1
|
Gillespie KM, White MJ, Kemps E, Moore H, Dymond A, Bartlett SE. The Impact of Free and Added Sugars on Cognitive Function: A Systematic Review and Meta-Analysis. Nutrients 2023; 16:75. [PMID: 38201905 PMCID: PMC10780393 DOI: 10.3390/nu16010075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 12/20/2023] [Accepted: 12/21/2023] [Indexed: 01/12/2024] Open
Abstract
A relationship between excessive sugar consumption and cognitive function has been described in animal models, but the specific effects of sugars in humans remains unclear. This systematic review and meta-analysis aimed to evaluate the current knowledge, research characteristics, and quality of evidence of studies investigating the impacts of free and added sugars on human cognition in healthy participants. The review identified 77 studies (65 experimental trials, n = 3831; 9 cross-sectional studies, n = 11,456; and 3 cohort studies, n = 2059). All cohort studies and eight of the nine cross-sectional studies found significant positive correlations between added sugar consumption and risk of cognitive impairment. Four studies identified reduced risk of cognitive impairment associated with natural fructose-containing foods. The majority of randomised control trials assessed short-term glucose facilitation effects on cognitive outcomes. The results from these studies suggest the need for a tightly regulated blood glucose level, dependent on individualised physiological factors, for optimal cognitive function. A meta-analysis of a subset of studies that assessed the impact of glucose on recall found improvements in immediate free recall compared to controls (p = 0.002). The findings highlight the potentially detrimental effect of excessive, long-term, or prenatal added sugar consumption on cognitive function. Further research is needed to examine the specific effects of free and added sugars on cognitive function.
Collapse
Affiliation(s)
- Kerri M. Gillespie
- School of Clinical Sciences, Faculty of Health, Queensland University of Technology, Kelvin Grove, QLD 4059, Australia;
| | - Melanie J. White
- School of Psychology and Counselling, Faculty of Health, Queensland University of Technology, Kelvin Grove, QLD 4059, Australia;
| | - Eva Kemps
- College of Education, Psychology and Social Work, Flinders University, Bedford Park, SA 5042, Australia;
| | - Halim Moore
- Laboratory of the Metabolic Adaptations to Exercise under Physiological and Pathological Conditions (AME2P), Université Clermont Auvergne, 63170 Clermont-Ferrand, France;
| | - Alexander Dymond
- Mental Health and Specialist Services, Gold Coast Hospital and Health Service, Gold Coast, QLD 4215, Australia;
| | - Selena E. Bartlett
- School of Clinical Sciences, Faculty of Health, Queensland University of Technology, Kelvin Grove, QLD 4059, Australia;
| |
Collapse
|
2
|
van der Weyden MS, Martin J, Rodriguez J, Boolani A. An Intense Bout of Acute Aerobic Exercise, but Not a Carbohydrate Supplement, Improves Cognitive Task Performance in a Sample of Black, Indigenous, and People of Color (BIPOC) Student Athletes. Sports (Basel) 2023; 11:sports11040088. [PMID: 37104162 PMCID: PMC10146807 DOI: 10.3390/sports11040088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 04/13/2023] [Accepted: 04/17/2023] [Indexed: 04/28/2023] Open
Abstract
BACKGROUND There are contradictory findings in the literature on whether an acute bout of aerobic exercise leads to a post-exercise improvement in cognitive function (CF). Moreover, participants used in the published literature are not representative of the racial make-up of sport or tactical populations. METHODS A randomized crossover design was incorporated, with participants randomly consuming water or a carbohydrate sports drink within the first 3 min of a graded maximal exercise test (GMET) conducted in a laboratory. Twelve self-identified African American participants, (seven males, five females, age = 21.42 ± 2.38 years, height = 174.94 ± 12.55 cm, mass = 82.45 ± 33.09 kg) completed both testing days. Participants completed the CF tests immediately pre- and post-GMET. CF was assessed with the Stroop color and word task (SCWT) and concentration task grid (CTG). Participants completed the GMET when they reported a score of 20 on the Borg ratings of perceived exertion scale. RESULTS Time to complete the SCWT incongruent task (p < 0.001) and CTG performance (p < 0.001) significantly improved post-GMET in both conditions. VO2max was positively correlated with pre- and post-GMET SCWT performance. CONCLUSIONS The findings of our study suggest that an acute bout of maximal exercise significantly improves CF. Additionally, cardiorespiratory fitness is positively associated with CF in our sample of student athletes from a historically Black college and university.
