School-based interventions offer a promising setting to promote healthier nutritional behaviours (NB) such as physical activity (PA), sedentary behaviour (SB) and eating behaviour, while addressing weight social inequalities. NB changes may occur before measurable effects on weight, which can take longer to emerge. This study evaluated the overall effectiveness of the school-based Promotion de l’ALIMentation et de l’Activité Physique – INEgalités de Santé (PRALIMAP-INÈS) trial on weight and NB social inequalities reduction among adolescents with overweight or obesity. Adolescents were divided into two intervention groups according to their socio-economic status (socially advantaged and socially less advantaged). NB were self-reported by adolescents. Outcomes were BMI z-score (BMIz), fruit and vegetables (FV) consumption, sweetened products and beverages (SPB) consumption, vigorous/moderate PA, walking and SB. Overall effectiveness was estimated using generalised pairwise comparisons, estimating net benefit for each outcome (δ) and overall net benefit (Δ). Of 985 adolescents (age = 15·3 (sd 0·7 years; 46·7 % boys), those in less advantaged group were 12·5 % more likely to have a favourable change in weight status and NB than those in advantaged group (Δ = 12·5 % (6·1, 19·1 %)). For each outcome, net benefits were as follows: BMIz (δ = 4·2 % (0·0, 8·6)), vigorous PA (δ = 4·2 % (0·4, 8·3)), FV (δ = 3·2 % (0·9, 5·5)), SB (δ = 0·8 % (–1·6, 3·2)), SPB (δ = −0·2 % (–1·1, 0·6)), moderate PA (δ = 0·2 %) (–0·7, 1·1) and walking (δ = 0·2 % (–0·2, 0·6)). Results showed an overall beneficial effect of the PRALIMAP-INÈS trial in reducing social inequalities in weight and NB among adolescents with overweight or obesity. Long-term effectiveness could be expected by reducing social inequalities in NB.

Mental health disorders are prevalent among adolescents and evidence suggests that stigma, poor mental health literacy (MHL) and access are key barriers to help-seeking for mental health difficulties in adolescence and throughout life. The study purpose is to assess existing mental health knowledge, stigma and help-seeking behaviour among adolescents in Uganda. A total of 889 secondary school students in Kampala completed standardised self-report questionnaires. The results reveal low-to-moderate levels of mental health knowledge (MAKS, range 12–60, M = 16.35, SD = 5.18, AMHLQ, range 33–138, M = 64.01, SD = 12.98), stigma (RIBS, range 4–20, M = 12.30, SD = 3.52) and prejudice towards people with mental illness (PPMI-TR, range 133–19, M = 73.85, SD = 13.38). Knowledge correlated with stigma (r = 0.166 and r = 0.135, p < 0.01), and with one’s capacity to assess own mental health (SELF-I range 5–25, M = 12.34, SD = 4.4). Adolescents are open to seek help from mental health professionals but reluctant to seek it from most accessible help sources like schoolteachers. The findings provide insights for future mental health-promoting and anti-stigma interventions for adolescents.

The objectives of the present study were (a) to determine the effects of a 12-week intervention using wearables promoted through physical education classes on physical activity, body composition, physical fitness and psychological well-being of overweight or obese adolescents; and (b) to analyze the differences in outcomes based on gender and baseline physical activity. Seventy-three overweight and obese adolescents (mean age: 13.44 ± 1.12 years) were randomly assigned to an experimental group (EG) or control group (CG). The EG used a physical activity wearable for 12 weeks. Both groups were assessed before and after the intervention. Regarding primary outcomes, the EG showed an increase in physical activity (p = 0.048) and reductions in body mass index (p = 0.007), fat mass (p < 0.001), and sum of 3 skinfolds (p = 0.002), with moderate-to-large effect sizes (η2 > 0.09). According to the secondary outcomes, improvements in physical fitness were limited, with increases observed only in abdominal muscular endurance, and these changes were also present in the CG. Subgroup analyses showed that females and adolescents with low baseline physical activity experienced greater benefits, particularly in fat-related variables (p < 0.001–0.037), with large effect sizes (η2 > 0.14). Additionally, adolescents with greater exposure to the wearable-based intervention showed more consistent improvements in fat-related outcomes (p < 0.001–0.032), with large effect sizes (η2 > 0.25). In conclusion, a wearable-based intervention promoted through physical education classes may contribute to meaningful improvements in body composition, particularly among females and previously inactive adolescents who are overweight or obese. However, effects on physical fitness and psychological well-being were limited, highlighting the importance of intervention design, adherence, and complementary motivational strategies.

