Television viewing behaviour and associations with food habits in different countries.

OBJECTIVE: Several environmental factors influence adolescents' food habits and television (TV) viewing is thought to be one of these factors. The purpose of the present study was to describe sociodemographic differences in TV viewing and to examine associations of TV viewing with the consumption of sweets, soft drinks, fruit and vegetables in different countries. METHODS: Data were collected from 162,305 young people completing the 2001/02 Health Behaviour in School-Aged Children survey, a World Health Organization cross-national study on health and health behaviours among 11-, 13- and 15-year-old school pupils. Analyses of variance were used to examine sociodemographic differences in TV viewing and logistic regression analyses to examine associations between TV viewing and food habits. RESULTS: Large differences were found between countries in reported daily TV viewing time, from an average of 2.0 h in Switzerland to 3.7 h in Ukraine. The results indicate that those most likely to watch TV are boys, 13-year-olds and pupils of lower socio-economic status. Those who watched more TV were more likely to consume sweets and soft drinks on a daily basis and less likely to consume fruit and vegetables daily, although the latter associations were not so apparent among Central and Eastern European countries. CONCLUSIONS: Given the high TV viewing rates among adolescents and the association with less healthy food options, many young people are at increased risk of overweight or obesity. Interventions to modify TV viewing behaviour are needed. The findings underscore the importance of tackling socio-economic differences.

Dietary restraint in relation to nutrient intake, physical activity and iron status in adolescent females.

AIM: To investigate the prevalence of dietary restraint in a female adolescent population, and to examine the nutritional consequences of dietary restraint and its implications for iron status. METHODS: A total of 64 adolescent females, aged 14-15 years, were recruited from two all-girl schools in central London. Nutrient intake, body weight, physical activity and iron status were measured. Findings were compared between three groups of subjects classified by dietary restraint. RESULTS: Adolescents with a higher BMI percentile were more likely to be highly restrained. Scores on the dietary restraint psychometric measures were comparable with other UK studies in this age group. Energy intake was inversely related to dietary restraint (mean energy intake (SE) for each restraint group were: low 8.99 MJ (0.48), medium 7.98 MJ (0.22) and high 7.35 MJ (0.39) P < 0.05); however, a corresponding relationship between dietary restraint and reduced micronutrient intakes was not found. Highly restrained eaters obtained more of their energy intake from bread, fruit and cheese and less from meat, meat products and confectionery. Levels of physical activity were not significantly different between the dietary restraint groups. There was a poor relationship between reported energy intake and estimated energy expenditure. Haematological parameters of iron status were similar across the restraint groups. CONCLUSIONS: Dietary restraint was exercised by the consumption of a "healthy eating diet". Dieting was not related to a lower iron status; however, the low dietary iron intake and poor iron status of the whole sample is of concern.