Collapse
Affiliation(s)
- Megan Sax van der Weyden
- Sports Medicine Assessment Research & Testing (SMART) Laboratory, George Mason University, Manassas, VA 20110, USA
| | - Joel Martin
- Sports Medicine Assessment Research & Testing (SMART) Laboratory, George Mason University, Manassas, VA 20110, USA
| | - Jose Rodriguez
- Department of Public Health, Yale University, New Haven, CT 06511, USA
| | - Ali Boolani
- Honors Program, Clarkson University, Potsdam, NY 13699, USA
| |
Collapse
|
3
|
Lorca C, Mulet M, Arévalo-Caro C, Sanchez MÁ, Perez A, Perrino M, Bach-Faig A, Aguilar-Martínez A, Vilella E, Gallart-Palau X, Serra A. Plant-derived nootropics and human cognition: A systematic review. Crit Rev Food Sci Nutr 2022; 63:5521-5545. [PMID: 34978226 DOI: 10.1080/10408398.2021.2021137] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Substances with modulatory capabilities on certain aspects of human cognition have been revered as nootropics from the dawn of time. The plant kingdom provides most of the currently available nootropics of natural origin. Here, in this systematic review, we aim to provide state-of-the-art information regarding proven and unproven effects of plant-derived nootropics (PDNs) on human cognition in conditions of health and disease. Six independent searches, one for each neurocognitive domain (NCD), were performed in parallel using three independent scientific library databases: PubMed, Cochrane and Scopus. Only scientific studies and systematic reviews with humans published between January 2000 and November 2021 were reviewed, and 256 papers were included. Ginkgo biloba was the most relevant nootropic regarding perceptual and motor functions. Bacopa monnieri improves language, learning and memory. Withania somnifera (Ashwagandha) modulates anxiety and social-related cognitions. Caffeine enhances attention and executive functions. Together, the results from the compiled studies highlight the nootropic effects and the inconsistencies regarding PDNs that require further research.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2021.2021137.
Collapse
Affiliation(s)
- Cristina Lorca
- IMDEA-Food Research Institute, +Pec Proteomics, Campus of International Excellence UAM + CSIC, Old Cantoblanco Hospital, Madrid, Spain
- Biomedical Research Institute of Lleida Dr. Pifarré Foundation (IRB Lleida) - Neuroscience Area - University Hospital Arnau de Vilanova (HUAV) - School of Medicine, University of Lleida (UdL), Lleida, Spain
- Proteored - Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - María Mulet
- Biomedical Research Institute of Lleida Dr. Pifarré Foundation (IRB Lleida) - Neuroscience Area - University Hospital Arnau de Vilanova (HUAV) - School of Medicine, University of Lleida (UdL), Lleida, Spain
| | - Catalina Arévalo-Caro
- Biomedical Research Institute of Lleida Dr. Pifarré Foundation (IRB Lleida) - Neuroscience Area - University Hospital Arnau de Vilanova (HUAV) - School of Medicine, University of Lleida (UdL), Lleida, Spain
| | - M Ángeles Sanchez
- IMDEA-Food Research Institute, +Pec Proteomics, Campus of International Excellence UAM + CSIC, Old Cantoblanco Hospital, Madrid, Spain
| | - Ainhoa Perez
- IMDEA-Food Research Institute, +Pec Proteomics, Campus of International Excellence UAM + CSIC, Old Cantoblanco Hospital, Madrid, Spain
| | - María Perrino
- IMDEA-Food Research Institute, +Pec Proteomics, Campus of International Excellence UAM + CSIC, Old Cantoblanco Hospital, Madrid, Spain
| | - Anna Bach-Faig
- FoodLab Research Group (2017SGR 83), Faculty of Health Sciences, Open University of Catalonia (UOC), Barcelona, Spain
- Food and Nutrition Area, Barcelona Official College of Pharmacists, Barcelona, Spain
| | - Alicia Aguilar-Martínez
- FoodLab Research Group (2017SGR 83), Faculty of Health Sciences, Open University of Catalonia (UOC), Barcelona, Spain
| | - Elisabet Vilella
- Hospital Universitari Institut Pere Mata (HUIPM), Institut Investigació Sanitària Pere Virgili (IISPV), Reus, Spain
- Universitat Rovira i Virgili (URV), Reus, Spain
- Centro de investigación Biomédica en Salud Mental CIBERSAM, Instituto de Salud Carlos III, Madrid, Spain
| | - Xavier Gallart-Palau
- Biomedical Research Institute of Lleida Dr. Pifarré Foundation (IRB Lleida) - Neuroscience Area - University Hospital Arnau de Vilanova (HUAV) - School of Medicine, University of Lleida (UdL), Lleida, Spain
- Proteored - Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- Hospital Universitari Institut Pere Mata (HUIPM), Institut Investigació Sanitària Pere Virgili (IISPV), Reus, Spain
