Do beliefs, knowledge, and perceived norms about diet and cancer predict dietary change?
R E Patterson, A R Kristal and E White Cancer Prevention Research Program, Fred Hutchinson Cancer Research Center, Seattle, Wash 98104, USA. OBJECTIVES: We hypothesized that belief in an association between diet and cancer, knowledge of dietary recommendations and food composition, and perceived norms would predict healthful dietary changes. METHODS: Data are from a population-based sample of Washington State residents (n = 607). Psychosocial constructs measured at baseline (1989/90) were used to predict changes in dietary practices, fat intake, fiber intake, and weight over 3 years. RESULTS: Adults who strongly believed in a diet-cancer connection decreased the percentage of energy consumed from fat by 1.20 percentage points and increased fiber intake by 0.69 g, compared with decreases of 0.21 percentage points and 0.57 g among those with no belief (P < .05). Adults with knowledge of the National Cancer Institute fat and fiber goals decreased their percentage of energy from fat by 1.7