Diet quality of Montreal area adults needs improvement

Nutrition Research Newsletter, Sept, 2005 by Bryna Shatenstein, Sylvie Nadon, Catherine Godin, Guylaine Ferland

Comprehensive, regular, country-wide dietary monitoring is not a steady feature of health surveys in Canada due to time and budget constraints. Summary nutrition indicators, in conjunction with a regular nutrition surveillance program, could be useful for rapid screening of diet quality, thereby contributing to effective, targeted nutrition interventions. To encourage regular population diet monitoring in Canada, a group of Canadian researchers developed and assessed the relative validity of a population-based food frequency questionnaire (FFQ) to assess usual diet in Quebecers. The US Department of Agriculture Health Eating Index (HEI), which has a maximum score of 100, was also adapted to Canadian age- and sex-specific dietary recommendations, validated and programmed to score the FFQ for overall diet quality.

The 73-item FFQ was pretested, pilot tested and administered by mail to a random sample of 248 adults aged 18 years to 82 years in the Montreal area who were recruited by random digit dialing. A subgroup of 94 people provided four nonconsecutive one-day food records for validation of the FFQ.

The FFQ estimated daily energy intakes as 2,216 kcal among men and 1,785 kcal in women. Median macronutrient consumption was similar in both males and females at 17% protein, 34% to 35% fat, and 48% to 49% carbohydrates, but differed by age group in women. Most mean and median nutrient intakes met or exceeded recommended intake levels for both men and women except for vitamin A among men, and calcium for both men and women. Mean Canadian HEI was higher in women (74.9) than men (70.3). Women's scores showed they met recommendations for fruit and vegetable intakes, cholesterol and sodium better than men, while men fared better at meeting recommended fat intake levels. The HEI calculated that a relatively small proportion of the sample, approximately 20% of men and 29% of women, had a "good" diet defined as a score > 80.

The Canadian HEI adequately discriminates overall diet quality based on dietary data estimated from the FFQ. Examination of subscores within and between quartiles may best reveal which food groups require attention to improve diet quality, providing valuation information for teaching and planning. Future studies should test diet quality indicators in populations recruited to reflect greater dietary diversity and reporting ability, and include members of disadvantaged groups to provide a broader set of behaviors that could shed light on factors influencing diet quality.

Bryna Shatenstein, Sylvie Nadon, Catherine Godin, and Guylaine Ferland. Diet quality of Montreal-area adults needs improvement: Estimates from a self-administered food frequency questionnaire furnishing a dietary indicator score. JADA; 105:1251-1260 (August 2005) [Address correspondence to: Bryna Shatenstein, PhD, Centre de Recherche, Insitut Universitaire de Heriatrie de Montreal, 4565 Queen Mary, Montreal, QC Canada H3W 1W5. E-mail: bryna.shatenstein@umontreal.ca]