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Lin Z, Wei J, Hu Y, Pi D, Jiang M, Lang T. Caffeine Synthesis and Its Mechanism and Application by Microbial Degradation, A Review. Foods 2023; 12:2721. [PMID: 37509813 PMCID: PMC10380055 DOI: 10.3390/foods12142721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 07/10/2023] [Accepted: 07/10/2023] [Indexed: 07/30/2023] Open
Abstract
Caffeine is a metabolite derived from purine nucleotides, typically accounting for 2-5% of the dry weight of tea and 1-2% of the dry weight of coffee. In the tea and coffee plants, the main synthesis pathway of caffeine is a four-step sequence consisting of three methylation reactions and one nucleosidase reaction using xanthine as a precursor. In bacteria, caffeine degradation occurs mainly through the pathways of N-demethylation and C-8 oxidation. However, a study fully and systematically summarizing the metabolism and application of caffeine in microorganisms has not been established elsewhere. In the present study, we provide a review of the biosynthesis, microbial degradation, gene expression, and application of caffeine microbial degradation. The present review aims to further elaborate the mechanism of caffeine metabolism by microorganisms and explore the development prospects in this field.
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Affiliation(s)
- Zhipeng Lin
- School of Chemistry and Chemical Engineering, Guangxi Minzu University, Nanning 530008, China
- Guangxi Key Laboratory for Polysaccharide Materials and Modifications, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530008, China
| | - Jian Wei
- Institute of Ecology, College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of Ministry of Education, Peking University, Beijing 100091, China
| | - Yongqiang Hu
- Guangxi Key Laboratory for Polysaccharide Materials and Modifications, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530008, China
| | - Dujuan Pi
- Guangxi Key Laboratory for Polysaccharide Materials and Modifications, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530008, China
| | - Mingguo Jiang
- School of Chemistry and Chemical Engineering, Guangxi Minzu University, Nanning 530008, China
- Guangxi Key Laboratory for Polysaccharide Materials and Modifications, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530008, China
| | - Tao Lang
- MNR Key Laboratory for Geo-Environmental Monitoring of Great Bay Area & Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518071, China
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Ledesma ALL, Leite Rodrigues D, Monteiro de Castro Silva I, Oliveira CA, Bahmad F. The effect of caffeine on tinnitus: Randomized triple-blind placebo-controlled clinical trial. PLoS One 2021; 16:e0256275. [PMID: 34543285 PMCID: PMC8452027 DOI: 10.1371/journal.pone.0256275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 07/19/2021] [Indexed: 11/18/2022] Open
Abstract
Objective To test the hypothesis that caffeine can influence tinnitus, we recruited 80 patients with chronic tinnitus and randomly allocated them into two groups (caffeine and placebo) to analyze the self-perception of tinnitus symptoms after caffeine consumption, assuming that this is an adequate sample for generalization. Methods The participants were randomized into two groups: one group was administered a 300-mg capsule of caffeine, and the other group was given a placebo capsule (cornstarch). A diet that restricted caffeine consumption for 24 hours was implemented. The participants answered questionnaires (the Tinnitus Handicap Inventory—THI, the Visual Analog Scale—VAS, the profile of mood state—POMS) and underwent examinations (tonal and high frequency audiometry, acufenometry (frequency measure; intensity measure and the minimum level of tinnitus masking), transient otoacoustic emissions—TEOAE and distortion product otoacoustic emissions—DPOAE assessments) at two timepoints: at baseline and after capsule ingestion. Results There was a significant change in mood (measured by the POMS) after caffeine consumption. The THI and VAS scores were improved at the second timepoint in both groups. The audiometry assessment showed a significant difference in some frequencies between baseline and follow-up measurements in both groups, but these differences were not clinically relevant. Similar findings were observed for the amplitude and signal-to-noise ratio in the TEOAE and DPOAE measurements. Conclusions Caffeine (300 mg) did not significantly alter the psychoacoustic measures, electroacoustic measures or the tinnitus-related degree of discomfort.
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Affiliation(s)
- Alleluia Lima Losno Ledesma
- Postgraduate Program in Health Sciences at the Faculty of Health Sciences, University of Brasília, Brasília, DF, Brazil
| | | | | | - Carlos Augusto Oliveira
- Postgraduate Program in Health Sciences at the Faculty of Health Sciences, University of Brasília, Brasília, DF, Brazil
| | - Fayez Bahmad
- Postgraduate Program in Health Sciences at the Faculty of Health Sciences, University of Brasília, Brasília, DF, Brazil
- Institute of Otorhinolaryngology, Brasília, DF, Brazil
- * E-mail:
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Morris C, Elgar J. Impact of caffeine and information relating to caffeine on young adults' liking, healthiness perception and intended use of model energy drinks. Lebensm Wiss Technol 2020. [DOI: 10.1016/j.lwt.2020.109879] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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4
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McCormick DP, Reyna L, Reifsnider E. Calories, Caffeine and the Onset of Obesity in Young Children. Acad Pediatr 2020; 20:801-808. [PMID: 32081767 PMCID: PMC7416448 DOI: 10.1016/j.acap.2020.02.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 02/11/2020] [Accepted: 02/13/2020] [Indexed: 12/24/2022]
Abstract
OBJECTIVE High calorie foods and beverages, which often contain caffeine, contribute to child overweight/obesity. We evaluated the results of an educational intervention to promote healthy growth in very young children. Secondarily, we used detailed diet data to explore the association of nutrient intake with the early development of overweight and obesity. METHODS Mothers were obese Latina women, enrolled prenatally, and their infants. Specially trained community health workers provided breastfeeding support and nutrition education during 10 home visits, birth to 24 months. At follow-up, age 18 to 36 months, we measured growth and completed detailed diet recalls (1-7 recall days/child). RESULTS Of 174 infants randomized, 106 children were followed for 24 to 36 months. The educational intervention did not prevent overweight/obesity. Forty-two percent of children became overweight or obese. Fifty-eight percent of children consumed caffeine on at least 1 recall day. Mean intake was 0.48 mg/kg/day. Caffeine correlated with higher consumption of calories, and added sugar and decreased intake of protein, fiber and dairy. Compared with days without caffeine, on days when caffeine was consumed, children ingested 121 more calories and 3.8 gm less protein. Children frequently consumed less than the recommended daily intake of key nutrients such as fiber, vegetables, whole fruit, and vitamins. CONCLUSIONS Caffeine was a marker for increased intake of calories and decreased intake of key nutrients. When discussing dietary intake in early childhood, practitioners should screen for nutrient deficiency in young children and recommend limiting the intake of caffeinated foods and beverages.
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Juliano LM, Kardel PG, Harrell PT, Muench C, Edwards KC. Investigating the role of expectancy in caffeine withdrawal using the balanced placebo design. Hum Psychopharmacol 2019; 34:e2692. [PMID: 30861208 DOI: 10.1002/hup.2692] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 11/20/2018] [Accepted: 01/18/2019] [Indexed: 01/11/2023]
Abstract
OBJECTIVE This study investigated psychological influences on drug withdrawal symptomatology using a caffeine-based model. METHODS Using the 2 × 2 balanced placebo design caffeine dose (given caffeinated vs decaffeinated coffee) was crossed with dose expectancy (told caffeine vs. decaf) among 87 (16-hr abstinent) regular coffee consumers in a 2-day study. RESULTS There were effects of expectancy and pharmacology that differed depending on the measure. Those told decaf reported greater caffeine cravings than those told caffeine 45 min and 8 hr postmanipulation. There were no expectancy effects on withdrawal symptoms or cognitive performance. There were pharmacological effects on all measures. Those given decaf reported greater withdrawal symptoms and showed poorer cognitive performance 45 min and 8 hr postmanipulation, with effects for headache and flu-like symptoms first emerging 8 hr postmanipulation (i.e., 24 hr abstinence in given decaf conditions). Caffeine readministration alleviated all withdrawal symptoms and cognitive decrements within 45 min. No drug by expectancy interactions were observed. CONCLUSIONS These findings confirm a strong pharmacological basis for caffeine withdrawal and an important role of cognition in drug craving. Future research should investigate the role of expectancy in drug withdrawal and craving and the potential use of expectancy manipulations in symptom prevention and management.
