Statistics Canada
Symbol of the Government of Canada

Warning View the most recent version.

Archived Content

Information identified as archived is provided for reference, research or recordkeeping purposes. It is not subject to the Government of Canada Web Standards and has not been altered or updated since it was archived. Please "contact us" to request a format other than those available.

The data

The 2004 Canadian Community Health Survey—Nutrition collected information about the food and nutrient intake of the household population at the national and provincial levels.  Information about the use of vitamin and mineral supplements was also collected.  The survey excluded members of the regular Canadian Forces; residents of the three territories, Indian reserves, institutions and some remote areas; and all residents (military and civilian) of Canadian Forces bases. Detailed descriptions of the survey design, sample and interview procedures are available in a published report.6

A total of 35,107 people responded to an initial 24-hour dietary recall, and a subsample of 10,786 took part in a second dietary recall three to ten days later. The response rates were 76.5% and 72.8%, respectively.

Canadians’ intake of food and nutrients was estimated with a 24-hour dietary recall. To help respondents remember what and how much they ate and drank the previous day, interviewers used the automated multiple-pass method (AMPM),7,8 which consists of five steps:
• a quick list (respondents reported all foods and beverages consumed);
• questions about specific food categories and frequently forgotten foods;
• questions about the time and occasion of consumption;
• questions seeking more detail about the foods and beverages and the quantities consumed; and
• a final review.

Questions about vitamin and mineral supplements pertained to consumption frequency in the last 30 days.  Respondents were asked the number of days that they had taken supplements and the average quantity consumed.  More information about these derived variables is available in the survey documentation.9

The nutrient content of the food that respondents reported was derived from Health Canada’s Canadian Nutrient File (Supplement 2001b).10 The composition of supplements was taken from the Drug Product Database (DPD)11 for September 2003 in the case of drug identification numbers listed at the time of collection, and for spring 2005 if the drug identification numbers were missing or incorrect.

This study examined data for 34,386 people aged 1 or older, 10,591 of whom responded to the second 24-hour dietary recall.  Children younger than 1 year (288), pregnant (175) and nursing (92) women, breastfed children (104), and respondents with no dietary intake (16) or invalid dietary intake (45) were excluded from the analysis.

SIDE (Software for Intake Distribution Estimation)12,13 was used to determine the usual distribution, and in particular, the percentage of the population with inadequate vitamin C intake (below the estimated average requirement). To compensate for within-individual intake variability, the daily distribution of the intake of a nutrient was adjusted with the second dietary recall.  Because the vitamin C requirements of children, teens, adults, males, females and smokers differ, intake is expressed in relation to the requirements of the group to which the respondent belongs. Hence, the percentage of the population with inadequate vitamin C intake is the proportion for which the ratio is less than 1.

The distribution of vitamin C intake that includes both dietary sources and supplements was determined by combining estimated intake from food alone for the respondents who do not take supplements and the total estimate (intake from food plus average daily intake from supplements) for respondents who take supplements. Details about the methods are available in an accompanying article.2

To account for the complex design of the Canadian Community Health Survey, the bootstrap method14-16 was used to estimate standard errors, coefficients of variation and confidence intervals. The statistical significance level was set at 0.05.

Fruit and vegetable consumption frequency is not based on the 24-hour dietary recall; it refers to the reported number of times per day that respondents ate fruit and vegetables, not the quantities that they consumed.

Household income is income from all sources in the previous 12 months. The ratio of total household income to the low-income cut-off for the relevant household size and community size was calculated for each household. The ratios were adjusted by dividing them by the highest ratio for all Canadian Community Health Survey respondents. The adjusted ratios were grouped into quintiles, the first quintile containing the lowest incomes, and the fifth, the highest.

Highest level of household education refers to the highest level of educational attainment of at least one household member.

Smoker refers to people who reported that they smoked daily or occasionally. Level of physical activity (inactive, moderately active, active) is based on average daily energy expenditure derived from the reported frequency and duration of all leisure-time physical activity in the three months before the interview and each activity’s metabolic energy expenditure (non-leisure activity is not included). These two variables are not available for respondents younger than 12.