Mood and cognitive performance effects of "energy" drink constituents: caffeine, glucose and carbonation

Energy drinks in Tamale: Understanding youth perceptions, consumption patterns, and related factors

Energy drinks (EDs) have become a popular choice for young people seeking physical and cognitive boosts, with ingredients such as caffeine, taurine, and B vitamins aimed at improving academic, athletic, and alertness levels. However, the popularity of these drinks is also driven by low prices, taste, brand loyalty, and gendered marketing, with boys being more likely to consume them. Despite the supposed benefits, EDs have been associated with high-risk behaviours, deaths, and adverse health effects, especially those related to cardiovascular risk. Meanwhile, in Ghana, the use of EDs is on the rise. Hence, this study aimed to examine the prevalence and consumption patterns, perceptions, and factors associated with ED consumption among the youth of the Tamale Metropolis. The study was cross-sectional, consisting of 541 participants. The group consisted of 340 males and 201 females, between the ages of 15 and 45. A questionnaire was utilized to obtain data on the respondents' consumption patterns and perceptions of EDs, as well as their socio-demographic characteristics. The results of the study indicated that a large percentage of the respondents, 98.7%, had consumed EDs before, while 78.7% currently consume them. Respondents believed that EDs provided additional energy (81.00%) and reduced stress (62.30%). However, they also perceived side effects such as insomnia (60.60%) and restlessness (51.40%). Also, the highest proportion of respondents (83.4%) had poor knowledge of EDs. They were unaware of the classification of EDs and their ingredients, side effects, and benefits. Age, marital status, level of education, work intensity, EDs served at gatherings, and knowledge of EDs was significantly associated with ED consumption (p < .05). Consumption was higher among those aged 26 to 35 years, singles, individuals with no formal education, and those with high work intensity. The high consumption was also associated with low knowledge levels. It is recommended that public health and nutrition professionals engage in further advocacy efforts to improve the youth's knowledge and perception of EDs in a positive manner. In addition, lawmakers should use legislation to influence consumption rates and safeguard the health of consumers.

Using caffeine as a chemical means to induce flow states

Flow is an intrinsically rewarding state characterised by positive affect and total task absorption. Because cognitive and physical performance are optimal in flow, chemical means to facilitate this state are appealing. Caffeine, a non-selective adenosine receptor antagonist, has been emphasized as a potential flow-inducer. Thus, we review the psychological and biological effects of caffeine that, conceptually, enhance flow. Caffeine may facilitate flow through various effects, including: i) upregulation of dopamine D1/D2 receptor affinity in reward-associated brain areas, leading to greater energetic arousal and 'wanting'; ii) protection of dopaminergic neurons; iii) increases in norepinephrine release and alertness, which offset sleep-deprivation and hypoarousal; iv) heightening of parasympathetic high frequency heart rate variability, resulting in improved cortical stress appraisal, v) modification of striatal endocannabinoid-CB1 receptor-signalling, leading to enhanced stress tolerance; and vi) changes in brain network activity in favour of executive function and flow. We also discuss the application of caffeine to treat attention deficit hyperactivity disorder and caveats. We hope to inspire studies assessing the use of caffeine to induce flow.

Novel Energy Drink Improves Cognitive Function and Mood, without Influencing Myocardial Oxygen Demand or Ventricular Repolarization in Adult Gamers: A Randomized, Double-Blind, Placebo-Controlled, Crossover Trial

OBJECTIVES

To examine the efficacy of acute consumption of a novel energy drink (C4S) versus placebo for improving cognitive and gaming performance and mood. Secondarily, we examined the cardiovascular safety profile of acute C4S consumption.

METHODS

Forty-five healthy, young adult video gamers completed two experimental visits in randomized order where they consumed either C4S or a placebo and then completed a validated battery of neurocognitive tests, played five video games, and completed a mood state survey. Blood pressure (BP), heart rate (HR), oxygen saturation, and electrocardiogram measurements were taken at baseline and repeated throughout each visit.

RESULTS

Acute consumption of C4S improved cognitive flexibility (absolute mean or median difference [95% CI] = +4.3 [2.2-6.4]; p < 0.001; d = 0.63), executive function (+4.3 [2.3-6.3]; p < 0.001; d = 0.63), sustained attention (+2.1 [0.6-3.6]; p = 0.01; d = 0.44), motor speed (+2.9 [0.8-4.9]; p < 0.001; d = 0.44), psychomotor speed (+3.9 [0.1-7.7]; p = 0.04; d = 0.32) working memory (+1.0 [0.1-1.9]; p = 0.02; d = 0.35), and performance in the two-dimensional visuospatial game Tetris (+463 [-419-2,065] pts; p = 0.049; d = 0.30) compared to placebo. C4S also improved Fatigue-Inertia (-1 [-3-0]; p = 0.004; d = 0.45), Vigor-Activity (+2.4 [1.3-3.6]; p < 0.001; d = 0.64), Friendliness (+0 [0-1]; p = 0.04; d = 0.32), and Total Mood Disturbance (-3 [-6-0]; p = 0.002; d = 0.44). BP increased slightly in C4S versus placebo, while HR decreased from baseline to post-drink in the C4S condition. Rate-pressure-product was higher in C4S versus placebo independent of time but did not increase from baseline. There was no effect on corrected QT interval.

CONCLUSION

Acute consumption of C4S was efficacious for cognitive performance, visuospatial gaming performance, and mood enhancement, and had no effect on myocardial oxygen demand or ventricular repolarization, despite being associated with increases in BP.

International society of sports nutrition position stand: energy drinks and energy shots

Position Statement: The International Society of Sports Nutrition (ISSN) bases the following position stand on a critical analysis of the literature regarding the effects of energy drink (ED) or energy shot (ES) consumption on acute exercise performance, metabolism, and cognition, along with synergistic exercise-related performance outcomes and training adaptations. The following 13 points constitute the consensus of the Society and have been approved by the Research Committee of the Society: Energy drinks (ED) commonly contain caffeine, taurine, ginseng, guarana, carnitine, choline, B vitamins (vitamins B1, B2, B3, B5, B6, B9, and B12), vitamin C, vitamin A (beta carotene), vitamin D, electrolytes (sodium, potassium, magnesium, and calcium), sugars (nutritive and non-nutritive sweeteners), tyrosine, and L-theanine, with prevalence for each ingredient ranging from 1.3 to 100%. Energy drinks can enhance acute aerobic exercise performance, largely influenced by the amount of caffeine (> 200 mg or >3 mg∙kg bodyweight [BW-1]) in the beverage. Although ED and ES contain several nutrients that are purported to affect mental and/or physical performance, the primary ergogenic nutrients in most ED and ES based on scientific evidence appear to be caffeine and/or the carbohydrate provision. The ergogenic value of caffeine on mental and physical performance has been well-established, but the potential additive benefits of other nutrients contained in ED and ES remains to be determined. Consuming ED and ES 10-60 minutes before exercise can improve mental focus, alertness, anaerobic performance, and/or endurance performance with doses >3 mg∙kg BW-1. Consuming ED and ES containing at least 3 mg∙kg BW-1 caffeine is most likely to benefit maximal lower-body power production. Consuming ED and ES can improve endurance, repeat sprint performance, and sport-specific tasks in the context of team sports. Many ED and ES contain numerous ingredients that either have not been studied or evaluated in combination with other nutrients contained in the ED or ES. For this reason, these products need to be studied to demonstrate efficacy of single- and multi-nutrient formulations for physical and cognitive performance as well as for safety. Limited evidence is available to suggest that consumption of low-calorie ED and ES during training and/or weight loss trials may provide ergogenic benefit and/or promote additional weight control, potentially through enhanced training capacity. However, ingestion of higher calorie ED may promote weight gain if the energy intake from consumption of ED is not carefully considered as part of the total daily energy intake. Individuals should consider the impact of regular coingestion of high glycemic index carbohydrates from ED and ES on metabolic health, blood glucose, and insulin levels. Adolescents (aged 12 through 18) should exercise caution and seek parental guidance when considering the consumption of ED and ES, particularly in excessive amounts (e.g. > 400 mg), as limited evidence is available regarding the safety of these products among this population. Additionally, ED and ES are not recommended for children (aged 2-12), those who are pregnant, trying to become pregnant, or breastfeeding and those who are sensitive to caffeine. Diabetics and individuals with preexisting cardiovascular, metabolic, hepatorenal, and/or neurologic disease who are taking medications that may be affected by high glycemic load foods, caffeine, and/or other stimulants should exercise caution and consult with their physician prior to consuming ED. The decision to consume ED or ES should be based upon the beverage's content of carbohydrate, caffeine, and other nutrients and a thorough understanding of the potential side effects. Indiscriminate use of ED or ES, especially if multiple servings per day are consumed or when consumed with other caffeinated beverages and/or foods, may lead to adverse effects. The purpose of this review is to provide an update to the position stand of the International Society of Sports Nutrition (ISSN) integrating current literature on ED and ES in exercise, sport, and medicine. The effects of consuming these beverages on acute exercise performance, metabolism, markers of clinical health, and cognition are addressed, as well as more chronic effects when evaluating ED/ES use with exercise-related training adaptions.