- Centro de investigación Biomédica en Salud Mental CIBERSAM, Instituto de Salud Carlos III, Madrid, Spain
| | - Aida Serra
- IMDEA-Food Research Institute, +Pec Proteomics, Campus of International Excellence UAM + CSIC, Old Cantoblanco Hospital, Madrid, Spain
- Biomedical Research Institute of Lleida Dr. Pifarré Foundation (IRB Lleida) - Neuroscience Area - University Hospital Arnau de Vilanova (HUAV) - School of Medicine, University of Lleida (UdL), Lleida, Spain
- Proteored - Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| |
Collapse
|
4
|
Benau EM, Makara A, Orloff NC, Benner E, Serpell L, Timko CA. How Does Fasting Affect Cognition? An Updated Systematic Review (2013-2020). Curr Nutr Rep 2021; 10:376-390. [PMID: 34595721 DOI: 10.1007/s13668-021-00370-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2021] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW The goal of this review was to provide an update on the literature examining how voluntary, temporary abstention from eating impacts cognitive function. RECENT FINDINGS We evaluated peer-reviewed articles published between August 2013 and January 2021 that assessed adults, included a measure of cognitive functioning with neutral stimuli, and compared individuals in a fasted state to individuals in a fed state (either within- or between-subject designs). Nineteen articles (21 studies) met inclusion criteria. Sample sizes, fasting methods, and tasks varied across studies. Review of studies indicated that fasting was associated with deficits in cognitive functioning; few studies indicated a benefit in cognitive functioning following a single voluntary fast. The heterogeneity and rarity of available studies limits the conclusions that can be drawn. Several crucial psychosocial and sociodemographic moderators remain unexplored. Recommendations for future work are discussed.
Collapse
Affiliation(s)
| | - Amanda Makara
- Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | | | - Eleanor Benner
- Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | | | - C Alix Timko
- Children's Hospital of Philadelphia, Philadelphia, PA, USA.
- University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
5
|
García CR, Piernas C, Martínez-Rodríguez A, Hernández-Morante JJ. Effect of glucose and sucrose on cognition in healthy humans: a systematic review and meta-analysis of interventional studies. Nutr Rev 2021; 79:171-187. [PMID: 32585003 DOI: 10.1093/nutrit/nuaa036] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
CONTEXT Evidence suggests that plasma glucose levels may influence cognitive performance, but this has not been systematically reviewed and quantified. OBJECTIVE The aim of this review was to investigate the potential effects of glucose and sucrose, compared with placebo, on cognition in healthy humans. DATA SOURCES The electronic databases PubMed and Web of Science were searched up to December 2019. Reference lists of selected articles were checked manually. STUDY SELECTION Randomized controlled trials or crossover trials that compared glucose or sucrose with placebo for effects on cognition were eligible. DATA EXTRACTION Potentially eligible articles were selected independently by 2 authors. Risk of bias was assessed through the Cochrane Collaboration tool. Standardized mean differences (SMDs) were obtained from random-effects meta-analyses for a subsample of studies that reported the same outcomes. RESULTS Thirty-seven trials were identified, of which 35 investigated the effect of glucose consumption compared with placebo on cognition. Two studies found no effect of glucose on cognition, while the others found mixed results. Only 3 of the 37 studies investigated the effects of sucrose intake, reporting mixed results. Meta-analyses revealed a significantly positive effect of glucose compared with control, but only when a verbal performance test (immediate word recall) was used in parallel-design studies (SMD = 0.61; 95%CI, 0.20-1.02; I2 = 0%). Twenty-four studies were classified as having high risk of bias for the selection procedure. CONCLUSIONS A limited body of evidence shows a beneficial effect of glucose in individuals performing immediate verbal tasks. High-quality trials with standardized cognitive measurements are needed to better establish the effect of glucose or sucrose on cognition. SYSTEMATIC REVIEW REGISTRATION PROSPERO registration number CRD42019122939.
