An increase in screen time (ST) is reportedly associated with insulin resistance and obesity in children. However, most studies are of TV viewing but not smartphone use. Also, little is known of the relationship between ST and diet. In this study, we clarified the relationships among ST including smartphone use, lifestyle factors including dietary content, and obesity. Cross-sectionally analyzed were 1393 children between 11-15 years of age. ST (min/day) was classified into 4 groups: <120, 120-179, 180-239, ≥240. The associations of each group with dietary content and obesity were investigated. Smartphone usage time significantly increase and sleep duration significantly decreased as ST increased, which was not the case for physical activity. There was no significant difference in energy intake between the 4 groups of ST either for boys or girls, but intake of protein, vegetables green and yellow, other vegetables, and fish and shellfish decreased significantly as ST increased, as did increase in beverage intake. In addition, the association with obesity was significantly increased in the ≥240 ST group compared to the <120 ST group (1.93[1.14-3.28]).

In conclusion, the increase in ST including smartphone usage was suggested to be associated with various unfavorable lifestyles including dietary habits that could be connected to obesity.


I. Ikeda: None. K. Fujihara: None. R. Nedachi: None. S.Y. Morikawa: None. H. Ishiguro: None. M.H. Yamada: None. Y. Matsubayashi: None. T. Yamada: None. H. Sone: Research Support; Self; Kyowa Hakko Kirin Co., Ltd., Novartis AG, Ono Pharmaceutical Co., Ltd., Taisho Pharmaceutical Co., Ltd., Takeda Pharmaceutical Co.

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