Perceptions of weight and associated factors of adolescents in Jiangsu Province, China.

OBJECTIVE: To describe perceptions of weight of adolescents and associated factors.

DESIGN: Cross-sectional survey in 2002.

SETTING: Eight public middle schools in two distinct socio-economic areas of Jiangsu Province, China.

SUBJECTS: Eight hundred and twenty-four adolescents (aged 12-14 years) and 628 of their parents.

METHODS: Self-administered questionnaires for students and their parents were used to collect the data. Height and weight of the students were measured.

RESULTS: One-third of the girls perceived themselves as overweight, while only 8.9% were actually overweight or obese according to the World Health Organization definition. On the other hand, 15.0% of the girls considered themselves underweight, while 5.6% were underweight according to the definition. Among the boys, one-fifth of those defined as overweight perceived their weight as normal. Furthermore, 23.9% perceived themselves as underweight when in fact only 4.9% were classified as underweight according to the definition. About one-quarter of the students dieted in the past year. Adolescents who perceived themselves to be overweight dieted and skipped breakfast more often. They also had lower intake frequencies of animal foods, Western foods and milk/yoghurt. No disparity was observed in the intake frequency of fruits and vegetables between the groups of different weight perception. Parents' weight norms seemed to favour overweight in both genders, but especially among boys.

CONCLUSIONS: Both overweight and underweight concerns were common among girls, while a higher body weight was favoured by normal-weight boys and their parents. Distorted weight perceptions in adolescents, as well as dieting, are problems that need appropriate intervention.