Collapse
Affiliation(s)
| | - Carmen Piernas
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | | | | |
Collapse
|
6
|
van de Rest O, van der Zwaluw NL, de Groot LCPGM. Effects of glucose and sucrose on mood: a systematic review of interventional studies. Nutr Rev 2019; 76:108-116. [PMID: 29228399 DOI: 10.1093/nutrit/nux065] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Context Glucose is the main energy source for the brain, and as such, manipulation of glucose supply may affect brain function. It has been suggested that a change in blood glucose may influence mood. Objective The aim of this review was to investigate the potential effects of glucose and sucrose, compared with placebo, on mood. Data Sources The electronic databases PubMed and Scopus were searched. Reference lists of selected articles were checked manually. Data Extraction Randomized controlled trials or crossover trials comparing the effects of glucose or sucrose on mood that were published up to May 2017 were eligible. Potentially eligible articles were selected independently by 2 reviewers. Results In total, 19 studies were found. Thirteen studies investigated the effects of glucose consumption compared with placebo on mood. Seven of these 13 studies found no effect of glucose on mood. The other 6 studies found small and partial effects that may also be due to other factors like palatability and expectation. Seven of the 19 studies investigated the effects of sucrose ingestion versus placebo on mood. None of these studies found a positive effect on mood, and 1 study observed an adverse effect. One of the studies investigated the effects of both glucose and sucrose. Conclusions The results from this review show limited effects of glucose ingestion on mood and no effect of sucrose on mood.
Collapse
Affiliation(s)
- Ondine van de Rest
- Division of Human Nutrition, Wageningen University & Research, Wageningen, The Netherlands
| | | | | |
Collapse
|
7
|
Nelson JM, Phillips CA, McKinley RA, McIntire LK, Goodyear C, Monforton L. The effects of transcranial direct current stimulation (tDCS) on multitasking performance and oculometrics. MILITARY PSYCHOLOGY 2019. [DOI: 10.1080/08995605.2019.1598217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
| | - Chandler A. Phillips
- Department of Industrial and Biomedical Engineering, Wright State University, Dayton, Ohio
| | - R. Andy McKinley
- Applied Neuroscience Branch, Wright-Patterson Air Force Base, Ohio
| | | | | | - Lanie Monforton
- Department of Industrial and Biomedical Engineering, Wright State University, Dayton, Ohio
| |
Collapse
|
8
|
Mantantzis K, Schlaghecken F, Sünram-Lea SI, Maylor EA. Sugar rush or sugar crash? A meta-analysis of carbohydrate effects on mood. Neurosci Biobehav Rev 2019; 101:45-67. [PMID: 30951762 DOI: 10.1016/j.neubiorev.2019.03.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 02/07/2019] [Accepted: 03/22/2019] [Indexed: 11/30/2022]
Abstract
The effect of carbohydrate (CHO) consumption on mood is much debated, with researchers reporting both mood improvements and decrements following CHO ingestion. As global consumption of sugar-sweetened products has sharply increased in recent years, examining the validity of claims of an association between CHOs and mood is of high importance. We conducted a systematic review and meta-analysis to evaluate the relationship between acute CHO ingestion and mood. We examined the time-course of CHO-mood interactions and considered the role of moderator variables potentially affecting the CHO-mood relationship. Analysis of 176 effect sizes (31 studies, 1259 participants) revealed no positive effect of CHOs on any aspect of mood at any time-point following their consumption. However, CHO administration was associated with higher levels of fatigue and less alertness compared with placebo within the first hour post-ingestion. These findings challenge the idea that CHOs can improve mood, and might be used to increase the public's awareness that the 'sugar rush' is a myth, inform health policies to decrease sugar consumption, and promote healthier alternatives.
Collapse
|
9
|
Caffeine Intake Habits and the Perception of Its Effects on Health Among College Students. Health Care Manag (Frederick) 2019; 38:44-49. [PMID: 30640237 DOI: 10.1097/hcm.0000000000000240] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The purpose of this study was to explore caffeine intake habits and the perception of its effects on health among college students. After completing a literature review on the topic of caffeine and its effects, a problem was identified relating to increased caffeine consumption and a gap in knowledge about the effects of caffeine among college students. This was a quantitative, cross-sectional study with a descriptive design. The participants were 120 college students in a campus population of about 2000 in Northern Indiana. The survey contained five demographic and 19 Likert-type statements on a 4-point scale of (1) "strongly disagree," (2) "disagree," (3) "agree," and (4) "strongly agree." Data collection occurred on the college campus at the sandwich shop, during the lunch hour. In the perception category, "Regularly consuming caffeine can have long-term negative effects on health" (mean [SD], 3.10 [0.68]) received the highest agreement. In the habit category, "I drink caffeinated beverages because I like the taste" (mean [SD], 3.11 [0.85]) received the highest agreement. In conclusion, college students are aware of the negative effects of caffeine, yet 75% consumed one or more and some exceeding five servings daily.
