Adolescent caffeine consumption and self-reported violence and conduct disorder

Caffeine, Daytime Sleepiness, and Conduct Problems Among Early Adolescents: A Longitudinal Analysis

PURPOSE

Recent research suggests that caffeine use may promote a range of adjustment difficulties among adolescents, particularly during the middle school years. The effects of caffeine are particularly concerning given the increased use of high-dosage caffeine products, such as energy drinks, among youth. We investigated the influence of caffeine use on trajectories of conduct problems among early adolescents. Daytime sleepiness was tested as mediator of caffeine's effect.

METHODS

Hypotheses were tested with longitudinal (4 waves) data from 2,633 middle school students beginning in the Fall of sixth grade and concluding in the spring of seventh grade. All students in a single class cohort at 20 West Virginia middle schools were invited to participate.

RESULTS

Controlling for family affluence and management practices and pubertal development, use of more than 100 mg of caffeine significantly predicted linear increases in conduct problems over time (Est. = 0.23, p = .015). Increases in daytime sleepiness partially mediated this effect (Est. = 0.22, p = .002).

DISCUSSION

Caffeine use and daytime sleepiness are important vulnerability factors for the emergence of conduct problems.

Adolescent caffeine use and problematic school behavior: A longitudinal analysis of student survey data and teacher observations

INTRODUCTION

Caffeine is a psychostimulant possessing arousal, motor activation, and reinforcing properties, which is consumed daily by most adolescents aged 12-19 years. Although current understanding of the implications of adolescent caffeine consumption for school behaviors remains incomplete, studies have shown that in addition to acute effects of the drug, in common with other habit-forming psychoactive substances, regular use leads to physical dependence, evidenced by recurring negative withdrawal symptoms.

METHODS

Employing two waves of longitudinal data, we tested the prospective association between daily caffeine use and homeroom teacher-observed self-control and problem behavior in a sample of middle-school students in 20 schools in West Virginia in the United States. Caffeine was operationalized with two dichotomized variables, daily consumption of <100 mg, and daily consumption of >100 mg, versus no daily use. Gender, mother's education, family financial status, social support by primary caregiver and adults in school, and school climate, were applied as covariates in linear mixed models.

RESULTS

Daily caffeine use of >100 mg was robustly and inversely associated with self-control and positively associated with problem behavior.

CONCLUSIONS

Caffeine consumption and associated withdrawal symptoms may be an important factor in problematic school behavior among adolescents. Recent advent of highly concentrated caffeine products (e.g., caffeine "shots") commonly marketed directly at youth, should give rise to concerns including consideration about limiting caffeine consumption among children and youth.

Anger and associated risk and protective factors among rural American adolescents: Implications for violence prevention

Background

Adolescent violence in the United States is a prevalent public health problem and is understudied in rural settings. Anger is a significant risk factor for adolescent violence. To better craft adolescent violence interventions, it is important to examine anger and identify its most significant associated factors.

Aims

This study examined (1) self-reported anger changes over time for rural American adolescents; and (2) structural, community, interpersonal, and individual level factors that may contribute to anger.

Methods

We analyzed self-reported survey data from West Virginian middle schoolers (N = 2861) with anger as the outcome. Data was collected twice yearly from October 2020 through April 2023. Independent variables included perceptions of inequality, individual socioeconomic status (SES), neighborhood characteristics, family structure, support from adults at home and school, and harsh parenting.

Analysis

Generalized estimating equation Poisson regression models for main effects and gender interaction were used. Parameter estimates were exponentiated and interpreted as Rate Ratios (RR). Self-reported gender was an effect modifier.

Results

Significant main effects included perceived inequality (RR = 0.98, 95 % CI = 0.97-0.99), SES (RR = 0.99, 95 % CI = 0.98-0.99), supportive adults at school (RR = 0.99, 95 % CI = 0.98-0.99), primary caregiver support (RR = 0.99, 95 % CI = 0.98-0.99), and harsh parenting (RR = 1.10, 95 % CI = 1.05-1.05). Significant gender interaction terms included perceived harsh parenting (RR = 0.98, 95 % CI = 0.97-0.99) and supportive adults at school (RR = 1.01, 95 % CI = 1.00-1.02) for 'other' genders (i.e., participants identifying as neither boy nor girl) compared to boys.

Conclusions

Findings underline the importance of examining rural adolescent anger development and associated risk factors for designing prevention approaches to curb downstream violent behavior.

Aggression and the Big Five Personality Factors Among Fitness Practitioners and Pre-Workout Consumers

Background: The use of pre-workout supplements has surged among fitness practitioners, with various ingredients purported to enhance performance and recovery. This study aims to explore the potential link between pre-workout supplement consumption and aggression, as well as the correlation between the Big Five personality traits and aggression levels. Methods: The sample comprised 62 male fitness practitioners aged 20-55 years, divided into two groups: 32 pre-workout consumers and 30 non-consumers. Participants were assessed using the Buss and Perry Aggression Questionnaire and the NEO Five-Factor Inventory (NEO-FFI). Results: The results indicated no statistically significant differences in aggression levels between the supplement users and the control group. However, notable personality differences were observed, with pre-workout users showing lower Neuroticism and higher Agreeableness and Conscientiousness compared to non-users. Correlation analyses revealed a significant positive relationship between Neuroticism and all forms of aggression, while Agreeableness and Conscientiousness were negatively correlated with aggression. Conclusions: These findings suggest that personality traits may play a more substantial role in moderating aggression among pre-workout users than the supplements themselves. Further research is needed to clarify the potential long-term effects of pre-workout supplementation on aggression and personality dynamics.

