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1.
Nutr Neurosci ; 25(11): 2335-2343, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34380382

RESUMO

Background: Polyphenols from coffee berry (chlorogenic acid) and apple (flavanol) have been shown to improve mood and increase cerebral blood flow in healthy humans. These effects may underpin the cognitive effects of polyphenols seen previously.Objective: The aim of the present paper was to extend previous research by investigating the effects of coffee berry at high and low doses when combined with apple extract on cognitive performance and mood.Design: This randomised, double-blind, placebo controlled, crossover trial included 46 healthy males and females,18-49 years of age (mean age 23 years),consuming: 1100 mg coffee berry extract, 1100 mg coffee berry extract plus 275 mg apple extract, 100 mg coffee berry extract plus 275 mg apple extract or placebo on 4 separate occasions, completing cognitive and mood assessments pre-dose and then again at 1-, 3- and 6 hrs post-dose.Results: Analysis revealed a consistent pattern of alerting effects following 1100 mg coffee berry extract. Limited effects on cognitive function were observed. Specifically, faster peg and ball performance (executive function) was observed following 1100 mg coffee berry plus apple extract and accuracy on the Rapid Visual Information Processing (RVIP) task increased on the third of four repetitions following 1100 mg coffee berry alone. Interestingly, more false alarms on RVIP were observed following the same intervention.Conclusions: In line with previous findings, 1100 mg coffee berry engendered increased arousal. The absence of effects on mood when an apple extract was added, and the potential for the low dose of caffeine within the coffee berry to act synergistically with polyphenols, raise interesting future avenues of research.Abbreviations: Cognitive demand battery (CDB), Profile Of Mood States (POMS), Visual Analogue Scale (VAS), Rapid Visual Information Processing (RVIP).


Assuntos
Coffea , Malus , Masculino , Feminino , Humanos , Adulto Jovem , Adulto , Estudos Cross-Over , Afeto , Cognição , Método Duplo-Cego , Extratos Vegetais/farmacologia
2.
Nutr Neurosci ; 24(11): 850-864, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31665988

RESUMO

Objective: Lack of mental energy is one of the leading reasons adults turn to dietary supplements, with three out of ten supplement users hoping to improve their energy level; even more consume caffeine-containing products for the same reason. Despite this interest from consumers, there is no consensus scientific definition of mental energy or sole validated instrument for measuring it. We performed this review to summarize main findings from research regarding the influence of natural dietary compounds on three aspects of mental energy: cognition (vigilance), motivation (to do mental work), and mood (feelings of energy and/or absence of feelings of fatigue).Methods: A narrative review of key papers.Results: In addition to caffeine, a number of other compounds, including the polyphenols, which are found in all plant-derived products, and the phytochemicals in culinary herbs and herbal products such as Panax ginseng and Ginkgo biloba, have been shown in animal models to modulate neurotransmitter activity potentially relevant to mental energy. Inadequate intake of B vitamins could also potentially have a negative effect on mental energy due to their role in overall energy production, as precursors of key cofactors in the citric acid cycle, as well as their role in brain function and neurotransmitter synthesis. Consumption of some of these products may have direct or indirect effects on one or more elements of mental energy.Conclusion: Large, prospective clinical trials of these products using appropriate, validated instruments designed to measure mental energy may be worthwhile if sufficient evidence exists to justify such trials.


Assuntos
Ginkgo biloba , Panax , Animais , Cafeína/farmacologia , Cognição , Suplementos Nutricionais , Ginkgo biloba/química , Panax/química , Estudos Prospectivos
3.
Nutr Neurosci ; 23(7): 516-525, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30289026

RESUMO

Emerging evidence from human intervention trials indicates health benefits of consuming blackcurrant fruit, including improvements to cognitive performance, modulation of blood flow, regulation of blood glucose and inhibition of enzymes underpinning normal cognitive function. Of particular relevance is our previous demonstration of monoamine oxidase (MAO)-A and B inhibition after the consumption of a New Zealand "Blackadder" blackcurrant juice in humans. The current study uses a double-blind, placebo-controlled, randomised cross- over design to assess the pharmacodynamics of the effects on platelet MAO-B inhibition and associated substrates, plasma prolactin levels and blood glucose levels after consumption of a single serve of "Blackadder" blackcurrant juice standardised to 500 mg polyphenols. Eight healthy male (20--35 years) participants completed the trial. Measurements were obtained at baseline 15, 30, 45, 60, 100, 120, 150, 180, 240 mins and 24 h post dose. A fast, absolute and reversible inhibition of blood platelet MAO-B (P < 0.001) and a significant but delayed reduction in plasma prolactin (P < 0.001) were observed following the consumption of "Blackadder" blackcurrant juice when compared to a placebo control. No interpretable changes in substrates of MAO or associated metabolites were seen. These data provide a clear time course of the reversible inhibition of MAO-B after the single consumption of a of New Zealand "Blackadder" blackcurrant juice standardised at 500 mg of polyphenols and, therefore, provide a therapeutic window on which to base future nutritional interventions.


