20 resultados para Cravings
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This study examined effects of 12 weeks of moderate-intensity aerobic exercise on eating behaviour, food cravings and weekly energy intake and expenditure in inactive men. Eleven healthy men (mean ± SD: age, 26 ± 5 years; body mass index, 24.6 ± 3.8 kg/m2; maximum oxygen uptake, 43.1 ± 7.4 mL/kg/min) completed the 12-week supervised exercise programme. Body composition, health markers (e.g. blood pressure), eating behaviour, food cravings and weekly energy intake and expenditure were assessed before and after the exercise intervention. There were no intervention effects on weekly free-living energy intake (p=0.326, d=-0.12) and expenditure (p=0.799, d=0.04), or uncontrolled eating and emotional eating scores (p>0.05). However, there was a trend with a medium effect size (p=0.058, d=0.68) for cognitive restraint to be greater after the exercise intervention. Total food cravings (p=0.009, d=-1.19) and specific cravings of high-fat foods (p=0.023, d=-0.90), fast-food fats (p=0.009, d=-0.71) and carbohydrates/starches (p=0.009, d=-0.56) decreased from baseline to 12 weeks. Moreover, there was a trend with a large effect size for cravings of sweets (p=0.052, d=-0.86) to be lower after the exercise intervention. In summary, 12 weeks of moderate-intensity aerobic exercise reduced food cravings and increased cognitive restraint, however, these were not accompanied by changes in other eating behaviours and weekly energy intake and expenditure. The results indicate the importance of exercising for health improvements even when reductions in body mass are modest.
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The thesis of this book is that there are connections between eating disorders and substance abuse. There are similarities in the craving for food to the cravings for substances of addiction; people with eating disorders experience symptoms similar to those of classic addiction. With the increase in obesity in the West, this book hopes to focus future studies on more effective treatment.This resource was contributed by The National Documentation Centre on Drug Use.
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OBJECTIVE: To assess the impact of instructional guidance in the regular use of use nicotine nasal spray (NNS) on the true use of NNS during the first three weeks of smoking cessation for heavy smokers who are willing to quit. METHODS: This randomized, open, controlled trial included 50 patients who were heavy smokers, were willing to quit, and attending an academic outpatient clinic in Western Switzerland. Patients were randomised to instruction on NNS use as "ad libitum" (administration whenever cravings appear; control group) or to use NNS when craving appears and at least every hour when awake (intervention group). Intakes were monitored using an electronic device fixed in the spray unit (MDILog) during the first three weeks of use. Self reported abstinence from smoking at six months was confirmed by expired-air carbon monoxide. Using intention-to-treat analysis, random-effect GLS regression was used to calculate the mean difference of daily doses between groups controlling for lack of independence between measures from the same individual. RESULTS: One patient was lost to follow-up. At baseline randomization, the group receiving instruction to use NNS hourly included more women, patients with previous desires to quit, and patients with more psychiatric comorbidities and less somatic complaints compared to the group instructed to use NNS with cravings (group imbalance). Both groups self-administered more than the daily recommended dosage of 8 uses. Mean daily usage was 13.6 dose/day and 11.1 dose/day for the group instructed to use NNS hourly and with cravings, respectively. Adjusting for baseline imbalance, the increased daily doses in the intervention group (hourly use) remained nonsignificant compared to ad libitum use (-0.5 dose/day; CI 95% -6.2; 5.3, from day 1 to day 7; and 2.3 dose/day; CI 95% -5.4; 10.0, from day 8 to day 21). Instructing patients to use the NNS daily had no effect on smoking cessation at six months (RR = 0.69; CI 95% 0.34; 1.39). CONCLUSION: Heavy smokers willing to quit use NNS frequently, regardless of the instructions given. Recommending the use of NNS only when craving appears for heavy smokers willing to quit seems acceptable compared to prescribing hourly administration. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00861276.
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Water deprivation-induced thirst is explained by the double-depletion hypothesis, which predicts that dehydration of the two major body fluid compartments, the extracellular and intracellular compartments, activates signals that combine centrally to induce water intake. However, sodium appetite is also elicited by water deprivation. In this brief review, we stress the importance of the water-depletion and partial extracellular fluid-repletion protocol which permits the distinction between sodium appetite and thirst. Consistent enhancement or a de novo production of sodium intake induced by deactivation of inhibitory nuclei (e.g., lateral parabrachial nucleus) or hormones (oxytocin, atrial natriuretic peptide), in water-deprived, extracellular-dehydrated or, contrary to tradition, intracellular-dehydrated rats, suggests that sodium appetite and thirst share more mechanisms than previously thought. Water deprivation has physiological and health effects in humans that might be related to the salt craving shown by our species.
