Background/objectives: This longitudinal study describes the relationship between young children's screen time, dietary habits and anthropometric measures. The hypothesis was that television viewing and other screen activities at baseline result in increased consumption of sugar-sweetened beverages (SSB) and increased BMI, BMI z-score and waist to height ratio (WHtR) two years later. A second hypothesis was that SSB consumption mediates the association between the screen activities and changes in the anthropometric measures.
Subjects/methods: The study is a part of the prospective cohort study IDEFICS ("Identification and prevention of dietary and lifestyle-induced health effects in children and infants"), investigating diet, lifestyle and social determinants of obesity in 2 to 9-year-olds in eight European countries (baseline n=16,225, two-year follow-up; n=11,038). Anthropometry was objectively measured, and behaviours were parent-reported.
Results: The main hypothesis was supported, but the second hypothesis was not confirmed. The odds ratio of being in the highest quintile of % change in WHtR was 1.26 (95% CI: 1.17-1.36) and in BMI 1.22 (95% CI: 1.13-1.31), for each hour per day watching television. The odds ratio of having increased SSB consumption was 1.19 (95% CI: 1.09-1.29) for each hour per day watching TV. The associations for total screen time were slightly weaker.
Conclusions: The results indicate substantial effects of TV viewing and other screen activities for young children, both on their consumption of sugary drinks and on an increase in BMI and central obesity. Our findings suggest that television viewing seems to have a stronger effect on food habits and anthropometry than other screen activities in this age group.