The Role of Self-efficacy in Improving Dietary Behaviors for Reduction of Nutrition-related Cancers

Abstract

The effect of dietary self-efficacy on nutrient intake to reduce risk of cancer was studied in a prospective quasi- experimental design. It is estimated that an average of 35% of cancer deaths may be related to diet. Self-efficacy, a construct in social learning theory, may serve as a basis for the identification of methods to enhance healthy eating behaviors. Self-efficacy suggests that conviction in an ability to perform a skill determines which behaviors a person will engage in, how he or she will endure, and how much effort he or she will employ to achieve personal goals. Eat for Life, a nutrition and cancer prevention program, was developed to enhance one's self-efficacy by promoting positive outcome expectations, by providing clear dietary messages and encouraging participants to attempt small steps towards changes in eating habits. A self-efficacy questionaire was developed and pre-tested with a resulting coefficient reliability of 0.71±03 (baseline, pre-test, two post-tests). It measured three constructs: skills, integration of cognitive, personal and skill beliefs, and confidence. Subjects (n=82) were recruited from promotional fliers and media coverage and randomized into four groups. They participated in a three part educational series. Each program session was designed to build upon the skills and knowledge of the preceding class. Prior to the intervention and at one week and six months post-intervention subjects completed four day food diaries and self-efficacy questionnaires. Self-efficacy increased from the pre-test to both post-tests 17% (p<05). There were significant changes in dietary intake; a decrease in percentage of calories from fat (12%), and fat intake (12%). Fiber intake improved 24% (p<05) and servings of fruit 45% (p<01).At the second posttest, our study group's dietary patterns were significantly healthier than their national counterparts. The findings of this study are supportive of the hypothesis that dietary self-efficacy improves as a result of the hands-on intervention based on behavioral theory.