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Affiliation(s)
- Laura M Juliano
- Department of Psychology, American University, Washington, DC, USA
| | - Peter G Kardel
- Department of Psychology, American University, Washington, DC, USA.,Moran Company, Arlington, Virginia, USA
| | - Paul T Harrell
- Department of Psychology, American University, Washington, DC, USA.,Division of Community Health & Research, Department of Pediatrics, Eastern Virginia Medical School, Norfolk, Virginia, USA
| | - Christine Muench
- Department of Psychology, American University, Washington, DC, USA.,Section on Clinical Genomics and Experimental Therapeutics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland, USA
| | - Kathryn C Edwards
- Department of Psychology, American University, Washington, DC, USA.,Behavioral Health Group, Westat, Rockville, Maryland, USA
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Taste Perception and Caffeine Consumption: An fMRI Study. Nutrients 2018; 11:nu11010034. [PMID: 30586867 PMCID: PMC6356791 DOI: 10.3390/nu11010034] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 11/21/2018] [Accepted: 12/18/2018] [Indexed: 12/14/2022] Open
Abstract
Caffeine is ubiquitous, yet its impact on central taste processing is not well understood. Although there has been considerable research on caffeine’s physiological and cognitive effects, there is a paucity of research investigating the effects of caffeine on taste. Here we used functional magnetic resonance imaging (fMRI) to investigate group differences between caffeine consumers and non-consumers in blood-oxygenation-level-dependent (BOLD) activation during hedonic evaluation of taste. We scanned 14 caffeine consumers and 14 caffeine non-consumers at 3 Tesla, while they rated three tastes: caffeine (bitter), sucrose (sweet), and saccharin (sweet with bitter after taste), in aqueous solutions. Differences in BOLD activation were analyzed using voxel wise independent samples t-tests within Analysis of Functional Neuroimage (AFNI). Results indicated that during the hedonic evaluation of caffeine or sucrose, caffeine non-consumers had significantly greater activation in neuronal areas associated with memory and reward. During the hedonic evaluation of saccharin, caffeine consumers had significantly greater activation in areas associated with memory and information processing. The findings suggest caffeine consumption is associated with differential activation in neuronal areas involved in reward, memory, and information processing. Further research on intensity and hedonics of bitter and sweet stimuli in caffeine consumers and non-consumers will be of great interest to better understand the nature of differences in taste perception between caffeine consumers and non-consumers.
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Dos Santos MKF, Gavioli EC, Rosa LS, de Paula Soares-Rachetti V, Lobão-Soares B. Craving espresso: the dialetics in classifying caffeine as an abuse drug. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2018; 391:1301-1318. [PMID: 30338342 DOI: 10.1007/s00210-018-1570-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 09/28/2018] [Indexed: 11/29/2022]
Abstract
Caffeine is the most consumed psychoactive substance in the world; in general, it is not associated to potentially harmful effects. Nevertheless, few studies were performed attempting to investigate the caffeine addiction. The present review was mainly aimed to answer the following question: is caffeine an abuse drug? To adress this point, the effects of caffeine in preclinical and clinical studies were summarized and critically analyzed taking account the abuse disorders described in the Diagnostic and Statistical Manual of Mental Disorders (DSM-V). We concluded that the diagnostic criteria evidenced on DSM-V to intoxication-continued use and abstinence are not well supported by clinical studies. The fact that diagnostic criteria is not widely supported by preclinical or clinical studies may be due specially to a controversy in its exactly mechanism of action: recent literature point to an indirect, rather than direct modulation of dopamine receptors, and auto-limitant consumption due to adverse sensations in high doses. On the other hand, it reports clear withdrawal-related symptoms. Thus, based on a classical action on reward system, caffeine only partially fits its mechanism of action as an abuse drug, especially because previous research does not report a clear effect of dopaminergic activity enhance on nucleus accumbens; despite this, there are reports concerning dopaminergic modulation by caffeine on the striatum. However, based on human and animal research, caffeine withdrawal evokes signals and symptoms, which are relevant enough to include this substance among the drugs of abuse.
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Affiliation(s)
- Max Kenedy Felix Dos Santos
- Departamento de Biofísica e Farmacologia, Universidade Federal do Rio Grande do Norte, Av. Senador Salgado Filho 3000 Lagoa Nova, Natal, RN, 59078-970, Brazil
| | - Elaine C Gavioli
- Departamento de Biofísica e Farmacologia, Universidade Federal do Rio Grande do Norte, Av. Senador Salgado Filho 3000 Lagoa Nova, Natal, RN, 59078-970, Brazil
| | - Lorena Santa Rosa
- Departamento de Biofísica e Farmacologia, Universidade Federal do Rio Grande do Norte, Av. Senador Salgado Filho 3000 Lagoa Nova, Natal, RN, 59078-970, Brazil
| | - Vanessa de Paula Soares-Rachetti
- Departamento de Biofísica e Farmacologia, Universidade Federal do Rio Grande do Norte, Av. Senador Salgado Filho 3000 Lagoa Nova, Natal, RN, 59078-970, Brazil
| | - Bruno Lobão-Soares
- Departamento de Biofísica e Farmacologia, Universidade Federal do Rio Grande do Norte, Av. Senador Salgado Filho 3000 Lagoa Nova, Natal, RN, 59078-970, Brazil.
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Abstract
Psychiatrists rarely enquire about caffeine intake when assessing patients. This may lead to a failure to identify caffeine-related problems and offer appropriate interventions. Excessive caffeine ingestion leads to symptoms that overlap with those of many psychiatric disorders. Caffeine is implicated in the exacerbation of anxiety and sleep disorders, and people with eating disorders often misuse it. It antagonises adenosine receptors, which may potentiate dopaminergic activity and exacerbate psychosis. In psychiatric in-patients, caffeine has been found to increase anxiety, hostility and psychotic symptoms. Assessment of caffeine intake should form part of routine psychiatric assessment and should be carried out before prescribing hypnotics. Gradual reduction in intake or gradual substitution with caffeine-free alternatives is probably preferable to abrupt cessation. Decaffeinated beverages should be provided on psychiatric wards.
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Koffarnus MN, Kaplan BA. Clinical models of decision making in addiction. Pharmacol Biochem Behav 2018; 164:71-83. [PMID: 28851586 PMCID: PMC5747979 DOI: 10.1016/j.pbb.2017.08.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 08/08/2017] [Accepted: 08/21/2017] [Indexed: 01/25/2023]
Abstract
As research on decision making in addiction accumulates, it is increasingly clear that decision-making processes are dysfunctional in addiction and that this dysfunction may be fundamental to the initiation and maintenance of addictive behavior. How drug-dependent individuals value and choose among drug and nondrug rewards is consistently different from non-dependent individuals. The present review focuses on the assessment of decision-making in addiction. We cover the common behavioral tasks that have shown to be fruitful in decision-making research and highlight analytical and graphical considerations, when available, to facilitate comparisons within and among studies. Delay discounting tasks, drug demand tasks, drug choice tasks, the Iowa Gambling Task, and the Balloon Analogue Risk Task are included.
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Affiliation(s)
- Mikhail N Koffarnus
- Virginia Tech Carilion Research Institute, 2 Riverside Circle, Roanoke, VA 24016, United States.
| | - Brent A Kaplan
- Virginia Tech Carilion Research Institute, 2 Riverside Circle, Roanoke, VA 24016, United States
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The Effects of Caffeine, Taurine, or Caffeine-Taurine Coingestion on Repeat-Sprint Cycling Performance and Physiological Responses. Int J Sports Physiol Perform 2017; 12:1341-1347. [DOI: 10.1123/ijspp.2016-0570] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Purpose: To investigate the effects of caffeine (C), taurine (T), caffeine and taurine coingestion (C +T), or placebo (P) on repeated Wingate cycling performance and associated physiological responses. Methods: Seven male team-sport players participated in a randomized, single-blind, crossover study, where they completed 3 Wingate tests, each separated by 2 min, an hour after ingesting: C (5 mg/kg body mass [BM]), T (50 mg/kg BM), C +T (5 mg/kg BM + 50 mg/kg BM), or P (5 mg/kg BM) in a gelatin capsule. Performance was measured on an ergometer, and blood lactate, perceived exertion, heart rate (HR), mean arterial pressure (MAP), and rate pressure product (RPP) were measured at rest (presupplement), baseline (1 h postsupplement), and during and after exercise. Results: Magnitude-based inferences revealed that all of the supplements increased (small to moderate, likely to very likely) mean peak power (MPP), peak power (PP), and mean power (MP) compared to P, with greater MPP, PP, and MP in T compared to C (small, possible). Intrasprint fatigue index (%FIIntra) was greater in T compared to P and C (moderate, likely), and %FIInter was lower in T compared to C (small, possible). C and C +T increased HR, MAP, and RPP compared to P and T at baseline (moderate to very large, likely to most likely); however, these only remained higher in C compared to all conditions in the final sprint. Conclusions: T elicited greater improvements in performance compared to P, C, or C +T while reducing the typical chronotropic and pressor effects of C.
