DESIGN: We analysed data of children who participated in the Health Survey for England from 1997 to 2016 (n=34 235). This repeated cross-sectional survey reported weight loss attempts and sociodemographic characteristics. Body weight and height were measured by trained interviewers, and body mass index for age z-score was calculated. Multivariable logistic regression was used to investigate the sociodemographic determinants.
SETTING: England.
PARTICIPANTS: Children (8-17 years).
MAIN OUTCOME MEASURES: Weight loss attempts by year, age group, gender, BMI for age z-score, ethnicity and household income.
RESULTS: The prevalence of reported weight loss attempts increased significantly from 21.4% (1997-1998) to 26.5% (2015-2016). The increase was significant for boys, older children, Asian children, children from lower income households and in all categories of BMI for age z-score. Significant predictors of weight loss attempts included having overweight (8-12 years old, OR 4.01 (%CI 3.47 to 4.64); 13-17 years old, OR 1.96 (%CI 1.58 to 2.42)) or obesity (8-12 years old, OR 13.57 (%CI 11.94 to 15.43); 13-17 years old, OR 4.72 (%CI 3.94 to 5.66)) as well as being older, girls, from ethnic minority groups or low household income.
CONCLUSION: The prevalence of reported weight loss attempts among children is increasing at a faster rate than the rise in excess weight and includes an increasing proportion of children with a 'healthy' weight. The increase in the prevalence of reported weight loss attempts among children is greatest among subgroups with lower baseline prevalence.
METHODS: This cross-sectional study involved 1,404 school adolescents aged 12 years (46% boys and 54% girls). Socio-demographic, dietary and physical activity data were collected using questionnaires whilst body weight and height were measured and body mass index was classified based on WHO BMI-for-age Z-scores cut-off.
RESULTS: A multivariable linear regression model showed that BMI z-score was positively associated with parents' BMI (P<0.001), birth weight (P=0.003), and serving size of milk and dairy products (P=0.036) whilst inversely associated with household size (P=0.022). Overall, 13.1% of the variances in BMI Z-scores were explained by parents' BMI, birth weight, servings of milk and dairy products and household size.
CONCLUSION: This study found important determinants of body weight status among adolescents mainly associated with family and home environmental factor. This evidence could help to form the effective and tailored strategies at the earliest stage to prevent obesity in this population.