Association between ultra-processed dietary pattern and bullying: the role of deviant behaviors

Background

Ultra-processed foods have been associated with several negative outcomes, but it is not clear whether they are related to bullying perpetration. Moreover, no previous study has investigated the potential role of deviant behaviors as a mediator of this association. Our objective was to evaluate the association between ultra-processed dietary pattern and bullying, and the mediating effect of deviant behaviors in this association, among school adolescents.

Methods

We used data from a representative sample of 9th grade Brazilian adolescents (N = 2,212) from the São Paulo Project for the social development of children and adolescents (SP-PROSO). Exploratory factor analysis was used to obtain the dietary patterns, through questions of frequency of consumption in the last week of several foods. The ultra-processed dietary pattern was considered as exposure. The outcomes were the types of bullying (any type, social exclusion, psychological/verbal aggression, physical aggression, property destruction, and sexual harassment). Deviant behaviors (mediator) were assessed through a score. Mediation analyses were carried out using logistic regression based on the KHB method.

Results

After adjusting for covariates, the mediating effect of deviant behaviors was found in the association between ultra-processed dietary pattern and all the types of bullying perpetration, especially for psychological/verbal aggression (39.4%). A small mediating effect of deviant behaviors in the association of ultra-processed dietary pattern with physical aggression (17.7%) and property destruction (18.5%) was observed, but this effect explained only a small portion of the total effect of such association (significant direct effect).

Conclusion

The ultra-processed dietary pattern was associated with bullying, and the association was mediated through deviant behaviors. Policies and actions for improving the adolescent's diet and managing the adoption of deviant and bullying behaviors by this public are required.

Clustering of Obesogenic Behaviors Associated With Bullying Roles Among 100,794 Adolescents

Obesogenic behaviors have been individually associated with bullying during adolescence. However, physical activity, sedentary behavior, and diet manifest themselves in synergy and even behavioral profiles in which positive and negative behaviors coexist can be more positively associated with psychosocial outcomes. The present study aimed to analyze the association between clusters of obesogenic behaviors and different bullying roles in Brazilian adolescents. This cross-sectional study used data from the Brazilian School-based Health Survey-PENSE, 2015. A total of 100,794 male and female adolescents of the ninth-grade elementary school participated in the study. Students responded to an electronic questionnaire. Clusters of obesogenic behavior consisted of physical activity, exposure to sedentary behavior, and diet, and the different roles in bullying were: participant, victim, bully, and bully-victim. Binary logistic regression with 95% confidence intervals (CI) was used for data analysis (p < .05). Multiple adjustments and complex sampling procedures were employed. Adolescents in the cluster "Health-promoting sedentary behavior and Diet" had reduced chances of participating in bullying (odds ration [OR] = 0.70; 95% CI [0.64, 0.76]), of being a victim (OR = 0.87; 95% CI = 0.76-0.99), and being the bully (OR = 0.65; 95% CI [0.59, 0.71]); and those from the cluster "Health-promoting physical activity and Diet" had reduced chances of participating (OR = 0.81; 95% CI [0.76, 0.87]), being a victim of bullying (OR = 0.86; 95% CI [0.76, 0.98]), being the bully (OR = 0.79; 95% CI [0.72, 0.85]), and being a bully-victim (OR = 0.74; 95% CI [0.61, 0.90]), when compared to those from the "health-risk" cluster in the adjusted analysis. Clusters of obesogenic behavior may reduce adolescent bullying: victim, bully, and bully-victim benefit when exposed to healthier behavioral profiles. The school setting must recognize bullying as a problem and therefore simultaneously promote multi-component interventions to tackle physical activity, sedentary behavior, and eating behavior. Outcomes other than obesity should be acknowledged when promoting obesogenic behaviors.

Use of Caffeine-Containing Energy Drinks by Japanese Middle School Students: A Cross-Sectional Study of Related Factors

Excessive consumption of caffeine negatively affects individuals' health. Therefore, we studied the use of energy drinks and the conditions associated with it among Japanese secondary school students. Participants were 236 students in grades 7-9 who completed anonymous questionnaires at home in July 2018. We measured the basic attributes and dietary, sleeping, and exercise habits. We used Chi-squared tests to compare differences between users and non-users of energy drinks. Logistic regression analyses were used to elucidate the complex association between the variables. The results showed that boys were more willing to consume energy drinks than girls. The reasons were 'feeling fatigued', 'needing to stay awake', 'for curiosity', and 'to quench one's thirst'. Among boys, the following were associated with the use of EDs. Buying their own snacks , not understanding nutritional labels on foods, high caffeinated beverage intake, late bed-times on weekdays, always waking up at about the same time, and weight. Health guidance is needed to prevent overconsumption and dependence on energy drinks. The cooperation of parents and teachers is needed to achieve these goals.

Effects of Caffeine and Caffeinated Beverages in Children, Adolescents and Young Adults: Short Review

The prevalence of ED consumption has increased over the past 10–15 years. Studies describing the effects of caffeine and caffeinated beverages show confusing results, so it seems important to regularly summarize the available facts, and in more detail. By a thorough analysis of more than 156 scientific papers, the authors describe the molecular background of absorption, as well as the positive and negative effects of different dosages of caffeine, just like its effects in physical activity and performance. ED and EDwA consumption is a regular habit of not only adults, but nowadays even of children and adolescents. There are no safe dosages described of caffeine or ED consumption for children. There are no positive short- or long-term effects of these compounds/products concerning developing brain functions, psycho-motor functions, or social development. Instead, there are many unpleasant side effects, and symptoms of regular or higher-dose ED consumption, especially at younger ages. This mini review describes many details of these unpleasant side effects, their severity, and motivations for consuming these compounds/products. In a quantitative research in Hungary (10–26 years, mean age: 15.6 ± 3.8 y, 1459 subjects, randomly chosen population), a survey based on a questionnaire asking people about their ED consumption habits was conducted. According to the data, 81.8% of the participants consumed EDs at least once, and 63.3% tried several products of the kind. A positive correlation was found between age and consumption (p < 0.001). The results show that a high proportion of this group often consumed EDwA, in many cases leading to harmful side-effects of caffeine overdose. In a sample of Hungarian high school and college students (17–26 years), ED consumption matched the international data, and only 19.7% of respondents did not use EDs at all (had never tasted an ED in their life).