Knowledge, attitude, and perception of energy drinks consumption among university students in Jordan

Energy drinks gained popularity after the launch of Red Bull in 1997. Different brands are now available and young adults mainly consume these drinks. This study assesses the knowledge, attitude, and perception of energy drink consumption among university students in Jordan. A validated online survey was used to collect the required data, extracted from Google Forms into an Excel spreadsheet and statistically analysed using Statistical Package for Social Sciences version 24.0. A nationally representative sample of university students with a mean age of 22⋅2 ± 3⋅9 years (n 749) was obtained. The participating students demonstrated a neutral level of knowledge about energy drinks, as the mean score of knowledge = 7⋅1 ± 2⋅2 (out of 12), with 66 % (n 498) of them having consumed energy drinks and experienced their effects. Generally, the study's participants demonstrated a neutral attitude towards energy drinks and 70⋅5 % (n 528) acknowledged that energy drinks increase activity, but more than 70 % of them believed that energy drinks have harmful side effects. It was found that there is a significant (P-value <0⋅5) positive correlation between knowledge score and female gender, studying a medical major, and monthly income. The main reasons for consuming energy drinks were reported to be: to stay awake for longer, help study, and become more energetic. There is a need for more structured awareness campaigns to warn students about the possible side effects of these products in order to reduce the consumption and popularity of these drinks among students.

Bibliometric analysis of the effects of mental fatigue on athletic performance from 2001 to 2021

Aims

To explore the research hot topics and main contents in the field of the influence of mental fatigue on athletic performance, and to provide new ideas and directions for future research in this field.

Methods

Using CiteSpace and VOSviewer visualization tool software core collection of Web of Science database to TS = ("mental fatigue" OR "mental exertion" OR "cognitive fatigue" OR "Cognitive exertion" OR "mental exhaustion" OR "mental tiredness") AND ("athletic performance" OR "technical skill*" OR "Skill*" OR "technique" OR "decision making" OR "performance") AND ("Humans") searched for the influence of mental fatigue on athletic performance from 2001 to 2021 to conduct visual analysis. Research hot topics were analyzed from the aspects of high-impact countries/regions, institutions, authors, high-frequency keywords, and mutation terms.

Results

A total of 658 publications were identified finally, and there has been an increasing trend in the annual number of publications, with the United States ranking first in the number of publications and influence. Future research will focus on promoting the application of EEG technology as an objective indicator for assessing mental fatigue, exploring effective methods and measures for pharmacological or non-pharmacological interventions against fatigue, and focusing on the effects of mental fatigue on endurance performance, technical skills, and sports-related decision-making.

Conclusion

The results of the present study help us understand the status of the mental fatigue and athletic performance field and its recent developments.

Effects of Different Sources of Low-Dose Caffeine on Mood/Arousal and Cognitive Performance

In this study we investigated the effects of variously derived sources of low-dose caffeine on mood/arousal and cognitive performance. Twenty-two participants (15 men, 7 women; M age: 28.2, SD = 9.0 years) undertook five randomized, crossover trials in which they consumed either a water control (CON) or 80 mg of caffeine from one of four sources (coffee [COF], energy drink [END], capsule [CAP], and dissolvable mouth strip [STR]). We measured the participants' perceived efficacy of these varied caffeine sources pre-treatment; and we measured mood/arousal at pre-treatment, and again at 15 and 45 minutes post-treatment. We also measured choice reaction-time at 15 and 45 minutes post-treatment, and participants completed the psychomotor vigilance task (PVT) 45 minutes post-treatment. Caffeine increased participant ratings of alertness and decreased their ratings of tiredness irrespective of source (p's < .05), and all sources of caffeine decreased reaction time on the PVT (p's < .05), with ex-Gaussian distributional analysis localizing this to the tau-parameter, indicating lower variability. However, only the COF source was associated with improved 'overall mood' (p's < .05). Participants expected to perform better on the PVT with COF compared to CON, but there were no other significant associations between source expectancy and performance. In sum, a modest dose of caffeine, regardless of source, positively impacted mood/arousal and cognitive performance, and these effects did not appear to be influenced by expectations.

Ingestion of carbonated water increases middle cerebral artery blood velocity and improves mood states in resting humans exposed to ambient heat stress

Sugar-free carbonated water is consumed worldwide. The consumption of carbonated water is high in summer, when the heat loss responses of sweating and skin vasodilation are activated, and thermal perceptions (thermal sensation and comfort) and mood states are negatively modulated. However, whether ingesting carbonated water under ambient heat exposure modulates cerebral blood flow index, heat loss responses, thermal perceptions, and mood states remains to be determined. In this study, 17 healthy, habitually active, young adults (eight women) ingested 4 °C noncarbonated or carbonated water under 37 °C ambient heat-stressed resting conditions. Both drinks increased the middle cerebral artery mean blood velocity, an index of cerebral blood flow, and mean arterial pressure, with carbonated water exhibiting higher elevations than noncarbonated water (P < 0.05). However, the heart rate, sweat rate, and skin blood flow during and after drinking remained unchanged between the two conditions (P > 0.05). The thermal sensation and comfort after drinking remained unchanged between the two conditions (P > 0.05); but, a drink-induced reduction in sleepiness was higher, and drink-induced elevations in motivation and exhilaration were higher after ingesting carbonated water than those after ingesting noncarbonated water (P < 0.05). The analyses suggest that in humans under ambient heat-stressed resting conditions, ingestion of cold carbonated water increases the cerebral blood flow index, blood pressure, motivation, and exhilaration, whereas it decreases sleepiness relative to ingestion of noncarbonated cold water. However, ingestion of cold carbonated water fails to modulate thermoregulatory responses and thermal perception as opposed to noncarbonated cold water.

