Associations between eating habits and mental health among adolescents in five nordic countries : a cross-sectional survey

This is a self-archived version of an original article. This version may differ from the original in pagination and typographic details. Author(s): Title: Year: Version: Copyright: Rights: Rights url: Please cite the original version: CC BY 4.0 https://creativecommons.org/licenses/by/4.0/ Associations between eating habits and mental health among adolescents in five nordic countries : a cross-sectional survey © The Author(s) 2024 Published version Fismen, Anne-Siri; Aarø, Leif Edvard; Thorsteinsson, Einar; Ojala, Kristiina; Samdal, Oddrun; Helleve, Arnfinn; Eriksson, Charli Fismen, A.-S., Aarø, L. E., Thorsteinsson, E., Ojala, K., Samdal, O., Helleve, A., & Eriksson, C. (2024). Associations between eating habits and mental health among adolescents in five nordic countries : a cross-sectional survey. BMC Public Health, 24, Article 2640. https://doi.org/10.1186/s12889-024-20084-w 2024 Fismenetal. BMC Public Health (2024) 24:2640 https://doi.org/10.1186/s12889-024-20084-w RESEARCH Open Access © The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. BMC Public Health Associations betweeneating habits andmental health amongadolescents infive nordic countries: across-sectional survey Anne‑Siri Fismen1*, Leif Edvard Aarø2,3, Einar Thorsteinsson4, Kristiina Ojala5, Oddrun Samdal3, Arnfinn Helleve2 and Charli Eriksson6 Abstract Background The role of eating habits in adolescent mental health has become a growing area of inter‑ est for researchers and health professionals. Recent studies suggest that healthy eating habits may play a role in the development and management of mental health. However, existing literature is largely based on clinical popu‑ lations, and comparisons are challenged by sociocultural differences and methodological issues. The aim of the pre‑ sent study was to use nationally representative data based on standardized procedures, to explore associations between adolescents eating habits and mental health, considering the importance of age, gender, socioeconomic factors, and country. Methods The study was based on data from Nordic adolescents (age 11, 13 and 15 years) who participated in the 2017/2018 Health Behavior in School‑aged Children (HBSC) study (n = 22384). General linear modelling and multigroup regression analysis were used to examine the relationship between food habits (intake of fruit, vegetables, sweets, soft drinks), meal habits (intake of breakfast and having family meals together), and mental health (life satisfaction and subjective health complaints). The analyses were weighted and adjusted for age, gender, socio‑ economic status, and country. Results Overall, healthier eating habits were associated with better mental health. The strongest associations were found between meal habits (breakfast consumption and having family meals together) and mental health. Gender and country differences were seen, with weaker associations found among Danish boys. Conclusion Eating habits should be considered when promoting mental health in the adolescent population. While gender differences and cross‑country variations exist, even minor enhancements in eating behaviors could yield meaningful benefits. Keywords Food habits, Meal habits, Adolescents, Mental health, Mental well‑being *Correspondence: Anne‑Siri Fismen Anne‑Siri.F[email protected] Full list of author information is available at the end of the article Page 2 of 12 Fismenetal. BMC Public Health (2024) 24:2640 Introduction Good mental health and well-being during adolescence are critical to ensuring healthy transitions to adulthood, with implications for overall well-being, growth and development, and social and educational outcomes [1]. In the Nordic countries, the prevalence of child and adolescent mental illness appears comparatively lower than in numerous other Western countries [2, 3]. Nonetheless, recent trend studies indicate an increase in adolescents’ self-reported mental health complaints, and that the increase is more pronounced in the Nordic countries compared to other regions [4, 5]. Furthermore, trends of decrease in adolescent life satisfaction have been reported in most of the Nordic countries [6]. The etiology of these changes is not clear but do most likely involve a complex interplay of factors at both individual and contextual levels [7]. Furthermore, they are accompanied by trends of low and even decreased fruit