Abstract
It is widely recognized that diet has an important effect on our health. A healthy and varied diet has the potential to reduce the risk of a number of non-communicable diseases. The traditional approach in nutrition epidemiology has focused on the relationship between disease and specific food items or nutrients. However, individual foods are usually not eaten in isolation, and data on how the intake of foods is combined and distributed across meals provide additional information about the food habits of a specific population. Such information will be useful when formulating food-based dietary guidelines and when tailoring interventions for healthy eating to a target population.
The main aim of the thesis was to study how different meals are associated with intakes of specific food groups and nutrients in a group of adult Norwegians. Moreover, we investigated how meal composition varied according to the participants’ background characteristics and according to meal-related factors such as meal eating location.
Data from the national dietary survey Norkost 3 were used to address these questions. In this survey, two telephone-administered 24-hour dietary recalls assessed dietary intake in 1787 men and women aged 18-70 years old. Meals were labeled by the participants as breakfast, lunch, dinner, supper/evening meal or snack. The collected meal-specific information included meal type, place of consumption, time of consumption and intake of foods and beverages at each meal.
The findings from the present thesis showed quite meal specific patterns for the intakes of fruits, vegetables, fish and whole grains, with some meals contributing substantially more to the intake than others. Hence, encouraging the intake of these dietary components from additional meal types, preferably replacing more energy-dense and nutrient-poor foods, may be a way of facilitating increased intakes and increased dietary quality in daily living. Snacks were found to contribute substantially to energy intake, and improved snack composition would contribute to an overall healthier diet. The location where meals were consumed appeared to be associated with the content of the meal, and some eating locations were associated with more favorable dietary intakes than others. This was observed both for dinners and snacks. Improvement of the quality of out-of-home foods will be a way of contributing to increasing the quality of the diet as a whole, in particular for high consumers of out-of-home foods. Finally, our results showed that the intakes of some food groups may be associated with the intakes of other food groups as well, and information about associated foods will be important both for developing public health guidelines and when studying associations between dietary factors and health outcomes.