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Arulkadacham LJ, Richardson B, Staiger PK, Kambouropoulos N, O'Donnell RL, Ling M. Dissociation between wanting and liking for alcohol and caffeine: A test of the Incentive Sensitisation Theory. J Psychopharmacol 2017. [PMID: 28627332 DOI: 10.1177/0269881117711711] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Limited human studies have directly tested the dissociation between wanting and liking with human substance users, a core tenet of the Incentive Sensitisation Theory (IST). The aim of this study is to test the dissociation between wanting and liking in humans across two commonly used licit substances, alcohol and caffeine. The STRAP-R (Sensitivity To Reinforcement of Addictive and other Primary Rewards) questionnaire was administered to 285 alcohol users (mean age=33.30, SD= 8.83) and 134 coffee users (mean age=33.05, SD=8.10) ranging in their levels of substance use to assess wanting and liking. Findings showed that in high risk alcohol users wanting may drive alcohol consumption more so than liking, compared with low risk alcohol users. However, wanting and liking did not significantly dissociate as alcohol consumption increased. These findings partially support IST. Additionally, IST was not supported in coffee users. It is possible that caffeine functions differently at the neurological level compared with alcohol, perhaps explaining the lack of dissociation emerging in coffee users as caffeine use increased. Nevertheless, the current study makes several contributions to IST research. Future studies should focus on utilising the STRAP-R with a clinically dependent sample to test the dissociation between wanting and liking.
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Affiliation(s)
- Lilani J Arulkadacham
- 1 Faculty of Health, School of Psychology, Deakin University, Melbourne, VIC, Australia
| | - Ben Richardson
- 1 Faculty of Health, School of Psychology, Deakin University, Melbourne, VIC, Australia.,2 Cairnmillar Institute, School of Psychology, Counselling and Psychotherapy, Melbourne, VIC, Australia
| | - Petra K Staiger
- 1 Faculty of Health, School of Psychology, Deakin University, Melbourne, VIC, Australia
| | | | - Renée L O'Donnell
- 1 Faculty of Health, School of Psychology, Deakin University, Melbourne, VIC, Australia
| | - Mathew Ling
- 1 Faculty of Health, School of Psychology, Deakin University, Melbourne, VIC, Australia
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Caffeine increases sugar-sweetened beverage consumption in a free-living population: a randomised controlled trial. Br J Nutr 2015; 113:366-71. [PMID: 25567475 PMCID: PMC4302390 DOI: 10.1017/s000711451400378x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Excessive sugar-sweetened beverage (SSB) consumption has been associated with overweight and obesity. Caffeine is a common additive to SSB, and through dependence effects, it has the potential to promote the consumption of caffeine-containing foods. The objective of the present study was to assess the influence that caffeine has on the consumption of SSB. Participants (n 99) were blindly assigned to either a caffeinated SSB (C-SSB) or a non-caffeinated SSB (NC-SSB) group. Following randomisation, all participants completed a 9 d flavour-conditioning paradigm. They then completed a 28 d ad libitum intake intervention where they consumed as much or as little of C-SSB or NC-SSB as desired. The amount consumed (ml) was recorded daily, 4 d diet diaries were collected and liking of SSB was assessed at the start and end of the intervention. Participants (n 50) consuming the C-SSB had a daily SSB intake of 419 (sd 298) ml (785 (sd 559) kJ/d) over the 28 d intervention, significantly more than participants (n 49) consuming the NC-SSB (273 (sd 278) ml/d, 512 (sd 521) kJ/d) (P< 0·001). A trained flavour panel (n 30) found no difference in flavour between the C-SSB and NC-SSB (P>0·05). However, participants who consumed the C-SSB liked the SSB more than those who consumed the NC-SSB (6·3 v. 6·0 on a nine-point hedonic scale, P= 0·022). The addition of low concentrations of caffeine to the SSB significantly increases the consumption of the SSB. Regulating caffeine as a food additive may be an effective strategy to decrease the consumption of nutrient-poor high-energy foods and beverages.
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Häusser JA, Schlemmer A, Kaiser S, Kalis A, Mojzisch A. The effects of caffeine on option generation and subsequent choice. Psychopharmacology (Berl) 2014; 231:3719-27. [PMID: 24682504 DOI: 10.1007/s00213-014-3506-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Accepted: 02/12/2014] [Indexed: 11/30/2022]
Abstract
RATIONALE Although the effects of caffeine on basic cognitive functions are well-known, its effects on more complex decision making, particularly on option generation, is yet to be explored. OBJECTIVE We examined the effects of caffeine on option generation in decision making using everyday life decisional situations. METHODS In a double-blind placebo-controlled experiment, participants (N = 47) either received 300 mg of caffeine or a placebo. Participants had to generate choice options (things they could do) for a series of high and low familiar real-world scenarios and, subsequently, to decide among these options. RESULTS Analyses revealed that participants in the caffeine condition generated significantly fewer options than participants in the placebo condition. Moreover, caffeine significantly reduced the option generation onset time, that is, participants in the caffeine condition generated their first option significantly faster than participants in the placebo condition. Regarding subsequent choice, we found evidence supporting the "take-the-first" heuristic, that is, the tendency to select the first generated option. This tendency was neither affected by caffeine nor by the familiarity of the scenarios. CONCLUSIONS Caffeine results in fewer options generated in unconstrained real-life decision-making situations and decreases generation onset times.
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Affiliation(s)
- Jan Alexander Häusser
- Institute of Psychology, University of Hildesheim, Marienburger Platz 22, 37141, Hildesheim, Germany,
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Chan KK, Ganguly R, Li Y, Webster RD. Electrochemically Controlled One-Electron Oxidation Coupled to Consecutive Hydrogen Atom Transfer of Caffeine. ChemElectroChem 2014. [DOI: 10.1002/celc.201402203] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Meredith SE, Juliano LM, Hughes JR, Griffiths RR. Caffeine Use Disorder: A Comprehensive Review and Research Agenda. JOURNAL OF CAFFEINE RESEARCH 2013; 3:114-130. [PMID: 24761279 DOI: 10.1089/jcr.2013.0016] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Caffeine is the most commonly used drug in the world. Although consumption of low to moderate doses of caffeine is generally safe, an increasing number of clinical studies are showing that some caffeine users become dependent on the drug and are unable to reduce consumption despite knowledge of recurrent health problems associated with continued use. Thus, the World Health Organization and some health care professionals recognize caffeine dependence as a clinical disorder. In this comprehensive literature review, we summarize published research on the biological evidence for caffeine dependence; we provide a systematic review of the prevalence of caffeine dependence and rates of endorsement of clinically meaningful indicators of distress and functional impairment among habitual caffeine users; we discuss the diagnostic criteria for Caffeine Use Disorder-a condition for further study included in the Diagnostic and Statistical Manual of Mental Disorders (5th ed.); and we outline a research agenda to help guide future clinical, epidemiological, and genetic investigations of caffeine dependence. Numerous controlled laboratory investigations reviewed in this article show that caffeine produces behavioral and physiological effects similar to other drugs of dependence. Moreover, several recent clinical studies indicate that caffeine dependence is a clinically meaningful disorder that affects a nontrivial proportion of caffeine users. Nevertheless, more research is needed to determine the reliability, validity, and prevalence of this clinically important health problem.
