Dietary patterns and health-related quality of life among Iranian adolescents.

Purpose: Examining the associations of a-posteriori-defined dietary patterns and health-related quality of life (HRQOL) among Iranian adolescents.

Methods: This cross-sectional study was conducted among 900 apparently healthy students (mean age 15.33 years; 53.0% female) during 2020-21. The validated Persian version of self-report Pediatric Quality of Life Inventory™ Version 4.0 Generic Core Scales (PedsQL) for healthy adolescents was used in an online survey to assess HRQOL. Total, physical health, psychosocial health, emotional functioning, social functioning, and school functioning PedsQL scores were calculated, and impaired HRQOL was defined as > 1 standard deviation below the total population sample mean PedsQL scores. A validated food frequency questionnaire was used to assess dietary intakes during telephone interviews. Daily intakes of 20 predefined food groups were calculated and submitted to the principal component factor analysis to identify a-posteriori-defined dietary patterns.

Results: Three major dietary patterns labeled as Mediterranean, mixed, and unhealthy were identified, of which only the Mediterranean pattern characterized by high intakes of vegetables, fruits, olives, potatoes, eggs, nuts and legumes, pickles, low-fat dairy, fish, poultry, and vegetable oils was consistently associated with HRQOL. Controlling for covariates in the multivariable-adjusted binary logistic regression analysis, participants in the top tertile of Mediterranean pattern score were less likely to have impaired HRQOL than those in the bottom tertile (total: OR 0.25; physical health: OR 0.35; psychosocial health: OR 0.15; emotional functioning: OR 0.17; social functioning: OR 0.15; and school functioning: OR 0.18; all P < 0.010).

Conclusion: Current findings indicate that an a-posteriori-defined Mediterranean-style dietary pattern is associated with better HRQOL among healthy Iranian adolescents.