Background/Objectives: Even with solid proof of its benefits for cardiovascular health and metabolism, adherence to the Mediterranean Diet (MD) in Spain has noticeably declined in recent years. The socioeconomic changes occurring in recent decades have prompted shifts in cooking habits and in how food is socially experienced, particularly among children and adolescents. The MD is more than just food: it is a cultural tradition and a lifestyle, rich in food and cooking skills, and food wisdom passed down over generations. When these practices fade, it affects both health and the environment, making them vital components in strengthening support for food knowledge, cooking abilities, and a healthier lifestyle. Considering these shifting dietary patterns and the growing need for targeted educational strategies, the present study aimed to investigate the association between cooking skills, MD-related health literacy, and adherence to the Mediterranean Diet across different developmental stages: childhood, adolescence, and adulthood in a sample of the Spanish population. Additionally, a secondary objective was to identify potential critical windows for intervention based on the strength of these associations. Methods: This cross-sectional study included 832 Spanish participants grouped by age: children and early adolescents (n = 408), older adolescents (n = 136), and adults (n = 288). Cooking skills were assessed using CooC11 for children and FCSk for older groups. Adults also completed Lit_MEDiet to assess MD-related health literacy. Adherence was measured with KIDMED (children/adolescents) and MEDAS (adults). Spearman correlations and standardized linear regressions were used. All statistical tests were two-sided, and statistical significance was set at p < 0.05. Results: In children, no significant association was found between cooking skills (CooC11) and KIDMED scores (β = 0.008; p = 0.875). Among adolescents, a strong positive association emerged between FCSk and KIDMED (β = 0.313; p < 0.001; ρ = 0.371), indicating a large, standardized effect and suggesting that this stage is particularly sensitive to food skills. In adults (18+), both food and cooking skills (FCSk) (β = 0.189; p = 0.001) and MD-related health literacy (Lit_MEDiet) (β = 0.187; p = 0.004) were moderately associated with MEDAS scores. Conclusions: These findings suggest that mid-adolescence could represent a favourable developmental window where food skills may hold potential to influence positive dietary behaviours. Regarding adults, the results indicate that combining practical and educational components appears to beneficial for dietary quality. Overall, this study supports the relevance of age-tailored public health strategies to potentially enhance long-term adherence to the Mediterranean Diet.

Introduction: Food and cooking skills (FCSks) are defined as a complex, interrelated, and person-centred set of skills, necessary to provide and prepare safe, nutritious, and culturally acceptable meals for all members of the household. Recent studies have associated higher FCSk with healthier eating habits and better health. This study aimed to validate a Portuguese version of a tool to assess and describe FCSk in young adults. Methods: A cross-sectional study used an online anonymous questionnaire that was disseminated to students from three Portuguese Higher Education Institutes. The questionnaire validation included Cronbach alpha and confirmatory factor analysis (CFA). The Mann-Whitney test was used for evaluating sample differences and Pearson correlation for association among variables. Results: Internal consistency reliability was 0.89 for cooking skills (CSks) and 0.87 for food skills (FSks). A moderate positive correlation was found between CSks and FSks confidence (r = 0.658, p < 0.01). CFA presented a good adjustment model for most of the fit indices, indicating the adequacy of the questionnaire. The CSks score was 74.1 ± 21.2 (moderate) and the food Skills was 94.2 ± 20.8 (high). Cook pulses, steaming food, and planning meals ahead scored the lowest value, while boiling or simmering food, chopping, peeling vegetables, and reading the best-before date scored the highest value. No difference was found among sex (pCSk = 0.576; pFSk = 0.158), age (pCSk = 0.566; pFSk = 0.130), body mass index classes (pCSk = 0.903; pFSk = 0.320), or course (pCSk = 0.169; pFSk = 0.126). The greatest interest in gastronomy and frequency of meal preparation is associated with higher FCSk (p < 0.05). Conclusion: This research validated a Portuguese version of a tool to assess FCSk among young adults. Internal consistency reliability was adequate. Confirmatory factor analysis returned good psychometric properties for the questionnaire. Authors identified lower FCSk competencies in cooking pulses and vegetables, which are healthy and sustainable foods. This may compromise the adoption of healthy eating behaviours, so promoting FCSk in young adults may pose a strategy for nutrition and public health in reducing diet-related diseases. This tool may be used to identify opportunities for intervention in public health nutrition.