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Contexte : Jusqu’à 90% des fumeurs qui tentent d’arrêter de fumer vont rechuter dans l’année suivant la date d’arrêt. L’impulsivité, au même titre que le « craving », a démontré être un bon facteur de prédiction de la rechute tabagique. Ainsi, la présente étude visait à évaluer, à l’aide de la neuroimagerie fonctionnelle, l’influence de l’impulsivité sur les mécanismes neuronaux du « craving » de la cigarette. Parmi les régions cérébrales impliquées dans le « craving » de la nicotine, les cortex préfrontal dorsolatéral, orbitofrontal et cingulaire sont d’importantes structures dans les processus de contrôle de soi. Méthodes : 31 fumeurs chroniques ont passé une session de neuroimagerie durant laquelle ils devaient regarder des images appétitives de cigarettes et des images neutres. Ils ont ensuite dû inscrire le « craving » ressenti à la vue des images et répondre à un questionnaire portant sur les traits de personnalité de l’impulsivité (BIS-11). Résultats : Tel qu’attendu, le score d’impulsivité était positivement corrélé au « craving » rapporté par les participants à la vue d’images de cigarettes. Au niveau cérébral, plus les fumeurs présentaient de forts traits d’impulsivité, moins grande était l’activité du cortex cingulaire postérieur (CCP) durant le « craving ». Enfin, l’activité du CCP présentait une connectivité fonctionnelle négative avec l’insula, le cortex préfrontal dorsolatéral et le cortex cingulaire antérieur. Conclusions : Comme le CCP est le siège des processus de mentalisation et de référence à soi, nous suggérons que plus les fumeurs étaient impulsifs, moins ils prenaient conscience de leur état et moins ils en exerçaient un contrôle, donc plus ils ressentaient de forts « cravings ». En poussant plus loin, nos résultats mettent l’accent sur l’aspect identitaire (le soi, les mémoires autobiographiques) et l’aspect d’introspection en toxicomanie : deux avenues à explorer.
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Contexte: Plusieurs études ont démontré que les indices environnementaux associés à la cigarette peuvent provoquer des envies de consommer (« cravings ») chez les fumeurs, ce qui nuit aux efforts d’abandon de la substance et favorise le maintien du tabagisme. Un bon nombre d’études en imagerie cérébrale ont examiné les bases neurophysiologiques de cette caractéristique clinique. Le tabagisme se caractérise aussi par l’incapacité des représentations négatives de la consommation (méfaits médicaux et sociaux) d’influencer la consommation des fumeurs. Étonnamment toutefois, très peu de travaux de recherche se sont intéressés à examiner les bases neurophysiologiques de cette insouciance envers les méfaits de la cigarette chez les fumeurs. En utilisant l'imagerie cérébrale fonctionnelle, l'objectif de cette étude était: d’examiner la réponse neurophysiologique des fumeurs chroniques à des images qui illustrent les effets négatifs de la cigarette (campagne anti-tabac); d’examiner le caractère affectif de cette réactivité utilisant des conditions contrôles (c.-à-d., images aversives non-liées au tabac et appétitives liées au tabac); d'examiner la connectivité fonctionnelle durant cette tâche entre les systèmes affectifs et exécutifs (une interaction qui peut favoriser ou entraver l'impact des évènements aversifs). Méthodes: 30 fumeurs chroniques ont passé une session de neuroimagerie durant laquelle ils devaient regarder des images appétitives et aversives de cigarettes, des images aversives non-reliées au tabac et des images neutres. Résultats: Les images aversives liés au tabagisme suscitent une plus grande activation dans le cortex médial préfrontal, l'amygdale, le gyrus frontal inférieur et le cortex orbitofrontal latéral en comparaison avec les images neutres, mais une moins grande activation dans des structures médiaux / sous-corticales comparé aux images aversives non-reliés et images appétitives reliées aux tabac. L’activité du système exécutif présente une connectivité fonctionnelle négative avec le système affectif lorsque les images aversives sont liées au tabac, mais pas quand elles ne le sont pas. Conclusions: Le modèle d'activation du cerveau observé suggère qu’il y a un biais dans la réactivité des fumeurs chroniques lorsqu’ils observent des représentations négatives de la consommation du tabac. L’activité du système exécutif cérébral semble promouvoir chez les fumeurs une baisse d’activité dans des régions impliquées dans la genèse d’une réponse physiologique affective; il s’agit d’un mécanisme qui permettrait de réduire l’impact persuasif de ces représentations des méfaits de la cigarette sur la consommation des fumeurs.