A limited intake of free and added sugars is recommended due to potential associations with adverse health effects and nutrient inadequacy. However, the impact of free and added sugars intakes on dietary intake is unknown in Swedish adolescents. This study investigated associations of free and added sugars intakes with nutrient and food consumption. Data were derived from the Riksmaten Adolescents 2016–2017 cross-sectional survey, including a nationally representative sample of 3099 adolescents, aged around 12, 15 and 18 years, which provided two 24-h recalls. Median nutrient and food group intakes were compared across sugars intake quintiles, with adjustments for sex, school year and energy misreporting. Inverse associations were observed for almost all micronutrients, dietary fibre, essential fats and food groups commonly included in a healthy diet (e.g. vegetables, fruit, dairy products, meat, fish). However, positive associations between free sugars and vitamin C intake were observed, with fruit juice influencing intake trends. Total energy intake was not positively associated with free or added sugars intakes. Higher intakes of free and added sugars (> 12·9 and > 11·3 % of total energy intake) significantly reduced the likelihood of meeting nutrient reference values. However, for critical nutrients within the adolescent diet (vitamin D, Se, dietary fibre and polyunsaturated fats), lower odds of meeting reference values were observed even at lower intakes of free and added sugars. To conclude, with increasing sugars intake, Swedish adolescents appear to displace nutrient-dense foods with sugars-rich foods, emphasising differences in dietary patterns between those with lower v. higher free and added sugars intake.

This study explores the association between school-based foreign language (FL) instruction and mathematical achievement among 15-year-old students, using data from the 2018 Programme for International Student Assessment (PISA). Two complementary analyses were conducted: a large-scale model (n = 300,656) examining the relationship between time spent in FL learning and maths performance across 73 countries and a machine learning (ML) approach (random forest (RF); n = 53,459) identifying specific programme features that most strongly influence this relationship. Results show that longer exposure to FL instruction was associated with a modest but statistically robust increase in maths scores (β = 0.08, p < .001), even after controlling for socioeconomic and contextual factors. Among programme characteristics, the integration of multicultural curricula emerged as a prominent predictor of higher maths performance. These findings indicate that sustained, culturally enriched FL learning is positively associated with numeracy outcomes, with implications for equity in academic achievement and cross-disciplinary performance.

Evidence on the association between self-esteem and suicide risk (SR) among adolescents in Latin America is limited. To address this gap, we examined this association in secondary school students from northern Peru. We performed an analytical cross-sectional study based on secondary data collected in 2022 from 1,314 adolescents attending 5 secondary schools. SR was assessed using the Plutchik Suicide Risk Scale, while self-esteem was measured with the Rosenberg Self-Esteem Scale. Prevalence ratios (PRs) and corresponding 95% confidence intervals (CIs) were calculated through Poisson regression with robust variance, both in crude and adjusted models. The study population comprised 54.2% males, with the majority (69%) in middle adolescence. Low self-esteem was identified in 44.7% of participants, while 29.4% presented average self-esteem. Overall, 33.3% of adolescents reported SR (95% CI: 30.8–36.0). In crude analyses, both average and low self-esteem were associated with a higher prevalence of SR compared with high self-esteem (PR = 2.30 and PR = 4.11, respectively). In adjusted models, average self-esteem was associated with a 42% higher prevalence (PR = 1.42) and low self-esteem with a 67% higher prevalence (PR = 1.67). One in three adolescents presented an SR, underscoring the need to integrate school- and community-based programs that promote self-esteem within suicide prevention.