The Matrix Matters: Beverage Carbonation Impacts the Timing of Caffeine Effects on Sustained Attention

Both caffeine and the perception of refreshment delivered by cooling, tingling, and mouth-watering flavors have individually been shown to positively impact cognitive performance and mood, though presently there is limited evidence on their possible combined effects. This study explored the contribution of refreshing compounds in beverages, namely, carbon dioxide and citric acid, on the acute effects of caffeine on sustained attention and self-rated physical and mental energy. A randomized, controlled crossover trial was conducted by testing three products: a carbonated caffeinated beverage; a comparator caffeinated beverage; and a flavor-matched control beverage. Findings from 24 healthy adults revealed product-dependent variations in cognitive performance during a 60-min visual sustained-attention task, suggesting that the carbonated-caffeinated beverage led to faster, greater and more consistent levels of accuracy, compared to the control beverage. Specifically, significant differences were found between: (1) the carbonated-caffeinated beverage and the caffeinated beverage, and (2) between the caffeinated beverage and the control beverage for number of hits, reaction time and false alarm scores. Both caffeinated beverages led to higher physical and mental energy, and lower physical and mental fatigue 60-min post-consumption. These findings suggest beneficial effects on sustained attention through the combination of caffeine with refreshing compounds.

The Effects of Direct Red Bull Administration to Isolated Hearts of Trained and Untrained Rats Who Regularly Consumed or Did Not Consume Energy Drink: Focus on Cardiodynamics and Oxidative Stress

Energy drinks (EDs) contain caffeine and other active ingredients which affect cardiovascular system. The aims of this study were to examine direct effects of Red Bull (RB) on cardiodynamics and oxidative stress in isolated hearts of rats. The rats were divided into four groups: untrained rats who never consumed ED (dEDUT); untrained rats who consumed ED 5 days a week during 4 weeks (ch+dED-UT); rats trained 5 times a week for 4 weeks, but did not consume ED (dED-T); rats trained and consumed ED 5 times a week for 4 weeks (ch+dED-T). After sacrificing, hearts were isolated and perfused according to Langendorff technique. Through the isolated heart of all rats in each group, RB was administered. The parameters of cardiac function were recorded, and the levels of prooxidants were measured in the coronary effluent during coronary autoregulation. Rats in ch+dED-UT group had significantly lower rates of myocardial contraction and relaxation compared to rats in dED-UT group. The same effect was recorded in the dED-T group compared to dED-UT group. The levels of hydrogen peroxide were significantly higher in trained rats. Rats in ch+dED-T group also had significantly higher levels of superoxide anion radical and index of lipid peroxidation, as well as lower levels of nitrites when compared to ch+dED-UT group, while opposite effect was recorded in rats in dED-T group compared to dEDUT group. The RB could have a potentially negative inotropic effect in chronic consumers. Prooxidative effect of RB was most pronounced in trained chronic consumers.

Self-Reported Emotions and Facial Expressions on Consumer Acceptability: A Study Using Energy Drinks

Emotional responses elicited by foods are of great interest for new product developers and marketing professionals, as consumer acceptance proved to be linked to the emotions generated by the product in the consumers. An emotional measurement is generally considered an appropriate tool to differentiate between the products of similar nutritional value, flavour, liking and packaging. Novel methods used to measure emotions include self-reporting verbal and visual measurements, and facial expression techniques. This study aimed to evaluate the explicit and implicit emotional response elicited during the tasting of two different brands (A and B) of energy drinks. The explicit response of consumers was assessed using liking (nine-point hedonic scale), and emotions (EsSense Profile^®—Check-All-That-Apply questionnaire), and implicit emotional responses were evaluated by studying facial expressions using the Affectiva Affdex^® software. The familiarity of the product and purchase intent were also assessed during the study. The hedonic rating shows a significant difference in liking between the two brands of energy drink during the tasting session. For the explicit emotional responses, participants elicited more positive emotions than the negative emotions for both energy drinks. However, participants expressed “happy”, “active” and “eager” emotions more frequently for energy drink A. On the other hand, the implicit emotional responses through facial expressions indicated a high level of involvement of the participants with energy drink B as compared to energy drink A. The study showed that overall liking and the explicit and implicit emotional measurements are weakly to moderately correlated.

International society of sports nutrition position stand: caffeine and exercise performance

Following critical evaluation of the available literature to date, The International Society of Sports Nutrition (ISSN) position regarding caffeine intake is as follows: 1. Supplementation with caffeine has been shown to acutely enhance various aspects of exercise performance in many but not all studies. Small to moderate benefits of caffeine use include, but are not limited to: muscular endurance, movement velocity and muscular strength, sprinting, jumping, and throwing performance, as well as a wide range of aerobic and anaerobic sport-specific actions. 2. Aerobic endurance appears to be the form of exercise with the most consistent moderate-to-large benefits from caffeine use, although the magnitude of its effects differs between individuals. 3. Caffeine has consistently been shown to improve exercise performance when consumed in doses of 3-6 mg/kg body mass. Minimal effective doses of caffeine currently remain unclear but they may be as low as 2 mg/kg body mass. Very high doses of caffeine (e.g. 9 mg/kg) are associated with a high incidence of side-effects and do not seem to be required to elicit an ergogenic effect. 4. The most commonly used timing of caffeine supplementation is 60 min pre-exercise. Optimal timing of caffeine ingestion likely depends on the source of caffeine. For example, as compared to caffeine capsules, caffeine chewing gums may require a shorter waiting time from consumption to the start of the exercise session. 5. Caffeine appears to improve physical performance in both trained and untrained individuals. 6. Inter-individual differences in sport and exercise performance as well as adverse effects on sleep or feelings of anxiety following caffeine ingestion may be attributed to genetic variation associated with caffeine metabolism, and physical and psychological response. Other factors such as habitual caffeine intake also may play a role in between-individual response variation. 7. Caffeine has been shown to be ergogenic for cognitive function, including attention and vigilance, in most individuals. 8. Caffeine may improve cognitive and physical performance in some individuals under conditions of sleep deprivation. 9. The use of caffeine in conjunction with endurance exercise in the heat and at altitude is well supported when dosages range from 3 to 6 mg/kg and 4-6 mg/kg, respectively. 10. Alternative sources of caffeine such as caffeinated chewing gum, mouth rinses, energy gels and chews have been shown to improve performance, primarily in aerobic exercise. 11. Energy drinks and pre-workout supplements containing caffeine have been demonstrated to enhance both anaerobic and aerobic performance.

Internalizing symptoms modulate real-world affective response to sweet food and drinks in children

The purpose of the current study was to examine affective response to sweet foods and drinks as a function of children's internalizing symptoms using ecological momentary assessment (EMA). A sample of 192 8-12-year-old children completed a self-report measure of internalizing symptoms and EMA prompts of affect and food intake for eight days, excluding time at school. There was an interaction between sweet food intake and internalizing symptoms for positive affect and for sweet drink intake and internalizing symptoms for negative affect. Those low in internalizing symptoms had significantly lower positive affect after consumption of sweet foods compared to when they did not consume sweet foods whereas those higher in internalizing symptoms had slightly, but not significantly, higher positive affect after consumption of sweet foods. Those low in internalizing symptoms had significantly higher negtive affect after consumption of sweet drinks compared to when they did not consume sweet drinks whereas those higher in internalizing symptoms had slightly, but not significantly, lower negative affect after consumption of sweet drinks. Findings highlight the ways in which internalizing symptoms may modulate affective response to sweet foods and drinks.

Energy drinks consumption and perceptions among University Students in Beirut, Lebanon: A mixed methods approach

Background

Energy drinks (ED) are caffeine- and sugar-rich beverages with other ingredients that are marketed for their energy-boosting and performance-enhancing effects. The consumption of these drinks, with and without alcohol, is dramatically increasing worldwide, despite the reported side effects and potential harms to consumers. Few studies, to date, have explored the perceptions and experiences of young adults towards these beverages.

Objective

The present study aimed to explore the consumption patterns and correlates of ED consumption, as well as the perceptions and experiences of university students in Lebanon towards these beverages.