Collapse
|
10
|
Benson S, Tiplady B, Scholey A. Attentional and working memory performance following alcohol and energy drink: A randomised, double-blind, placebo-controlled, factorial design laboratory study. PLoS One 2019; 14:e0209239. [PMID: 30625179 PMCID: PMC6326409 DOI: 10.1371/journal.pone.0209239] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 12/03/2018] [Indexed: 11/19/2022] Open
Abstract
Alcohol mixed with energy drinks (AMED) studies have typically not shown antagonism of acute alcohol effects by energy drink (ED), particularly over relatively short time frames. This study investigated the effects of alcohol, ED, and AMED on attentional and working memory processes over a 3 h period. Twenty-four young adults took part in a randomised, double-blind, placebo-controlled, factorial, 4-arm study. They were administered 0.6g/kg alcohol and 250 ml ED (containing 80 mg caffeine), and matching placebos alone and in combination. A battery of attentional and working memory measures was completed at baseline then 45, 90 and 180 min post-treatment. Alcohol produced a characteristic shift in speed/accuracy trade-off, having little effect on reaction times while increasing errors on all attentional measures (4-choice Reaction Time, Number Pairs and Visual Search), as well as a composite Attentional error score and one working memory task (Serial Sevens). ED alone improved two working memory measures (Memory Scanning accuracy and Digit-Symbol reaction times) and improved speed of responding on a composite Working Memory score. There was no consistent pattern of AMED vs. alcohol effects; AMED produced more errors than alcohol alone on one attentional measure (Visual Search errors) at 45 min only whereas AMED resulted in fewer errors on the Serial Sevens task at 90 min and better Digit-Symbol accuracy and reaction time at 45 min. Alcohol consumption increases error rate across several attentional and working memory processes. Mutual antagonism between alcohol and ED showed no consistent pattern and likely reflects a complex interaction between caffeine and alcohol levels, phase of the blood alcohol limb, task domain and cognitive load.
Collapse
Affiliation(s)
- Sarah Benson
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, VIC, Australia
| | | | - Andrew Scholey
- Centre for Human Psychopharmacology, Swinburne University of Technology, Melbourne, VIC, Australia
| |
Collapse
|
11
|
Edmonds CJ, Harte N, Gardner M. How does drinking water affect attention and memory? The effect of mouth rinsing and mouth drying on children's performance. Physiol Behav 2018; 194:233-238. [DOI: 10.1016/j.physbeh.2018.06.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 05/16/2018] [Accepted: 06/05/2018] [Indexed: 11/30/2022]
|
12
|
Bernard BN, Louise LC, Louise D. The Effects of Carbohydrates, in Isolation and Combined with Caffeine, on Cognitive Performance and Mood-Current Evidence and Future Directions. Nutrients 2018; 10:E192. [PMID: 29425182 PMCID: PMC5852768 DOI: 10.3390/nu10020192] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 01/26/2018] [Accepted: 01/26/2018] [Indexed: 12/31/2022] Open
Abstract
This review examines the effects of carbohydrates, delivered individually and in combination with caffeine, on a range of cognitive domains and subjective mood. There is evidence for beneficial effects of glucose at a dose of 25 g on episodic memory, but exploration of dose effects has not been systematic and the effects on other cognitive domains is not known. Factors contributing to the differential sensitivity to glucose facilitation include age, task difficulty/demand, task domain, and glucoregulatory control. There is modest evidence to suggest modulating glycemic response may impact cognitive function. The evidence presented in this review identifies dose ranges of glucose and caffeine which improve cognition, but fails to find convincing consistent synergistic effects of combining caffeine and glucose. Whilst combining glucose and caffeine has been shown to facilitate cognitive performance and mood compared to placebo or glucose alone, the relative contribution of caffeine and glucose to the observed effects is difficult to ascertain, due to the paucity of studies that have appropriately compared the effects of these ingredients combined and in isolation. This review identifies a number of methodological challenges which need to be considered in the design of future hypothesis driven research in this area.
