A prospective investigation of dietary patterns and internalizing and externalizing mental health problems in adolescents

The association between junk foods consumption and attention deficit hyperactivity disorder in children and adolescents: a systematic review and meta-analysis of observational studies

The adverse effects of junk foods on the risk of attention deficit hyperactivity disorder (ADHD) symptoms were reported in several studies. In this meta-analysis, the association between junk food consumption and the risk of ADHD was investigated in children and adolescents. A comprehensive systematic search was conducted to find all relevant literature via four databases, including PubMed, Web of Science, Scopus, and Google scholar, up to September 2022. Two independent authors screened all documents based on inclusion criteria. The overall effect sizes and related 95% confidence interval (CI) were pooled with the random effect approach. Subgroup analysis was done to measure potential sources of heterogeneity between studies. The quality of the included studies was evaluated with The Newcastle-Ottawa scale (NOS). Nine observational studies with 58,296 children /adolescents were eligible to be include in the meta-analysis. According to the random effect model, there was a positive relation between the consumption of junk foods and ADHD symptoms (odds ratio (OR): 1.24, 95%CI 1.15-1.34, P < 0.001, I2: 37.4%, P = 0.085). A similar significant positive association was shown in the subgroups analysis by different junk foods (sweetened beverages/soft drinks, sweets/candies, and other types of junk foods). This meta-analysis finding demonstrated that consuming junk foods, especially sweetened beverages/soft drinks, and sweets/candies is associated with ADHD symptoms.

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.

PROTOCOL: The efficacy of nutritional interventions in reducing childhood/youth aggressive and antisocial behavior: A systematic review and meta-analysis

This is a protocol for a Campbell systematic review of intervention effectiveness. The goal of this systematic review is to answer the following questions based on the available empirical evidence: Are there nutritional interventions (dietary manipulation, fortification or supplementation) that can reduce excessive aggression towards others in children/youth? If yes, how strong is their effect and is there a difference among the three intervention types? Are there nutritional interventions that can reduce antisocial behaviors in children/youth? If yes, how strong is their effect and is there a difference among the intervention types? Are there nutritional interventions that can reduce violent offending in children/youth? If yes, how strong is their effect and is there a difference among the intervention types? Are there nutritional interventions that can reduce non-violent offending in children/youth? If yes, how strong is their effect and is there a difference among the intervention types? What implementation barriers and solutions to these exist in relation to the above nutritional interventions in children/youth?

Association Between Dietary Patterns and Bullying Among Adolescents in Sao Paulo-Brazil

Previous studies have assessed the association between food consumption and bullying perpetration, but most of them have not broadly assessed food consumption, neither the distinction between forms of bullying. The aim of the study was to evaluate the association between dietary patterns with bullying roles and its different types of bullying perpetration among adolescents. Data on a representative sample of ninth-grade students (N = 2,163; mean age = 14.8 years) taken from Sao Paulo Project for the social development of children and adolescents (SP-PROSO) were used. The independent variables were healthy and unhealthy dietary patterns obtained by exploratory factor analysis. The dependent variables were bullying role (victim-only, bully-only, bully-victim) and bullying perpetration (any type, social exclusion, psychological/verbal aggression, physical aggression, property destruction, sexual harassment). Multinomial and logistic regression models were performed for the total sample and stratified by sex (only for association with sexual harassment), adjusting for covariates. Adolescents who engaged in a healthy dietary pattern were less likely to be bullies (RR 0.67 [0.49, 0.92]), while adolescents with an unhealthy dietary pattern were more likely to be bully-victims (RR 1.29 [1.12, 1.48]). Unhealthy dietary pattern was associated with any type of bullying perpetration (OR 1.24 [1.12, 1.38]), mainly with sexual harassment and physical aggression. Boys who had an unhealthy dietary pattern were more likely to sexually harass another adolescent (OR 2.10 [1.20, 3.66]). In conclusion, adolescents who had a healthy dietary pattern were less likely to perpetrate bullying. Unhealthy dietary pattern was associated with bullying perpetration, especially with sexual harassment by boys.