Assuntos
Inibidores da Monoaminoxidase/administração & dosagem , Ácido gama-Linolênico/farmacocinética , Adulto , Glicemia/efeitos dos fármacos , Plaquetas , Estudos Cross-Over , Método Duplo-Cego , Humanos , Masculino , Polifenóis/farmacocinética , Prolactina/sangue , Adulto Jovem
4.
Nutr Neurosci ; 20(2): 135-151, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26618715

RESUMO

OBJECTIVES: A wild green-oats extract (Neuravena®) containing a range of potentially bioactive components, including flavonoids and triterpene saponins, has previously been shown to enhance animal stress responses and memory, and improve cognitive performance in humans at a dose of 1600 mg. Methods This double-blind, placebo-controlled, counterbalanced cross-over study assessed the effects of single doses of the green-oat extract (GOE) across a broad range of cognitive domains in healthy adults aged 40-65 years who self-reported that they felt that their memory had declined with age. Participants attended on six occasions, receiving a single dose of either placebo, 800, or 1600 mg GOE on each occasion, with the counterbalanced order of treatments repeated twice for each participant. Cognitive function was assessed with a range of computerized tasks measuring attention, spatial/working/episodic memory, and executive function pre-dose and at 1, 2.5, 4, and 6 hours post-dose. Results The results showed that 800mg GOE increased the speed of performance across post-dose assessments on a global measure including data from all of the timed tasks. It also improved performance of a delayed word recall task in terms of errors and an executive function task (Peg and Ball) in terms of decreased thinking time and overall completion time. Working memory span (Corsi blocks) was also increased, but only on the second occasion that this dose was taken. Discussion These results confirm the acute cognitive effects of GOE seen in previous research, and suggest that the optimal dose lies at or below 800 mg.


Assuntos
Envelhecimento , Avena/química , Disfunção Cognitiva/dietoterapia , Suplementos Nutricionais , Nootrópicos/uso terapêutico , Componentes Aéreos da Planta/química , Extratos Vegetais/uso terapêutico , Adulto , Idoso , Atenção , Avena/crescimento & desenvolvimento , Cápsulas , Cognição , Disfunção Cognitiva/fisiopatologia , Estudos Cross-Over , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Função Executiva , Humanos , Memória Episódica , Memória de Curto Prazo , Pessoa de Meia-Idade , Nootrópicos/administração & dosagem , Nootrópicos/efeitos adversos , Pacientes Desistentes do Tratamento , Componentes Aéreos da Planta/crescimento & desenvolvimento , Extratos Vegetais/administração & dosagem , Extratos Vegetais/efeitos adversos , Autorrelato , Memória Espacial
5.
Br J Nutr ; 114(9): 1427-37, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-26344014

RESUMO

Single doses of resveratrol have previously been shown to increase cerebral blood flow (CBF) with no clear effect on cognitive function or mood in healthy adults. Chronic resveratrol consumption may increase the poor bioavailability of resveratrol or otherwise potentiate its psychological effects. In this randomised, double-blind, placebo-controlled, parallel-groups study, a total of sixty adults aged between 18 and 30 years received either placebo or resveratrol for 28 d. On the 1st and 28th day of treatment, the performance of cognitively demanding tasks (serial subtractions, rapid visual information processing and 3-Back) (n 41 complete data sets) was assessed, alongside blood pressure (n 26) and acute (near-IR spectroscopy (NIRS)) and chronic (transcranial Doppler) measures of CBF (n 46). Subjective mood, sleep quality and health questionnaires were completed at weekly intervals (n 53/54). The results showed that the cognitive effects of resveratrol on day 1 were restricted to more accurate but slower serial subtraction task performance. The only cognitive finding on day 28 was a beneficial effect of resveratrol on the accuracy of the 3-Back task before treatment consumption. Subjective ratings of 'fatigue' were significantly lower across the entire 28 d in the resveratrol condition. Resveratrol also resulted in modulation of CBF parameters on day 1, as assessed by NIRS, and significantly increased diastolic blood pressure on day 28. Levels of resveratrol metabolites were significantly higher both before and after the day's treatment on day 28, in comparison with day 1. These results confirm the acute CBF effects of resveratrol and the lack of interpretable cognitive effects.