Adolescent caffeine consumption and aggressive behavior: A longitudinal assessment

Background: Adolescent caffeine consumption has been linked to aggressive behaviors, although no longitudinal tests have been reported to date. The purpose of this study was to test the longitudinal relations between daily adolescent caffeine consumption and aggressive behaviors. Methods: Two waves of survey data collected 12 months apart in the spring of 2018 and 2019, from the 2004 birth cohort in the Icelandic LIFECOURSE study, were analyzed using structural equation modeling (N = 2,278). Both direct and mediated models were employed. Results: Caffeine use at time 1 (T1) was associated with aggressive behavior at time 2 (T2) (β = .12, p < .001) independent of aggressive behavior at T1. A considerable added relation was observed between caffeine at T1 and aggressive behavior at T2 via indirect (i.e., mediated) effects of aggressive behavior at T1 (standardized β = .20, p < .001). Over 64% of the standardized total effect (β = .31) observed between caffeine at T1 and aggressive behavior at T2 was due to mediation. Conclusion: Adolescent caffeine consumption forecasts aggressive behaviors. Caffeine use at T1 increased the likelihood of self-reported aggressive behaviors 12 months later irrespective of level of reported aggressive behavior at T1 while controlling for common confounders.

Energy Drink Consumption, Depression, and Salutogenic Sense of Coherence Among Adolescents and Young Adults

The prevalence of energy drink consumption has increased in Hungary over the past 10–15 years. This study assesses the frequency, motivations, and adverse effects of energy drink consumption, and examines how the process of becoming a regular consumer is connected with sense of coherence and depression symptoms. A total of 631 high school and college students were assessed using the Depression Scale (BDS-13) and Sense of Coherence Scale (SOC-13). Logistic regression models were fit to test the effect of and links between factors influencing addiction to energy drink use. A total of 31.1% (95% CI: 27.4–34.7) of those surveyed consumed energy drinks, 24.0% of those affected consumed the energy drink with alcohol, 71.4% (95% CI: 64.7–77.3) experienced adverse effects following energy drink consumption, and 10.2% (95% CI: 6.7–15.2) experienced at least four symptoms simultaneously. The most common motivations of consumption were fatigue, taste, and fun. Obtained by multivariate logistic regression models, after adjustment for sex and age, SOC and tendency to depression had a significant influence on the respondents’ odds of addiction. The tendency to depression increases the chances of addiction, while a strong sense of coherence diminishes the effects of depression. Young people in Hungary have been shown to consume energy drinks in quantities that are detrimental to their health. Complex preventive measures and programs are needed to address the problem. Families and educators should strive to instill a strong sense of coherence in children from an early age.

Chronic caffeine exposure in adolescence promotes diurnal, biphasic mood-cycling and enhanced motivation for reward in adult mice

Adolescent's consumption of caffeine and caffeinated beverage is increasing, yet little is known about the consequences of chronic caffeine exposure during the critical development period of adolescence. In the present study, we investigated the effect of beginning chronic caffeine consumption in adolescence on locomotor, mood, sensorimotor gating, and reward seeking behaviors through adolescence and in adulthood. During the light cycle, caffeine exposed mice exhibited hypoactivity in a novel open-field box and increased anxiety-like and depressive-like behaviors, while maintaining normal home cage locomotor activity. In contrast, during the dark cycle caffeine exposed mice displayed normal locomotor activity in a novel open-field box with hyperactive home cage activity. Interestingly, we found that caffeine exposed mice also showed enhanced prepulse inhibition during the light cycle whereas they displayed a deficit of prepulse inhibition during the dark cycle. Reward seeking for sucrose was higher in caffeine exposed than control mice during the light cycle. Additionally, when granted 24 -h access to ethanol as adults, caffeine exposed mice consumed more ethanol in the absence of acute caffeine use. Altogether, mice that consumed chronic caffeine beginning in adolescence had increased reward seeking and exhibited a circadian-dependent pattern of mood fluctuations in adulthood.

Energy drinks in children and adolescents: demographic data and immediate effects

Energy drinks consumption has become increasingly common in the last few years, despite evidence associating these products with vast adverse health effects. This led us to explore the phenomenon of energy drinks consumption in adolescents in the Israeli Arab population of the Nazareth area (Northern Israel), examining their awareness of risks associated with consumption of energy drinks, investigating their immediate effects on the body. Our study revealed that the consumption of energy drinks is very common in adolescents of both sexes, though more common in boys. Of 375 students who filled out the questionnaire, 206 reported that they consumed energy drinks (55%), 91 were male (44.4%), and 115 were female (55.6%). In the experimental stage of this study, we found that energy drinks significantly increased systolic blood pressure in most participants within a brief period of time after drinking.Conclusion: Given the prevalence of energy drinks consumption and their side effects, it is important to increase awareness of the risks associated with their regular use and to combat this phenomenon through the education system in schools. What is Known: • Energy drinks consumption has become popular and frequent among adolescents across the world. • The immediate effects of energy drinks in children and adolescents are poorly described. What is New: • Religious and social norms are not a barrier to ED consumption among the varied investigated population. • Our study describes the immediate effect of energy drinks during the first 2 h after consumption, revealing systolic blood pressure to be significantly increased.