Adolescent endocrine disrupting chemical exposure and academic achievement

BACKGROUND

Epidemiologic studies support associations of exposure to endocrine disrupting chemicals (EDCs), such as some phthalates, phenols, and parabens with a wide range of cognitive and behavioral traits. While many of these traits are associated with academic achievement, the relationship of EDC exposure specifically with academic achievement in adolescence has not yet been studied.

OBJECTIVE

We assessed the association of urinary biomarker concentrations of EDCs with academic achievement in adolescents as well as the potential for psychosocial factors to modify associations.

METHODS

We quantified urinary concentrations of select EDCs in 205 adolescent participants from the New Bedford Cohort (NBC), a prospective birth cohort of children born to mothers residing near the New Bedford Harbor Superfund site in Massachusetts, and estimated associations between EDCs and adolescent academic achievement assessed with the Wide Range Achievement Test (WRAT). Measures of socioeconomic status and the home environment were used to estimate psychosocial stress.

RESULTS

Urinary concentrations of antiandrogenic phthalates were inversely associated with Math Computation scores. For example, each doubling of the concentration of antiandrogenic phthalate metabolites in urine was associated with a 1.94 point decrease (95% CI: 3.84, -0.05) in Math Computation scores, indicating poorer performance. For the most part, associations were stronger in adolescents with more, as compared to less, social disadvantage, but most of these differences did not achieve statistical significance.

CONCLUSION

Our findings support the potential for adolescents' exposure to antiandrogenic phthalates to correlate with poorer academic achievement in math, particularly among participants with greater psychosocial stress.

Dietary patterns and internalizing symptoms in children and adolescents: A meta-analysis

CONTEXT

Studies of child and adolescent internalizing symptoms and dietary pattern have produced mixed results.

OBJECTIVES

To quantify the association between dietary patterns and internalizing symptoms, including depression, in children and adolescents.

DATA SOURCES

Embase, PsycINFO, MEDLINE, Web of Science and Cochrane up to March 2021.

STUDY SELECTION

Observational studies and randomized controlled trials with mean age ⩽ 18 years, reporting associations between diet patterns and internalizing symptoms.

DATA EXTRACTION

Mean effect sizes and 95% confidence intervals were determined under a random-effects model.

RESULTS

Twenty-six studies were cross-sectional, 12 were prospective, and 1 used a case-control design. The total number of participants enrolled ranged from 73,726 to 116,546. Healthy dietary patterns were negatively associated with internalizing (r = -0.07, p < 0.001, 95% confidence interval [-0.12, 0.06]) and depressive symptoms (r = -0.10, p < 0.001, 95% confidence interval [-0.18, -0.08]). Effect sizes were larger for studies of healthy dietary patterns and internalizing and depressive symptoms using self-report versus parent-report measures, as well as in cross-sectional studies of healthy dietary patterns and depression compared to prospective studies. Unhealthy dietary patterns were positively associated with internalizing (r = 0.09, p < 0.001, 95% confidence interval [0.06, 0.14]) and depressive symptoms (r = 0.10, p < 0.01, 95% CI [0.05, 0.17]). Larger effect sizes were observed for studies of unhealthy dietary patterns and internalizing and depressive symptoms using self-report versus parent-report measures.

LIMITATIONS

A lack of studies including clinical samples and/or physician diagnosis, and a paucity of studies in which anxiety symptoms were the primary mental health outcome.

CONCLUSION

Greater depression and internalizing symptoms are associated with greater unhealthy dietary patterns and with lower healthy dietary intake among children and adolescents.

Dietary patterns in middle childhood and behavior problems in adolescence

BACKGROUND/OBJECTIVES

Adherence to a "Western" style dietary pattern has been related to behavior problems in children in high-income countries; however, dietary patterns may differ in countries undergoing the nutrition transition. Associations of dietary patterns with behavior problems in a Latin American context have not been evaluated.

