A Mediterranean diet (MedDiet) has emerged as a crucial dietary choice, not only in attenuating various adolescents’ metabolic health issues but it has also been associated with improved cognitive and academic achievement. However, few studies have established patterns of food consumption linked to both cognitive and academic achievement in adolescents living in a developing country with non-Mediterranean-based food. Methods: This cross-sectional study included 1296 Chilean adolescents (50% girls) aged 10–14 years. The MedDiet Quality Index was used to assess adherence to the MedDiet in children and adolescents. Through cluster analysis, four distinct dietary patterns were identified: Western diet (WD = 4.3%); low fruit and vegetables, high-sugar diet (LFV-HSD = 28.2%); low fruit and vegetables, low-sugar diet (LFV-LSD = 42.2%); and the MedDiet (25.3%). A mixed-model analysis was conducted to compare these clusters and their relationships with cognitive and academic achievements. Principal component analysis was performed to identify four primary cognitive domains: working memory, cognitive flexibility, inhibitory control, and fluid reasoning. Academic achievement was determined with five school subjects (Language, English, Mathematics, Science, and History) and included the Academic-PISA score derived from the mean scores in Language, Mathematics, and Science. Results: A marked difference was observed between the four clusters, which was mainly related to the consumption of sugar, ultra-processed foods, fruits, and vegetables. According to cognitive performance, the MedDiet group showed higher performance across all domains than the LFV-HSD, LFV-LSD, and WD groups. Regarding academic achievement, the WD underperformed in all analyses compared to the other groups, while the MedDiet was the unique profile that achieved a positive difference in all academic subjects compared to the WD and LFV-HSD groups (p < 0.05). Conclusions: These findings suggest that higher adherence to Mediterranean-style-based patterns and better food quality choices are associated with improved cognitive and academic achievements.

Propósito: Determinar patrones en la paradoja “Fat but Fit” y su impacto en el rendimiento cognitivo y logro académico en adolescentes chilenos. Esta paradoja sugiere que una mayor condición física puede mitigar los efectos negativos del exceso de adiposidad. Métodos: Estudio transversal, parte del Proyecto Cogni-Acción, incluyó 1,296 adolescentes (10-14 años). Se identificaron patrones de adiposidad/condición física mediante análisis de clases latentes y se evaluaron dominios cognitivos y calificaciones académicas. Resultados: Se encontraron diferencias significativas y positivas en las puntuación cognitiva global y puntuación académica entre adolescentes “thin-fit” versus “unfit” (“thin-unfit” y “fat-unfit”, p = .023 y p = .007, respectivamente) y “thin-fit” versus “fat” (“fat-fit” y “fat-unfit”, p = .028 y p < .001, respectivamente). Conclusión: Una mayor condición física se asocia con mayor rendimiento cognitivo, mientras que menor adiposidad a un mayor logro académico. La paradoja “Fat but Fit” podría influir de manera diferenciada en estos resultados.

Biological aging clocks offer estimations of aging and dementia, yet scalability is limited. We introduce a large-scale, cross-national speech clock derived from 2928 individuals across five Latin American countries, spanning healthy controls (HCs), mild cognitive impairment (MCI), Alzheimer’s disease (AD), and non-language/language-dominant frontotemporal dementia (nldFTD/ldFTD). Multimodal acoustic and linguistic features were trained with supervised models to estimate chronological age, generating speech age gaps (SAGs) as cross-sectional markers of deviations from chronological age, with positive values interpreted as relatively older-appearing speech profiles. SAGs differentiated diagnostic groups (HCs < patient groups, with AD < nldFTD < ldFTD). This pattern was associated with clinical/cognitive domains. SAGs correlated with phosphorylated tau (p-Tau217) in AD and social exposome in HCs and AD. Brain clocks (structural/functional/combined) were associated with SAG in AD, nldFTD, and ldFTD. Epigenetic age correlated with SAGs in HCs and AD across Hannum, Retroclock, and OMICmAge, whereas ldFTD associations were limited to Retroclock and OMICmAge. These results indicate that SAGs capture cross-sectional multilevel aging-related variation and may offer a scalable, culturally adaptable, low-cost biomarker candidate for research in underrepresented global settings.

Global concern has deepened in recent decades over alarming rates of obesity, sedentarism, insufficient physical activity and fitness levels, and unhealthy eating habits in children and adolescents. Parallelly, we have witnessed increased poverty and socioeconomic vulnerability worldwide. Understanding the intrinsic relationship between physical and cognitive health is crucial, and mounting evidence suggests a significant association. However, over 80% of existing data originate from high-income countries, representing a negligible fraction of the world's children. UNICEF projections indicate that by 2030, low- and low-middle-income countries will be home to approximately 63% of the global child and adolescent population. This highlights a substantial knowledge gap which the Cogni-Action Project, conducted in Chile, helps to address. Notably, Chile faces significant challenges, with child overweight-obesity rates reaching 54%, ranking highest in sedentarism, physical inactivity, sugary soft-drink consumption, and educational scores stagnant. Moreover, wealth inequality is stark, with the top 10% of the population owning 77% of the wealth. The Chilean Cogni-Action Project collected comprehensive data over three years (2017-2019) from 1,296 schoolchildren (10-14 years old) in the Valparaíso region. These data encompassed 789 variables spanning physical, psychosocial, cognitive, and lifestyle factors, as well as neuroimaging variables. The present article aims to contextualize and showcase this project based on the papers published to date. As universities and research institutions worldwide pursue similar endeavors, the necessity arises to share findings and methodologies to expedite knowledge development that can inform public policy and shape the agendas of pertinent institutions.