Assuntos
Afeto/efeitos dos fármacos , Circulação Cerebrovascular/efeitos dos fármacos , Cognição/efeitos dos fármacos , Suplementos Nutricionais , Sono/efeitos dos fármacos , Estilbenos/administração & dosagem , Adolescente , Adulto , Pressão Sanguínea/efeitos dos fármacos , Dieta , Método Duplo-Cego , Feminino , Frutas , Humanos , Masculino , Resveratrol , Inquéritos e Questionários , Análise e Desempenho de Tarefas , Verduras , Adulto Jovem
6.
Br J Nutr ; 112(2): 203-13, 2014 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-24804871

RESUMO

Previous research has shown that resveratrol can increase cerebral blood flow (CBF) in the absence of improved cognitive performance in healthy, young human subjects during the performance of cognitively demanding tasks. This lack of cognitive effects may be due to low bioavailability and, in turn, reduced bioefficacy of resveratrol in vivo. Piperine can alter polyphenol pharmacokinetics, but previous studies have not investigated whether this affects the efficacy of the target compound. Therefore, the objective of the present study was to ascertain whether co-supplementation of piperine with resveratrol affects the bioavailability and efficacy of resveratrol with regard to cognition and CBF. The present study utilised a randomised, double-blind, placebo-controlled, within-subjects design, where twenty-three adults were given placebo, trans-resveratrol (250 mg) and trans-resveratrol with 20 mg piperine on separate days at least a week apart. After a 40 min rest/absorption period, the participants performed a selection of cognitive tasks and CBF was assessed throughout the period, in the frontal cortex, using near-IR spectroscopy. The presence of resveratrol and its conjugates in the plasma was confirmed by liquid chromatography-MS analysis carried out following the administration of the same doses in a separate cohort (n 6). The results indicated that when co-supplemented, piperine and resveratrol significantly augmented CBF during task performance in comparison with placebo and resveratrol alone. Cognitive function, mood and blood pressure were not affected. The plasma concentrations of resveratrol and its metabolites were not significantly different between the treatments, which indicates that co-supplementation of piperine with resveratrol enhances the bioefficacy of resveratrol with regard to CBF effects, but not cognitive performance, and does this without altering bioavailability.


Assuntos
Alcaloides/metabolismo , Benzodioxóis/metabolismo , Circulação Cerebrovascular , Cognição , Suplementos Nutricionais , Lobo Frontal/irrigação sanguínea , Nootrópicos/metabolismo , Piperidinas/metabolismo , Alcamidas Poli-Insaturadas/metabolismo , Estilbenos/metabolismo , Adulto , Alcaloides/sangue , Alcaloides/uso terapêutico , Benzodioxóis/sangue , Benzodioxóis/uso terapêutico , Transtornos Cognitivos/sangue , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/prevenção & controle , Estudos de Coortes , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Absorção Intestinal , Masculino , Nootrópicos/agonistas , Nootrópicos/sangue , Nootrópicos/uso terapêutico , Projetos Piloto , Piperidinas/sangue , Piperidinas/uso terapêutico , Alcamidas Poli-Insaturadas/sangue , Alcamidas Poli-Insaturadas/uso terapêutico , Resveratrol , Espectroscopia de Luz Próxima ao Infravermelho , Estilbenos/agonistas , Estilbenos/sangue , Estilbenos/uso terapêutico , Análise e Desempenho de Tarefas , Adulto Jovem
7.
Front Nutr ; 11: 1298807, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38665302

RESUMO

Introduction: Extracts made from the leaves of the edible mango plant (Mangifera indica L., Anacardiaceae) have a long history of medicinal usage, most likely due to the presence of high levels of mangiferin, a polyphenol compound. Previous research has demonstrated that mango leaf extract (MLE) can beneficially modulate cognitive function in both animals and humans. This study aimed to assess the effects of an acute dose of 300 mg MLE (standardised to contain ≥60% mangiferin) on cognitive performance and mood in healthy adults. Methods: In this double-blind, placebo-controlled, crossover study, 114 healthy men and women (18-43 years) received either MLE or a matched placebo at each testing visit (separated by at least 7 days). Cognitive performance (including the cognitive demand battery) and mood were measured at 30, 180, and 300 min post-dose. Results: The results showed that, compared to placebo, the group taking MLE displayed a significant increase in serial 3 s and serial 7 s subtraction errors overall. There were no other significant effects on cognitive performance. Discussion: The results of the current study suggest that the consumption of 300 mg MLE in the absence of an observed multitasking psychological stressor does not improve cognitive performance or mood at up to 300 min post-dose. Due to the very limited nature of the effects and since they were observed among many analyses, these findings should be treated with caution.Clinical trial registration: http://ClinicalTrials.gov, identifier [NCT05182450].

