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

Our objective was to examine the prevalence of diet- and cancer-related psychosocial constructs in a population-based sample and their association with healthful diets. We administered a random digit dial survey on cancer-related risk behavior to 1972 adult Washington state residents. The psychosocial constructs were belief in an association between diet and cancer, knowledge of National Cancer Institute diet recommendations, knowledge of fat and fiber composition of foods, and perceived pressure to eat a healthful diet (norms). Diet measures were self-reported healthful diet changes over the previous 5 years, percent energy 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 composition consumed 2.1% less energy from fat than those with low knowledge (p for trend less than or equal to .001). Perceived norms were only weakly associated with fat and fiber intake. Intervention strategies targeting beliefs and knowledge may help people adopt more healthful diets. The findings on perceived norms suggest that extrinsic motivations (such as pressure from others) may be less effective than intrinsic motivations (such as beliefs) on promoting healthful behaviors.