Methods

A sequential explanatory mixed-methods approach was adopted. Data collection was conducted in two private universities in Beirut, Lebanon. A self-administered 36-item quantitative survey was first used to explore the prevalence and correlates of ED consumption among a convenience sample of university students (n = 226). The survey included questions related to socio-demographic characteristics, anthropometric measurements, and other lifestyle behaviors, including physical activity of university students. The subsequent qualitative phase consisted of focus group discussions (FGD) conducted to further examine the perceptions and experiences of university students towards ED. Descriptive statistics and logistic regression analyses were conducted using survey data, whereas the transcribed FGD were analyzed thematically.

Results

A total of 226 university students completed the survey. Results showed that 45% of survey respondents consumed ED at least once in their life (ever consumers), among which 30% reported consumption of ED mixed with alcohol (AmED). Adjusting for socio-demographic and anthropometric characteristics, coffee and sports drinks consumption were significantly associated with ED (OR = 2.45, 95% CI = 1.20, 5.00, and OR = 4.88, 95%CI = 2.41, 9.88, respectively). In addition, physically active participants were 1.89 times (95%CI = 1.01, 3.51) more likely to consume ED compared to their inactive counterparts. During the qualitative phase, a total of six FGD were conducted with 29 university students, who reported consuming ED at least once per month. Three main themes were derived reflecting individual-, interpersonal/social- and environmental-level factors affecting ED consumption among university students. These themes were further supported by eight subthemes, including: perceived benefits of ED, experienced side effects, misinformation about content of ED, peer pressure and social image, as well as affordability and accessibility of ED.

Conclusion

Findings highlight the need for public health policies and programs to curb the growing public health phenomenon of ED consumption amongst university students. Such programs should consider the multi-level factors affecting ED consumption at the individual, interpersonal/social, and environmental levels, including educational campaigns on ED potential harms, regulating ED content and labeling, as well as restricting sales and marketing of these beverages, especially among young consumers.

Prevalence and Predictors of Depression, Anxiety and Stress Symptoms in Paramedics at Saudi Red Crescent Authority

Background:

Emergency medical professionals often encounter situations when dealing with patients that can affect their mental health. In Saudi Arabia, there is paucity of data regarding the mental health of paramedics involved in prehospital care.

Objectives:

To determine the prevalence and predictors of stress, anxiety and depression symptoms among paramedics working at Saudi Red Crescent Authority (SRCA) stations in Riyadh, Saudi Arabia.

Methods:

This cross-sectional, questionnaire study included all paramedics working in the prehospital medical services of 21 SRCA stations in Riyadh (N = 300) between March and June 2017. Sociodemographic data were collected using a self-reporting questionnaire, and the Arabic version of the Depression Anxiety and Stress Scale-21 was used to identify the states of stress, anxiety and depression. Bivariate analysis using chi-square test and multivariate logistic regression analysis were performed to determine the association between sociodemographic factors and mental health.

Results:

In total, 240 emergency medical professionals responded (response rate = 80%). Of these, 30.5% had stress, 40% had anxiety and 26.7% had depression. All cases of stress were of mild-to-moderate level, while 5.1% of the respondents had severe-to-extremely severe anxiety and 1.3% had severe depression; there were no cases of extremely severe depression. Number of mission calls was identified as a predictor for stress and anxiety; intake of medications for noncommunicable diseases as a predictor for stress and depression; hours of sleep/day for anxiety and depression and use of stimulant beverages other than tea, coffee and energy drinks as predictors for anxiety.

Conclusion:

This study demonstrates that stress, anxiety and depressive symptoms are relatively common in paramedics working at SRCA stations in Riyadh. The authors suggest that the above-mentioned predictors should be monitored in paramedics and interventions should be made when necessary.

Impact of Energy Drinks on Health and Well-being

PURPOSE OF REVIEW

Energy drinks and energy shots are functional supplements with higher caffeine content marketed toward adolescents and young adults with the intention of boosting energy. Parallel to its rising popularity, there are safety concerns with the consumption of these beverages. Herein, we reviewed the impact these supplements produce on health and well-being.

RECENT FINDINGS

Most of the promoted benefits of the beverages can be attributed to caffeine. The physiologic effects, if any, of other ingredients such as vitamins and herbal extracts are unclear. The presence of a higher caffeine content as compared to soft drinks may predispose to caffeine intoxication in susceptible individuals. Also, the practice of co-ingestion of these beverages with alcohol is still prevalent and associated with serious consequences. Strict regulations (restriction of sales, clear warning labels, capping caffeine levels) and public education may help prevent the adverse outcomes from these beverages.

The Consumption of Breakfast, Fish and/or Caffeine does not Predict Study Progress in Adult Distance Education

Consumption of breakfast, fish, or caffeine are each separately often investigated in relation to learning performance in traditional education, but not in distance education (DE). The objective of this study was to investigate whether the relations between the consumption of breakfast, fish, and/or caffeine on the one hand and learning performance on the other are also found in DE students. This population is different from traditional students and characterized by a different profile in terms of age, personal and work responsibilities as well as other demographics. In an observational longitudinal study, the consumption of breakfast, fish, and caffeine of 1157 DE students (18-76 years old, mean 35.8 ± 11.1 years) was used to predict learning performance using multiple regression analysis. In an online digital survey, university students provided information about their consumption of these nutritional measures and on important covariates. Learning performance, measured as study progress (i.e., the number of successfully completed modules), was evaluated objectively after 14 months. Results showed that adding the consumption of breakfast, fish, and caffeine to the covariate model did not fit the data better, χ² (3, N = 1155) = 3.287, p = 0.35. This means that neither the consumption of breakfast nor fish nor caffeine predicted study progress in adults participating in DE. This study is important as it is the first to report on these relations in this specific age group and educational setting, which is increasingly important due to the increased preference for this type of education.

Sugar rush or sugar crash? A meta-analysis of carbohydrate effects on mood

The effect of carbohydrate (CHO) consumption on mood is much debated, with researchers reporting both mood improvements and decrements following CHO ingestion. As global consumption of sugar-sweetened products has sharply increased in recent years, examining the validity of claims of an association between CHOs and mood is of high importance. We conducted a systematic review and meta-analysis to evaluate the relationship between acute CHO ingestion and mood. We examined the time-course of CHO-mood interactions and considered the role of moderator variables potentially affecting the CHO-mood relationship. Analysis of 176 effect sizes (31 studies, 1259 participants) revealed no positive effect of CHOs on any aspect of mood at any time-point following their consumption. However, CHO administration was associated with higher levels of fatigue and less alertness compared with placebo within the first hour post-ingestion. These findings challenge the idea that CHOs can improve mood, and might be used to increase the public's awareness that the 'sugar rush' is a myth, inform health policies to decrease sugar consumption, and promote healthier alternatives.

The Effects of Carbohydrates, in Isolation and Combined with Caffeine, on Cognitive Performance and Mood-Current Evidence and Future Directions

This review examines the effects of carbohydrates, delivered individually and in combination with caffeine, on a range of cognitive domains and subjective mood. There is evidence for beneficial effects of glucose at a dose of 25 g on episodic memory, but exploration of dose effects has not been systematic and the effects on other cognitive domains is not known. Factors contributing to the differential sensitivity to glucose facilitation include age, task difficulty/demand, task domain, and glucoregulatory control. There is modest evidence to suggest modulating glycemic response may impact cognitive function. The evidence presented in this review identifies dose ranges of glucose and caffeine which improve cognition, but fails to find convincing consistent synergistic effects of combining caffeine and glucose. Whilst combining glucose and caffeine has been shown to facilitate cognitive performance and mood compared to placebo or glucose alone, the relative contribution of caffeine and glucose to the observed effects is difficult to ascertain, due to the paucity of studies that have appropriately compared the effects of these ingredients combined and in isolation. This review identifies a number of methodological challenges which need to be considered in the design of future hypothesis driven research in this area.

