Dietary Adherence, Self-Efficacy, and Health Behavior Change of WASHOKU-Modified DASH Diet: A Sub-analysis of the DASH-JUMP Study

ABSTRACT: BACKGROUND: We previously reported the nutritional characteristics and effects of the DASH-JUMP diet, which is a WASHOKU-modified DASH diet, in Japanese participants with untreated high-normal blood pressure or stage 1 hypertension. The dietary adherence of the DASH diet in Japanese participants has never been evaluated before. OBJECTIVE: We aimed to assess the relationships between dietary adherence, self-efficacy, and health behavior change among study participants who received the DASH-JUMP diet by home delivery. METHODS: Participants were treated with the DASH-JUMP diet for 2 months and consumed their usual diets for the next 4 months. We conducted surveys using the stage of behavior change model questionnaire and the modified perceived health competence scale Japanese version questionnaire at baseline and 1, 2, 3, and 6 months to assess dietary adherence. RESULTS: Forty-three participants (25 men, 18 women; mean age 53.6 ± 8.2 years) returned completed questionnaires, which we analyzed. Health behavior change was motivated by previous behavioral changes and improved biomarkers. The improvement and maintenance of self-efficacy were deeply related to health behavior change and previous self-efficacy. The experience of the DASH-JUMP study for participants included three processes to improve lifestyle habits: Phase 1, reflecting on previous lifestyle habits; Phase 2, learning through new experiences and the acquisition of knowledge; and Phase 3, desiring to maintain their own health. CONCLUSION: It indicated that the DASH-JUMP diet significantly increased self-efficacy and promoted health behavior change.