In a group of 528 men, 30-54 years old, answers to various questions about dietary habits given in a questionnaire were compared to corresponding information given in a dietary history interview two years later. High concordance was found between the two methods for questions concerning types of foods most commonly used. For most food items, the mean intake according to the dietary recall corresponds well with intake reported in the questionnaire. For food items used every day in easily recorded units (slices of bread, cups of coffee, glasses of milk), the frequency questionnaire can be used to rank individuals according to consumption. For other food items, the concordance is less satisfactory.
In 2006, 20 % of adolescents aged 12-17 years used dietary supplements. Persons with high physical activity levels as well as those with high education levels consumed dietary supplements more often than others. Many supplement users used only one single-nutrient supplement. A similarly large proportion of users consumed one supplement with multiple nutrients. Most often supplements containing vitamin C, magnesium, B-vitamins, vitamin E and calcium were used.