Use pattern and predictors of use of highly caffeinated energy drinks among South Korean adolescents: a study using the Health Belief Model

OBJECTIVES

Concerns about the use of highly caffeinated energy drinks among Korean adolescents remains. We compared adolescents' perceptions regarding the use of drinks to their behaviours and factors.

DESIGN

A structured questionnaire based on the Health Belief Model was administered to 850 freshmen and sophomores at three high schools in Bucheon, South Korea. Benefits were defined as beneficial effects from the use of highly caffeinated energy drinks (eg, awakening from sleepiness) and harms as adverse effects of the drinks (eg, cardiac palpitation). Likelihood of action represents the likelihood of taking actions that are perceived to be more beneficial after comparison of the benefits and harms of caffeine use. Descriptive analysis was used to quantify the relationship between their beliefs about highly caffeinated energy drinks and their use. We conducted hierarchical logistic regression to compute ORs and 95% CIs for: (1) demographic factors, (2) health threat, (3) likelihood of action and (4) cues to act.

RESULTS

Altogether, 833 students responded to the questionnaire (effective response rate=98.0%). About 63.0% reported use of highly caffeinated energy drinks and 35.2% had used them as needed and habitually. The more susceptible the respondents perceived themselves to be to the risk of using these drinks, the less likely they were to use them (OR: 0.73, 95% CI 0.50 to 1.06). The more severe the perception of a health threat, the less that perception was associated with use (OR: 0.44, 95% CI 0.29 to 0.67). Likelihood of action was the strongest predictor of use, explaining 12.5% in use. Benefits and harms (OR: 4.43, 95% CI 2.77 to 7.09; OR: 1.86, 95% CI 1.16 to 2.99) also were significant predictors.

CONCLUSIONS

Enhancing adolescents' perceptions of benefits and harms regarding using highly caffeinated energy drinks could be an effective way to influence the use of these drinks.

Acute impact of caffeinated alcoholic beverages on cognition: A systematic review

INTRODUCTION

Energy drinks are popular beverages that are supposed to counteract sleepiness, increase energy, maintain alertness and reduce symptoms of hangover. Cognitive enhancing seems to be related to many compounds such as caffeine, taurine and vitamins. Currently, users mostly combine psychostimulant effects of energy drinks to counteract sedative effects of alcohol. However, recent literature suggests that this combination conducts to feel less intoxicated but still impaired. The goal of the present article is to review cognitive impact and subjective awareness in case of caffeinated alcoholic beverage (CAB) intoxication.

METHOD

PubMed (January 1960 to March 2016) database was searched using the following terms: cognitive impairments, alcohol, energy drinks; cognition, alcohol, caffeine.

RESULTS

99 papers were found but only 12 randomized controlled studies which explored cognitive disorders and subjective awareness associated with acute CAB or AED (alcohol associated with energy drinks) intoxication were included.

DISCUSSION

The present literature review confirmed that energy drinks might counteract some cognitive deficits and adverse effects of alcohol i.e. dry mouth, fatigue, headache, weakness, and perception of intoxication due to alcohol alone. This effect depends on alcohol limb but disappears when the complexity of the task increases, when driving for example. Moreover, studies clearly showed that CAB/AEDs increase impulsivity which conducts to an overconsumption of alcohol and enhanced motivation to drink compared to alcohol alone, potentiating the risk of developing addictive behaviors. This is a huge problem in adolescents with high impulsivity and immature decision making processes.

CONCLUSION

Although energy drinks counteract some cognitive deficits due to alcohol alone, their association promotes the risk of developing alcohol addiction. As a consequence, it is necessary to better understand the neurobiological mechanisms underlying these interactions in order to better prevent the development of alcohol dependence.

Association between energy drink intake, sleep, stress, and suicidality in Korean adolescents: energy drink use in isolation or in combination with junk food consumption

BACKGROUND

A considerable amount of research suggests that the frequent use of caffeinated energy drinks may be associated with undesirable effects, particularly so in children and adolescents. This study aimed to investigate the associations between energy drink intake and mental health problems, in isolation or in combination with junk food consumption, in a nationally representative sample of Korean adolescents.

METHODS

Data from the 2015 Korean Youth Risk Behavior Web-Based Survey, collected from 68,043 adolescents aged 12-18 years (mean age 15.09 ± 1.72 years), were analyzed. Questionnaires were administered to collect information related to dietary behavior including energy drink intake and junk food consumption. Single item measures of sleep dissatisfaction, stress, depression, suicidal ideation, suicide plan, and suicide attempt were also administered. Associations between energy drink intake and sleep dissatisfaction, perceived severe stress, persistent depressive mood, and suicidality were investigated, and a multivariate approach was taken so that additional variance from demographic and lifestyle factors could be controlled for statistically.

RESULTS

Energy drink intake was significantly associated with sleep dissatisfaction (adjusted odd ratios [AORs] = 1.64 and 1.25), severe stress (AORs = 2.23 and 1.38), depressive mood (AOR = 2.59 and 1.51), suicidal ideation (AORs = 3.14 and 1.43), suicide plan (AORs = 4.65 and 1.78), and suicide attempt (AORs = 6.79 and 1.91), with a higher risk for more frequent use of energy drinks (≥5 times/wk) than for less frequent use (1-4 times/wk). The detrimental effect of energy drinks on mental health was particularly prominent in frequent junk food consumers.

CONCLUSIONS

Our data suggest that energy drink intake had detrimental effects related to stress, sleep dissatisfaction, mood, and suicidality, in isolation or in combination with junk food consumption, in Korean adolescents. However, the cross-sectional study design prevents our ability to assess causal relationships.

Energy drinks consumption in Italian adolescents: preliminary data of social, psychological and behavioral features

BACKGROUND

The aim of this study was to investigate the prevalence of energy drink (ED) consumption and the associations with social, psychological and behavioral features among an Italian adolescent sample.

METHODS

A cross-sectional prevalence study of 450 Italian adolescents attending middle school was conducted. The Italian versions of the European Food Safety Authority's adolescent Energy Drinks Questionnaire and of the Depression and Anxiety in Youth Scale (DAYS) were administered to evaluate ED use and its psychological correlates. Odds ratios (OR) with 95% confidence intervals (CI) were calculated using a logistic model to estimate the associations between ED consumption and socio-demographic characteristics, psychological factors and risky behaviors.

RESULTS

The prevalence of ED consumers was 57%, of whom 49% used alcohol mixed with ED. A total of 9% exhibited high chronic consumption, 31% average chronic consumption and 8% high acute consumption. Males were significantly more likely to use ED (OR=2.7, 95% CI: 1.8-4.0, P=0.00) and to engage in high acute consumption (OR=4.0, 95% CI: 1.1-13.8, P=0.03). Regular smoking was associated with ED use (OR=3.4, 95% CI: 1.2-9.1, P=0.02). No relationship was observed between ED use and depression (OR=1.6, 95% CI: 0.9-3.0, P=0.10) and anxiety (OR=0.8, 95% CI: 0.5-1.4, P=0.44), although those who were depressed with a suggestive but not statistically significant increased risk of acute ED use (OR=2.7, 95% CI: 1.0-7.4, P=0.06).

CONCLUSIONS

The prevalence of ED consumption among middle school Italian students was high and it was associated with another risky behavior, smoking, but not with anxiety or depression. About half of ED consumers used alcohol mixed with ED.