and vegetable intake [8], increased intake of ultra-processed food [9], and, in Denmark and Sweden, also by less regular meal frequency [10]. Thus, the relationship between eating habits and adolescent mental health and well-being has become a growing area of interest for researchers and health professionals. Additionally, adolescents themselves strongly emphasize the link between eating habits and mental health [11]. Accumulating evidence from observational and intervention studies in nutritional psychiatry and psychology highlights the importance of diet for mental health development (9–12). Potential pathways underpinning these associations include those of the gut-brain axis and the role of specific nutrients in supporting brain function and neurotransmitter activity, which may have a positive effect on the development and management of mental health [12]. In this context, diet is the greatest modulator of the immune system-microbiota crosstalk, and much interest, and new challenges, are arising in precision nutrition as a way towards treatment and prevention [13]. However, while the impact of individual nutrients on mental illness is essential from a clinical perspective (9–12), the link between whole foods and general eating habits, and self-reported mental health and well-being, has a greater relevance in the field of public health. This broader perspective aims to more effectively address health benefits associated with eating habits and overall dietary intake in the general population. Importantly, eating habits may be largely modifiable, unlike other mental health risk factors (e.g., genetics), and are therefore highly relevant in promotion and prevention. Increased intake of nutrient-dense foods such as fruits and vegetables has previously been linked to favorable impacts on mental health and well-being such as through higher levels of mental well-being [14]. However, the effect sizes were small and potentially mediated by socioeconomic status (SES) and other factors. A systematic review suggested that there might be an association between fruit and vegetable consumption and adolescents’ self-reported mental health and well-being [15]. Furthermore, consumption of sugar-sweetened beverages, fast food [16, 17], and other examples of ultra-processed food [18] are associated with symptoms of depression and anxiety, stress, and sleep dissatisfaction among children and adolescents. Beyond food habits, several studies link regular breakfast consumption and frequent family meals to adolescents’ mental health and well-being as well as to academic achievement [19–23]. Family routines like family meals are an essential part of family life and might offer consistency and a venue for checking in with family members. Family meals may thus act as contextual opportunities in which adolescents and their families can connect and strengthen their bonds [22]. As highlighted in the umbrella review by Snuggs etal. [24], sharing family meals may play a protective role in young people’s food habits and mental well-being, enhance the presence of family members, and foster a positive mealtime atmosphere. A meta-analysis suggested that skipping breakfast had somewhat an effect on increasing stress, psychological distress, and depression with mixed findings for anxiety [20]. Identifying determinants and pathways crucial for positive mental health among children and adolescents is underscored in the World Health Organization’s (WHO) mental health action plan [25]. However, the relationship between eating habits and mental health is complex, multifaceted, and not fully understood. Current evidence targeting both specific nutrients as well as whole foods and overall dietary patterns are largely based on clinical populations and comparisons are challenged by different conceptuality, sociocultural differences, and methodological issues. Studies based on nationally representative samples are scarce, and few studies allow for cross-country comparisons. Population-based studies are needed to explore this relationship and to inform public health interventions addressing adolescents’ mental health. Despite contextual similarities between the Nordic countries, cross-country differences are observed in e.g., adolescents’ food habits [26] and mental health [4, 5]. Cross-country comparisons can help identify the similarities and differences in associations between eating habits and mental health across different countries, which can provide insights into the