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Affiliation(s)
- Steven E Meredith
- Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine , Baltimore, Maryland
| | - Laura M Juliano
- Department of Psychology, American University , Washington, District of Columbia
| | - John R Hughes
- Department of Psychology, University of Vermont , Burlington, Vermont. ; Department of Psychiatry, University of Vermont , Burlington, Vermont
| | - Roland R Griffiths
- Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine , Baltimore, Maryland. ; Department of Neuroscience, The Johns Hopkins University School of Medicine , Baltimore, Maryland
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Dresler M, Sandberg A, Ohla K, Bublitz C, Trenado C, Mroczko-Wąsowicz A, Kühn S, Repantis D. Non-pharmacological cognitive enhancement. Neuropharmacology 2013; 64:529-43. [DOI: 10.1016/j.neuropharm.2012.07.002] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Revised: 06/30/2012] [Accepted: 07/02/2012] [Indexed: 10/28/2022]
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17
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Sheppard AB, Gross SC, Pavelka SA, Hall MJ, Palmatier MI. Caffeine increases the motivation to obtain non-drug reinforcers in rats. Drug Alcohol Depend 2012; 124:216-22. [PMID: 22336397 PMCID: PMC3383337 DOI: 10.1016/j.drugalcdep.2012.01.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 01/17/2012] [Accepted: 01/17/2012] [Indexed: 12/16/2022]
Abstract
BACKGROUND Caffeine is widely considered to be a reinforcer in humans, but this effect is difficult to measure in non-human animals. We hypothesized that caffeine may have dual reinforcing effects comparable to nicotine--limited primary reinforcing effects, but potent reinforcement enhancing effects. The present studies tested this hypothesis by investigating the effect of caffeine on responding for non-drug rewards. METHODS In two experiments, rats were shaped to respond on a progressive ratio (PR) schedule for sucrose solution (20%, w/v; experiment 1) or a fixed ratio 2 (FR2) schedule for a moderately reinforcing visual stimulus (VS; experiment 2). Pretreatment with various doses of caffeine (0-50 mg/kg, intraperitoneal injection) were administered prior to tests over successive week days (M-F). In experiment 1, acute administration of low-moderate caffeine doses (6.25-25 mg/kg) increased responding for sucrose under the PR schedule. This effect of caffeine declined over the initial 15 test days. In experiment 2, only acute pretreatment with 12.5mg/kg caffeine increased responding for the visual stimulus and complete tolerance to this effect of caffeine was observed over the 15 days of testing. In follow up tests we found that abstinence periods of 4 and 8 days resulted in incomplete recovery of the enhancing effects of caffeine. CONCLUSION The findings suggest that caffeine enhances the reinforcing effects of non-drug stimuli, but that the pharmacological profile of these effects may differ from other psychomotor stimulants.
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Affiliation(s)
| | | | | | | | - Matthew I. Palmatier
- Corresponding Author: Matthew I. Palmatier, 469 Bluemont Hall, 1100 Mid Campus Drive, Manhattan, KS 66506,
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Keast RSJ, Sayompark D, Sacks G, Swinburn BA, Riddell LJ. The influence of caffeine on energy content of sugar-sweetened beverages: 'the caffeine-calorie effect'. Eur J Clin Nutr 2011; 65:1338-44. [PMID: 21772315 DOI: 10.1038/ejcn.2011.123] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND/OBJECTIVES Caffeine is a mildly addictive psychoactive chemical and controversial additive to sugar-sweetened beverages (SSBs). The objective of this study is to assess if removal of caffeine from SSBs allows co-removal of sucrose (energy) without affecting flavour of SSBs, and if removal of caffeine could potentially affect population weight gain. SUBJECTS/METHODS The research comprised of three studies; study 1 used three-alternate forced choice and paired comparison tests to establish detection thresholds for caffeine in water and sucrose solution (subjects, n=63), and to determine if caffeine suppressed sweetness. Study 2 (subjects, n=30) examined the proportion of sucrose that could be co-removed with caffeine from SSBs without affecting the flavour of the SSBs. Study 3 applied validated coefficients to estimate the impact on the weight of the United States population if there was no caffeine in SSBs. RESULTS Detection threshold for caffeine in water was higher (1.09 ± 0.08 mM) than the detection threshold for caffeine in sucrose solution (0.49 ± 0.04 mM), and a paired comparison test revealed caffeine significantly reduced the sweetness of sucrose (P<0.001). Removing caffeine from SSBs allowed co-removal of 10.3% sucrose without affecting flavour of the SSBs, equating to 116 kJ per 500 ml serving. The effect of this on body weight in adults and children would be 0.600 and 0.142 kg, which are equivalent to 2.08 and 1.10 years of observed existing trends in weight gain, respectively. CONCLUSION These data suggest the extra energy in SSBs as a result of caffeine's effect on sweetness may be associated with adult and child weight gain.
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Affiliation(s)
- R S J Keast
- School of Exercise and Nutrition Sciences, Deakin University, Burwood, Victoria, Australia.
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Brathwaite JM, Da Costa LA, El-Sohemy A. Catechol-O-Methyltransferase Genotype Is Associated with Self-Reported Increased Heart Rate Following Caffeine Consumption. JOURNAL OF CAFFEINE RESEARCH 2011. [DOI: 10.1089/jcr.2011.0015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Joanne M. Brathwaite
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Laura A. Da Costa
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Ahmed El-Sohemy
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, Canada
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Morelli M, Simola N. Methylxanthines and drug dependence: a focus on interactions with substances of abuse. Handb Exp Pharmacol 2011:483-507. [PMID: 20859810 DOI: 10.1007/978-3-642-13443-2_20] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This chapter examines the psychostimulant actions of methylxanthines, with a focus on the consequences of their excessive use. Consumption of methylxanthines is pervasive and their use is often associated with that of substances known to produce dependence and to have abuse potential. Therefore, the consequences of this combined use are taken into consideration in order to evaluate whether, and to what extent, methylxanthines could influence dependence on or abuse of other centrally active substances, leading to either amplification or attenuation of their effects. Since the methylxanthine that mostly influences mental processes and readily induces psychostimulation is caffeine, this review mainly focuses on caffeine as a prototype of methylxanthine-produced dependence, examining, at the same time, the risks related to caffeine use.
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Affiliation(s)
- Micaela Morelli
- Department of Toxicology, University of Cagliari, Cagliari, Italy.
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Addicott MA, Yang LL, Peiffer AM, Burnett LR, Burdette JH, Chen MY, Hayasaka S, Kraft RA, Maldjian JA, Laurienti PJ. The effect of daily caffeine use on cerebral blood flow: How much caffeine can we tolerate? Hum Brain Mapp 2009; 30:3102-14. [PMID: 19219847 DOI: 10.1002/hbm.20732] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Caffeine is a commonly used neurostimulant that also produces cerebral vasoconstriction by antagonizing adenosine receptors. Chronic caffeine use results in an adaptation of the vascular adenosine receptor system presumably to compensate for the vasoconstrictive effects of caffeine. We investigated the effects of caffeine on cerebral blood flow (CBF) in increasing levels of chronic caffeine use. Low (mean = 45 mg/day), moderate (mean = 405 mg/day), and high (mean = 950 mg/day) caffeine users underwent quantitative perfusion magnetic resonance imaging on four separate occasions: twice in a caffeine abstinent state (abstained state) and twice in a caffeinated state following their normal caffeine use (native state). In each state, there were two drug conditions: participants received either caffeine (250 mg) or placebo. Gray matter CBF was tested with repeated-measures analysis of variance using caffeine use as a between-subjects factor, and correlational analyses were conducted between CBF and caffeine use. Caffeine reduced CBF by an average of 27% across both caffeine states. In the abstained placebo condition, moderate and high users had similarly greater CBF than low users; but in the native placebo condition, the high users had a trend towards less CBF than the low and moderate users. Our results suggest a limited ability of the cerebrovascular adenosine system to compensate for high amounts of daily caffeine use.
