Variation in nutrient content in foods
The nutrient values in the Food Composition Table are representative levels of nutrient content, not exact values.
There always will be some variation in the content of nutrients in the same type of food. In vegetarian foods, the nutrient content can vary with variety, growing conditions and degree of ripening. The nutritional content of animal foods may vary with race, feeding and slaughter age. The content of fish and shellfish also varies between where and when during the year they are caught, and what they have eaten. Conditions during storage, transport, industrial processing and/or preparation in the household may affect the nutritional content of the food. Differences in analytical methods or calculation methods may also result in minor differences.
Through the preparation of food, the nutrient content may change. For example, roasted meat or fish will have a higher content of energy-yielding nutrients than the raw products, since some of the water evaporates during roasting. The content of vitamins and minerals may be lower after heat treatment of foods.
Edible portion
All table values apply to 100 g edible food. That is, the nutrient content after the skin, bones etc. has been removed.
Missing or unknown values
When the nutrient value is 0, it may either be that the nutrient is not present in the food or that the amount is so small that the nutrient cannot be detected through analysis.
Database system
The Norwegian Food Safety Authority uses the food database system FoodCASE (foodcase.org) an international database system for working with food data, based on the coding and compilation methodology of the European food data network EuroFIR (eurofir.org)
Use of Recommended Daily Intakes in the Norwegian Food Composition Table
The Norwegian Food Composition Table shows how much a food contributes to the recommended daily intake of vitamins and minerals. The values for the recommended daily intake are from the Norwegian Directorate of Health's reference values for nutrient intake (helsedirektoratet.no). In the Food Composition Table, the recommended intake includes both the recommended intake (RI) and the adequate intake (AI).