Association between junk food consumption and mental health in a national sample of Iranian children and adolescents: the CASPIAN-IV study.

Objectives: The consumption of high energy and low nutritional content foods, which are known as junk foods, has increased. The aim of this study was to evaluate the association between junk food intake and mental health in a national sample of Iranian children and adolescents.

Method: Data were obtained from a surveillance system entitled CASPIAN-IV (Childhood and Adolescence Surveillance and Prevention of Adult Non communicable Disease) study of school students, ages 6 to 18 y in Iran. The students and their parents completed two sets of reliable questionnaires obtained from Global School Health Survey translated to Persian. The student questionnaire comprised several questions such as psychiatric distress (worry, depression, confusion, insomnia, anxiety, aggression, and worthless) and violent behaviors (physical fighting, being a victim, and bullying). The junk foods consisted of sweets, sweetened beverages, fast foods, and salty snacks.

Results: In the sample of 13 486 children and adolescents, the frequency of junk food consumption was significantly associated with psychiatric distress (P < 0.001). There was a significant association between violent behaviors and intake of junk foods (P < 0.001) except for sweets, whereas the association between sweetened beverages consumption and being a victim was not significant (P > 0.05). Additionally, the results of logistic regression showed that daily consumption of sweetened beverages and snacks significantly increased the odds of self-reported psychiatric distress. Also, daily consumption of salty snacks was significantly associated with violent behavior, including physical fighting (odds ratio [OR], 1.39; 95% confidence interval [CI], 1.21-1.60), being a victim (OR, 1.19; 95% CI, 1.04-1.37), and bullying (OR, 1.55; 95% CI, 1.32-1.82).

Conclusion: Junk food consumption may increase the risk for psychiatric distress and violent behaviors in children and adolescents. Improvement of eating habits toward healthier diets may be an effective approach for improving mental health.