Forming a background to this research are the well-established links between stress and disease on the one hand, and dietary composition and disease on the other. Associations between stressful life events and weight gain, and between perceived stress and serum cholesterol, have been observed in the general population. In addition, studies of obese and dieting populations have revealed that the eating behaviour of some individuals is affected by stress. This raises the possibility that one of the mechanisms through which stress might influence health is via an effect on food intake. Stress is widely believed to influence eating behaviour, but the evidence derives largely from clinical observation and anecdotal report. In the small number of studies that have been carried out in this area, the results have been inconclusive. These converging lines of evidence suggest that the influence of stress on food intake and, more specifically, food choice, is well worth studying. A link between stress and fat intake, for example, would be of considerable importance both for understanding the psychobiology of food intake, and for interventions to reduce the prevalence of diseases of Western society such as obesity, diabetes and coronary heart disease. This research aimed to investigate the prevalence and nature of stress-induced changes in eating within the general population, using a variety of methodologies. An initial questionnaire study examined the self reported prevalence of stress induced changes in a population of undergraduate students, looking at the effect of stress on overall intake and also changes in preference for specific foods. It also investigated the possibility that individuals prone to stress-induced changes in eating may be defined by parameters such as gender or dieting status. Results indicated that the majority of the sample believed their eating to be influenced in some way by stress, with reports of increased eating and decreased eating occurring with approximately equal frequencies, although dieters were more likely to report eating more when stressed. Foods reportedly preferred during stress were predominantly snack foods, this was in agreement with reported increases in snacking with stress among the majority of respondents, and was true of hyperphagics and hypophagics alike. Thus the 'dietary role' of a food appeared to be the dominant influence over stress-induced preference in this sample. The stress-eating relationship was examined in the laboratory by manipulating stress and assessing food intake and selection during a single meal. Increased intake of sweet, fatty foods was seen by stressed subjects who were emotional eaters. This group also ate a meal that was highly energy dense compared with unstressed emotional eaters. A longitudinal study of 6 months' duration investigated the stress-eating relationship in the 'real world' environment, by assessing dietary change in department store workers over periods of varying work load. The findings provided tentative support for a general hyperphagic effect of work stress; dietary restraint and emotional eating were not found to influence the stress-eating relationship in this case. Finally structured interviews in a small sample of self-identified 'stress-eaters' provided descriptive data on the nature of the stress-eating relationship. Interviewees consistently referred to their stress-eating tendencies as providing some sort of emotional nourishment rather than fulfilling any increased physiological need for food. The findings from this thesis suggest that during certain types of stress, many individuals are prone to increased snack consumption. Implications are discussed