Collapse
Affiliation(s)
- Boyle Neil Bernard
- Leeds Nutrition and Behaviour Group, School of Psychology, University of Leeds, Leeds LS2 9JT, UK.
| | - Lawton Clare Louise
- Leeds Nutrition and Behaviour Group, School of Psychology, University of Leeds, Leeds LS2 9JT, UK.
| | - Dye Louise
- Leeds Nutrition and Behaviour Group, School of Psychology, University of Leeds, Leeds LS2 9JT, UK.
| |
Collapse
|
13
|
White DJ, de Klerk S, Woods W, Gondalia S, Noonan C, Scholey AB. Anti-Stress, Behavioural and Magnetoencephalography Effects of an L-Theanine-Based Nutrient Drink: A Randomised, Double-Blind, Placebo-Controlled, Crossover Trial. Nutrients 2016; 8:nu8010053. [PMID: 26797633 PMCID: PMC4728665 DOI: 10.3390/nu8010053] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 12/14/2015] [Accepted: 01/11/2016] [Indexed: 11/16/2022] Open
Abstract
l-theanine (γ-glutamylethylamide) is an amino acid found primarily in the green tea plant. This study explored the effects of an l-theanine-based nutrient drink on mood responses to a cognitive stressor. Additional measures included an assessment of cognitive performance and resting state alpha oscillatory activity using magnetoencephalography (MEG). Thirty-four healthy adults aged 18–40 participated in this double-blind, placebo-controlled, balanced crossover study. The primary outcome measure, subjective stress response to a multitasking cognitive stressor, was significantly reduced one hour after administration of the l-theanine drink when compared to placebo. The salivary cortisol response to the stressor was reduced three hours post-dose following active treatment. No treatment-related cognitive performance changes were observed. Resting state alpha oscillatory activity was significantly greater in posterior MEG sensors after active treatment compared to placebo two hours post-dose; however, this effect was only apparent for those higher in trait anxiety. This change in resting state alpha oscillatory activity was not correlated with the change in subjective stress response or the cortisol response, suggesting further research is required to assess the functional relevance of these treatment-related changes in resting alpha activity. These findings further support the anti-stress effects of l-theanine.
Collapse
Affiliation(s)
- David J White
- Centre for Human Psychopharmacology, Swinburne University of Technology, Hawthorn VIC 3122, Australia.
| | - Suzanne de Klerk
- Division of Pharmacology, Utrecht University, 3508 TC Utrecht, The Netherlands.
| | - William Woods
- Brain and Psychological Sciences Research Centre, Swinburne University of Technology, Hawthorn VIC 3122, Australia.
| | - Shakuntla Gondalia
- Centre for Human Psychopharmacology, Swinburne University of Technology, Hawthorn VIC 3122, Australia.
| | - Chris Noonan
- HealthGuidance, Inc., Santa Monica, CA 90403-5104, USA.
| | - Andrew B Scholey
- Centre for Human Psychopharmacology, Swinburne University of Technology, Hawthorn VIC 3122, Australia.
| |
Collapse
|
14
|
Feeling smart: Effects of caffeine and glucose on cognition, mood and self-judgment. Physiol Behav 2015; 151:629-37. [DOI: 10.1016/j.physbeh.2015.08.028] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 08/18/2015] [Accepted: 08/21/2015] [Indexed: 01/12/2023]
|
15
|
Abstract
Previous research has produced discrepant findings as to whether glucose administration effects lead to enhanced recollection or arise only under dual-task conditions. The aim of the present research was to address these issues by firstly employing an alternative cognitively demanding paradigm that has been linked to hippocampal function, i.e. the Process Dissociation Procedure (PDP). A second aim was to use this paradigm to explore whether glucose affects qualitative aspects of memory function. To achieve these aims, the PDP task was administered to participants who had either consumed a glucose (25 g) or aspartame-sweetened control drink. Results demonstrated glucose facilitation effects only under difficult task conditions and with no such effect emerging for the process of recollection. The present results support the contention that the beneficial effects of glucose arise under hippocampally driven, cognitively demanding task conditions, and that this effect enhances quantitative but not qualitative aspects of recognition memory.
Collapse
Affiliation(s)
- Karen R Brandt
- Department of Psychology, University of Roehampton, London, UK
| |
Collapse
|
16
|
Selected Literature Watch. JOURNAL OF CAFFEINE RESEARCH 2014. [DOI: 10.1089/jcr.2014.1243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|