8.
Br J Nutr ; 110 Suppl 1: S1-30, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23902645

RESUMO

The present review describes brain imaging technologies that can be used to assess the effects of nutritional interventions in human subjects. Specifically, we summarise the biological relevance of their outcome measures, practical use and feasibility, and recommended use in short- and long-term nutritional studies. The brain imaging technologies described consist of MRI, including diffusion tensor imaging, magnetic resonance spectroscopy and functional MRI, as well as electroencephalography/magnetoencephalography, near-IR spectroscopy, positron emission tomography and single-photon emission computerised tomography. In nutritional interventions and across the lifespan, brain imaging can detect macro- and microstructural, functional, electrophysiological and metabolic changes linked to broader functional outcomes, such as cognition. Imaging markers can be considered as specific for one or several brain processes and as surrogate instrumental endpoints that may provide sensitive measures of short- and long-term effects. For the majority of imaging measures, little information is available regarding their correlation with functional endpoints in healthy subjects; therefore, imaging markers generally cannot replace clinical endpoints that reflect the overall capacity of the brain to behaviourally respond to specific situations and stimuli. The principal added value of brain imaging measures for human nutritional intervention studies is their ability to provide unique in vivo information on the working mechanism of an intervention in hypothesis-driven research. Selection of brain imaging techniques and target markers within a given technique should mainly depend on the hypothesis regarding the mechanism of action of the intervention, level (structural, metabolic or functional) and anticipated timescale of the intervention's effects, target population, availability and costs of the techniques.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Diagnóstico por Imagem/métodos , Neuroimagem/métodos , Fenômenos Fisiológicos da Nutrição , Avaliação de Resultados em Cuidados de Saúde , Projetos de Pesquisa , Biomarcadores , Humanos
9.
Nutrients ; 15(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37299382

RESUMO

BACKGROUND: Coffeeberry extract, rich in chlorogenic acids, shows promise in improving mood and cognition, particularly when co-supplemented with phenolic compounds. However, limited work has considered the effects of coffeeberry in isolation, especially at low doses. OBJECTIVE: The current study investigated the effect of low and moderate doses of coffeeberry extract on cognition and mood. DESIGN: This randomized, double-blind, placebo-controlled crossover design investigated three active beverages on a sample of 72 healthy adults aged 18-49 years. The investigational beverages contained 100 mg or 300 mg coffeeberry extract (standardized to 40% chlorogenic acid), or 75 mg caffeine (positive control). Cognition, mood, and subjective energy were measured at baseline and then again at 60 and 120 min post-treatment. RESULTS: Analysis revealed no effect of 300 mg coffeeberry extract, while 100 mg resulted in increased mental fatigue during the performance of cognitively demanding tasks (p = 0.025) and decreased accuracy on a task of sustained attention (p = 0.003), compared to placebo, at 60 min post dose. CONCLUSIONS: Administration of 100 mg and 300 mg coffeeberry extracts revealed limited, transient negative effects following 100 mg coffeeberry. Given the large number of outcome measures analysed and the absence of findings following the 300 mg dose, these negative findings should be interpreted with caution. Overall, the findings of the current study suggest that coffeeberry extract at a low or moderate dose does not have a beneficial effect on mood, mental and physical energy levels, or cognition; higher doses, as have been administered previously, may be more effective.


Assuntos
Bebidas , Cognição , Adulto , Humanos , Estudos Cross-Over , Cafeína/farmacologia , Extratos Vegetais/farmacologia , Método Duplo-Cego , Afeto , Ácido Clorogênico
10.
Br J Nutr ; 107(8): 1232-43, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21864417

RESUMO

The n-3 PUFA are a unique class of fatty acids that cannot be manufactured by the body, and must be acquired via dietary sources. In the UK, as well as in other Western nations, these 'essential' fatty acids are consumed in quantities that fall below government guidelines. The present study explored the effects of 12 weeks' dietary supplementation with 1 g/d of two types of fish oil (FO; DHA-rich and EPA-rich) in 159 healthy young adults aged 18-35 years. An assessment of performance on a battery of computerised cognitive tasks and mood measures took place before and following the 12-week treatment regimen. Venous blood samples were also supplied by participants at both time points which were later analysed for serum fatty acid concentrations. Despite good adherence to the study protocol - as reflected in increased concentrations of n-3 serum fatty acids - compared with placebo, the observed effects of both active treatments were minimal. The only finding of note revealed that supplementation with EPA-rich FO may reduce subjective mental fatigue at times of high cognitive demand, although further investigation is required. These findings, taken together with other recent reports of null effects, suggest that dietary supplementation with n-3 PUFA in healthy, normally developing and impairment-free populations is unlikely to result in cognitive enhancement.


Assuntos
Afeto , Cognição , Suplementos Nutricionais , Óleos de Peixe/administração & dosagem , Adolescente , Adulto , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácido Eicosapentaenoico/administração & dosagem , Ácidos Graxos/sangue , Feminino , Óleos de Peixe/química , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
11.
Br J Nutr ; 107(8): 1093-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22018509

RESUMO

The impact of dietary n-3 PUFA on behavioural outcomes has been widely researched; however, very little attention has been given to their impact on brain functioning in physiological terms. A total of twenty-two healthy adults took part in this double-blind, placebo-controlled study, wherein the cerebral haemodynamic effects of 12 weeks of daily dietary supplementation with either 1 g DHA-rich or 1 g EPA-rich fish oil (FO) or placebo (1 g olive oil) were assessed. Relative changes in the concentration of oxygenated Hb (oxy-Hb) and deoxygenated Hb were assessed in the prefrontal cortex using near IR spectroscopy (NIRS) during the performance of four computerised cognitive tasks. Supplementation with DHA-rich FO, in comparison with placebo, resulted in a significant increase in the concentrations of oxy-Hb and total levels of Hb, indicative of increased cerebral blood flow (CBF), during the cognitive tasks. In comparison, no effect on CBF was observed following supplementation with EPA-rich FO, where concentration changes in the chromophores followed the same pattern as placebo. These encouraging pilot data warrant further application of NIRS in this area.