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Affiliation(s)
- Merideth A Addicott
- Department of Radiology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA
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Temple JL. Caffeine use in children: what we know, what we have left to learn, and why we should worry. Neurosci Biobehav Rev 2009; 33:793-806. [PMID: 19428492 PMCID: PMC2699625 DOI: 10.1016/j.neubiorev.2009.01.001] [Citation(s) in RCA: 189] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2008] [Revised: 01/12/2009] [Accepted: 01/12/2009] [Indexed: 12/30/2022]
Abstract
Caffeine is a widely used psychoactive substance in both adults and children that is legal, easy to obtain, and socially acceptable to consume. Although once relatively restricted to use among adults, caffeine-containing drinks are now consumed regularly by children. In addition, some caffeine-containing beverages are specifically marketed to children as young as 4 years of age. Unfortunately, our knowledge of the effects of caffeine use on behavior and physiology of children remains understudied and poorly understood. The purpose of this article is to review what is known about caffeine use in children and adolescents, to discuss why children and adolescents may be particularly vulnerable to the negative effects of caffeine, and to propose how caffeine consumption within this population may potentiate the rewarding properties of other substances. The following topics are reviewed: (1) tolerance and addiction to caffeine, (2) sensitization and cross-sensitization to the effects of caffeine, (3) caffeine self-administration and reinforcing value, and (4) conditioning of preferences for caffeine-containing beverages in both adults and children.
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Affiliation(s)
- Jennifer L Temple
- University at Buffalo, Department of Exercise and Nutrition Sciences, Buffalo, NY 14214, USA.
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Gummadi SN, Ganesh K, Santhosh D. Enhanced degradation of caffeine by immobilized cells of Pseudomonas sp. in agar–agar matrix using statistical approach. Biochem Eng J 2009. [DOI: 10.1016/j.bej.2008.11.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Addicott MA, Yang LL, Peiffer AM, Laurienti PJ. Methodological considerations for the quantification of self-reported caffeine use. Psychopharmacology (Berl) 2009; 203:571-8. [PMID: 19011837 PMCID: PMC2829439 DOI: 10.1007/s00213-008-1403-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2008] [Accepted: 10/29/2008] [Indexed: 10/21/2022]
Abstract
RATIONALE The field of research regarding the effects of habitual caffeine use is immense and frequently utilizes self-report measures of caffeine use. However, various self-report measures have different methodologies, and the accuracy of these different methods has not been compared. MATERIALS AND METHODS Self-reported caffeine use was estimated from two methods (a retrospective interview of weekly caffeine use and a 7-day prospective diary; n = 79). These estimates were then tested against salivary caffeine concentrations in a subset of participants (n = 55). RESULTS The estimates of caffeine use (mg/day) from the interview- and diary-based methods correlated with one another (r = 0.77) and with salivary caffeine concentrations (r = 0.61 and 0.68, respectively). However, almost half of the subjects who reported more than 600 mg/day in the interview reported significantly less caffeine use in the diary. CONCLUSIONS Self-report measures of caffeine use are a valid method of predicting actual caffeine levels. Estimates of high caffeine use levels may need to be corroborated by more than one method.
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Caffeine reinforces flavor preference and behavior in moderate users but not in low caffeine users. LEARNING AND MOTIVATION 2009. [DOI: 10.1016/j.lmot.2008.05.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Abstract
Caffeine is the most widely consumed psychostimulant drug in the world. With intermittent exposures, caffeine may act as a mild analgesic for headache or as an adjuvant for the actions of other analgesics. Chronic repetitive exposures to caffeine increase the risks for development of analgesic-overuse headache, chronic daily headache, and physical dependency. Cessation of caffeine use after chronic exposures leads to a withdrawal syndrome with headache as a dominant symptom. At dosages achieved by common dietary intake, caffeine acts as a potent antagonist of central and peripheral nervous system adenosine receptors. The complex effects of caffeine on headache disorders suggest important roles for adenosine in these disorders and in the induction of caffeine dependency.
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Affiliation(s)
- Robert E Shapiro
- Department of Neurology, Given C219B, University of Vermont College of Medicine, 89 Beaumont Avenue, Burlington, VT 05405, USA.
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Lau-Barraco C, Schmitz JM. Drug preference in cocaine and alcohol dual-dependent patients. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 2008; 34:211-7. [PMID: 18293238 DOI: 10.1080/00952990701877136] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The present study extended previous work with the multiple-choice procedure (MCP) by examining the monetary value of cocaine and alcohol in dual-dependent patients. Participants made hypothetical choices between pairs of substances and between each substance and a series of monetary values. Results showed that the combination of cocaine and alcohol was preferred over each individual substance. The monetary value at which the substance is no longer chosen was higher for the combination than for one drink or one hit alone. Monetary values showed convergence with dependence-related variables. These findings substantiate the importance of concurrent alcohol and cocaine dependence treatment.
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Affiliation(s)
- Cathy Lau-Barraco
- Research Institute on Addictions, University at Buffalo, Buffalo, New York 14203-1016, USA.
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Greenwald MK. Behavioral economic analysis of drug preference using multiple choice procedure data. Drug Alcohol Depend 2008; 93:103-10. [PMID: 17949924 PMCID: PMC2248460 DOI: 10.1016/j.drugalcdep.2007.09.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2007] [Revised: 09/07/2007] [Accepted: 09/10/2007] [Indexed: 11/19/2022]
Abstract
The multiple choice procedure has been used to evaluate preference for psychoactive drugs, relative to money amounts (price), in human subjects. The present re-analysis shows that MCP data are compatible with behavioral economic analysis of drug choices. Demand curves were constructed from studies with intravenous fentanyl, intramuscular hydromorphone and oral methadone in opioid-dependent individuals; oral d-amphetamine, oral MDMA alone and during fluoxetine treatment, and smoked marijuana alone or following naltrexone pretreatment in recreational drug users. For each participant and dose, the MCP crossover point was converted into unit price (UP) by dividing the money value ($) by the drug dose (mg/70kg). At the crossover value, the dose ceases to function as a reinforcer, so "0" was entered for this and higher UPs to reflect lack of drug choice. At lower UPs, the dose functions as a reinforcer and "1" was entered to reflect drug choice. Data for UP vs. average percent choice were plotted in log-log space to generate demand functions. Rank of order of opioid inelasticity (slope of non-linear regression) was: fentanyl>hydromorphone (continuing heroin users)>methadone>hydromorphone (heroin abstainers). Rank order of psychostimulant inelasticity was d-amphetamine>MDMA>MDMA+fluoxetine. Smoked marijuana was more inelastic with high-dose naltrexone. These findings show this method translates individuals' drug preferences into estimates of population demand, which has the potential to yield insights into pharmacotherapy efficacy, abuse liability assessment, and individual differences in susceptibility to drug abuse.
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Affiliation(s)
- Mark K Greenwald
- Substance Abuse Research Division, Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI, USA.
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Abstract
Caffeine is one of the most widely consumed psychoactive substances and it has profound effects on sleep and wake function. Laboratory studies have documented its sleep-disruptive effects. It clearly enhances alertness and performance in studies with explicit sleep deprivation, restriction, or circadian sleep schedule reversals. But, under conditions of habitual sleep the evidence indicates that caffeine, rather then enhancing performance, is merely restoring performance degraded by sleepiness. The sleepiness and degraded function may be due to basal sleep insufficiency, circadian sleep schedule reversals, rebound sleepiness, and/or a withdrawal syndrome after the acute, over-night, caffeine discontinuation typical of most studies. Studies have shown that caffeine dependence develops at relatively low daily doses and after short periods of regular daily use. Large sample and population-based studies indicate that regular daily dietary caffeine intake is associated with disturbed sleep and associated daytime sleepiness. Further, children and adolescents, while reporting lower daily, weight-corrected caffeine intake, similarly experience sleep disturbance and daytime sleepiness associated with their caffeine use. The risks to sleep and alertness of regular caffeine use are greatly underestimated by both the general population and physicians.
