BACKGROUND: television, computer and other causes of increased inactivity are reported to be among the major causes of obesity. This cross-sectional study was aimed to evaluate the effect of television viewing and other daily activities on body mass index (BMI) z-score of early adolescents. METHODS: a total of 860 students and their parents (581) from different socioeconomic level schools were included. They were instructed to fill in a self-designed questionnaire. Weight and height were measured, and BMI z-scores were calculated. RESULTS: BMI z-score was higher in boys and in those attending high socioeconomic level schools. Children with a BMI z-score >2SD watched television (2.5 ± 0.9 h/day) longer than those with <-2SD (1.6 ± 0.8 h/day) (P=0.027). The three categories (<-2SD, -2SD-2SD, >2SD) differed significantly according to maternal (P<0.05) and paternal (P<0.005) BMI. Linear logistic regression analysis revealed that socioeconomic level, maternal BMI and paternal BMI are factors affecting BMI z-score significantly. CONCLUSION: genetic and/or family environment which may affect the nutrition and activity of adolescents seems to be the most important factor affecting their BMI z-score.
BACKGROUND: television, computer and other causes of increased inactivity are reported to be among the major causes of obesity. This cross-sectional study was aimed to evaluate the effect of television viewing and other daily activities on body mass index (BMI) z-score of early adolescents. METHODS: a total of 860 students and their parents (581) from different socioeconomic level schools were included. They were instructed to fill in a self-designed questionnaire. Weight and height were measured, and BMI z-scores were calculated. RESULTS: BMI z-score was higher in boys and in those attending high socioeconomic level schools. Children with a BMI z-score >2SD watched television (2.5 ± 0.9 h/day) longer than those with <-2SD (1.6 ± 0.8 h/day) (P=0.027). The three categories (<-2SD, -2SD-2SD, >2SD) differed significantly according to maternal (P<0.05) and paternal (P<0.005) BMI. Linear logistic regression analysis revealed that socioeconomic level, maternal BMI and paternal BMI are factors affecting BMI z-score significantly. CONCLUSION: genetic and/or family environment which may affect the nutrition and activity of adolescents seems to be the most important factor affecting their BMI z-score.
Authors: I Janssen; P T Katzmarzyk; W F Boyce; C Vereecken; C Mulvihill; C Roberts; C Currie; W Pickett Journal: Obes Rev Date: 2005-05 Impact factor: 9.213
Authors: Aviva Must; Linda G Bandini; David J Tybor; Sarah M Phillips; Elena N Naumova; William H Dietz Journal: Obesity (Silver Spring) Date: 2007-07 Impact factor: 5.002