DIET CANCER-RELATED BELIEFS, KNOWLEDGE, NORMS, AND THEIR RELATIONSHIPTO HEALTHFUL DIETS

Our objective was to examine the prevalence of diet- and cancer-relate d psychosocial constructs in a population-based sample and their assoc iation with healthful diets. We administered a random digit dial surve y on cancer-related risk behavior to 1972 adult Washington state resid ents. The psychosocial constructs were belief in an association betwee n diet and cancer, knowledge of National Cancer Institute diet recomme ndations, knowledge of fat and fiber composition of foods, and perceiv ed pressure to eat a healthful diet (norms). Diet measures were self-r eported healthful diet changes over the previous 5 years, percent ener gy from fat, and dietary fiber. Age and education were significantly ( p less than or equal to .001) related to the constructs. Older adults (60+) had the lowest levels of belief knowledge, and perceived norms. Participants with strong beliefs in a diet-cancer connection consumed 1.1 grams more fiber than those with no belief (p for trend less than or equal to .001), and participants with excellent knowledge of food c omposition consumed 2.1% less energy from fat than those with low know ledge (p for trend less than or equal to .001). Perceived norms were o nly weakly associated with fat and fiber intake. Intervention strategi es targeting beliefs and knowledge may help people adopt more healthfu l diets. The findings on perceived norms suggest that extrinsic motiva tions (such as pressure from others) may be less effective than intrin sic motivations (such as beliefs) on promoting healthful behaviors.