underlying factors that contribute to these associations. Such research is the focus of an ongoing research collaboration on mental health among Nordic adolescents [27], represented by the authors behind this current study. Page 3 of 12 Fismenetal. BMC Public Health (2024) 24:2640 The Health Behavior in School-aged Children (HBSC) is a WHO collaborative cross-national study whose overall aim is to generate a greater understanding of health and health behavior and their context in the lives of young people [1]. These data have to a large extent been used to explore associations between mental health and a range of individual and contextual determinants [7]. However, as highlighted by Currie and Morgan [7], these data have not been used to investigate associations between mental health and eating habits in a crossnational sample. The aim of the present study was to use data from Nordic adolescents, aged 11, 13, and 15 years, participating in the 2018 HBSC study to explore associations between adolescents eating habits (food habits and meal habits) and mental health (health complaints and life satisfaction), considering the importance of age, gender, socioeconomic factors, and country. Methods The study was based on nationally representative data from adolescents living in Denmark, Finland, Iceland, Norway, and Sweden, participating in the 2017/2018 HBSC study. The sampling procedure followed the HBSC standardized protocol (28) with the objective of achieving at least 1500 participants for each age group, assuming a 95% confidence interval of +/- 3% around a proportion of 50% and a design factor of 1.2, based on analyses of existing HBSC data [28]. The sampling unit of the participants varied slightly between the countries. In Finland, Norway, and Sweden, the primary sampling unit was the school class. In Finland, the probability proportional to size sampling method (PPS) was applied in school selection and the number of pupils in the schools was used as the measure of size. Within sampled schools, one class was randomly selected to participate. In Norway, the number of pupils at each class-level the previous school year was used to estimate the number of classes. In Sweden, a nationally representative sample of schools within the grades 5, 7, and 9 were randomly selected. Then a single class was randomly selected from each school according to instructions from Statistics Sweden. In Denmark, the primary sampling unit was the school. All students in the relevant grades were invited to participate. In Iceland, all schools in the country were invited to participate in the data collection to achieve the needed sample size. The students completed the HBSC internationally standardized questionnaire at school after receiving instructions from their teacher (28). The administration of the questionnaire used computers in Denmark, Finland, and Norway, paper-and-pencil in Sweden, and in Iceland both methods. Oral and written information outlining the confidentiality of their responses was provided, and participation was confidential and voluntary. Response rates varied across the countries. Schools/classes that declined to participate, and students who were absent on the day the survey was completed were the two main sources of nonresponse and were not followed up. The HBSC Data Management Centre checked the quality of the data collected, performed appropriate cleaning of the data, and merged national data sets into a Nordic data file. Detailed information about the study is available at www. hbsc. org. Measures Self-reported health complaints and life satisfaction are understood as components of mental health [7]. These indicators are frequently used to measure adolescents’ self-reported mental health and well-being [1, 7]. In the present study, health complaints were measured by the HBSC Symptom Check List (HBSC-SCL); an eight item measure that may have both psychological and somatic origins [1]. Based on the HBSC Symptom Checklist (HBSC-SHC), the adolescents were asked how often they experienced the following symptoms over the past 6 months: headache, abdominal pain, backache, feeling low, irritability or in a bad mood, feeling nervous, sleeping difficulties, and dizziness. The five response categories were “About every day,” “More than once a week,” “About every week,” “About every month,” and “Rarely or never.” Consistent with standard procedures in HBSC (28), a recoded mean score was constructed (sum score divided by the number of items