SUBJECTS/METHODS

Mothers of 385 children 5 to 12 y old completed a food frequency questionnaire (FFQ) on the children's usual intake at enrollment into a cohort study. Four dietary patterns were identified through principal component analysis of the FFQ: animal protein, snacking, cheaper protein, and traditional/starch. After a median 6 y follow-up, adolescents reported behavior problems via the Youth Self Report, a standardized questionnaire. We compared the continuous distributions of externalizing and internalizing behavior problems and their subscales across quartiles of adherence to the four dietary patterns using multivariable linear regression.

RESULTS

Boys in the highest quartile of adherence to the animal protein pattern in middle childhood had an adjusted 5.5 units lower (95% CI -9.5, -1.5) mean total externalizing problems score compared with boys in the lowest quartile (P trend = 0.008). Adherence to the animal protein pattern was also inversely related to the aggressive behavior externalizing subscale in a dose-response manner among boys (P trend = 0.009). There were no associations between adherence to other dietary patterns and externalizing problems in boys or girls. There were no associations with internalizing problems.

CONCLUSION

Adherence to an animal protein dietary pattern in middle childhood was associated with less externalizing behavior problems in adolescent boys.

Association of Exposure to Endocrine-Disrupting Chemicals During Adolescence With Attention-Deficit/Hyperactivity Disorder-Related Behaviors

IMPORTANCE

Attention-deficit/hyperactivity disorder (ADHD) is the most common childhood neurobehavioral disorder. Studies suggest that prenatal and early childhood exposure to endocrine-disrupting chemicals may be associated with ADHD, but the association during adolescence has not been studied to date.

OBJECTIVE

To evaluate the association between exposure to select endocrine-disrupting chemicals during adolescence and ADHD-related behaviors.

DESIGN, SETTING, AND PARTICIPANTS

For this cross-sectional analysis, data were collected from 205 adolescents in the New Bedford Cohort, an ongoing prospective birth cohort, between June 18, 2011, and June 10, 2014. The adolescents provided spot urine samples and underwent neurodevelopmental testing. Statistical analyses performed from January 15 to December 31, 2019, used a repeated-measures analysis with multivariate modified Poisson models to estimate the adjusted relative risk of ADHD-related behaviors associated with exposure to endocrine-disrupting chemicals.

EXPOSURES

Urinary biomarker concentrations of endocrine-disrupting chemicals or their metabolites, including phthalates, parabens, phenols, and triclocarban, were quantified. Summary exposure measures were created, combining biomarker concentrations of chemicals with a shared mechanism of action, exposure pathway, or chemical class.

MAIN OUTCOMES AND MEASURES

Behaviors related to ADHD were assessed with up to 14 indices from self-, parent-, and teacher-completed behavioral checklists using validated and standardized instruments; specifically, the Conners Attention Deficit Scale and the Behavior Assessment System for Children, Second Edition. Scores on each index were dichotomized to identify those with evidence of a significant behavioral problem, defined by each scale's interpretive guidelines.

RESULTS

Among the 205 participants, the mean (SD) age at assessment was 15.3 (0.7) years, with 112 girls (55%) and 124 non-Hispanic White participants (61%). The median urine concentrations were 0.45 μmol/L of Σantiandrogenic phthalates, 0.13 μmol/L of ΣDEHP metabolites, 0.49 μmol/L of Σpersonal care product phthalates, 0.35 μmol/L of Σparabens, 0.02 μmol/L of Σbisphenols, and 0.02 μmol/L of Σdichlorophenols. A total of 82 (40%) had scores consistent with a significant behavioral problem, whereas 39 (19%) had an ADHD diagnosis. Each 2-fold increase in the sum of antiandrogenic phthalate concentrations was associated with a 1.34 (95% CI, 1.00-1.79) increase in the risk of significant ADHD-related behavior problems, whereas a 2-fold increase in the sum of dichlorophenols was associated with a 1.15 (95% CI, 1.01-1.32) increased risk. These associations tended to be stronger in male participants, but comparisons of sex-specific differences were imprecise.

CONCLUSIONS AND RELEVANCE

Endocrine-disrupting chemicals are used in a wide variety of consumer products resulting in ubiquitous exposure. The study findings suggest that exposure to some of these chemicals, particularly certain phthalates, during adolescence may be associated with behaviors characteristic of ADHD.