Assuntos
Circulação Cerebrovascular/efeitos dos fármacos , Cognição/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/administração & dosagem , Circulação Cerebrovascular/fisiologia , Cognição/fisiologia , Método Duplo-Cego , Ácido Eicosapentaenoico/administração & dosagem , Feminino , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Hemoglobinas/metabolismo , Humanos , Masculino , Oxiemoglobinas/metabolismo , Projetos Piloto , Espectroscopia de Luz Próxima ao Infravermelho , Análise e Desempenho de Tarefas , Adulto Jovem
12.
Hum Psychopharmacol ; 27(2): 177-86, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22389082

RESUMO

OBJECTIVE: The aim of the study was to assess the effects of oral ingestion of the 'green tea' polyphenol epigallocatechin gallate (EGCG) on cognitive performance, mood and localised cerebral blood flow (CBF) parameters in healthy human adults. METHOD: In this double-blind, placebo-controlled, crossover study, 27 healthy adults received placebo and two doses (135 and 270 mg) of EGCG in counterbalanced order on separate days. Following a 45-min resting absorption period, participants performed a selection of computerised cognitive tasks that activate the frontal cortex for a further 42 min. CBF and haemodynamics, as indexed by concentration changes in oxygenated and deoxygenated haemoglobin, were assessed in the frontal cortex throughout the post-treatment period using Near-infrared spectroscopy (NIRS). RESULTS: During the post-dose task performance period, the administration of 135 mg EGCG resulted in reduced CBF in the frontal cortex, as indexed by significantly lower concentrations of both oxygenated and total haemoglobin, in comparison with placebo. Heart rate was significantly reduced from pre dose to post dose across all treatments. No significant differences were observed for the level of deoxygenated haemoglobin or on any of the cognitive performance/mood measures. CONCLUSIONS: These results demonstrate that a single dose of orally administered EGCG can modulate CBF parameters in healthy humans but that this is not associated with changes in cognitive performance or mood.


Assuntos
Afeto/efeitos dos fármacos , Catequina/análogos & derivados , Córtex Cerebral/efeitos dos fármacos , Cognição/efeitos dos fármacos , Administração Oral , Adolescente , Adulto , Catequina/administração & dosagem , Catequina/farmacologia , Córtex Cerebral/irrigação sanguínea , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Frequência Cardíaca/efeitos dos fármacos , Hemoglobinas/metabolismo , Humanos , Masculino , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacologia , Oxiemoglobinas/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho , Adulto Jovem
13.
Sports Med ; 52(Suppl 1): 69-90, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36447122

RESUMO

The plant defence compound caffeine is widely consumed as a performance enhancer in a sporting context, with potential benefits expected in both physiological and psychological terms. However, although caffeine modestly but consistently improves alertness and fatigue, its effects on mental performance are largely restricted to improved attention or concentration. It has no consistent effect within other cognitive domains that are important to sporting performance, including working memory, executive function and long-term memory. Although caffeine's central nervous system effects are often attributed to blockade of the receptors for the inhibitory neuromodulator adenosine, it also inhibits a number of enzymes involved both in neurotransmission and in cellular homeostasis and signal propagation. Furthermore, it modulates the pharmacokinetics of other endogenous and exogenous bioactive molecules, in part via interactions with shared cytochrome P450 enzymes. Caffeine therefore enjoys interactive relationships with a wide range of bioactive medicinal and dietary compounds, potentially broadening, increasing, decreasing, or modulating the time course of their functional effects, or vice versa. This narrative review explores the mechanisms of action and efficacy of caffeine and the potential for combinations of caffeine and other dietary compounds to exert psychological effects in excess of those expected following caffeine alone. The review focusses on, and indeed restricted its untargeted search to, the most commonly consumed sources of caffeine: products derived from caffeine-synthesising plants that give us tea (Camellia sinensis), coffee (Coffea genus), cocoa (Theabroma cacao) and guaraná (Paullinia cupana), plus multi-component energy drinks and shots. This literature suggests relevant benefits to mental performance that exceed those associated with caffeine for multi-ingredient energy drinks/shots and several low-caffeine extracts, including high-flavanol cocoa and guarana. However, there is a general lack of research conducted in such a way as to disentangle the relative contributions of the component parts of these products.