with valid data) and ranged from 1(Rarely or never any symptoms) to 5 (All eight symptoms about every day). The HBSC-SHC has adequate test–retest reliability and validity properties [29]. Cronbach’s alpha for the HBSC-SHC was 0.84. Life satisfaction is defined as “A cognitive global judgment of one’s life as a whole” [30]. Participants rated their life satisfaction using a single-item question referred to as the Cantril ladder [31]: “Here is a picture of a ladder. The top of the ladder ‘10’ is the best possible life for you and the bottom ‘0’ is the worst possible life for you. In general, where on the ladder do you feel you stand at the moment?” The Cantril ladder has shown good reliability and convergent validity among adolescents [32]. Eating habits was measured by food habits (fruit, vegetables, sweets, and sugar-sweetened soft drinks consumption) and meal habits (breakfast consumption and having family meals together). Food habits was measured by questions on frequency of intake: “How many times a week do you consume fruit/vegetables/sweets/sugarsweetened soft drinks?” The response categories were ‘Never’, ‘Less than once a week, ‘Once a week’, ‘Two to four times a week’, ‘Five to six times a week’, ‘Once a day’, and ‘More than once a day’. For the present study, the response categories were recoded into ‘Never’ = 0; ‘Less than once a week’ = 0.5; ‘Once a week’ = 1.0; ‘Two to four Page 4 of 12 Fismenetal. BMC Public Health (2024) 24:2640 times a week’ = 3.0; ‘Five to six times a week’ = 5.5; ‘Once a day’ = 7.0; ‘More than once a day’ = 10.0). The question, which is part of the HBSC food checklist, is a recognized as valid instrument in epidemiological studies ranking adolescents according to their usual food intake [33]. Meal habits was measured by questions on breakfast consumption and family meals. Breakfast consumption: “How often do you usually have breakfast (more than a glass of milk or fruit juice)? Please tick one box for weekdays and one box for weekends” The response categories were ‘I never have breakfast during the week’ (0), ‘One day’ (1), ‘Two days’ (2), ‘Three days’(3), ‘Four days’ (4) and ‘Five days’ (5) for schooldays; and ‘I never have breakfast during the weekend’ (0), ‘I usually have breakfast on only one day of the weekend (Saturday OR Sunday)’(1) and ‘I usually have breakfast on both weekend days (Saturday AND Sunday)’ (2). The responses were summed to a total range of days of eating breakfast (0–7 days a week). Family meals: “How often do you and your family usually have meals together?” The response categories were ‘Every day’, ‘Most days’, ‘About once a week’, ‘Less often’, ‘Never’. The responses were recoded and summed to a total range of family meals over a week: ‘Every day’ =7, ‘Most days’ = 5, ‘About once a week’ = 1, ‘Less often’ = 0.5’, ‘Never’ = 0.5. The item is considered a reliable measure to address family meals in a Nordic context [34]. Socioeconomic status was measured by the family affluence scale which comprises six items and is a measure of material affluence derived from the characteristics of the family’s household. In line with the HBSC recommendations [35], SES was categorized into the lowest (20%) middle (60%), and highest (20%) groups, based on the country’s FAS score distribution. Statistical analyses Data were weighted to compensate for over-sampling of Swedish-speaking adolescents in Finland. Data were also weighted to ensure equal representation across gender, age, and countries while preserving the total number of observations. After weighting of data, the number of observations in each subgroup defined by gender, age, and country was 738. The total number of observations before weighting was 22,384 (247 with information missing on gender). After weighting the total number of observations was 22,385, or 22,140 with those with missing on gender excluded. In all statistical analyses, adjustments were made for cluster effects. In Iceland, the school authorities in Reykjavik did not approve registering of schools or school classes. Therefore, all schools in Reykjavik were treated as belonging to one cluster (per age). Preliminary analysis (shown in Supplementary Table 1) indicated that some eating habits variables were moderately correlated; breakfast during weekdays and breakfast during weekends (r = .368), (fruit consumption and vegetable consumption (r = .550), and sweets consumption and soft drink consumption (r = .523). All other correlations were small, in the range of 