A Review of Energy Drinks and Mental Health, with a Focus on Stress, Anxiety, and Depression

Background: Concerns have been expressed regarding the potential for caffeinated energy drinks to negatively affect mental health, and particularly so in young consumers at whom they are often targeted. The products are frequently marketed with declarations of increasing mental and physical energy, providing a short-term boost to mood and performance. Although a certain amount of evidence has accumulated to substantiate some of these claims, the chronic effects of energy drinks on mental health also need to be addressed.

Methods: To review the relevant literature, PubMed and PsycINFO were searched for all peer-reviewed articles published in English that addressed associations between energy drink use and mental health outcomes. Case reports were also considered, though empirical studies investigating acute mood effects were excluded as a review of such articles had recently been published. Fifty-six articles were retrieved: 20 of these (along with eight more identified through other means) were included in the current review, and, because the majority addressed aspects of stress, anxiety, and depression, particular focus was placed on these outcomes.

Results: Though a number of null findings (and one negative relationship) were observed, the majority of studies examined reported positive associations between energy drink consumption and symptoms of mental health problems.

Conclusions: Though the findings imply that energy drink use may increase the risk of undesirable mental health outcomes, the majority of research examined utilized cross-sectional designs. In most cases, it was therefore not possible to determine causation or direction of effect. For this reason, longitudinal and intervention studies are required to increase our understanding of the nature of the relationships observed.

Effects of energy and sports drinks on tooth structures and restorative materials

Sports and energy drinks are consumed by more people than ever. Sports and energy drinks may enhance physical resistance, stimulate metabolism, prevent rehydration and replace electrolytes during high activity efforts. However, these drinks often have a low pH and are acidic, which can erode enamel and dentin, and increase dentine hypersensitivity. In addition to the adverse effects of sports and energy drinks on tooth structures, they often have the potential to damage restorative materials. These drinks often contain artificial colors which have potential to discolor resin composite materials and glass ionomers. The acidic nature of these drinks could also lead to a degradation, increase in wear, and roughening of the surface of the restorative materials. Many of the negative consequences of sport and energy drinks can be related to their over-consumption among children and teenagers. Patients should be advised to have a healthy diet, and consume soft and energy drinks in moderation, to avoid any negative dental or health consequences. The over-consumption of sports and energy drinks which are high in sugar and have the lowest pH are most likely to cause avoidable dental problems.

Knowledge, Attitudes, and Practices on Energy Drink Consumption and Side Effects in a Cohort of Medical Students

The purpose of this study was to evaluate knowledge, attitudes, and practices concerning energy drink consumption and the prevalence of side effects among medical students. Twenty-two percent of respondents were regular users, particularly men (p < .0005). Users were younger (p = .027) and drank alcohol more frequently (p = .008) than "non-users." Forty-nine percent consumed alcohol associated with energy drinks. Forty-five percent of medical students declared side effects after energy drink consumption, such as palpitations (35%), insomnia (21%), and irritability (20%). The study confirms a large use of energy drinks among students and the occurrence of side effects. The use of energy drinks may influence the ingestion of large amounts of alcohol.

EFFECT OF ENERGY DRINKS ON SELECTED FINE MOTOR TASKS

This study assessed the effect of energy shots on selected fine motor tasks. The participants were college-age male (n=19; M age=20.5 yr., SD=0.7) and female (n=21; M age=21.1 yr., SD=0.7) volunteers who were assessed on hand steadiness, choice reaction time, rotary pursuit, and simple reaction time. The energy shots group scored significantly poorer on the hand steadiness tests and significantly better on choice reaction time and simple reaction time tests. The enhanced reaction time and disruption in hand steadiness afforded by energy shots would not be apparent in many gross motor activities, but it is possible that reaction time improvement could be beneficial in sports that require quick, reflexive movements. However, the potential adverse psychological and physiological effects warrant discretionary use of such products.

Influence of energy drink ingredients on mood and cognitive performance

Sales of energy products have grown enormously in recent years. Manufacturers claim that the products, in the form of drinks, shots, supplements, and gels, enhance physical and cognitive performance, while users believe the products promote concentration, alertness, and fun. Most of these products contain caffeine, a mild psychostimulant, as their foremost active ingredient. However, they also contain additional ingredients, e.g., carbohydrates, amino acids, herbal extracts, vitamins, and minerals, often in unspecified amounts and labeled as an "energy blend." It is not clear whether these additional ingredients provide any physical or cognitive enhancement beyond that provided by caffeine alone. This article reviews the available empirical data on the interactive effects of these ingredients and caffeine on sleep and cognitive performance and suggests objectives for future study.

Effect of energy drink and caffeinated beverage consumption on sleep, mood, and performance in children and adolescents

The increasing availability of highly caffeinated beverages, including energy drinks, in the United States has resulted in a rise in consumption by children and adolescents. In addition, there is mounting evidence that these products are often consumed by youth for their perceived fatigue-mitigating and mood- or performance-enhancing effects. Although such perceptions by children and adolescents about the potential consequences of caffeine consumption are highly likely to influence decision making regarding the use of such products, there is still a relative paucity of studies that focus on the effect of caffeinated beverages on sleep, mood, and performance in the pediatric population. This review summarizes the following aspects of this topic, as derived from the information currently available: 1) the perception, among youth, of caffeine's risks and benefits and the sources of information about caffeine, particularly with regard to sleep, mood, and performance; 2) the bidirectional effect of caffeine on sleep in children and adolescents and the association of caffeine with other sleep-related practices, and 3) the evidence that supports caffeine as a performance and mood enhancer as well as a countermeasure to sleepiness in the pediatric population. Finally, gaps in knowledge are identified, and a direction for future research is outlined.

Cumulative neurobehavioral and physiological effects of chronic caffeine intake: individual differences and implications for the use of caffeinated energy products

The use of caffeine-containing energy products has increased worldwide in recent years. All of the top-selling energy drinks contain caffeine, which is likely to be the primary psychoactive ingredient in these products. Research shows that caffeine-containing energy products can improve cognitive and physical performance. Presumably, individuals consume caffeine-containing energy products to counteract feelings of low energy in situations causing tiredness, fatigue, and/or reduced alertness. This review discusses the scientific evidence for sleep loss, circadian phase, sleep inertia, and the time-on-task effect as causes of low energy and summarizes research assessing the efficacy of caffeine to counteract decreased alertness and increased fatigue in such situations. The results of a placebo-controlled experiment in healthy adults who had 3 nights of total sleep deprivation (with or without 2-hour naps every 12 hours) are presented to illustrate the physiological and neurobehavioral effects of sustained low-dose caffeine. Individual differences, including genetic factors, in the response to caffeine and to sleep loss are discussed. The review concludes with future directions for research on this important and evolving topic.

Evidence and knowledge gaps for the association between energy drink use and high-risk behaviors among adolescents and young adults

Sales of energy drinks have increased rapidly since their introduction to the marketplace in the 1990s. Despite the health concerns raised about these beverages, which are often highly caffeinated, surprisingly little data are available to estimate the prevalence of their use. This review presents the results of secondary data analyses of a nationally representative data set of schoolchildren in the United States and reviews the available research on the association between energy drink use and risk-taking behaviors. Approximately one-third of the students surveyed were recent users of energy drinks, with substantial variation by age, sex, and race/ethnicity. Among the health and safety concerns related to energy drinks and their consumption is the possible potentiation of risk-taking behaviors. The review of available research reveals that, although there does appear to be a strong and consistent positive association between the use of energy drinks and risk-taking behavior, all but one of the available studies used cross-sectional designs, thereby limiting the ability to make inferences about the temporal nature of the association. Thus, more research is needed to understand the nature of this association and how energy drinks, particularly those containing caffeine, might impact adolescent health and safety, especially given the high prevalence of their use among youth.

