The Psychobiology of Hunger – A Scientific Perspective

From a scientific perspective, hunger can be regarded as an identifiable conscious sensation which can be distinguished from other conscious states (e.g., pain, fear). The hunger state can be measured and is a marker of the existence of underlying biological processes. Measured hunger is functional and is normally associated with the act of eating. However, the conscious state of hunger, although driven physiologically, is not exclusively determined by biology; there is an environmental influence that can modulate its intensity and periodicity, and cultural factors that shape the appropriateness of the expression of hunger. Within a psychobiological framework, hunger can be considered as the expression of a ‘need state’ which mediates between biological requirements and environmental (nutritional) satisfaction. Our empirical studies show that hunger is clearly associated with biological signals (e.g., resting metabolic rate and some gastrointestinal peptides) and is central to the relationship between energy expenditure and energy intake.