Sodium and potassium excretion predict increased depression in urban adolescents

This study examined the prospective role of urinary sodium and potassium excretion in depressive symptoms among urban, low-income adolescents, and whether these relationships vary by gender. A total of 84 urban adolescents (mean age 13.36 years; 50% male; 95% African American) self-reported on their depressive symptoms at baseline and 1.5 years later. At baseline, the youth also completed a 12-h (overnight) urine collection at home which was used to measure sodium and potassium excretion. After adjusting for baseline depressive symptoms, age, BMI percentile, and pubertal development, greater sodium excretion and lower potassium excretion predicted more severe depressive symptoms at follow-up, with no significant gender differences. The results suggest that consumption of foods high in sodium and low in potassium contributes to the development of depressive symptoms in early adolescence, and that diet is a modifiable risk factor for adolescent depression. Interventions focusing on diet may improve mental health in urban adolescents.

Fast food consumption and suicide attempts among adolescents aged 12-15 years from 32 countries

BACKGROUND

We examined the fast food consumption-suicide attempt relationship among 105,061 adolescents aged 12-15 years from 32 countries.

METHODS

This study was based on cross-sectional data from the Global School-based Student Health Survey (GSHS), and included 4 low-income, 13 lower middle-income, 9 upper middle-income, and 6 high-income countries. Data on past 7-day fast food consumption and 12-month suicide attempts were collected. The association between fast food consumption and suicide attempts was investigated with multivariable logistic regression and meta-analysis while adjusting for sex, age, food insecurity (proxy of socioeconomic status), alcohol consumption, smoking, physical activity, obesity, carbonated soft drink consumption, and fruit and vegetable consumption.

RESULTS

Overall, the prevalence of fast food consumption was high (53.5%) and the proportion of suicide attempts was higher among consumers of fast food compared to non-consumers (11.8% vs. 8.3%). Of the 32 countries included in the study, a positive association between fast food consumption and suicide attempts was found in 26 countries although this was not statistically significant in all countries. The pooled OR (95% CI) based on a meta-analysis was 1.31 (1.17-1.46).

LIMITATIONS

Since this was a cross-sectional study, it is not possible to draw any conclusions about causality or temporality in the associations assessed.

CONCLUSIONS

Fast food consumption is positively associated with suicide attempts in adolescents. Further research of longitudinal design is needed to confirm/refute our findings and explore the potential underlying mechanisms.

The relationship between inflammatory dietary pattern in childhood and depression in early adulthood

BACKGROUND

Inflammation may be a hidden process in the relationship between dietary intake and depression, but no study has evaluated the role of diet and inflammation jointly in explaining depression risk in early life. The current study aims to investigate the relationship between inflammatory dietary pattern (IDP) in childhood and depression in early adulthood.

METHODS

This study used data prospectively collected over 10 years from the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort (n ​= ​6939) free from depression at baseline (age 8.5 years). An IDP score was empirically derived via reduced rank regression and stepwise linear regression based on dietary intake data from the food frequency questionnaire at 8.5 years and levels of inflammatory biomarkers, C-reactive protein and interleukin-6, at 9.5 years. At age 18 years, depression cases were identified via the International Statistical Classification of Diseases, 10th Revision (ICD-10) diagnosis and the Clinical Interview Schedule-Revised (CIS-R) depression score. Logistic regression models were constructed to examine the relationship between the IDP score and risk of depression adjusted for potential confounders. Analyses stratified by weight status were also conducted. Multiple imputations were utilized to minimize bias due to loss-to-follow-up.

RESULTS

Participants in the highest tertile of IDP score had 1.34 times odds to develop depression compared to those in the lowest tertile (95% CI, 1.08-1.66; P-trend<0.01), after dietary misreporting status and energy intake were adjusted. After all covariates were adjusted, the relationship between IDP tertiles and depression was attenuated (highest tertile vs. lowest tertile: OR ​= ​1.21; 95% CI, 0.96-1.51); in addition, the relationship was marginally significant among participants who were not overweight or obese (p ​< ​0.10) but not significant among participants who were overweight or obese.