Investigating associations between caffeinated beverage consumption and later alcohol consumption among early adolescents

Previous research has demonstrated that caffeinated beverage consumption predicts alcohol consumption among early adolescents. This study aimed to investigate this association in two ways: (1) by examining if this association remained significant once other established risk factors for alcohol were adjusted for statistically; and (2) by considering three possible moderators of this association: gender, sensation-seeking, and parental monitoring. Data from the Camden Youth Development Study, a longitudinal, community-based study of middle-school students, were used. Youth were initially assessed in 6th and 7th grade and followed-up 16 months later. Self-reports of frequency of energy drink, coffee, and alcohol consumption, as well as sensation-seeking, perceived peer and best friend alcohol use, alcohol expectancies, and parental monitoring, were used. Results indicated that both energy drink and coffee consumption predicted later alcohol consumption, even after adjusting for other risk factors for alcohol consumption. Parental monitoring was a significant moderator of this link, such that youth who consumed energy drinks and reported low parental monitoring were particularly at risk for later alcohol consumption. These findings indicate that the link between earlier caffeine consumption and later alcohol consumption is not simply due to the co-occurrence of caffeine consumption with other risk factors for alcohol use. In addition, risk associated with early energy drink consumption appears to be particularly pronounced for youth in families characterized by low parental monitoring.

Review: Trends, Safety, and Recommendations for Caffeine Use in Children and Adolescents

OBJECTIVE

Caffeine use is common in children and adolescents, but the recommendations for safe consumption are based on decades-old data collected exclusively in adults. Increased availability of caffeine-containing products and a concerted marketing effort aimed at children and adolescents, has increased interest in understanding the physiological, behavioral, and psychological effects of caffeine within this population. This manuscript provides a review of the literature concerning trends and safety of ingested caffeine in children and adolescents.

METHOD

A search of the National Library of Medicine database was conducted using the terms caffeine, children, adolescents, and safety, in addition to tailored searches on specific topics using combinations of search terms such as energy drinks, cardiovascular, mood, cognitive, mental health, sleep, and regulations.

RESULTS

The majority of the literature reviewed here suggests that typical, moderate caffeine consumption in children and adolescents is relatively safe, but that higher doses of caffeine consumption (>400 mg) can cause physiological, psychological, and behavioral harm, in particular in subgroups of children, such as those with psychiatric or cardiac conditions. More attention is being paid to the potential adverse effects of both acute and chronic caffeine use, and additional regulations surrounding the sale and marketing of highly caffeinated beverages are now being considered.

CONCLUSION

More research is needed to fill in gaps in our knowledge, including understanding the relationship between caffeine use and initiation of other substances, such as cigarettes, alcohol, or marijuana, identifying individuals at risk for caffeine toxicity, and developing harm-reduction strategies.

Adolescent habitual caffeine consumption and hemodynamic reactivity during rest, psychosocial stress, and recovery

OBJECTIVE

Most adolescents regularly consume caffeine. Whereas observational studies have suggested that coffee may be cardio-protective, pharmacological experimentation with adults shows that caffeine at dietary doses increases blood pressure, thereby implicating regular caffeine consumption as a potential source of harm for cardiovascular health. The present study was in response to the dearth of caffeine research among younger consumers. It was hypothesised that compared to the consumption of little or no caffeine, adolescents who habitually consume caffeine have overall higher blood pressure and increased vascular resistance.

METHOD

Using a quasi-experimental design, continuous measurements of blood pressure, cardiac output, and total peripheral resistance were taken non-invasively from adolescents (n = 333) aged 14-15 years and 18-19 years who reported "low", "moderate", or "high" levels of caffeine intake. Measurements were conducted when participants generally had negligible or low systematic caffeine levels while at rest, during stress, and during recovery from stress.

RESULTS

Whereas habitual caffeine consumption did not predict blood pressure level, higher caffeine intake was associated with modestly increased vascular resistance during all phases of the experiment (i.e., at rest, during stress, and during recovery from stress).

CONCLUSIONS

Present findings are important because they suggest that early exposure to caffeine may lead to persistent increases in vascular resistance, which in turn is an acknowledged risk factor for the development of hypertension. These results highlight the need for further studies of adolescents to determine the robustness of any persistent caffeine-related hemodynamic effects, and the implications such effects could have for long-term cardiovascular health.

Does early exposure to caffeine promote smoking and alcohol use behavior? A prospective analysis of middle school students

BACKGROUND AND AIMS

Despite the negative consequences associated with caffeine use among children and youth, its use is increasingly widespread among middle school students. Cross-sectional studies reveal links between caffeine and other substance use. The potential for caffeine use to confer increased vulnerability to substance use, however, has not been investigated using prospective designs. We hypothesized that caffeine use at baseline would be associated positively with increased alcohol use, drunkenness, smoking and e-cigarette use.

DESIGN

Prospective cohort study with 12 months separating baseline from follow-up.

SETTING

West Virginia, USA.

PARTICIPANTS

Middle school students (6th and 7th grades; n = 3932) in three West Virginia (WV) counties provided data at baseline and follow-up 12 months later.

MEASUREMENTS

Youth self-reported their use of caffeine from multiple sources (e.g. soda, energy drinks, coffee and tea), cigarette smoking, electronic cigarette use, alcohol use and drunkenness.

FINDINGS

Cross-lagged path models for individual substance use categories provided a good fit to the data. Controlling for demographic variables and other substance use at baseline, caffeine at time 1 (T1) was associated positively with T2 cigarette smoking (β = 0.27, P = 0.001), e-cigarette use (β = 0.21, P = 0.001), alcohol use (β = 0.17, P = 0.001) and drunkenness (β = 0.15, P = 0.001). Conversely, non-significant relations emerged between three of four substances at T1 and caffeine at T2. Positive relations were found between e-cigarette use at T1 and caffeine use at T2 (β = 0.07, P = 0.006). These findings were supported by an omnibus model with all substances included. Specifically, significant relations were observed between caffeine at T1 and all substance use outcomes at T2, whereas no significant relations were observed between substance use and caffeine over time.