Assuntos
Cacau , Paullinia , Humanos , Cafeína/farmacologia , Extratos Vegetais/farmacologia , Atenção
14.
Hum Psychopharmacol ; 26(4-5): 338-47, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21751253

RESUMO

OBJECTIVES: Despite being widely consumed, the effects of multi-vitamin supplements on psychological functioning have received little research attention. METHODS: Using a mobile phone testing paradigm, 198 males (30-55 years) in full-time employment took part in this randomised, placebo-controlled, double-blind, parallel-groups trial assessing the effects of a multi-vitamin/mineral on cognitive performance and psychological state/mood. Participants completed two cognitive tasks and a number of visual analogue scales (VAS) before and after a full day's work, on the day before, and 7, 14, 21 and 28 days after, commencing their treatment. RESULTS: Participants in the vitamin/mineral group rated themselves as having greater 'physical stamina' across assessments and weeks. They also rated themselves as having had greater 'concentration' and 'mental stamina' during the working day at the assessment carried out after a day's work, but not at the time of the assessment completed prior to work. Participants in this group also reported greater subjective 'alertness' on Bond-Lader mood scales during the post-work assessment on day 14 and both the pre and post-work assessments on day 28. CONCLUSIONS: These findings complement the results from the laboratory-based, randomised-controlled trial in the same cohort and suggest that healthy members of the general population may benefit from augmented levels of vitamins/minerals via direct dietary supplementation.


Assuntos
Ácido Ascórbico/administração & dosagem , Cálcio da Dieta/administração & dosagem , Cognição , Suplementos Nutricionais , Minerais/administração & dosagem , Substâncias para Melhoria do Desempenho/administração & dosagem , Complexo Vitamínico B/administração & dosagem , Adulto , Ácido Ascórbico/uso terapêutico , Atenção , Cálcio da Dieta/uso terapêutico , Telefone Celular , Disfunção Cognitiva/prevenção & controle , Método Duplo-Cego , Inglaterra , Fadiga/prevenção & controle , Humanos , Magnésio/administração & dosagem , Magnésio/uso terapêutico , Masculino , Pessoa de Meia-Idade , Minerais/uso terapêutico , Transtornos do Humor/prevenção & controle , Substâncias para Melhoria do Desempenho/uso terapêutico , Complexo Vitamínico B/uso terapêutico , Zinco/administração & dosagem , Zinco/uso terapêutico
15.
Nutrients ; 13(1)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466627

RESUMO

The sage (Salvia) plant contains a host of terpenes and phenolics which interact with mechanisms pertinent to brain function and improve aspects of cognitive performance. However, previous studies in humans have looked at these phytochemicals in isolation and following acute consumption only. A preclinical in vivo study in rodents, however, has demonstrated improved cognitive outcomes following 2-week consumption of CogniviaTM, a proprietary extract of both Salvia officinalis polyphenols and Salvia lavandulaefolia terpenoids, suggesting that a combination of phytochemicals from sage might be more efficacious over a longer period of time. The current study investigated the impact of this sage combination on cognitive functions in humans with acute and chronic outcomes. Participants (n = 94, 25 M, 69 F, 30-60 years old) took part in this randomised, double-blind, placebo-controlled, parallel groups design where a comprehensive array of cognitions were assessed 120- and 240-min post-dose acutely and following 29-day supplementation with either 600 mg of the sage combination or placebo. A consistent, significant benefit of the sage combination was observed throughout working memory and accuracy task outcome measures (specifically on the Corsi Blocks, Numeric Working Memory, and Name to Face Recall tasks) both acutely (i.e., changes within day 1 and day 29) and chronically (i.e., changes between day 1 to day 29). These results fall slightly outside of those reported previously with single Salvia administration, and therefore, a follow-up study with the single and combined extracts is required to confirm how these effects differ within the same cohort.


Assuntos
Cognição/efeitos dos fármacos , Extratos Vegetais/farmacologia , Salvia officinalis/química , Administração Oral , Adulto , Feminino , Humanos , Masculino , Memória/efeitos dos fármacos , Pessoa de Meia-Idade , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Polifenóis/química , Testes Psicológicos , Salvia/química
16.
Am J Clin Nutr ; 114(3): 914-924, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34113957

