The relationship between knowledge of cardiovascular dietary risk and food shopping behaviors

A 44-item knowledge and attitude questionnaire was administered to 176 randomly selected shoppers to determine their cardiovascular and nutrition knowledge and attitude toward the diet-heart relationship. An analysis of descriptive sales slips issued by the supermarket determined food purchasing behavior. Food items purchased were categorized according to their polyunsaturated-saturated (P/S) ratio less than 1 (PS0), P/S ratio greater than 1 (PS1), and high cholesterol (greater than 100 mg per serving) (HCHO). We also categorized purchases by cholesterol content per serving: high, moderate, low, and very low levels. We observed a significant (r = -.25, P = .0008) negative correlation between purchasing behavior of PS0 and knowledge. A partial correlation revealed a similar association when controlling for income (r = -.26, P = .0002), age (r = -.26, P = .0005) and education (r = -.22, P = .0038). Correlation for whites was significant and negative (r = -.29, P = .0003) and for blacks nonsignificant and positive (r = .02, P = .9069). Regression analysis found a significant negative slope (b = -.57, P = .0001) of PS0 on knowledge, a marginally significant positive slope (b = -.21, P = .0527) of PS1 on knowledge, and a significant negative slope (b = -.86, P = .0171) of HCHO on education. The interaction of race and knowledge was significant for PS0 (P = .0005).