CONCLUSIONS

Caffeine may promote early use of other types of substances among middle school-aged adolescents.

Trajectories of energy drink consumption and subsequent drug use during young adulthood

BACKGROUND

Highly caffeinated energy drinks (EDs) are popular with adolescents and young adults, but longitudinal consumption patterns are poorly understood especially in relation to other substance use.

METHODS

ED and other substance use were assessed annually (modal ages 21-25) among a sample (n=1099) who were originally recruited as first-year college students (modal age 18). Trajectory groups were derived based on probability of past-year use during ages 21-24, and compared for possible differences in substance use outcomes at age 25, holding constant demographics, sensation-seeking, other caffeine consumption, and age 21 substance use.

RESULTS

From age 21-25, ED consumption declined in both annual prevalence [62.5%wt to 49.1%wt (wt=weighted)] and frequency of use among consumers (35.2-26.3 days/year). Yet individuals exhibiting a Persistent trajectory (51.4%) of consumption outnumbered those with Non-Use (20.6%), Intermediate (17.4%), or Desisting (10.6%) trajectories. Age 25 cocaine use, nonmedical use of prescription stimulants (NPS), and alcohol use disorder (AUD) risk were significantly associated with trajectory group membership, with Persistent and Intermediate groups exhibiting the highest risk for such outcomes, even accounting for prior substance use and other risk factors. Neither marijuana nor tobacco use were associated with group membership.

CONCLUSIONS

The typical pattern of ED consumption among this sample was sustained use throughout young adulthood. Such individuals appear to be at high risk for adverse substance use outcomes, and results suggest possible specificity regarding cocaine use and NPS, and AUD risk. More research is needed to understand the mechanisms underlying the connection between ED and substance use.

Interactions Between Energy Drink Consumption and Sleep Problems: Associations with Alcohol Use Among Young Adolescents

Background: Energy drink consumption and sleep problems are both associated with alcohol use among adolescents. In addition, caffeine consumption (including energy drinks) is associated with sleep problems. However, information about how these three constructs may interact is limited. The goal of this study was to examine potential interactions between energy drink consumption and sleep problems in the concurrent prediction of alcohol use among young adolescents. Coffee and soda consumption were also examined for comparison. Methods: Participants from the Camden Youth Development Study were included (n = 127; mean age = 13.1; 68% Hispanic, 29% African American) and questionnaire measures of frequency of caffeinated beverage consumption (energy drinks, coffee, and soda), sleep (initial insomnia, sleep disturbances, daytime fatigue, and sleep duration), and alcohol consumption were used. Regression analyses were conducted to examine interactions between caffeinated beverage consumption and sleep in the concurrent prediction of alcohol use. Results: Energy drink consumption interacted with initial insomnia and daytime fatigue to concurrently predict particularly frequent alcohol use among those with either of these sleep-related problems and energy drink consumption. The pattern of results for coffee consumption was similar for insomnia but reached only a trend level of significance. Results of analyses examining soda consumption were nonsignificant. Conclusions: Young adolescents who both consume energy drinks and experience initial insomnia and/or daytime fatigue are at particularly high risk for alcohol use. Coffee consumption appears to be associated with similar patterns. Longitudinal research is needed to explain the developmental pathways by which these associations emerge, as well as mediators and moderators of these associations.

The Safety of Ingested Caffeine: A Comprehensive Review

Caffeine is the most widely consumed psychoactive drug in the world. Natural sources of caffeine include coffee, tea, and chocolate. Synthetic caffeine is also added to products to promote arousal, alertness, energy, and elevated mood. Over the past decade, the introduction of new caffeine-containing food products, as well as changes in consumption patterns of the more traditional sources of caffeine, has increased scrutiny by health authorities and regulatory bodies about the overall consumption of caffeine and its potential cumulative effects on behavior and physiology. Of particular concern is the rate of caffeine intake among populations potentially vulnerable to the negative effects of caffeine consumption: pregnant and lactating women, children and adolescents, young adults, and people with underlying heart or other health conditions, such as mental illness. Here, we review the research into the safety and safe doses of ingested caffeine in healthy and in vulnerable populations. We report that, for healthy adults, caffeine consumption is relatively safe, but that for some vulnerable populations, caffeine consumption could be harmful, including impairments in cardiovascular function, sleep, and substance use. We also identified several gaps in the literature on which we based recommendations for the future of caffeine research.

Regular energy drink consumption is associated with the risk of health and behavioural problems in adolescents

Consumption of energy drinks has become popular and frequent among adolescents across Europe. Previous research showed that regular consumption of these drinks was associated with several health and behavioural problems. The aim of the present study was to determine the socio-demographic groups at risk for regular energy drink consumption and to explore the association of regular energy drinks consumption with health and behavioural problems and negative school experiences in adolescents. Data from the Health Behaviour in School-aged Children Study conducted in 2014 in Slovakia were analysed. We assessed socio-demographic characteristics, energy drink consumption, health and behavioural problems and negative school experiences based on self-reports from 8977 adolescents aged 11-15 years (mean age/standard deviation 13/1.33; 50.0% boys). The prevalence of regular energy drink consumption in the present sample was 20.6% (95%CI: 20%-21%). Regular energy drink consumption was more frequent among boys and older adolescents. Adolescents with a medium-level family affluence were less likely to drink energy drinks regularly. Adolescents who consumed energy drinks regularly had more health and behavioural problems and negative school experiences.