Poor mental health is a growing issue among adolescents, with untreated conditions persisting into adulthood and typically increasing in severity. South Africa’s mental health legislation faces key barriers to implementation due to limited access to treatment and support, as well as persistent challenges related to stigma, privacy concerns and affordability. Mobile mental health (M-mHealth) could be a sustainable and scalable alternative for reducing unmet needs for psychological services. This study aims to explore adolescents’ perceptions, attitudes and intentions regarding M-mHealth interventions. The study involved two phases and used an explanatory sequential mixed-methods approach. 71 adolescents completed the survey in phase 1, while 56 adolescents participated in 9 focus group discussions in phase 2. Qualitative and quantitative data were analysed using thematic and descriptive analyses, respectively. Findings from both phases were integrated using the pillar integration process. Findings show that adolescents have a limited understanding of the broader concept of mental health, and stigma persists through the use of terms like “crazy” and “bewitched.” Adolescents view M-mHealth positively because of its low cost, convenience and privacy. However, issues like data costs, smartphone affordability, and limited privacy at home could hinder its use. M-mHealth extends beyond the health sector and is constrained by infrastructural and socio-cultural barriers, including privacy concerns, high data costs, and stigma.

Suicide is a significant global public health concern, particularly among adolescents, with substantial implications for economies, societies and individuals’ mental well-being. Understanding its patterns and intention and psychosocial determinants in a given context can suggest potential intervention points. This population-based cross-sectional study aimed to document suicidal ideas, behaviors and intensity among youths aged 14 to 25 in the Nairobi metropolitan area and associated socio-economic position, demographic indicators and potential intervention points. A diverse sample of 1,972 participants was recruited from urban and peri-urban settings within the Nairobi metropolitan area. Data analysis included descriptive statistics, chi-square tests and logistic regression. Our findings confirm a high prevalence of suicidal ideas and behavior in the youth (19.9% and 3.6%, respectively), with very few significant differences between the urban and peri-urban areas. The severity of suicidal ideation and behavior reported methods and reasons, and the socio-demographic profile of participants, point to multiple potential intervention targets. These findings ought to be used to design, manage and evaluate suicide prevention programs.

Pulmonary arterial hypertension leads to dyspnoea, fatigue, and oxygen desaturation, limiting activities of daily living and functional capacity. This study aimed to evaluate the impact of pulmonary arterial hypertension on activities of daily living performance, functional capacity, peripheral muscle strength, oxygen dynamics, and energy expenditure. Eighteen adolescents and young adults with pulmonary arterial hypertension (10 females, 8 males; age 9–30 years) and 15 healthy controls (10 males, 5 females; age 9–30 years) were included. Peripheral muscle strength was assessed using a handheld dynamometer, functional capacity via the 6-minute walk test, and muscle oxygenation through near-infrared spectroscopy. Lower-limb endurance was evaluated with the 1-minute sit-to-stand test and activities of daily living performance with the Glittre Activities of Daily Living test. Compared to controls, the pulmonary arterial hypertension group had significantly lower 6-minute walk test distance (441.9 m versus 636.9 m; p < 0.001), reduced sit-to-stand repetitions (28 versus 42.1; p < 0.001), weaker peripheral strength, and lower minimum muscle oxygen saturation (24.9% versus 51.8%; p < 0.001). Glittre Activities of Daily Living test duration was longer (143 s versus 105 s; p < 0.001), with greater oxygen desaturation (−13% versus −1%; p < 0.001), higher dyspnoea scores using modified Borg scale (5 versus 1; p < 0.001), and blunted heart rate response (ΔHR [change in heart rate]: 32 versus 64; p = 0.011). These findings demonstrate that pulmonary arterial hypertension significantly impairs both cardiopulmonary and peripheral muscle function. Protecting muscle health and improving functional capacity should be prioritised to enhance quality of life in this population.

