The current literature on the self-regulatory determinants of health behaviours primarily focuses on motivational variables. The health belief model (Hochbaum, 1958; Rosenstock, 1966, 1974) lists general health values, specific beliefs about vulnerability to a particular disorder, and beliefs about the consequences of this disorder. For example, a person may consider changing her diet to include low cholesterol foods, if she values health, feels personally threatened by the possibility of heart disease and believes that the threat of heart disease is severe. Whether or not a health threat leads to the actual implementation of the respective health behaviours, however, further depends on whether a person believes that these behaviours will reduce the experienced threat. This in turn is determined by both the belief that the specific measure can be effective and the belief that the benefits of the health behaviour exceed its costs.