RESUMO

BACKGROUND: Evidence regarding the effects of the omega-3 (É·-3) PUFAs (n-3 PUFAs) DHA and EPA on cognition is lacking. OBJECTIVES: We investigated whether supplementation with oils rich in EPA or DHA improves cognition, prefrontal cortex (PFC) hemoglobin (Hb) oxygenation, and memory consolidation. METHODS: Healthy adults (n = 310; age range: 25-49 y) completed a 26-wk randomized controlled trial in which they consumed either 900 mg DHA/d and 270 mg EPA/d (DHA-rich oil), 360 mg DHA/d and 900 mg EPA/d (EPA-rich oil), or 3000 mg/d refined olive oil (placebo). Cognitive performance and memory consolidation were assessed via computerized cognitive test battery. PFC Hb oxygenation was measured using near infrared spectroscopy (NIRS). RESULTS: Both global accuracy and speed improved with EPA-rich oil compared with placebo and DHA-rich oil [EPA vs. placebo accuracy: estimated marginal mean (EMM) = 0.17 (95% CI: 0.09, 0.24) vs. EMM = 0.03 (95% CI = -0.04, 0.11); P = 0.044; EPA vs. placebo speed: EMM = -0.15 (95% CI: -0.22, -0.07) vs. EMM = 0.03 (95% CI: -0.05, 0.10); P = 0.003]. Accuracy of memory was improved with EPA compared with DHA [EMM = 0.66 (95% CI: 0.26, 1.06) vs. EMM = -0.08 (95% CI: -0.49, 0.33); P = 0.034]. Both EPA- and DHA-rich oils showed trends towards reduced PFC oxygenated Hb (oxy-Hb) compared with placebo [placebo: EMM = 27.36 µM (95% CI: 25.73, 28.98); DHA: EMM = 24.62 µM (95% CI: 22.75, 26.48); P = 0.060; EPA: EMM = 24.97 µM (95% CI: 23.35, 26.59); P = 0.082]. CONCLUSIONS: EPA supplementation improved global cognitive function and was superior to the oil enriched with DHA. Interpreted within a neural efficiency framework, reduced PFC oxygenated Hb suggests that n-3 PUFAs may be associated with increased efficiency.These trials were registered in the clinical trials registry (https://clinicaltrials.gov/) as NCT03158545, NCT03592251, NCT02763514.


Assuntos
Cognição/efeitos dos fármacos , Gorduras Insaturadas na Dieta/análise , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácidos Docosa-Hexaenoicos/farmacologia , Ácido Eicosapentaenoico/administração & dosagem , Ácido Eicosapentaenoico/farmacologia , Adulto , Ácidos Docosa-Hexaenoicos/química , Método Duplo-Cego , Ácido Eicosapentaenoico/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Nutrients ; 13(1)2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33467135

RESUMO

Emerging evidence suggests that adequate intake of omega-3 polyunsaturated fatty acids (n-3 PUFAs), which include docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), might be associated with better sleep quality. N-3 PUFAs, which must be acquired from dietary sources, are typically consumed at suboptimal levels in Western diets. Therefore, the current placebo-controlled, double-blind, randomized trial, investigated the effects of an oil rich in either DHA or EPA on sleep quality in healthy adults who habitually consumed low amounts of oily fish. Eighty-four participants aged 25-49 years completed the 26-week intervention trial. Compared to placebo, improvements in actigraphy sleep efficiency (p = 0.030) and latency (p = 0.026) were observed following the DHA-rich oil. However, these participants also reported feeling less energetic compared to the placebo (p = 0.041), and less rested (p = 0.017), and there was a trend towards feeling less ready to perform (p = 0.075) than those given EPA-rich oil. A trend towards improved sleep efficiency was identified in the EPA-rich group compared to placebo (p = 0.087), along with a significant decrease in both total time in bed (p = 0.032) and total sleep time (p = 0.019) compared to the DHA-rich oil. No significant effects of either treatment were identified for urinary excretion of the major melatonin metabolite 6-sulfatoxymelatonin. This study was the first to demonstrate some positive effects of dietary supplementation with n-3 PUFAs in healthy adult normal sleepers, and provides novel evidence showing the differential effects of n-3 PUFA supplements rich in either DHA or EPA. Further investigation into the mechanisms underpinning these observations including the effects of n-3 PUFAs on sleep architecture are required.


Assuntos
Gorduras Insaturadas na Dieta/administração & dosagem , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácidos Docosa-Hexaenoicos/farmacologia , Ingestão de Alimentos/fisiologia , Ácido Eicosapentaenoico/administração & dosagem , Ácido Eicosapentaenoico/farmacologia , Voluntários Saudáveis/psicologia , Sono/efeitos dos fármacos , Sono/fisiologia , Adulto , Dieta Ocidental , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
18.
Hum Psychopharmacol ; 25(6): 462-71, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20737519

RESUMO

OBJECTIVE: There is a lack of research into the cognitive and mood effects of repeated ginseng ingestion. The present study assessed the effects of Panax ginseng (G115) on subjective mood and aspects of 'working' memory processes, following a single dose and following sub-chronic (7 days) ingestion, in healthy volunteers. METHODS: A placebo-controlled, double-blind, randomised, crossover was utilised. Thirty volunteers (mean age 22.87 years; SD 4.01) received each treatment (200 mg; 400 mg; placebo) for 8 days, in a counter balanced order, with a 6-day wash-out period. Testing was on days 1 and 8 of each treatment period, at pre-dose, 1, 2.5 and 4 h post-dose. RESULTS: Results revealed dose-related treatment effects (p < 0.05). Two hundred milligrams slowed a fall in mood at 2.5 and 4 h on day 1 and at 1 and 4 h on day 8, but slowed responding on a mental arithmetic task across day 1 and at 1 and 2.5 h on day 8. The 400 mg dose also improved calmness (restricted 2.5 and 4 h on day 1) and improved mental arithmetic across days 1 and 8. CONCLUSIONS: We found no evidence of additional benefits, nor attenuation of acute effects following repeated ingestion of Panax ginseng (G115).