CONCLUSIONS

Higher IDP in childhood seems to be associated with higher depression risk in early adulthood. The study provides preliminary evidence that chronic inflammation may underlie the relationship between diet and depression even for children, especially those who are not overweight or obese.

Lifestyle, appearance satisfaction and depressive symptoms in 13-16 years old Norwegian adolescents - A cross-sectional study

Purpose: To examine gender-specific associations between multiple lifestyle-related risk factors, appearance satisfaction and depressive symptoms in a sample of Norwegian adolescents (13-16 years of age), and to study the role of appearance satisfaction as a possible confounder in the associations between lifestyle and depressive symptoms. Materials and methods: Data were obtained from Ungdata, a cross-sectional national survey of adolescents in Norway. In total 4379 subjects were included in the study. We constructed a lifestyle risk index and used multiple logistic regressions to examine the associations between lifestyle-related risk factors, appearance satisfaction, and depressive symptoms. Results: High screen time and use of alcohol were significantly associated with depressive symptoms among girls, while high screen time, tobacco and cannabis use were significantly associated with depressive symptoms among boys. An additive relationship was observed between the lifestyle risk index scores and the likelihood of depressive symptoms for both genders, the relationship being strongest among boys. Low appearance satisfaction was strongly associated with depressive symptoms, especially among boys, and identified as an important confounder in the associations between lifestyle and depressive symptoms, particularly among girls. Conclusions: High screen time was the most prevalent lifestyle risk behavior independently associated with depressive symptoms. Multiple lifestyle changes and improvement of appearance satisfaction should be included in measures targeting adolescents for the prevention and treatment of depressive symptoms. Future studies should elaborate on the gender differences in other adolescent age groups. Appearance satisfaction should be acknowledged as an important confounder in future studies of lifestyle and depressive symptoms.

Endocrine disrupting chemical exposure and maladaptive behavior during adolescence

BACKGROUND

Studies suggest that exposure to endocrine disrupting chemicals (EDCs), including phthalates, phenols, and parabens may influence childhood behavior, but the relationship during adolescence has not been assessed.

OBJECTIVE

We investigated the association between urinary biomarker concentrations of potential EDCs, including some phthalate and bisphenol A replacement chemicals, and behavior in adolescents.

METHODS

Participants were from the New Bedford Cohort (NBC), a prospective birth cohort of residents near the New Bedford Harbor Superfund site in Massachusetts. We measured urinary concentrations of 16 phthalate metabolites or replacements, 8 phenols, and 4 parabens in 205 NBC adolescents and estimated associations between select EDCs and adolescent behavior assessed with the Behavior Assessment System for Children, Second Edition -Teacher Rating Scale (BASC-2). Of note, up to 32 of the 205 in our assessment had missing outcome information imputed.

RESULTS

Increased urinary concentrations of the sum of 11 antiandrogenic phthalate metabolites were associated with an increase in maladaptive behaviors (Externalizing Behavior, Behavioral Symptoms Index, and Developmental Social Disorders or DSD), and a decrease in Adaptive Skills. For example, a doubling of urinary concentrations of antiandrogenic phthalate metabolites was associated with an increased risk of Externalizing Behavior (RR=1.04; 95% CI: 1.01-1.08). While associations were generally stronger in males, sex differences were not statistically significant. Urine concentrations of phenols and parabens were not associated with adverse behavior.

CONCLUSION

Our findings support the importance of exposure to antiandrogenic phthalates during adolescence as a potential correlate of maladaptive behaviors including Externalizing Behavior, DSD behaviors, and decrements in Adaptive Skills.

Promoting Mental Health and Wellness in Youth Through Physical Activity, Nutrition, and Sleep

The medical benefits to youth conferred by physical activity, balanced nutrition, and quality sleep have been increasingly encouraged by medical and mental health providers. Emerging evidence continues to reveal benefits for youth mental health and well-being, including for youth with psychiatric disorders. This evidence seems multifactorial through both neurobiological and psychosocial systems, with common mechanisms present between physical activity, nutrition, and sleep. This article reviews the benefits of optimizing physical activity, nutrition, and sleep; how to assess these lifestyle domains with patients and their parents; and appropriate interventions to optimize well-being in youth.