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Sigmon SC. Investigating the pharmacological and nonpharmacological factors that modulate drug reinforcement. Exp Clin Psychopharmacol 2007; 15:1-20. [PMID: 17295581 DOI: 10.1037/1064-1297.15.1.1] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Drug use is driven by principles of reinforcement and is sensitive to influences in the environmental context in which it occurs. Although a wide range of factors has been shown to directly influence the reinforcing effects of commonly abused drugs, 2 general types include pharmacological and nonpharmacological factors. Both can assert a powerful impact on a drug's reinforcing effects and, therefore, the degree to which a particular drug comes to be used and abused. This invited review seeks to briefly describe some of the current psychopharmacology research on the interactions between these factors and drug abuse. Several pharmacological influences on drug use will be discussed, including the interactions between psychomotor stimulants and recent advances in the development of pharmacotherapies for opioid abuse. With regard to nonpharmacological factors, there is a large body of research demonstrating that nondrug reinforcers can exert a powerful influence on the reinforcing effects of commonly abused drugs. More specifically, identifying alternative nondrug sources of reinforcement can, if made available contingent on drug abstinence, produce robust decreases in drug self-administration. Presented here is a very brief review of some recent scientific efforts to develop and extend behavioral interventions targeting drug use across a wide range of clinical populations. In summary, understanding the interactions among the variables present in the context of drug use is critical to understanding risk factors for substance use disorders as well as developing efficacious treatments for drug dependence.
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Keast RSJ, Riddell LJ. Caffeine as a flavor additive in soft-drinks. Appetite 2006; 49:255-9. [PMID: 17189661 DOI: 10.1016/j.appet.2006.11.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2006] [Revised: 11/15/2006] [Accepted: 11/20/2006] [Indexed: 10/23/2022]
Abstract
Over 60% of soft-drinks sold in the United States contain caffeine, a mildly addictive psycho-active chemical, as a flavor additive. Using sweeteners as controls, we assessed whether caffeine has flavor activity in a cola soft-drink. A forced-choice triangle discrimination methodology was used to determine detection thresholds of caffeine in sweeteners and a cola beverage. The subjects (n=30, 28 female, 23+/-4 years old) were trained tasters and completed over 1600 discrimination tests during the study. The mean detection thresholds for caffeine in the sweet solutions were: 0.333+/-0.1mM sucrose; 0.467+/-0.29 mM aspartame; 0.462+/-0.3mM sucralose, well below the concentration in common cola beverages (0.55-0.67 mM). A fixed concentration of caffeine, corresponding to the concentration of caffeine in a common cola beverage (0.67 mM) was added to the sweeteners and a non-caffeinated cola beverage. Subjects could distinguish between caffeinated and non-caffeinated sweeteners (p<0.001), but all subjects failed to distinguish between caffeinated and non-caffeinated cola beverage (p=1.0). Caffeine has no flavor activity in soft-drinks yet will induce a physiologic and psychologic desire to consume the drink.
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Affiliation(s)
- Russell S J Keast
- School of Exercise and Nutrition Sciences, Deakin University, 221 Burwood Highway, Burwood, Victoria 3125, Australia.
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Martin PY, Hamilton VE, McKimmie BM, Terry DJ, Martin R. Effects of caffeine on persuasion and attitude change: The role of secondary tasks in manipulating systematic message processing. EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY 2006. [DOI: 10.1002/ejsp.347] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Norager CB, Jensen MB, Madsen MR, Laurberg S. Caffeine improves endurance in 75-yr-old citizens: a randomized, double-blind, placebo-controlled, crossover study. J Appl Physiol (1985) 2005; 99:2302-6. [PMID: 16081625 DOI: 10.1152/japplphysiol.00309.2005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This study investigated the effect of caffeine on physical performance in healthy citizens aged > or =70 yr. The randomized, double-blind, placebo-controlled, crossover study was conducted in 15 men and 15 women recruited by their general practitioner. Participants abstained from caffeine for 48 h and were randomized to receive one capsule of placebo and then caffeine (6 mg/kg) or caffeine and then placebo with 1 wk in between. One hour after intervention, we measured reaction and movement times, postural stability, walking speed, cycling at 65% of expected maximal heart rate, perceived effort during cycling, maximal isometric arm flexion strength, and endurance. Analysis was by intention to treat, and P < 0.05 was regarded as significant. Caffeine increased cycling endurance by 25% [95% confidence interval (CI): 13-38; P = 0.0001] and isometric arm flexion endurance by 54% (95% CI: 29-83; P = 0.0001). Caffeine also reduced the rating of perceived exertion after 5 min of cycling by 11% (95% CI: 5-17; P = 0.002) and postural stability with eyes open by 25% (95% CI: 2-53; P = 0.03). Caffeine ingestion did not affect muscle strength, walking speed, reaction, and movement times. At the end of the study, 46% of participants correctly identified when they received caffeine and placebo. Caffeine increased exercise endurance in healthy citizens aged > or =70 yr, but the participants' reasons for stopping the test may have varied between subjects, as the cycling test was done at approximately 55% of maximal oxygen consumption. Further studies are required to investigate whether caffeine can be utilized to improve the physical performance of elderly citizens.
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Affiliation(s)
- C B Norager
- Surgical Research Unit, Dept. of Surgery, Herning Hospital, University Hospital of Aarhus, Denmark.
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Gokulakrishnan S, Chandraraj K, Gummadi SN. Microbial and enzymatic methods for the removal of caffeine. Enzyme Microb Technol 2005. [DOI: 10.1016/j.enzmictec.2005.03.004] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Juliano LM, Griffiths RR. A critical review of caffeine withdrawal: empirical validation of symptoms and signs, incidence, severity, and associated features. Psychopharmacology (Berl) 2004; 176:1-29. [PMID: 15448977 DOI: 10.1007/s00213-004-2000-x] [Citation(s) in RCA: 309] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2004] [Accepted: 07/24/2004] [Indexed: 11/30/2022]
Abstract
RATIONALE Although reports of caffeine withdrawal in the medical literature date back more than 170 years, the most rigorous experimental investigations of the phenomenon have been conducted only recently. OBJECTIVES The purpose of this paper is to provide a comprehensive review and analysis of the literature regarding human caffeine withdrawal to empirically validate specific symptoms and signs, and to appraise important features of the syndrome. METHODS A literature search identified 57 experimental and 9 survey studies on caffeine withdrawal that met inclusion criteria. The methodological features of each study were examined to assess the validity of the effects. RESULTS Of 49 symptom categories identified, the following 10 fulfilled validity criteria: headache, fatigue, decreased energy/activeness, decreased alertness, drowsiness, decreased contentedness, depressed mood, difficulty concentrating, irritability, and foggy/not clearheaded. In addition, flu-like symptoms, nausea/vomiting, and muscle pain/stiffness were judged likely to represent valid symptom categories. In experimental studies, the incidence of headache was 50% and the incidence of clinically significant distress or functional impairment was 13%. Typically, onset of symptoms occurred 12-24 h after abstinence, with peak intensity at 20-51 h, and for a duration of 2-9 days. In general, the incidence or severity of symptoms increased with increases in daily dose; abstinence from doses as low as 100 mg/day produced symptoms. Research is reviewed indicating that expectancies are not a prime determinant of caffeine withdrawal and that avoidance of withdrawal symptoms plays a central role in habitual caffeine consumption. CONCLUSIONS The caffeine-withdrawal syndrome has been well characterized and there is sufficient empirical evidence to warrant inclusion of caffeine withdrawal as a disorder in the DSM and revision of diagnostic criteria in the ICD.
