Beverage Consumption Patterns, Beverage-Derived Energy Intake, and Adherence to Fluid Intake Recommendations Among Polish Adolescents: A Cross-Sectional Study Using the BEVQ-PL Questionnaire

Background/Objectives: Different organizations have established fluid intake recommendations for adolescents; however, studies assessing adherence typically rely on a single reference system, limiting comparisons across populations. This study assessed beverage consumption patterns and beverage-derived energy intake among Polish adolescents and examined how adherence estimates differed when recommendations issued by the European Food Safety Authority (EFSA), the Institute of Medicine (IOM), and the Polish National Institute of Public Health—National Institute of Hygiene (NIH) were applied. Methods: A cross-sectional study was conducted among 1644 secondary school students aged 14–18 years. Beverage consumption (mL/day) and beverage-derived energy intake (kcal/day) were assessed using the validated Polish Beverage Intake Questionnaire (BEVQ-PL). Adherence was defined as achieving at least 80% of the age- and sex-specific Adequate Intake (AI) from beverages, assuming that beverages provide approximately 80% of total daily water intake. Results: Water had the highest median daily intake (960 mL/day). Males consumed significantly more water than females (1080 vs. 720 mL/day; p = 0.037), whereas females consumed significantly more reduced-fat milk (2%), skim milk, plant-based and flavored milk beverages, 100% vegetable juice, and coffee with milk and sugar. Adherence differed according to the recommendation system, reaching 65.2% (EFSA), 50.6% (IOM), and 65.8% (NIH). Female sex was independently associated with higher adherence across all three reference systems, whereas older age was associated with lower adherence only according to the NIH criteria and overweight/obesity only according to the IOM criteria. Conclusions: Estimated adherence to fluid intake recommendations varied substantially according to the reference system applied. These findings highlight the importance of explicitly reporting the selected reference criteria when assessing and comparing the adequacy of beverage-derived fluid intake among adolescents.