0.040 to 0.151. Three summary scores, one for each pair of variables were therefore constructed and used in the multigroup analyses comparing mean scores across subgroups. To produce summary variables covering all eating variables combined, global indices for healthy eating, general linear modelling (GLM) was run with all seven eating variables as predictors and the health complaints sumscore and life satisfaction as outcomes. The predicted values were saved and recoded into deciles. A distinction could be made between meal habits (breakfast weekdays, breakfast weekends, family meals) and food habits (consumption of fruit, vegetables, sweets, soft drinks), and summary variables were constructed for (i) meal habits predicting health complaints, (ii) food habits predicting health complaints, (iii) meal habits predicting life satisfaction, and (iv) food habits predicting life satisfaction. These variables were not recoded into deciles but standardized and used in a series of regression models conducted with Mplus. The score for (i) meal habits (predicting health complaints) and the score for food habits (ii) (predicting health complaints) were used in a multigroup regression model with health complaints as the dependent variable and with adjustment for age. Four groups were defined (a) boys from all countries except Denmark, (b) boys from Denmark, (c) girls from all countries except Denmark, and (d) girls from Denmark. The decision to distinguish between Danish boys and girls, and boys and girls from the other Nordic countries, was made after a series of GLM analyses in SPSS Complex which confirmed that such a distinction was required. Similar analyses were performed in multigroup regression model including iii) meal habits (predicting life satisfaction), and iv) food habits (predicting life satisfaction). Most of the statistical analyses were carried out with the GLM procedure in SPSS Complex. Complex allows for simultaneous weighting of data and adjustments for cluster effects. Some regression models as well as all multigroup testing of these models were done in Mplus with the MLR estimator, with weighting and adjustments for cluster effects. Results Table 1 shows mean score (M) and standard deviation (SD) on mental health and eating habits by gender. Supplementary Table1 shows correlations between the items. Page 5 of 12 Fismenetal. BMC Public Health (2024) 24:2640 The GLM analysis indicated that mean scores on mental health and eating habits were associated with gender, age, SES, and country (Table2). Girls reported lower life satisfaction and more health complaints, higher fruit and vegetable consumption, lower soft drink consumption, less frequent breakfast during weekdays, and less frequent family meals than did boys. Older, compared to younger, adolescents reported lower life satisfaction and more health complaints, lower fruit consumption, higher sweets and soft drink consumption, less frequent breakfast consumption, and less frequent family meals. Vegetable consumption was less strongly and less consistently associated with age. Higher SES was associated with lower levels of health complaints and higher life satisfaction, as well as higher fruit and vegetable consumption, lower soft drink consumption, and more frequent meals. Higher levels of health complaints, as well as lower scores on life satisfaction, were seen in the Swedish sample. More frequent vegetable consumption, breakfast consumption, and family meals were seen in the Danish sample, while higher fruit consumption as well as lower sweets and soft drink consumption were seen in the Icelandic sample. As shown in Table3, higher fruit consumption, lower sweets consumption, as well as more frequent breakfast consumption (weekdays and weekends), and family meals were associated with lower levels of health complaints and higher life satisfaction. Lower soft drink consumption was associated with lower levels of health complaints. No significant associations were found between soft drink consumption and life satisfaction, nor between vegetable consumption and any of the two mental health measures. The associations were small, with the largest between breakfast consumption on weekdays and health complaints (r = − .124, p < .001) and family meals and life satisfaction (r = − .121, p < .001). Figure1a and b illustrates a close to linear relationship between healthy eating habits (predicted values recoded into decentiles) and health complaints and life satisfaction (standardized), and show that the healthier eating habits, the lower score on health complaints and higher life satisfaction. The association was close to linear across the last seven categories, but slightly steeper over the first three (less healthy eating habits). The difference between the top and bottom scores were 1.05 (health complaints) and 1.09 (life satisfaction). Given that the dependent variable was standardized, this value can be interpreted as a z-value. This means that the difference between the two extreme categories is large. When adjusting for demographic predictors (see Fig.2), the difference between the extreme groups on the eating habits scale was marginally smaller for health complaints (0.95) and life satisfaction (1.05). As shown in Fig.2, the multigroup regression model indicated that healthy food habits were negatively associated with health complaints, and there were no significant differences in the strength of this association across subgroups defined by gender and country (Denmark versus all the other Nordic countries) (r = − .128). Meal habits, compared to food habits, was generally more strongly associated with health complaints, but there was considerable variation across subgroups. Absolute association values were stronger among girls than among boys, and less strong in Denmark compared to the other countries. Table 1 Mental health and eating habits by gender Boys Girls n M SD M SD unweighted Mental health Health complaints (1–5) 1.95 0.75 2.32 0.88 21 713 Life satisfaction (0–10) 7.88 1.75 7.44 1.92 21 780 Food habits Fruit consumption (0–10) 4.43 3.15 5.05 3.11 21 794 Vegetable consumption (0–10) 4.87 3.09 5.54 3.02 21 689 Fruit and vegetable consumption combined (0–10) 4.65 2.75 5.30 2.69 21 809 Sweets consumption (0–10) 2.20 2.03 2.25 1.92 21 684 Soft drinks consumption (0–10) 2.22 2.31 1.57 1.93 21 694 Sweets and soft drinks consumption combined (0–10) 2.21 1.92 1.91 1.66 21 705 Meal habits Breakfast weekdays (0–5) 4.06 1.68 3.86 1.80 21 873 Breakfast weekends (0–2) 1.72 0.60 1.74 0.57 21 728 Breakfast weekdays and weekends combined (0–7) 5.78 1.97 5.60 2.07 21 624 Family meals (0–7) 5.12 2.11 4.88 2.12 21 750 Page 6 of 12 Fismenetal. BMC Public Health (2024) 24:2640 Table 2 Mean score on mental health and eating habits by gender, grade, SES, and country p-values adjusted for cluster effect Health complaints Life satisfaction Fruit consumption Vegetable consumption Sweets consumption Soft drink consumption Breakfast weekdays Breakfast weekends Family meals Measure M p M p M p M p M p M p M p M p M p Gender Boys 1.96 < 0.001 7.83 < 0.001 4.47 < 0.001 4.83 < 0.001 2.20 0.097 2.25 < 0.001 3.98 < 0.001 1.71 0.020 5.07 < 0.001 Girls 2.32 7.40 5.10 5.50 2.25 1.60 3.78 1.73 4.83 Age 11 years 2.00 < 0.001 7.99 < 0.001 5.15 < 0.001 5.26 0.015 1.96 < 0.001 1.68 < 0.001 4.19 < 0.001 1.79 < 0.001 5.25 < 0.001 13 years 2.15 7.53 4.67 5.05 2.30 1.96 3.88 1.70 5.01 15 years 2.28 7.32 4.54 5.19 2.43 2.13 3.57 1.65 4.59 SES Low 2.19 < 0.001 7.37 < 0.001 4.40 < 0.001 4.70 < 0.001 2.25 0.745 2.04 < 0.001 3.68 < 0.001 1.67 < 0.001 4.76 < 0.001 Middle 2.12 7.68 4.70 5.21 2.22 1.87 4.02 1.74 5.07 High 2.11 7.96 5.23 5.78 2.20 1.80 4.13 1.77 5.09 Country Denmark 1.99 < 0.001 7.60 < 0.001 5.14 < 0.001 5.75 < 0.001 2.45 < 0.001 2.09 < 0.001 3.89 < 0.001 1.79 < 0.001 5.36 < 0.001 Finland 2.22 7.79 4.25 4.67 2.08 1.88 3.87 1.71 4.06 Iceland 2.20 7.54 5.36 4.70 1.85 1.42 3.78 1.59 5.32 Norway 1.99 7.71 4.86 5.10 2.31 2.20 3.92 1.77 5.10 Sweden 2.30 7.44 4.33 5.61 2.45 2.03 3.93 1.73 4.90 Page 7 of 12 Fismenetal. BMC Public Health (2024) 24:2640 As shown in Fig.3, healthy food habits were positively associated with life satisfaction and there were no noticeable differences across countries (r = .121). Healthy meal habits, compared to food habits, was more strongly associated with life satisfaction except for Danish boys, but there was considerable variation across subgroups. Absolute associations were higher among girls than among boys and lower in Denmark compared to the other countries. Discussion The present study suggests that there may be limited associations between eating habits and mental health in Nordic adolescents, with gender differences and cross-country variations observed in the associations between meal habits and health complaints and life satisfaction. The association between fruit and vegetable consumption and mental health may be elucidated in the context of recent studies, which indicate that a higher Table 