The Role of Dietary Patterns in Mood Disorders: Prospective Research in Youth Populations

Childhood mood disorders, including depression and bipolar spectrum disorders, represent serious public health concerns and often extend into adulthood. Due to increasing rates of a mood disorder diagnosis, and its accompanying risk of suicide, identification and management in childhood and adolescence is critical. Yet, fully effective and safe treatment options are lacking for child-onset mood disorders. Research investigating relationships between nutrition and psychiatry is a plausible avenue to improve prevention and treatment options. Epidemiological and observational evidence exists to support a protective effect of the Mediterranean diet in mood disorder prevalence and future diagnosis. To date, the majority of research has been conducted in adult populations. Future research is needed to examine if similar dietary relationships exist within a youth mood disorder population. Additionally, increased homogeneity in assessment methods of mood disorder symptoms and dietary patterns is needed; specifically, to determine more collective conclusions via meta-analyses. Results from youth studies could be used to formulate future randomized controlled trials, health promotion programs or clinical interventions, via diet or supplement interventions, for alternative mood disorder treatment or prevention purposes.

Diet quality and bullying among a cross-national sample of youth

Bullying perpetration and victimization have been linked to a number of high-risk health behaviors, including involvement in sedentary activities and sleep deprivation. Even so, the link between diet quality and bullying is generally overlooked. The present study examines the associations between diet quality, bully perpetration, and bully victimization in a cross-national sample of adolescents. Data come from the Health Behaviors of School Children (HBSC) survey, 2005/2006 (N=142,828-143,425). Youths from 41 countries/regions in North America and Europe reported features of their social context, various health behaviors, and their involvement in bullying. Approximately 11% of youth in the sample bully other youths at least 2-3 times a month, whereas 13% of youth are bullied by other youths at least 2-3 times a month. Logistic regression analyses revealed that youths with low quality diets incurred a 123% increase in the odds of attaining bully status, relative to youths with high quality diets. No such association was detected between diet quality and victim status. Results also suggest that the association between low diet quality and bully perpetration is significantly more pronounced in very developed nations (relative to developed nations). Dietary behaviors may be an important point of intervention in the effort to minimize the prevalence of bullying among youths, particularly in very developed nations. Scholars should seek to build upon the current study by exploring the mechanisms (e.g., low self-control) that might explain the association between diet quality and bullying.

The effect of school meals with fatty fish on adolescents' self-reported symptoms for mental health: FINS-TEENS - a randomized controlled intervention trial

There is a growing body of evidence linking fish consumption and n-3 LCPUFAs to mental health. Still, the results from randomized trials with n-3 LCPUFAs show conflicting results, and it is possible that the combined effect of several nutrients in fish may explain the observed associations. To aim of the present study was to investigate if school meals with fatty fish three times per week for 12 weeks could alter mental health in a sample of typically developing adolescents. In the Fish Intervention Studies-TEENS (FINS-TEENS), adolescents from eight secondary schools (n=425) in Norway, were randomized to receive school meals with fatty fish, meat or n-3 LCPUFA supplements. Mental health was assessed with the Strengths and Difficulties Questionnaire (SDQ) and the differences between the groups were assessed with linear mixed effect models, unadjusted and adjusted for baseline and dietary compliance. The results showed no effects of school meals with fatty fish compared to similar meals with meat or n-3 LCPUFAs on the adolescents' self-reported symptom scores for mental health. Among adolescents scoring above the SDQ cut-offs (high-scorers), the fish- improved less than the meat group in the self-reported symptom scores for total difficulties- and emotional problems. However, the findings should be regarded as preliminary, as the analyses for the high-scorer group were underpowered. In conclusion, serving school meals with fatty fish did not alter mental health in a typically developing sample of adolescents. It is possible that serving healthy school meals with meat is more beneficial than similar meals with fatty fish in adolescents scoring high on mental health problems. However, the results should be seen as preliminary, as the dietary compliance in the fish group was low and the analyses in the high score group underpowered. Thus, further studies should investigate the associations between fish consumption and adolescents' mental health.