENTORY; STATISTICAL ANALYSIS; SYSTEMATIC REVIEW; TEA; VISUAL ANALOG SCALE; VISUAL INFORMATION;

ACUTE; CAFFEINE; COGNITION; EGCG; EPIGALLOCATECHIN GALLATE; META-ANALYSIS; MOOD; TEA; THEANINE;

AFFECT; ATTENTION; CAFFEINE; CAMELLIA SINENSIS; CATECHIN; COGNITION; GLUTAMATES; HUMANS; PLANT EXTRACTS; TEA;

EID: 84905004766     PISSN: 00296643     EISSN: 17534887     Source Type: Journal    
DOI: 10.1111/nure.12120     Document Type: Article

References (38)

1. Arab L, Biggs ML, O'Meara ES, etal. Gender differences in tea, coffee, and cognitive decline in the elderly: the cardiovascular health study. J Alzheimers Dis. 2011;27:553-566.
2. Kuriyama S, Hozawa A, Ohmori K, etal. Green tea consumption and cognitive function: a cross-sectional study from the Tsurugaya Project. Am J Clin Nutr. 2006;83:355-361.
3. Ng TP, Feng L, Niti M, etal. Tea consumption and cognitive impairment and decline in older Chinese adults. Am J Clin Nutr. 2008;88:224-231.
4. Feng L, Gwee X, Kua EH, etal. Cognitive function and tea consumption in community dwelling older Chinese in Singapore. J Nutr Health Aging. 2010;14:433-438.
5. Hintikka J, Tolmunen T, Honkalampi K, etal. Daily tea drinking is associated with a low level of depressive symptoms in the Finnish general population. Eur J Epidemiol. 2005;20:359-363.
6. Hozawa A, Kuriyama S, Nakaya N, etal. Green tea consumption is associated with lower psychological distress in a general population: the Ohsaki Cohort 2006 Study. Am J Clin Nutr. 2009;90:1390-1396.
7. Sang S, Lambert JD, Ho CT, etal. The chemistry and biotransformation of tea constituents. Pharmacol Res. 2011;64:87-99.
8. Graham HN. Green tea composition, consumption, and polyphenol chemistry. Prev Med. 1992;21:334-350.
9. Einöther SJL, Giesbrecht T. Caffeine as an attention enhancer: reviewing existing assumptions. Psychopharmacology (Berl). 2013;225:251-274.
10. Lu K, Gray MA, Oliver C, etal. The acute effects of L-theanine in comparison with alprazolam on anticipatory anxiety in humans. Hum Psychopharmacol. 2004;19:457-465.
11. Juneja LR, Chu D, Okubo T, etal. L-Theanine, a unique amino acid of green tea and its relaxation effect in humans. Trends Food Sci Technol. 1999;10:199-204.
12. Van der Pijl PC, Chen L, Mulder TPJ. Human disposition of L-theanine in tea or aqueous solution. J Funct Foods. 2010;2:239-244.
13. Widlansky ME, Hamburg NM, Anter E, etal. Acute EGCG supplementation reverses endothelial dysfunction in patients with coronary artery disease. J Am Coll Nutr. 2007;26:95-102.
14. Scholey A, Downey LA, Ciorciari J, etal. Acute neurocognitive effects of epigallocatechin gallate (EGCG). Appetite. 2012;58:767-770.
15. Lee MJ, Maliakal P, Chen L, etal. Pharmacokinetics of tea catechins after ingestion of green tea and (-)-epigallocatechin-3-gallate by humans: formation of different metabolites and individual variability. Cancer Epidemiol Biomarkers Prev. 2002;11:1025-1032.
16. Gomez-Ramirez M, Kelly SP, Montesi JL, etal. The effects of L-theanine on alpha-band oscillatory brain activity during a visuo-spatial attention task. Brain Topogr. 2009;22:44-51.
17. Kelly SP, Gomez-Ramirez M, Montesi JL, etal. 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.
18. Dimpfel W, Kler A, Kriesl E, etal. Source density analysis of the human EEG after ingestion of a drink containing decaffeinated extract of green tea enriched with L-theanine and theogallin. Nutr Neurosci. 2007;10:169-180.
19. 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.
20. Borgwardt S, Hammann F, Scheffler K, etal. Neural effects of green tea extract on dorsolateral prefrontal cortex. Eur J Clin Nutr. 2012;66:1187-1192.
21. Wightman EL, Haskell CF, Forster JS, etal. Epigallocatechin gallate, cerebral blood flow parameters, cognitive performance and mood in healthy humans: a double-blind, placebo-controlled, crossover investigation. Hum Psychopharmacol. 2012;27:177-186.
22. Higashiyama A, Htay HH, Ozeki M, etal. Effects of l-theanine on attention and reaction time response. J Funct Foods. 2011;3:171-178.
23. De Bruin EA, Rowson MJ, Van Buren L, etal. Black tea improves attention and self-reported alertness. Appetite. 2011;56:235-240.
24. Einöther SJL, Martens VEG, Rycroft JA, etal. l-Theanine and caffeine improve task switching but not intersensory attention or subjective alertness. Appetite. 2010;54:406-409.
25. Giesbrecht T, Rycroft JA, Rowson MJ, etal. The combination of L-theanine and caffeine improves cognitive performance and increases subjective alertness. Nutr Neurosci. 2010;13:283-290.
26. Owen GN, Parnell H, De Bruin EA, etal. The combined effects of L-theanine and caffeine on cognitive performance and mood. Nutr Neurosci. 2008;11:193-199.
27. 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.
28. 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 (Berl). 2008;195:569-577.
29. Kimura K, Ozeki M, Juneja LR, etal. L-Theanine reduces psychological and physiological stress responses. Biol Psychol. 2007;74:39-45.
30. Bond A, Lader M. The use of analogue scales in rating subjective feelings. Brit J Psychol. 1974;47:211-218.
31. Rogers PJ, Richardson NJ, Elliman NA. Overnight caffeine abstinence and negative reinforcement of preference for caffeine-containing drinks. Psychopharmacology (Berl). 1995;120:457-462.
32. Spielberger CD, Gorsuch RL, Lushene RE. STAI: Manual for the State-Trait Anxiety Inventory. Palo Alto, CA: Consulting Psychologists Press; 1969.
33. Monsell S. Task switching. Trends Cogn Sci. 2003;7:134-140.
34. Elbourne DR, Altman DG, Higgins JPT, etal. Meta-analyses involving cross-over trials: methodological issues. Int J Epidemiol. 2002;31:140-149.
35. Viechtbauer W. Conducting meta-analyses in R with the metafor package. J Stat Softw. 2010;36:1-48.
36. Hedges LV, Olkin I. Statistical Methods for Meta-Analysis. San Diego, CA: Academic Press; 1985.
37. Begg CB, Mazumdar M. Operating characteristics of a rank correlation test for publication bias. Biometrics. 1994;50:1088-1101.
38. Egger M, Smith GD, Schneider M, etal. Bias in meta-analysis detected by a simple, graphical test. Br Med J. 1997;315:629-634.