Myopia is a critical public health issue, particularly among adolescents. This study investigates the association between adherence to a Mediterranean-style diet and the odds of myopia in US adolescents. A cross-sectional analysis was conducted using National Health and Nutrition Examination Survey (NHANES) data from 2005 to 2008, involving 2473 participants aged 12–18 years. Adherence to the diet was assessed using the alternate Mediterranean diet (aMED) score. Myopia was defined as a spherical equivalent of ≤–0·50 dioptres (D). Multivariable logistic regression models adjusted for age, sex, race, education level, BMI, poverty income ratio and total energy intake were used to examine the association between aMED and myopia. Additionally, restricted cubic spline regression was used to explore non-linear relationships, and mediation analysis was conducted to identify potential biological pathways. Of the participants (median age: 15 years; 50·5 % male), 41 % were identified as having myopia. Participants with myopia had significantly lower aMED scores compared with non-myopic individuals (P < 0·05). Higher adherence to the aMED was associated with lower odds of myopia (OR: 0·830, 95 % CI 0·712, 0·968). A significant dose–response relationship was observed, with adolescents in the highest aMED quintile having a 41 % lower odds of myopia compared with the lowest quintile (OR: 0·592, 95 % CI 0·368, 0·952). The association was partially mediated by dietary cholesterol and eicosatetraenoic acid. In conclusion, adherence to a Mediterranean-style diet in adolescents is associated with a lower odds of myopia. Addressing diet quality may mitigate health risks related to myopia development.

Youth social action—activities such as volunteering, campaigning, and fundraising—has gained traction in the UK and internationally in recent years as governments have supported initiatives to encourage adolescents to develop a ‘habit’ of social action. However, there is not convincing evidence on what a habit of social action is. This study involved a questionnaire with 4518 16–20-year-olds in the UK and finds that moral and civic virtue identity, perceived behavioural control, goal direction, and subjective norms are related to a habit of youth social action. A key contribution of this study is the development and application of a new measure of virtue identity—the Virtue Identity Measure—to which we pay particular attention in this article.

This study investigates the potential of rumination-focused cognitive behavioural therapy (RFCBT) to address core issues in adolescents with social anxiety disorder (SAD). Specifically, it examines RFCBT’s effectiveness in reducing internalized shame, negative interpretation biases, and rumination, which contribute significantly to their social anxiety. The present study employed a quasi-experimental design with a pre-test, post-test, and follow-up phase. The population of the study included all adolescents with SAD in Ahvaz, Iran, in 2023. The sample consisted of 48 adolescents with SAD who were selected using convenience sampling and then randomly assigned to either the RFCBT group or the control group (24 participants per group). The research instruments included the Social Anxiety Questionnaire, the Child Internalized Shame Scale, the Interpretation Bias Questionnaire, and the Rumination Response Scale (RRS). Repeated measures analysis of variance (ANOVA) was used to analyse the data. The findings indicate that RFCBT had a significant effect on reducing internalized shame, interpretation bias, and rumination (p<0.01) in adolescents with SAD, with results maintained at follow-up. This study adds to the evidence that RFCBT can be helpful for anxiety disorders in adolescents. RFCBT seems to work by addressing negative self-views, biased interpretations, and repetitive negative thinking patterns. More research is needed to determine if these benefits are sustained long-term and if RFCBT can improve social skills and overall well-being for adolescents with social anxiety.

Afro-Colombian adolescents in Tumaco face high mental-health risks due to armed conflict and structural marginalization. We tested the short-term efficacy of the 3C program to strengthen resilience, compassion, and prosocial behavior and to reduce anxiety, depression, and PTSD. Mixed-methods cluster RCT with concurrent triangulation; multilevel mixed-effects models with multiple imputation; assessments at baseline, 6, and 9 months. Resilience increased by 13.14 points at 6 months (large effect, d = 0.89) and remained elevated at 9 months. Anxiety and PTSD screenings were lower in the intervention group across follow-ups. Compassion and prosocial behavior improved at 6 months but attenuated by 9 months. Depression screenings decreased at 6 months and rebounded at 9 months. Qualitative data aligned with these patterns (students reported sustained use of stress-management skills and peer support). 3C demonstrated short-term efficacy for resilience, anxiety, and PTSD but showed limited durability for compassion, prosociality, and depression without ongoing reinforcement. The pattern of effect attenuation—particularly the complete depression rebound—indicates that 3C provides a foundational component requiring integration with booster sessions to sustain socioemotional gains.