CONCLUSION

Adolescents drinking energy drinks are at risk of a wide range of negative outcomes and should be specifically addressed by preventive interventions. What is Known • Energy drink consumption has become popular and frequent among adolescents across Europe. • There is growing evidence that energy drink consumption is related to negative social, emotional and health outcomes, but only a few studies have explored this relationship in adolescents. What is New • Regular energy drink consumption was more frequent among boys and adolescents reporting low family affluence and increased with age. • Adolescents reporting regular energy drink consumption were in higher risk to suffer from health and behavioural problems and negative school experiences.

The Relationship Between Caffeine, Sleep, and Behavior in Children

STUDY OBJECTIVES

To examine caffeine consumption from various dietary sources in a cohort of Australian children and the relationship between caffeine consumption, sleep, and daytime behavior.

METHODS

Children aged 8 to 12 years and their parents/guardians completed a battery of questionnaires. Children completed a caffeine questionnaire while parents completed questionnaires regarding demographics, sleep, and behavior.

RESULTS

The final sample consisted of 309 children (mean ± standard deviation [SD] age 10.6 ± 1.3 years, male = 48%) and corresponding parent reports. On average a mean ± SD 10.2 ± 17.4 mg/day of caffeine was consumed with a range of zero to 151 mg/day. Of the children who consumed caffeine (87% of the sample), the largest contributor was coffee and tea; making up 41% of total caffeine intake, and sodas (soft drinks) contributed to 40% of caffeine intake. Total caffeine consumption was significantly associated with sleep routine (r = 0.152); morning tiredness (r = 0.129); restless sleep (r = 0.113); and internalizing behavioral problems (r = 0.128). Using path analysis, caffeine consumption was positively associated with morning tiredness (β = 0.111, P = .050) which was positively associated with internalizing behaviors (β = 0.432, P < .001). The addition of sleep routine and restless sleep to the model led to a complete mediation of caffeine consumption on morning tiredness, as well as a partial mediation of the association between morning tiredness and internal behaviors.

CONCLUSIONS

In 8- to 12-year-olds the primary sources of caffeine are coffee/tea and sodas. Overall mean caffeine consumption is small by adult standards but has an effect on behavior and sleep in children. The effect on behavior is mediated by disrupted sleep, indicating that caffeine is a contributor to sleep problems and related behavior in children.

Caffeine Consumption and General Health in Secondary School Children: A Cross-sectional and Longitudinal Analysis

Although caffeine is sometimes associated with beneficial effects in adults, the substance may be dangerous if intake is too high. This concern is particularly relevant in regards to children and adolescents, as consumption of energy drinks may be particularly high in such populations. For this reason, the current study examined data from the Cornish Academies Project to determine whether caffeine intake in secondary school children was related to responses to a single-item measure of general health. Two cross-sections of data were available: questionnaires were completed by 2030 at baseline, by 2307 at 6-month follow-up, and by 1660 at both time-points. Relationships were, therefore, explored both cross-sectionally and longitudinally. High caffeine consumption (i.e., 1000 mg/week) was associated with low general health in both cross-sections of data, and analyses of individual caffeine sources suggested that the effects related specifically to cola and energy drinks. However, after controlling for additional aspects of diet, demography, and lifestyle, total weekly intake only remained significantly associated with general health at the latter time-point. Further to this, null findings from cross-lag and change-score analyses suggest that caffeine and general health were unlikely to be causally linked in this sample. However, due to methodological limitations, such as the two cross-sections of data being collected only 6 months apart, it is suggested that further longitudinal and intervention studies are required in order for firm conclusions to be drawn.

Consuming energy drinks at the age of 14 predicted legal and illegal substance use at 16

AIM

This study examined whether consuming energy drinks at the age of 14 predicted substance use at 16.

METHODS

We followed 621 youths from an area of Switzerland who completed a longitudinal online survey in both 2012 and 2014 when they were 14 and 16 years of age. At 14, participants, who were divided into nonenergy drink users (n = 262), occasional users (n = 183) and regular users (n = 176), reported demographic, health-related and substance use data. Substance use at 16 was assessed through logistic regression using nonusers as the reference group and controlling for significant variables at 14.

RESULTS

At the bivariate level, energy drink consumption was associated with substance use at both 14 and 16. Energy drink consumers were also more likely to be male, older, less academic, sleep less on schooldays and live in an urban area. In the multivariate analysis, smokers, alcohol misusers and cannabis users at the age of 16 were significantly more likely to have been regular energy drink users at the age of 14.

CONCLUSION

Consuming energy drinks at 14 years of age predicted using legal and illegal substances at 16. Health providers should screen young adolescents for energy drink use and closely monitor weekly users.

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.

Young adolescents who combine alcohol and energy drinks have a higher risk of reporting negative behavioural outcomes

OBJECTIVES

To explore whether young adolescents consuming alcohol and energy drinks combined were more likely to report negative behavioural outcomes than their peers who drink only one type of these beverages or are abstinent.

METHODS

We analysed data on a representative sample of Slovak adolescents 8502 adolescents (mean age 13.21, 49.4 % boys) from the 2014 Health Behaviour in School-aged Children cross-sectional study. We assessed the associations of alcohol and energy drinks consumption with negative outcomes and their potential synergy, as measured by the synergy index (SI).

RESULTS

Adolescents consuming both alcohol and energy drinks were at higher risk of negative behavioural outcomes than their peers who drank only alcohol or energy drinks or were non-consumers. Consumers of alcohol and energy drinks were highly prone to be involved in fighting-the joint association of alcohol and energy drinks consumption was greater than sum of its associations separately in relation to fighting (SI 1.49; 95 % confidence interval 1.03-2.16).

