Foods are complex mixtures of compounds characterised by wide variation in composition and nutritional value. If a GM food or food component which, on the basis of the background information, cannot be shown to be substantially equivalent to its traditional counterpart, further nutritional information may be required depending on its anticipated intake and nutritional significance.

The background information available on the GM food or ingredient will include details of its nutrient composition taking into account agricultural production, storage, industrial processing and home cooking. The influence of these factors should be carefully considered since there have been occasions in the past when minor process changes have had serious nutritional consequences.

Nutritional evaluation

The nutritional evaluation of the GM food or food ingredient depends on the consumption by the consumer. It is necessary to establish a normal and maximum probable level of consumption, which have to be refined if the dietary pattern changes. The nutritional evaluation has to take into consideration three elements:

• Composition of the food itself
• Importance of the food in the diet, and
• Food(s) in which it will be used

Bioavailability

Bioavailability studies are necessary for the main nutrients, protein, lipids and carbohydrate, as well as for vitamins and minerals. The bioavailability testing of nutrients is focussing on the availability of the components in order to assure that the GM food does not interfere with the metabolism, including digestibility and absorption.