High prevalence of obesity in low income and multiethnic schoolchildren: a diet and physical activity assessment.

The objective of the study was to assess the prevalence of obesity and/or undernutrition and evaluate diet and activity patterns among schoolchildren from an ethnically diverse low income urban population. A cross-sectional survey of 498 children aged 9-12 y from 24 schools in low income multiethnic neighborhoods in Montreal, Canada was undertaken. Height, weight, dietary intake, physical activity record, and lifestyle and demographic characteristics were measured. There was no evidence of undernutrition because linear growth was appropriate for age, but 39.4% of children were overweight (>85th percentile NHANES II). Dietary fat intake was higher in children from single-parent families (P < 0.001) and those with mothers born in Canada. Intake of vitamins A, C, iron and folate was directly related to income sufficiency. Children who did more physical activity had significantly higher intakes of energy, calcium, iron, zinc and fiber but were not heavier. Dietary intake was systematically underreported among overweight children, i.e., their reported intakes did not meet calculated energy needs. This underreporting makes it difficult to attribute the accumulated energy imbalance to either energy intake or expenditure.