CONCLUSIONS

Preventive strategies should aim at increasing awareness of negative behavioural outcomes-especially aggressive behaviour associated with alcohol and energy drinks consumption among young adolescents.

Energy drink consumption and substance use risk in middle school students

OBJECTIVES

Energy drink (ED) sales have increased greatly in recent years and ED is now a common topic in health behavior research. Most studies work with samples of college students and/or young adults and to a lesser degree with high school students. Research is lacking on ED consumption in younger users. The purpose of this study was to fill this gap and assess the prevalence of ED consumption in a sample of middle school students as well to analyze the relationships between ED use and illicit and licit drug use in girls and boys of this age.

METHOD

We use cross-sectional school-survey data from 6-8th grade students in three US mid-Atlantic schools conducted in September to November 2014 (N = 1152, response rate: 82.4%).

RESULTS

Approximately 20% of participants had consumed ED and 10% had smoked cigarettes. Almost 14% had used alcohol at least once in their lifetime and 5.5% marijuana. Boys were more likely than girls to have used ED but no gender difference was observed in the prevalence of illicit substances. However, ED use was positively related to smoking and alcohol use among both genders, but also to several forms of illicit drug use among girls.

CONCLUSION

ED consuming girls are particularly prone to also use illicit substances. This is the first survey-type study which reports a positive relationship between ED consumption with both licit and illicit drug use in middle school-aged girls and boys.

Energy Drink and Coffee Consumption and Psychopathology Symptoms Among Early Adolescents: Cross-Sectional and Longitudinal Associations

Background: Little is known about possible links between energy drink use and psychopathology among youth. This study examined cross-sectional and longitudinal associations between energy drink consumption and psychopathology among early adolescents. In addition, associations between psychopathology and coffee consumption were examined to assess whether findings were specific to energy drinks or also applied to another commonly used caffeinated beverage. Methods: One hundred forty-four youth who participated in the Camden Youth Development Study (72 males; mean age 11.9 at wave 1; 65% Hispanic, 30% African American) were assessed using self-report measures of frequency of energy drink and coffee consumption and depression, anxiety, conduct disorder (CD) symptoms, and teacher reports of attention-deficit hyperactivity disorder (ADHD). Youth (92%) were reassessed 16 months later. Results: Concurrently, energy drink and coffee consumption were associated with similar psychopathology symptoms; when the other beverage was adjusted for, energy drinks remained associated with CD and coffee remained associated with panic anxiety. Initial energy drink consumption predicted increasing ADHD and CD over time, though the association with CD dropped to a trend level of significance when coffee was adjusted for. Initial levels of hyperactive ADHD predicted increasing coffee consumption over time; this association remained when energy drinks were controlled. Social anxiety was associated with less increase in energy drink consumption over time, controlling for coffee. Conclusion: Energy drink and coffee consumption among early adolescents are concurrently associated with similar psychopathology symptoms. Longitudinally, the associations between these beverages and psychopathology differ, indicating that these substances have differing implications for development over time.

Breakfast and Energy Drink Consumption in Secondary School Children: Breakfast Omission, in Isolation or in Combination with Frequent Energy Drink Use, is Associated with Stress, Anxiety, and Depression Cross-Sectionally, but not at 6-Month Follow-Up

A considerable amount of research suggests that breakfast omission and the frequent use of caffeinated energy drinks may be associated with undesirable effects, and particularly so in children and adolescents. The current paper presents cross-sectional and longitudinal data from the Cornish Academies Project to investigate the effects of consuming energy drinks and missing breakfast on stress, anxiety, and depression in a cohort of secondary school children from the South West of England. Questionnaires were administered at two time-points (spaced 6 months apart) to collect information relating to diet and lifestyle over the previous 6 months. Demographic and school data were acquired through the School Information Management System, and single-item measures of stress, anxiety, and depression were administered at the second time-point only. Associations between breakfast and energy drink consumption and stress, anxiety, and depression were investigated, and a multivariate approach was taken so that additional variance from diet, demography, and lifestyle could be controlled for statistically. Cross-sectional analyses showed that breakfast omission was consistently associated with negative outcomes, and that this was largely observed for both those who frequently consumed energy drinks and those who did not. However, cross-lag analyses showed that neither breakfast omission or energy drink consumption, alone or in combination, was predictive of stress, anxiety, or depression at 6-month follow-up. This suggests that associations between breakfast and mental health may be bi-directional rather than breakfast being the causal factor.

Caffeine consumption and self-assessed stress, anxiety, and depression in secondary school children

Previous research suggests that effects of caffeine on behaviour are positive unless one is investigating sensitive groups or ingestion of large amounts. Children are a potentially sensitive subgroup, and especially so considering the high levels of caffeine currently found in energy drinks. The present study used data from the Cornish Academies Project to investigate associations between caffeine (both its total consumption, and that derived separately from energy drinks, cola, tea, and coffee) and single-item measures of stress, anxiety, and depression, in a large cohort of secondary school children from the South West of England. After adjusting for additional dietary, demographic, and lifestyle covariates, positive associations between total weekly caffeine intake and anxiety and depression remained significant, and the effects differed between males and females. Initially, effects were also observed in relation to caffeine consumed specifically from coffee. However, coffee was found to be the major contributor to high overall caffeine intake, providing explanation as to why effects relating to this source were also apparent. Findings from the current study increase our knowledge regarding associations between caffeine intake and stress, anxiety, and depression in secondary school children, though the cross-sectional nature of the research made it impossible to infer causality.