3 Health complaints and life satisfaction by eating habits, adjusted for gender, age, country, SES 1 R2 = 0.07 2 R2 = 0.131 Eating habits times per week Health complaints1Life satisfaction2 r p r p Fruit consumption − 0.044 < 0.001 0.108 < 0.001 Vegetable consumption 0.000 0.997 0.016 0.084 Sweets consumption 0.073 < 0.001 − 0.035 0.001 Soft drink consumption 0.072 < 0.001 − 0.016 0.072 Breakfast weekdays − 0.124 < 0.001 0.106 < 0.001 Breakfast weekends − 0.102 < 0.001 0.109 < 0.001 Family meals − 0.100 < 0.001 0.121 < 0.001 Fig. 1 a and b. Health complaints score and life satisfaction score by healthy eating (predicted values in deciles) Fig. 2 Health complaints by eating habits (NFULL MODEL = 22,384) adjusted for age and SES Page 8 of 12 Fismenetal. BMC Public Health (2024) 24:2640 intake of these foods may be associated with increased life satisfaction [14], reduced psychological distress [15] and other favorable outcomes of mental health in children and adolescents [15, 36] Furthermore, there was a weak inverse relationship between reduced sugar consumption and improved mental health in the present study, supporting results from previous studies in which it was concluded that high-calorie, low-nutrient value unhealthy foods are associated with increased odds of psychological distress in children and adolescents [37] and higher levels of stress and depressive symptoms [17]. In contrast, a systematic review suggested that chocolate consumption may lead to lower levels of depressive and anxiety symptoms in the short term [38]. This may be attributed to chocolate’s content of (poly) phenolic compounds and its positive impact on mood, depression, and other mental health outcomes [39]. The present study suggests that having family meals together may be associated with reduced health complaints and increased life satisfaction, which is in line with previous studies [20, 24]. Furthermore, also in line with previous research, girls, older adolescents, and adolescents living in families with lower SES, reported higher levels of health complaints and lower life satisfaction [40], while boys, younger adolescents, and adolescents living in families with higher SES reported more favorable food habits [1]. The role ofeating habits inadolescent mental health The findings of healthy eating habits as a predictor of better mental health may be explained by the hypothesis that food items high in essential nutrients are crucial for proper brain functioning and development [12]. This importance of essential nutrients extends to also explain the observed link between meal habits and mental health. Breakfast consumption and family meals are proposed to offer nutritional advantages, as regular breakfast consumption and sharing meals are associated with favorable dietary patterns in children and adolescents, including the consumption of fruits, vegetables, and various nutrients [19, 41, 42]. This perspective may explain the observed correlations between meal habits and food habits. However, while the present study indicates a consistent association between food habits and mental health across genders and countries, both gender and country differences emerged in the relationship between meal habits and mental health. This may indicate that food habits and meal habits involve different mechanisms. Whereas the consistent relationship between food habits and mental health leans towards an explication through essential nutrients and biochemical mechanisms [12], the importance of meal habits is more likely to be explained by sociocultural processes. Family meals can provide a context for parental support, parental modeling, and parental communication [24], serving as a platform to address various aspects of adolescents’ lives and develop coping strategies for daily challenges. Parental communication is previously suggested to positively impact children’s health [43] and to mediate the relationship between family meals and mental health [44]. This may explain the observed association between meal habits and health complaints and life satisfaction. However, it should be noted that family structure may act as a confounder in this relationship, as adolescents living in single-parent households may have less favorable food habits [45] and poorer mental health [46]. The observed associations between eating habits and mental health were statistically significant but small. Fig. 3 Life satisfaction by eating habits (NFULL MODEL = 22,384) adjusted for age and SES