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Affiliation(s)
- Laura M Juliano
- Department of Psychology, American University, 4400 Massachusetts Avenue, Washington, DC 20016, USA
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Sobel BFX, Sigmon SC, Griffiths RR. Transdermal nicotine maintenance attenuates the subjective and reinforcing effects of intravenous nicotine, but not cocaine or caffeine, in cigarette-smoking stimulant abusers. Neuropsychopharmacology 2004; 29:991-1003. [PMID: 15010695 DOI: 10.1038/sj.npp.1300415] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The effects of transdermal nicotine maintenance on the subjective, reinforcing, and cardiovascular effects of intravenously administered cocaine, caffeine, and nicotine were examined using double-blind procedures in nine volunteers with histories of using tobacco, caffeine, and cocaine. Each participant was exposed to two chronic drug maintenance phases (21 mg/day nicotine transdermal patch and placebo transdermal patch). Within each drug phase, the participant received intravenous injections of placebo, cocaine (15 and 30 mg/70 kg), caffeine (200 and 400 mg/70 kg), and nicotine (1.0 and 2.0 mg/70 kg) in mixed order across days. Subjective and cardiovascular data were collected before and repeatedly after drug or placebo injection. Reinforcing effects were also assessed after each injection with a Drug vs Money Multiple-Choice Form. Intravenous cocaine produced robust dose-related increases in subjective and reinforcing effects; these effects were not altered by nicotine maintenance. Intravenous caffeine produced elevations on several subjective ratings; nicotine maintenance did not affect these ratings. Under the placebo maintenance condition, intravenous nicotine produced robust dose-related subjective effects, with maximal increases similar to the high dose of cocaine; nicotine maintenance significantly decreased the subjective and reinforcing effects of intravenous nicotine. The results of the present study demonstrate that chronic nicotine maintenance produces tolerance to the effects of intravenous nicotine, but does not affect the subjective or reinforcing effects of cocaine or caffeine.
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Affiliation(s)
- Bai-Fang X Sobel
- Department of Psychiatry and Behavioral Science, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA
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Smith B, Osborne A, Jones H, White T, Mann M. Arousal and Behavior. NUTRITION, BRAIN AND BEHAVIOR 2004. [DOI: 10.1201/9780203618851.ch3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Abstract
This paper describes the rationale and procedures for conducting what is considered by many to be the current "gold standard" for initial abuse liability testing of a novel compound: the classic acute dose-effect comparison study in volunteers with histories of drug abuse. Such a trial is most appropriate for predicting the likelihood of abuse by drug abusers and, in turn, the extent of drug diversion and illicit street sales if the novel compound became available in the community. The dose-effect abuse liability trial typically involves a double-blind complete crossover design in 10-14 subjects with histories of polydrug abuse in a controlled clinical pharmacology laboratory setting. Drug conditions usually involve placebo, three doses of the novel compound and three doses of an appropriate reference compound of known abuse liability. In each session, the time-course of effects of a single drug dose are evaluated. Intervals between experimental sessions are typically 1 to several days. The importance of testing high supra-therapeutic doses of the novel drug for the validity of the trial is emphasized, and the use of a dose run-up pilot study for selecting maximal doses and matching doses between the novel and comparison compound is explained. The rationale and description of outcome measures is discussed, including measures that reflect likelihood of abuse (e.g. drug vs. money choice and subject ratings of liking, good effects, estimated monetary street value), secondary measures that should be considered in interpreting likelihood of abuse (e.g. drug identification, subject-rated side effects and mood changes), and additional concurrent measures to establish equivalence of the novel and comparison compound (e.g. behavioral performance, observer-rated assessments, physiological measures).
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Affiliation(s)
- Roland R Griffiths
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, 5510 Nathan Shock Drive, Baltimore, MD 21224, USA.
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Tinley EM, Yeomans MR, Durlach PJ. Caffeine reinforces flavour preference in caffeine-dependent, but not long-term withdrawn, caffeine consumers. Psychopharmacology (Berl) 2003; 166:416-23. [PMID: 12589525 DOI: 10.1007/s00213-002-1354-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2002] [Accepted: 11/14/2002] [Indexed: 10/20/2022]
Abstract
RATIONALE Previous studies have shown that caffeine can reinforce flavour liking in overnight deprived moderate caffeine consumers (e.g. average of 250 mg/day) but not in low consumers (<120 mg/day). However, it is not possible to determine whether the difference between moderate and low caffeine consumers results from pre-existing individual differences in response to caffeine, or results directly from the different amounts of caffeine they habitually consume. If the former were true, then moderate consumers who are completely withdrawn should still manifest the flavour conditioning effect. Conversely, if the latter were true, consumers who are completely withdrawn should not manifest the effect. OBJECTIVES To examine whether moderate caffeine consumers who have been fully withdrawn from caffeine manifest the flavour conditioning effect. METHODS In a double-blind study, 48 moderate caffeine consumers refrained from consuming caffeine for 4 weeks and were given replacement drinks to consume, which were either caffeinated (maintained group) or decaffeinated (withdrawn group). In the final 2 weeks, all subjects evaluated a novel drink containing either 100 mg caffeine or placebo on four non-consecutive days. RESULTS. The rated pleasantness of the novel drink containing caffeine increased over the four test days in the group maintained on caffeine, but pleasantness of the same drink fell significantly in the withdrawn group. CONCLUSIONS These data suggest that the ability of caffeine to reinforce changes in flavour liking are driven by the alleviation of withdrawal symptoms among habitual caffeine consumers and provide further support for the negative reinforcement theory.
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Affiliation(s)
- Elizabeth M Tinley
- Departmemnt of Experimental Psychology, University of Sussex, BN1 9QG, Brighton, UK
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Rogers PJ, Martin J, Smith C, Heatherley SV, Smit HJ. Absence of reinforcing, mood and psychomotor performance effects of caffeine in habitual non-consumers of caffeine. Psychopharmacology (Berl) 2003; 167:54-62. [PMID: 12601503 DOI: 10.1007/s00213-002-1360-3] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2002] [Accepted: 11/14/2002] [Indexed: 10/20/2022]
Abstract
RATIONALE The extent to which the measured (and felt) psychostimulant effects of caffeine represent a real benefit of caffeine consumption or merely withdrawal reversal is unclear. Results showing positive psychostimulant effects of acute caffeine administration in habitual non-consumers of caffeine would provide evidence for a net benefit of caffeine unconfounded by withdrawal. OBJECTIVES To compare the mood, alerting, psychomotor and reinforcing effects of caffeine in caffeine non-consumers and acutely (overnight) withdrawn caffeine consumers. METHODS In experiment 1, these participants consumed two differently flavoured drinks, one containing 100 mg caffeine and the other containing no caffeine. Each drink was consumed on 4 separate days in semi-random order, and self-ratings of mood and alertness were completed before and after drink consumption. On day 9, both drinks contained 50 mg caffeine and drink preference (choice) and intake were assessed. In experiment 2, mood, alertness and performance on a long-duration simple reaction time task were assessed before and after administration of 100 mg or placebo in a single test session. RESULTS Prior to receiving caffeine, the (overnight withdrawn) caffeine consumers were less alert and more tense than the non-consumers. Caffeine only had significant reinforcing, mood and psychomotor performance effects in the caffeine consumers. The reinforcing effect of caffeine was evident from an effect on drink intake, but drink choice was unaffected. Caffeine increased self-rated alertness of both caffeine consumers and non-consumers; however, for some of the non-consumers this was associated with a worsening of performance. CONCLUSIONS These results support the hypothesis that the psychostimulant and related effects of caffeine are due largely to withdrawal reversal.
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Affiliation(s)
- Peter J Rogers
- Department of Experimental Psychology, University of Bristol, 8 Woodland Road, BS8 1TN, Bristol, UK.
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44
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Abstract
OBJECTIVES With reports of high rates of sleep disruption in Human Immunodeficiency Virus (HIV) + persons, this study tested whether there were differences in sleep quality and well-being between a group of HIV+ persons who reduced their caffeine intake from baseline by 90% or greater for 30 days (n=44) versus a group of HIV+ persons who continued their usual caffeine consumption (n=44). METHODS Subjects were administered pre- and post-Pittsburgh Sleep Quality Index (PSQI), Perceived Well-being Scale-Revised (PWB-R) and MOS-HIV Health Survey instruments, with MOS-HIV summary scores used as a covariate. RESULTS On ANCOVA analysis for sleep quality (F=14.032, P<.001), a 35% improvement in sleep among experimental subjects was identified. There was no significant difference between the two groups on ANCOVA analysis for well-being (F=0.111. P=.739). CONCLUSIONS High levels of caffeine consumption may have an exacerbating effect on already prevalent HIV-related sleep pattern disturbances, and significant reductions of caffeine may improve sleep quality.
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Affiliation(s)
- H Michael Dreher
- School of Nursing, University of Pennsylvania, Philadelphia, USA.
