Nutrients and behaviour: research strategies for the investigation of taste characteristics, food preferences, hunger sensations and eating patterns in man.

Although, as described elsewhere in this report, the consumption of particular nutrients can modify behaviors that are not directly related to eating, it seems highly likely that the main function of nutrient-induced changes in neurotransmitter synthesis is to provide the brain with information about what has been eaten, which the brain can then utilize in deciding what to eat next. This chapter summarizes research strategies and techniques which have been used to assess the effects of drugs and diseases on appetite and food consumption, and which might also be useful in exploring the effects of particular nutrients. Crude measures of total food intake and of global hunger ratings are probably too insensitive to reveal the subtle effects of many nutrients. Some alternative procedures allow the assessment of particular aspects of feeding behaviour, (e.g. food or nutrient choice), and of the relationships between such behaviour and the individual's metabolic and physiological state, sensory functions, taste hedonics, and affective response to foods.