School Day Diets of Canadian Children

Introduction

Studies suggest that the majority of Canadian children have poor overall diets which do not meet the 2007 Canadian national guidelines for fruit, vegetables, or dairy products. Schools could provide a platform to help improve the diets of children from diverse socioeconomic backgrounds, especially since most children will typically eat at least one meal and one to two snacks in the school environment. Examining key aspects of food consumption at school can help identify priority areas - for example, what food groups schools should target to improve nutrition outcomes among Canadian children. At the same time, understanding whether school-hour dietary quality differs among socio-demographic subgroups can also help bring resources to the most vulnerable students. Accordingly, the objectives of this study were to: 1) examine differences between school-hour and non school-hour dietary intakes, and 2) evaluate demographic and socio-economic links to school-hour diet quality among Canadian children. 

 

Research Process

Dietary data were obtained from the 2004 Canadian Community Health Survey (Cycle 2.2) which was, at the time of the study, the most recent nationally representative dietary survey for Canadians. The survey targeted residents of all ages living in all provinces of Canada, and included a dietary recall where participants were asked about food and beverages consumed from midnight to midnight on the previous day. Trained interviewers asked respondents detailed information regarding food consumed, including the types of food eaten, serving sizes, eating occasion (i.e. breakfast, lunch, dinner), and the time of consumption. This analysis used data from participants aged 6-17 years old who reported attending school full time. Food consumed between 9 a.m. and 2 p.m. on school days was considered to be eaten within school hours. Dietary variables included amount of energy, nutrients, and food groups eaten during and outside of school hours on school days, as well as the proportion of calories and nutrients obtained from foods during school hours relative to whole day intakes. The School Healthy Eating Index (School-HEI) adapted from the Canadian Healthy Eating Index (Garriguet, 2009) was used to measure the quality of the foods and beverages consumed during the school day (9:00-14:00). The scores are on a scale of 0-100, where more than 80 points was considered a “high quality diet”, 50-80 points was “requiring improvement”, and less than 50 points was a “poor quality diet”. The following describes some of the characteristics of participants in the study:

• 25% aged 6-8 years old
• 43% aged 9-14 years old
• 33% aged 14-17 years old
• 51% were male, 49% were female 
• 9% classified as food insecure
• Approximately a third lived in low income household                          

The majority of participants were found to live in urban areas, have at least one household member who pursued some form of post secondary education, and identified as having European ethnicity. Simple descriptive statistics were used to calculate the average dietary contributions from school hours compared to the whole-day food consumption. Strengths of this study include the use of a nationally representative sample, and an adapted diet quality indicator (the Canadian Healthy Eating Index) to provide a comprehensive assessment of students’ dietary intakes. Limitations include the potential for inaccurate self-reporting, and the potential that days when the children were not actually at school, such as professional development days, were included in the study. 

 

Results

• Energy from food consumed at school was 33.6% of total daily energy on school days
• Relative to the mean energy contribution (about one-third of the day’s total caloric intake), foods consumed during school hours provided low contributions of protein, cholesterol, vitamin A, D, riboflavin, B6, B12, calcium, phosphorus, zinc, potassium, and milk products. In contrast, foods consumed during school hours provided higher contributions of minimally nutritious foods (e.g. chips, sugary beverages) (37% of the day’s total intake of these foods).
• Diet quality declined with age.
• There were some provincial variations in School-HEI scores. 
• No significant differences observed across any of the other demographic or socio-economic characteristics (sex, ethnicity, residential location, income, or food-security status). 

The findings suggest that foods consumed during school hours overall reduced the total day’s dietary quality because the nutrient densities of these foods were relatively low, especially for often under consumed nutrients by Canadian children (e.g. vitamin A, D, calcium and potassium). The average diet of Canadian children aged 6-17 “required improvement” (mean score= 50-80/100 points), which indicates an opportunity to change Canadian school dietary practices through national school food programs. School-based programs should focus on improving access to healthy foods, especially vegetables, whole fruit, whole grains, and milk.

 

Implications

Canadian school-based dietary strategies should aim to increase the availability of nutritious foods in order to increase intake of protein, vitamin A, vitamin D, calcium, and magnesium. Improving nutritional quality of school lunches for all children is key, but particularly among age groups at most risk for poor diet quality (i.e. 9-17 year olds).