Lunch-time food source is associated with school hour and school day diet quality among Canadian children.

BACKGROUND
There is limited research on the dietary behaviours of Canadian children at school, including where students obtain food from during school hours or whether lunch-time food source influences diet quality.

METHODS
Nationally representative cross-sectional data from 24-h dietary recalls were analysed from the 2004 Canadian Community Health Survey (n = 4589). Dietary outcomes included school hour and school day dietary intakes and School Healthy Eating Index (S-HEI) scores. Survey-weighted covariate-adjusted linear regression models examined differences in dietary outcomes across lunch-time food source groups.

RESULTS
The majority of children (72.8%) reported bringing lunch from home, whereas fewer students obtained lunch from off-campus locations (11.6%), schools (9.6%) or skipped lunch (5.9%). Compared to off-campus lunches, home-packed lunches were significantly higher in fibre, vitamins A, D and C, thiamin, magnesium, iron, grains, vegetables and fruit, but lower in total calories, fat and calories from minimally nutritious foods. Average school hour diet quality required improvement for all age groups, although S-HEI scores did not differ significantly by lunch-time food source among 6-8-year-old children. However, for children age 9-17 years, bringing a home-packed lunch was associated with significantly higher S-HEI scores compared to students obtaining lunch from off-campus locations. After adjusting for age and sex, lunch-time food source was also significantly associated with whole day dietary quality.

CONCLUSIONS
Although the nutritional quality of off-campus lunches was lower than home-packed lunches, the quality of foods was suboptimal, regardless of food source. Strategies are needed to enhance access to nutritious foods on campus and improve the nutritional quality of packed lunches, which supply the majority of lunch-time foods consumed by Canadian children.