Assuntos
Afeto/efeitos dos fármacos , Memória de Curto Prazo/efeitos dos fármacos , Fadiga Mental/psicologia , Panax , Extratos Vegetais/farmacologia , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Adulto Jovem
19.
Hum Psychopharmacol ; 25(6): 448-61, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20737518

RESUMO

OBJECTIVES: A significant minority of the population consume multi-vitamins/minerals for their putative health benefits, including potentially beneficial effects on cognitive performance, fatigue and mood. The current study investigated the effect of supplementation with a multi-vitamin/mineral on fatigue and cognitive function in healthy females. METHODS: In this placebo-controlled, double blind, randomized, parallel groups trial the effect of a multi-vitamin/mineral (Supradyn) was assessed in 216 females aged 25-50 years. Participants attended the laboratory before and 9 weeks after commencing treatment. During both visits cognitive function and the modulation of task related mood/fatigue were assessed in two discrete 20-min assessment periods during which participants completed a four-module version of the Multi-Tasking Framework. RESULTS: Those in the vitamin/mineral group exhibited an attenuation of the negative effects of extended task completion on mood/fatigue. Multi-tasking performance for this group was also improved in terms of accuracy across all tasks, and on two of the individual tasks (Mathematical Processing and Stroop) in terms of both faster and more accurate responses. Analysis of a subsection (N = 102) demonstrated significant reductions in homocysteine levels following the vitamins/mineral supplement. CONCLUSIONS: These findings suggest that healthy members of the general population may benefit from augmented levels of vitamins/minerals via direct dietary supplementation.


Assuntos
Afeto/efeitos dos fármacos , Cognição/efeitos dos fármacos , Suplementos Nutricionais , Fadiga , Minerais/farmacologia , Vitaminas/farmacologia , Adulto , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Pessoa de Meia-Idade , Minerais/administração & dosagem , Minerais/uso terapêutico , Compostos Orgânicos/administração & dosagem , Compostos Orgânicos/farmacologia , Compostos Orgânicos/uso terapêutico , Vitaminas/administração & dosagem , Vitaminas/uso terapêutico
20.
Nutrients ; 12(8)2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32717999

RESUMO

Extracts made from the leaves of the mango food plant (Mangifera indica L., Anacardiaceae) have a long history of medicinal usage, most likely due to particularly high levels of the polyphenol mangiferin. In rodent models, oral mangiferin protects cognitive function and brain tissue from a number of challenges and modulates cerebro-electrical activity. Recent evidence has confirmed the latter effect in healthy humans following a mangiferin-rich mango leaf extract using quantitative electroencephalography (EEG). The current study therefore investigated the effects of a single dose of mango leaf extract, standardised to contain >60% mangiferin (Zynamite®), on cognitive function and mood. This study adopted a double-blind, placebo-controlled cross-over design in which 70 healthy young adults (18 to 45 years) received 300 mg mango leaf extract and a matched placebo, on separate occasions, separated by at least 7 days. On each occasion, cognitive/mood assessments were undertaken pre-dose and at 30 min, 3 h and 5 h post-dose using the Computerised Mental Performance Assessment System (COMPASS) assessment battery and the Profile of Mood States (POMS). The results showed that a single dose of 300 mg mango leaf extract significantly improved performance accuracy across the tasks in the battery, with domain-specific effects seen in terms of enhanced performance on an 'Accuracy of Attention' factor and an 'Episodic Memory' factor. Performance was also improved across all three tasks (Rapid Visual Information Processing, Serial 3s and Serial 7s subtraction tasks) that make up the Cognitive Demand Battery sub-section of the assessment. All of these cognitive benefits were seen across the post-dose assessments (30 min, 3 h, 5 h). There were no interpretable treatment related effects on mood. These results provide the first demonstration of cognition enhancement following consumption of mango leaf extract and add to previous research showing that polyphenols and polyphenol rich extracts can improve brain function.


Assuntos
Cognição/efeitos dos fármacos , Mangifera/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Adolescente , Adulto , Afeto/efeitos dos fármacos , Atenção/efeitos dos fármacos , Encéfalo , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Memória/efeitos dos fármacos , Memória Episódica , Pessoa de Meia-Idade , Nootrópicos/farmacologia , Folhas de Planta/química , Xantonas/farmacologia , Adulto Jovem
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