Abstract
Changing individuals' health behaviour seems to be the key to solving many of the world's health problems. Although there is a multitude of potential influences, many interventions to improve health seek to change intrinsic psychological determinants of health behaviour. To date, most attention has been paid to cognitions, such as attitudes and beliefs, and a number of social cognition models (SCM) are in current use. SCM all describe cognitions as determinants of behaviour, thereby implying that changes in cognitions will lead to changes in behaviour. Although SCM are widely used to predict a range of health behaviours, they are associated with a number of important limitations, including poor levels of predictive power, particularly in relation to eating behaviour, and limited guidance about the operationalisation of theoretical constructs. These limitations may explain why very few interventions to change behaviour are explicitly theory-based, despite the widely-held view that having a clear theoretical underpinning will improve effectiveness. Ultimately, advances in understanding and changing health behaviour will come about only if psychological theory and practice are integrated. The recently-published taxonomy of behaviour-change techniques used in interventions is a good example of integrated research, but more work of this type is essential and will require respectful collaboration between researchers and practitioners working from a range of different disciplines such as health psychology, public health nutrition and health promotion.