Effects of two doses of glucose and a caffeine-glucose combination on cognitive performance and mood during multi-tasking

BACKGROUND

This study assessed the effects of two doses of glucose and a caffeine-glucose combination on mood and performance of an ecologically valid, computerised multi-tasking platform.

MATERIALS AND METHODS

Following a double-blind, placebo-controlled, randomised, parallel-groups design, 150 healthy adults (mean age 34.78 years) consumed drinks containing placebo, 25 g glucose, 60 g glucose or 60 g glucose with 40 mg caffeine. They completed a multi-tasking framework at baseline and then 30 min following drink consumption with mood assessments immediately before and after the multi-tasking framework. Blood glucose and salivary caffeine were co-monitored.

RESULTS

The caffeine-glucose group had significantly better total multi-tasking scores than the placebo or 60 g glucose groups and were significantly faster at mental arithmetic tasks than either glucose drink group. There were no significant treatment effects on mood. Caffeine and glucose levels confirmed compliance with overnight abstinence/fasting, respectively, and followed the predicted post-drink patterns.

CONCLUSION

These data suggest that co-administration of glucose and caffeine allows greater allocation of attentional resources than placebo or glucose alone. At present, we cannot rule out the possibility that the effects are due to caffeine alone Future studies should aim at disentangling caffeine and glucose effects.

The potential adverse effect of energy drinks on executive functions in early adolescence

Introduction: Manufacturers of energy drinks (EDs) claim their products improve cognitive performance. Young adolescents are in a critical developmental phase. The impact of ED intake on their development is not yet clear. Therefore, we studied the associations of both caffeine intake and ED consumption with executive functions (EFs), and the role of pubertal status and sleeping problems.

Methods: A sample of 509 participants (mean age: 13.1 years, SD 0.85; age range: 11–16 years) participated in the study. The level of pubertal development was classified in five pubertal status categories. Participants were asked to report their caffeine (for example coffee) and ED consumption for each day of the week. In addition, they indicated sleep quality by reporting problems falling asleep or waking up and/or interrupted sleep. EFs were assessed by self- and parent reports of the Behavior Rating Inventory of Executive Function (BRIEF).

Results: Consuming on average one or more ED(s) a day was associated with more problems in self-reported behavior regulation and metacognition, and with more problems in parent-reported metacognition. Only high caffeine consumption (two or more cups a day) was associated with parent-reported problems with metacognition. The sum of caffeine and ED use was associated with a higher amount of problems with self-reported metacognition and parent reported behavior regulation. The effect estimates for the association between caffeine and ED use combined and EFs did not exceed those of EDs or caffeine separately. Adjusting for pubertal status, gender, educational level, number of sleeping problems and hours of sleep did not change the effect estimates substantially.

Conclusion: The observed associations between ED consumption and EFs suggest that regular consumption of EDs—even in moderate amounts—may have a negative impact on daily life behaviors related to EF in young adolescents.

An emerging adolescent health risk: caffeinated energy drink consumption patterns among high school students

OBJECTIVE

To examine the prevalence, patterns, and correlates of energy drink use among adolescents, and determine whether more frequent use of energy drinks is associated with poorer health and behavioral outcomes.

METHODS

Data were from a 2012 cross-sectional survey of 8210 students in grades 7, 9, 10 and 12 attending public schools in Atlantic Canada. Multinomial logistic regression analysis was used to examine correlates of energy drink use patterns, including substance use, sensation seeking, risk of depression, and socioeconomic status.

RESULTS

Nearly two-thirds of survey respondents (62%) reported consuming energy drinks at least once in the previous year, with about 20% reporting use once or more per month. Sensation seeking, depression, and substance use were all higher among energy drink users relative to non-users, and in higher frequency users relative to lower frequency users.

CONCLUSIONS

The prevalence of energy drink consumption among high school students was high. The association of energy drinks with other potential negative health and behavioral outcomes suggests that use of these products may represent a marker for other activities that may negatively affect adolescent development, health and well-being.

Energy drink consumption and associations with demographic characteristics, drug use and injury among adolescents

OBJECTIVE

To examine energy drink consumption and its association with demographic characteristics, drug use, and injury among adolescents.

METHODS

Data on 4,342 adolescents were derived from the 2011 Ontario Student Drug Use and Health Survey, a province-wide school-based survey of students in grades 7 through 12. The survey was based on a two-stage cluster design and analyses include appropriate adjustments for the complex sample design.

RESULTS

Overall, 49.6% of adolescents had consumed energy drinks in the previous year. A total of 13.8% of seventh grade students had consumed energy drinks in the previous week compared to 19.1% of adolescents overall. Energy drink consumption in the previous year was highly associated with having used tobacco and cannabis in the previous year, the non-medicinal use of prescription drugs in the previous year, and binge drinking in the previous month. Consumption was also highly associated with sensation-seeking and self-reports of medical treatment for an injury (reported by 16% and 42% of adolescents, respectively). The odds of consuming energy drinks did not vary significantly for males and females, and sex was not a significant moderator of the associations examined.

CONCLUSION

These findings support the need for greater awareness of the extent of energy drink consumption among individual adolescents and the potential that additional health and behavioural risks may be associated with consumption.

The effects of combined caffeine and glucose drinks on attention in the human brain

The objective of this research was to measure the effects of energising drinks containing caffeine and glucose, upon mental activity during sustained selective attention. Non-invasive electrophysiological brain recordings were made during a behavioural study of selective attention in which participants received either energising or placebo drinks. We tested specifically whether energising drinks have significant effects upon behavioural measures of performance during a task requiring sustained visual selective attention, as well as on accompanying components of the event-related potential (ERPs) related to information processing in the brain. Forty healthy volunteers were blindly assigned to receive either the energising drink or a similar-tasting placebo drink. The behavioural task involved identifying predefined target stimulus among rapidly presented streams of peripheral visual stimuli, and making speeded motor responses to this stimulus. During task performance, accuracy, reaction times and ongoing brain activity were stored for analysis. The energising drink enhanced behavioural performance both in terms of accuracy and speed of reactions. The energising drink also had significant effects upon the event-related potentials. Effects started from the enhancement of the earliest components (Cl/P1), reflecting early visual cortical processing in the energising-drink group relative to the placebo group over the contralateral scalp. The later N1, N2 and P3 components related to decision-making and responses were also modulated by the energising drink. Energising drinks containing caffeine and glucose can enhance behavioural performance during demanding tasks requiring selective attention. The behavioural benefits are coupled to direct effects upon neural information processing.

Caffeine can decrease subjective energy depending on the vehicle with which it is consumed and when it is measured

RATIONALE

Energy drinks contain glucose and caffeine, although in the longer term both adversely influence blood glucose homeostasis, with the unconsidered potential to have adverse consequences for cognition and mood.

OBJECTIVE

The objective of this study was to consider the influence on interstitial glucose levels, mood and cognition of drinks differing in their caffeine content and glycaemic load.

METHODS

Ninety minutes after a standard breakfast, a yoghurt-, glucose- or water-based drink, with or without 80 mg of caffeine, was consumed.

RESULTS

The consumption of caffeine negatively influenced glucose homeostasis: that is, irrespective of the vehicle, caffeine consumption resulted in elevated levels of blood glucose throughout the study. Thirty minutes after consuming caffeine and water, rather than water alone, greater subjective energy was reported. However, after 90 and 150 min, caffeine administered in water increased tiredness, hostility and confusion. In contrast, combining caffeine with a yoghurt-based drink increased energy, agreeableness and clearheadedness later in the morning. There were no effects of caffeine on ratings of mood when it was taken with glucose. Caffeine, irrespective of vehicle, resulted in better memory, quicker reaction times in the choice reaction time test and the working memory task, and better and quicker responses with the vigilance task.