Caffeine Awareness in Children: Insights from a Pilot Study

STUDY OBJECTIVES

Caffeine, a commonly consumed psychoactive substance, can have significant effects on sleep. Caffeine intake among children is increasing, mainly in the form of sodas. However, adolescent caffeine consumers may lack knowledge about the caffeine content in common beverages. If true, this very fact may hamper the assessment of the effects of caffeine consumption on sleep in children if such assessments are a priori dependent on responders being able to reliably distinguish between caffeinated and noncaffeinated beverages. This preliminary study investigated adolescents' caffeine knowledge and intake at a Cleveland-area public middle school.

METHODS

Seventh- and eighth-grade students were surveyed using: (1) the Caffeine Literacy and Sleep Study (CLASS), a 15-question pilot instrument designed to assess caffeine knowledge and intake by type, quantity and timing, as well as sleep habits; and (2) the Cleveland Adolescent Sleepiness Questionnaire (CASQ), a validated survey measuring excessive daytime sleepiness in adolescents. These questionnaires were distributed and collected during a specified class period.

RESULTS

Of the 635 seventh- and eighth-grade students who attended school on the day of the study, 555 (87%) participated. Lack of knowledge about caffeine content of particular drinks was noted in seventh and eighth graders of both sexes with nearly 29% unaware that their favorite drinks contain caffeine and more than 50% unable to correctly identify the drinks with the most caffeine. A low percentage of students correctly identified light-colored sodas lacking caffeine: 7-Up (24.1%), Sierra Mist (38.9%), ginger ale (39.8%), Sprite (39.8%), and Fresca (53.7%). The percentages of students correctly identifying caffeinated light-colored beverages were: Arizona Green Tea (43.5%), Mello Yellow (50.9%), and A&W cream soda (67.6%). However, Mountain Dew was correctly identified by most (93.5%) as caffeinated.

CONCLUSIONS

Students were not consistently able to identify caffeine content or lack thereof in some common beverages. The results of this pilot study show that caffeine literacy in adolescents warrants further investigation and educational intervention.

Energy drink consumption and later alcohol use among early adolescents

INTRODUCTION

Little is known about the association between energy drink and other substance use in early adolescence despite the fact that the consumption of energy drinks during this developmental period is becoming increasingly common. The aim of this study was to examine concurrent and longitudinal associations between energy drink and alcohol use among middle school students. In addition, sensation seeking and parental monitoring were examined as factors that could potentially explain any associations found.

METHODS

A sample of 144 youth participating in the Camden Youth Development Study was utilized. Self-report questionnaire data was collected over a 16-month period.

RESULTS

Frequency of energy drink use at the initial assessment predicted increases in frequency of alcohol use 16 months later (adjusting for initial frequency of alcohol use). Levels of parental monitoring partially accounted for this association; in contrast, there was no evidence that sensation seeking was related to this association.

CONCLUSION

Youth who consume energy drinks in early adolescence are at risk for alcohol use later; this may be partially related to low levels of parental monitoring being associated with the consumption of both substances. Future research is needed to further explain this association; this may lead to opportunities for early intervention for youth at high risk for alcohol use.

A gender-specific analysis of adolescent dietary caffeine, alcohol consumption, anger, and violent behavior

Self-reported dietary caffeine and alcohol consumption were examined in relation to anger and violent behavior in Icelandic tenth-graders. Structural equation modeling (SEM) was used to investigate direct and indirect effects of measured and latent variables in the population sample of 3,670, controlling for parental financial standing, family structure, ADHD, and peer delinquency. Gender differences were observed that have not been reported previously, especially in relation to anger as a possible mediator of violent behavior against a background of caffeine and alcohol consumption. Study findings suggest the need to take account of caffeine consumption in relation to adolescent anger and violence.

Ostracising caffeine from the pharmacological arsenal for attention-deficit hyperactivity disorder--was this a correct decision? A literature review

Caffeine is one of the most widespread psychotropic substances in the world. It exerts multiple effects on the brain including adenosine receptor antagonism, and thereby has been found to modulate aspects of cognition, including attention, in animal models and in healthy human volunteers. This review considers what is known of the effects of caffeine on symptoms and cognitive functions in attention-deficit hyperactivity disorder (ADHD), a prototypical disorder of cognitive dysfunction. We consider the merits of investigating further caffeine's therapeutic potential as a monotherapy or as an adjunctive agent in ADHD. The potential benefits of re-opening a dialogue regarding the use of caffeine in ADHD clinical practice are highlighted, along with potential implications for the use of adenosine receptor antagonists in ADHD and other disorders characterised by cognitive impairment.

The suitability of caffeinated drinks for children: a systematic review of randomised controlled trials, observational studies and expert panel guidelines

BACKGROUND

The increased availability of caffeinated drinks raises questions about the level of caffeine that is appropriate for children, as well as the benefits and risks associated with their consumption.

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, this systematic review evaluates evidence from randomised controlled trials investigating the effects of caffeine on cognition, behaviour, mood and exercise performance in children. Observational studies and expert panel guidelines are also discussed.

RESULTS

One hundred and nine studies were found, with 11 randomised controlled trials and 13 observational studies meeting the criteria. High caffeine intakes (e.g. >5 mg kg(-1) body weight day(-1)) were associated with an increased risk of anxiety and withdrawal symptoms. However, smaller amounts were not linked with such effects and may benefit cognitive function and sports performance based on adult studies. The evidence suggests that children and adolescents should limit daily caffeine consumption to 2.5 mg kg(-1) body weight day(-1), equating to one or two cups of tea or one small cup of coffee. Lower contributors of caffeine, such as tea, may be more appropriate for children because they contribute to daily fluid intakes and provide flavonoids. By contrast, caffeinated soft drinks may be less suitable options for children as a result of their acidity, higher caffeine content, presence of added sugar (in some cases) and absence of bioactive compounds.

CONCLUSIONS

More studies are needed to determine the intakes that represent a risk and whether there may be benefits for alertness and sports performance with moderate intakes of caffeine.