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Abstract
The literature suggests that the following effects on behavior of adult humans may occur when individuals consume moderate amounts of caffeine. (1) Caffeine increases alertness and reduces fatigue. This may be especially important in low arousal situations (e.g. working at night). (2) Caffeine improves performance on vigilance tasks and simple tasks that require sustained response. Again, these effects are often clearest when alertness is reduced, although there is evidence that benefits may still occur when the person is unimpaired. (3) Effects on more complex tasks are difficult to assess and probably involve interactions between the caffeine and other variables which increase alertness (e.g. personality and time of day). (4) In contrast to the effects of caffeine consumption, withdrawal of caffeine has few effects on performance. There is often an increase in negative mood following withdrawal of caffeine, but such effects may largely reflect the expectancies of the volunteers and the failure to conduct "blind" studies. (5) Regular caffeine usage appears to be beneficial, with higher users having better mental functioning. (6) Most people are very good at controlling their caffeine consumption to maximise the above positive effects. For example, the pattern of consumption over the day shows that caffeine is often consumed to increase alertness. Indeed, many people do not consume much caffeine later in the day since it is important not to be alert when one goes to sleep. In contrast to effects found from normal caffeine intake, there are reports that have demonstrated negative effects when very large amounts are given or sensitive groups (e.g. patients with anxiety disorders) were studied. In this context caffeine has been shown to increase anxiety and impair sleep. There is also some evidence that fine motor control may be impaired as a function of the increase in anxiety. Overall, the global picture that emerges depends on whether one focuses on effects that are likely to be present when caffeine is consumed in moderation by the majority of the population or on the effects found in extreme conditions. The evidence clearly shows that levels of caffeine consumed by most people have largely positive effects on behavior. Excessive consumption can lead to problems, especially in sensitive individuals.
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Affiliation(s)
- A Smith
- Center for Occupational and Health Psychology, School of Psychology, Cardiff University, UK.
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46
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Abstract
Caffeine has been an additive in analgesics for many years. However, the analgesic adjuvant effects of caffeine have not been seriously investigated since a pooled analysis conducted in 1984 showed that caffeine reduces the amount of paracetamol (acetaminophen) necessary for the same effect by approximately 40%. In vitro and in vivo pharmacological research has provided some evidence that caffeine can have anti-nociceptive actions through blockade of adenosine receptors, inhibition of cyclo-oxygenase-2 enzyme synthesis, or by changes in emotion state. Nevertheless, these actions are only considered in some cases. It is suggested that the actual doses of analgesics and caffeine used can influence the analgesic adjuvant effects of caffeine, and doses that are either too low or too high lead to no analgesic enhancement. Clinical trials suggest that caffeine in doses of more than 65 mg may be useful for enhancement of analgesia. However, except for in headache pain, the benefits are equivocal. While adding caffeine to analgesics increases the number of patients who become free from headache [rate ratio = 1.36, 95% confidence interval (CI) 1.17 to 1.58], it also leads to more patients with nervousness and dizziness (relative risk = 1.60, 95% CI 1.26 to 2.03). It is suggested that long-term use or overuse of analgesic medications is associated with rebound headache. However, there is no robust evidence that headache after use or withdrawal of caffeine-containing analgesics is more frequent than after other analgesics. Case-control studies have shown that caffeine-containing analgesics are associated with analgesic nephropathy (odds ratio = 4.9, 95% CI 2.3 to 10.3). However, no specific contribution of caffeine to analgesic nephropathy can be identified from these studies. Whether caffeine produces nephrotoxicity on its own, or increases nephrotoxicity due to analgesics, is yet to be established.
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Affiliation(s)
- W Y Zhang
- Centre for Evidence-Based Pharmacotherapy, Pharmaceutical Sciences, Aston University, Birmingham, UK.
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48
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Abstract
Caffeine is the most widely used psychoactive substance and has been considered occasionally as a drug of abuse. The present paper reviews available data on caffeine dependence, tolerance, reinforcement and withdrawal. After sudden caffeine cessation, withdrawal symptoms develop in a small portion of the population but are moderate and transient. Tolerance to caffeine-induced stimulation of locomotor activity has been shown in animals. In humans, tolerance to some subjective effects of caffeine seems to occur, but most of the time complete tolerance to many effects of caffeine on the central nervous system does not occur. In animals, caffeine can act as a reinforcer, but only in a more limited range of conditions than with classical drugs of dependence. In humans, the reinforcing stimuli functions of caffeine are limited to low or rather moderate doses while high doses are usually avoided. The classical drugs of abuse lead to quite specific increases in cerebral functional activity and dopamine release in the shell of the nucleus accumbens, the key structure for reward, motivation and addiction. However, caffeine doses that reflect the daily human consumption, do not induce a release of dopamine in the shell of the nucleus accumbens but lead to a release of dopamine in the prefrontal cortex, which is consistent with caffeine reinforcing properties. Moreover, caffeine increases glucose utilization in the shell of the nucleus accumbens only at rather high doses that stimulate most brain structures, non-specifically, and likely reflect the side effects linked to high caffeine ingestion. That dose is also 5-10-fold higher than the one necessary to stimulate the caudate nucleus, which mediates motor activity and the structures regulating the sleep-wake cycle, the two functions the most sensitive to caffeine. In conclusion, it appears that although caffeine fulfils some of the criteria for drug dependence and shares with amphetamines and cocaine a certain specificity of action on the cerebral dopaminergic system, the methylxanthine does not act on the dopaminergic structures related to reward, motivation and addiction.
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Affiliation(s)
- A Nehlig
- INSERM U 398, Faculté de Médecine, Strasbourg, France.
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Abstract
Caffeine has both positive effects that contribute to widespread consumption of caffeine-containing beverages and adverse unpleasant effects if doses are increased. Caffeine has weak reinforcing properties, but with little or no evidence for upward dose adjustment, possibly because of the adverse effects of higher doses. Withdrawal symptoms, although relatively limited with respect to severity, do occur, and may contribute to maintenance of caffeine consumption. Health hazards are small if any and caffeine use is not associated with incapacitation. Thus, although caffeine can be argued to fulfill regulatory criteria as a dependence-producing drug, the extensive use of caffeine-containing beverages poses little apparent risk to the consumer or to society. The positive stimulatory effects of caffeine appear in large measure to be due to blockade of A2A receptors that stimulate GABAergic neurons of inhibitory pathways to the dopaminergic reward system of the striatum. However, blockade of striatal A1 receptors may also play a role. The mechanisms underlying negative effects of higher doses of caffeine are as yet not well defined.
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Affiliation(s)
- J W Daly
- Laboratory of Bioorganic Chemistry, National Institutes of Health, Bethesda, MD 20892, USA
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50
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Rogers PJ, Dernoncourt C. Regular caffeine consumption: a balance of adverse and beneficial effects for mood and psychomotor performance. Pharmacol Biochem Behav 1998; 59:1039-45. [PMID: 9586865 DOI: 10.1016/s0091-3057(97)00515-7] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
It has often been pointed out that caffeine is the most widely "used" psychoactive substance in the world, and accordingly, there is a very large amount of research available on the effects of caffeine on body and mind. In particular, a psychostimulant action of caffeine is generally accepted as well established; for example, caffeine has been found to quicken reaction time and enhance vigilance performance, and to increase self-rated alertness and improve mood. There is, however, a real difficulty in determining the net effects of caffeine. In a typical experiment the subjects have a history of regular caffeine consumption, and they are tested on caffeine and a placebo after a period of caffeine deprivation (often overnight). The problem with relying solely on this approach is that it leaves open the question as to whether the results obtained are due to beneficial effects of caffeine or to deleterious effects of caffeine deprivation. The present article briefly reviews this evidence on the psychostimulant effects of caffeine, and presents some new data testing the hypothesis that caffeine may enhance cognitive performance to a greater extent in older adults than in young adults. No age-related differences in the effects of caffeine on psychomotor performance were found. We conclude that overall there is little unequivocal evidence to show that regular caffeine use is likely to substantially benefit mood or performance. Indeed, one of the significant factors motivating caffeine consumption appears to be "withdrawal relief."
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Affiliation(s)
- P J Rogers
- Consumer Sciences Department, Institute of Food Research, Reading Laboratory, UK
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