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Background. This study examined whether alcohol abuse patients are characterized either by enhanced schematic processing of alcohol related cues or by an attentional bias towards the processing of alcohol cues. Method. Abstinent alcohol abusers (N = 25) and non-clinical control participants (N = 24) performed a dual task paradigm in which they had to make an odd/even decision to a centrally presented number while performing a peripherally presented lexical decision task. Stimuli on the lexical decision task comprised alcohol words, neutral words and non-words. In addition, participants completed an incidental recall task for the words presented in the lexical decision task. Results. It was found that, in the presence of alcohol related words, the performance of patients on the odd/even decision task was poorer than in the presence of other stimului. In addition, patients displayed slower lexical decision times for alcohol related words. Both groups displayed better recall for alcohol words than for other stimuli. Conclusions. These results are interpreted as supporting neither model of drug cravings. Rather, it is proposed that, in the presence of alcohol stimuli, alcohol abuse patients display a breakdown in the ability to focus attention.
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Rationale: Liking, cravings and addiction for chocolate ("chocoholism") are often explained through the presence of pharmacologically active compounds. However, mere "presence" does not guarantee psycho-activity. Objectives: Two double-blind, placebo-controlled studies measured the effects on cognitive performance and mood of the amounts of cocoa powder and methylxanthines found in a 50 g bar of dark chocolate. Methods: In study 1, participants (n=20) completed a test battery once before and twice after treatment administration. Treatments included 11.6 g cocoa powder and a caffeine and theobromine combination (19 and 250 mg, respectively). Study 2 (n=22) comprised three post-treatment test batteries and investigated the effects of "milk" and "dark" chocolate levels of these methylxanthines. The test battery consisted of a long duration simple reaction time task, a rapid visual information processing task, and a mood questionnaire. Results: Identical improvements on the mood construct "energetic arousal" and cognitive function were found for cocoa powder and the caffeine+theobromine combination versus placebo. In chocolate, both "milk chocolate" and "dark chocolate" methylxanthine doses improved cognitive function compared with "white chocolate". The effects of white chocolate did not differ significantly from those of water. Conclusion: A normal portion of chocolate exhibits psychopharmacological activity. The identical profile of effects exerted by cocoa powder and its methylxanthine constituents shows this activity to be confined to the combination of caffeine and theobromine. Methylxanthines may contribute to the popularity of chocolate; however, other attributes are probably much more important in determining chocolate's special appeal and in explaining related self-reports of chocolate cravings and "chocoholism".
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Literatures have shown that Internet gaming disorder (IGD) subjects show impaired executive control and enhanced reward sensitivities than healthy controls. However, how these two networks jointly affect the valuation process and drive IGD subjects' online-game-seeking behaviors remains unknown. Thirty-five IGD and 36 healthy controls underwent a resting-states scan in the MRI scanner. Functional connectivity (FC) was examined within control and reward network seeds regions, respectively. Nucleus accumbens (NAcc) was selected as the node to find the interactions between these two networks. IGD subjects show decreased FC in the executive control network and increased FC in the reward network when comparing with the healthy controls. When examining the correlations between the NAcc and the executive control/reward networks, the link between the NAcc - executive control network is negatively related with the link between NAcc - reward network. The changes (decrease/increase) in IGD subjects' brain synchrony in control/reward networks suggest the inefficient/overly processing within neural circuitry underlying these processes. The inverse proportion between control network and reward network in IGD suggest that impairments in executive control lead to inefficient inhibition of enhanced cravings to excessive online game playing. This might shed light on the mechanistic understanding of IGD.