CONCLUSION

Further research should consider how caffeine interacts with macronutrients and the timescale over which such effects occur.

An evaluation of the cognitive and mood effects of an energy shot over a 6h period in volunteers: a randomized, double-blind, placebo controlled, cross-over study

Energy drinks are widely available mostly containing glucose, and several have been demonstrated to improve alertness and cognitive function; these effects generally being identified 30-60min after administration. The present study assessed whether an energy shot without carbohydrates would affect major aspects of cognitive function and also mood in volunteers over a 6h time period. This randomized, double-blind, placebo-controlled,crossover study compared the acute effects of the energy shot with a matching placebo in 94 healthy volunteers. Cognitive function was assessed with a widely used set of automated tests of attention and memory. Mood was assessed with the Bond-Lader, Beck Anxiety Index, Beck Depression Index, Chalder Fatigue Scales (CFS), and the POMS. The volunteers were requested to limit their sleep to between 3 and 6h the night before each testing day. Compared to the placebo, the energy shot significantly improved 6 validated composite cognitive function measures from the CDR System as well as self-rated alertness; the benefits on 4 of the cognitive measures still remaining at 6h. The overall effect sizes of the performance improvements were in the small to medium range and thus notable in this field. In conclusion, an energy shot can significantly improve important aspects of cognitive function for up to 6h compared to placebo in partially sleep-deprived healthy volunteers.

International Society of Sports Nutrition position stand: energy drinks

Position Statement: The International Society of Sports Nutrition (ISSN) bases the following position stand on a critical analysis of the literature on the safety and efficacy of the use of energy drinks (ED) or energy shots (ES). The ISSN has concluded the following. 1. Although ED and ES contain a number of nutrients that are purported to affect mental and/or physical performance, the primary ergogenic nutrients in most ED and ES appear to be carbohydrate and/or caffeine. 2. The ergogenic value of caffeine on mental and physical performance has been well-established but the potential additive benefits of other nutrients contained in ED and ES remains to be determined. 3. Consuming ED 10-60 minutes before exercise can improve mental focus, alertness, anaerobic performance, and/or endurance performance. 4. Many ED and ES contain numerous ingredients; these products in particular merit further study to demonstrate their safety and potential effects on physical and mental performance. 5. There is some limited evidence that consumption of low-calorie ED during training and/or weight loss trials may provide ergogenic benefit and/or promote a small amount of additional fat loss. However, ingestion of higher calorie ED may promote weight gain if the energy intake from consumption of ED is not carefully considered as part of the total daily energy intake. 6. Athletes should consider the impact of ingesting high glycemic load carbohydrates on metabolic health, blood glucose and insulin levels, as well as the effects of caffeine and other stimulants on motor skill performance. 7. Children and adolescents should only consider use of ED or ES with parental approval after consideration of the amount of carbohydrate, caffeine, and other nutrients contained in the ED or ES and a thorough understanding of the potential side effects. 8. Indiscriminant use of ED or ES, especially if more than one serving per day is consumed, may lead to adverse events and harmful side effects. 9. Diabetics and individuals with pre-existing cardiovascular, metabolic, hepatorenal, and neurologic disease who are taking medications that may be affected by high glycemic load foods, caffeine, and/or other stimulants should avoid use of ED and/or ES unless approved by their physician.

Differential cognitive effects of energy drink ingredients: caffeine, taurine, and glucose

Energy drinks containing caffeine, taurine, and glucose may improve mood and cognitive performance. However, there are no studies assessing the individual and interactive effects of these ingredients. We evaluated the effects of caffeine, taurine, and glucose alone and in combination on cognitive performance and mood in 24-hour caffeine-abstained habitual caffeine consumers. Using a randomized, double-blind, mixed design, 48 habitual caffeine consumers (18 male, 30 female) who were 24-hour caffeine deprived received one of four treatments (200 mg caffeine/0 mg taurine, 0 mg caffeine/2000 mg taurine, 200 mg caffeine/2000 mg taurine, 0 mg caffeine/0 mg taurine), on each of four separate days, separated by a 3-day wash-out period. Between-participants treatment was a glucose drink (50 g glucose, placebo). Salivary cortisol, mood and heart rate were measured. An attention task was administered 30-minutes post-treatment, followed by a working memory and reaction time task 60-minutes post-treatment. Caffeine enhanced executive control and working memory, and reduced simple and choice reaction time. Taurine increased choice reaction time but reduced reaction time in the working memory tasks. Glucose alone slowed choice reaction time. Glucose in combination with caffeine, enhanced object working memory and in combination with taurine, enhanced orienting attention. Limited glucose effects may reflect low task difficulty relative to subjects' cognitive ability. Caffeine reduced feelings of fatigue and increased tension and vigor. Taurine reversed the effects of caffeine on vigor and caffeine-withdrawal symptoms. No effects were found for salivary cortisol or heart rate. Caffeine, not taurine or glucose, is likely responsible for reported changes in cognitive performance following consumption of energy drinks, especially in caffeine-withdrawn habitual caffeine consumers.

A survey of energy drinks consumption practices among student -athletes in Ghana: lessons for developing health education intervention programmes

BACKGROUND

Globally, young adults and college athletes are primary targets of the marketing campaigns of energy drink companies. Consequently, it is reported that young adults and college athletes consume energy drinks frequently. The purpose of this study was to determine the prevalence of energy drink consumption among student-athletes selected from seven public universities in Ghana. The study assessed the energy drink consumption patterns, types usually consumed, frequency of consumption and reasons why athletes consumed energy drinks.

METHODS

A total number of 180 student-athletes gave their consent to participate in the study and completed a questionnaire which was administered during an inter-university sports competition.

RESULTS

Most of the participants (62.2%) reported consuming at least one can of energy drink in a week. A high proportion (53.6%) of the respondents who drink energy drinks indicated that they did so to replenish lost energy after training or a competition. Other reasons given as to why energy drinks were consumed by the study participants included to provide energy and fluids to the body (25.9%), to improve performance (9.8%) and to reduce fatigue (5.4%).

CONCLUSION

These results suggest the need to plan health education programmes to particularly correct some wrong perceptions that athletes have regarding the benefits of energy drinks and also create awareness among student-athletes about the side effects of excessive intake of energy drinks.

Increased alcohol consumption, nonmedical prescription drug use, and illicit drug use are associated with energy drink consumption among college students

OBJECTIVES

This longitudinal study examined the prevalence and correlates of energy drink use among college students, and investigated its possible prospective associations with subsequent drug use, including nonmedical prescription drug use.

METHODS

Participants were 1,060 undergraduates from a large, public university who completed three annual interviews, beginning in their first year of college. Use of energy drinks, other caffeinated products, tobacco, alcohol, and other illicit and prescription drugs were assessed, as well as demographic and personality characteristics.

RESULTS

Annual weighted prevalence of energy drink use was 22.6%(wt) and 36.5%(wt) in the second and third year of college, respectively. Compared to energy drink non-users, energy drink users had heavier alcohol consumption patterns, and were more likely to have used other drugs, both concurrently and in the preceding assessment. Regression analyses revealed that Year 2 energy drink use was significantly associated with Year 3 nonmedical use of prescription stimulants and prescription analgesics, but not with other Year 3 drug use, holding constant demographics, prior drug use, and other factors.

CONCLUSIONS

A substantial and rapidly-growing proportion of college students use energy drinks. Energy drink users tend to have greater involvement in alcohol and other drug use and higher levels of sensation-seeking, relative to non-users of energy drinks. Prospectively, energy drink use has a unique relationship with nonmedical use of prescription stimulants and analgesics. More research is needed regarding the health risks associated with energy drink use in young adults, including their possible role in the development of substance use problems.