Sociodemographic differences in dietary habits described by food frequency questions--results from Denmark

To investigate whether a modest number of food frequency questions are sufficient to describe sociodemographic differences in dietary habits, and to identify sociodemographic characteristics of subjects adhering to food-based dietary guidelines operationalised in a "healthy-diet index".

Cross-sectional population survey.

A total of 480 men, 515 women, aged 15-90 y. Random sample of private telephone numbers drawn from regional telephone records, geographically stratified. Participation rate 62%.

Computer-assisted telephone interviews, including six food frequency questions, a question on type of fat spreads used on bread, questions on seven sociodemographic variables.

The summary of the healthy-diet index showed that the subjects who adhered to food-based dietary guidelines (top quintile) compared to those who did not (bottom quintile) were most often women (odds ratio (OR)=6.07; confidence interval (CI): 3.91-9.43, women vs men), of older age (OR=9.72; CI: 3.02-31.31, old age vs young), highly educated (OR=3.69; CI: 1.53-8.92, high education vs low) and living in multiperson households including children (OR=4.66; CI: 2.47-8.80, multiperson household vs single household). The results also showed that gender difference in dietary habits is associated with other sociodemographic variables.

The selected food frequency questions proved sufficient to describe sociodemographic differences in dietary habits, and this method may be a valuable supplement to traditional quantitative dietary surveys in monitoring sociodemographic changes in eating patterns. The results also underline the influence of sociodemographic status on dietary habits.

The Danish Nutrition Council funded the study.