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Water deprivation-induced thirst is explained by the double-depletion hypothesis, which predicts that dehydration of the two major body fluid compartments, the extracellular and intracellular compartments, activates signals that combine centrally to induce water intake. However, sodium appetite is also elicited by water deprivation. In this brief review, we stress the importance of the water-depletion and partial extracellular fluid-repletion protocol which permits the distinction between sodium appetite and thirst. Consistent enhancement or a de novo production of sodium intake induced by deactivation of inhibitory nuclei (e.g., lateral parabrachial nucleus) or hormones (oxytocin, atrial natriuretic peptide), in water-deprived, extracellular-dehydrated or, contrary to tradition, intracellular-dehydrated rats, suggests that sodium appetite and thirst share more mechanisms than previously thought. Water deprivation has physiological and health effects in humans that might be related to the salt craving shown by our species.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Pós-graduação em Ciências da Motricidade - IBRC
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Drug addiction manifests clinically as compulsive drug seeking, and cravings that can persist and recur even after extended periods of abstinence. The fundamental principle that unites addictive drugs is that each one enhances synaptic DA by means that dissociate it from normal behavioral control, so that they act to reinforce their own acquisition. Our attention has focused on the study of phenomena associated with the consumption of alcohol and heroin. Alcohol has long been considered an unspecific pharmacological agent, recent molecular pharmacology studies have shown that acts on different primary targets. Through gene expression studies conducted recently it has been shown that the classical opioid receptors are differently involved in the consumption of ethanol and, furthermore, the system nociceptin / NOP, included in the family of endogenous opioid system, and both appear able to play a key role in the initiation of alcohol use in rodents. What emerges is that manipulation of the opioid system, nociceptin, may be useful in the treatment of addictions and there are several evidences that support the use of this strategy. The linkage between gene expression alterations and epigenetic modulation in PDYN and PNOC promoters following alcohol treatment confirm the possible chromatin remodeling mechanism already proposed for alcoholism. In the second part of present study, we also investigated alterations in signaling molecules directly associated with MAPK pathway in a unique collection of postmortem brains from heroin abusers. The interest was focused on understanding the effects that prolonged exposure of heroin can cause in an individual, over the entire MAPK cascade and consequently on the transcription factor ELK1, which is regulated by this pathway. We have shown that the activation of ERK1/2 resulting in Elk-1 phosphorylation in striatal neurons supporting the hypothesis that prolonged exposure to substance abuse causes a dysregulation of MAPK pathway.
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Pregnant African American women are at higher risk of having a preterm delivery and/or a low birthweight infant. Many factors are associated with adverse pregnancy outcomes but a food habit that deserves further study in the causal process is pica, a craving for, and ingestion of, nonnutritive substances such as laundry starch, clay, dirt, or ice. This food habit is more common in the African American population but has not been adequately studied in relation to preterm and/or low birth weight infants.^ Mothers (n = 281) with infants less than one year of age who participated in the Special Supplementary Food Program for Women, Infants, and Children (WIC) at clinics in Houston and Prairie View, Texas were interviewed regarding pica practices during pregnancy, dietary practices, and some demographic indices. Hospital records were abstracted for health information on the mothers and infants, including birthweight and gestational age at birth of the infant.^ The subjects were 88.6% African American, 6.8% Hispanic, and 4.6% Caucasian. Overall prevalence of pica was 76.5%. Pica prevalence by substance(s) was as follows: ice 53.7%; ice and freezer frost 14.6%; other substances such as baking soda, baking powder, cornstarch, laundry starch, and clay or dirt 8.2%; and 23.5% reported no pica. The women who reported ice/freezer frost pica had a higher percentage of illegal drug use and alcohol use during pregnancy. The women who reported other pica substances had the lowest mean educational level, highest gravidity, and a higher percentage smoked during pregnancy.^ There were no significant differences in nutrient intakes measured by the mean 24-hour dietary recalls between women who reported ice pica (n = 103) and women who denied pica (n = 50). The women who reported ice/freezer frost pica or other pica substances had more food cravings and food dislikes during pregnancy than those who reported ice pica or no pica.^ There were no differences in mean birthweight or mean gestational age at birth of infants born to mothers from the three pica groups and the no pica group but regression analyses revealed a possible relationship between pica, low maternal hemoglobin at delivery, and preterm birth. ^