[Association of vegetable intake with dietary behaviors, attitudes, knowledge, and social support among the middle-aged Japanese population].

Objectives Increasing vegetable consumption is one of the health objectives of "Healthy Japan 21" (2nd phase). To ensure this goal is met, the various factors related to vegetable consumption must first be clarified. Thus, this study considered vegetable consumption, dietary behaviors, attitudes, knowledge, and social support among middle-aged Japanese subjects.Method Data (2 days of maintaining a food diary and a questionnaire) of 384 respondents aged 30-59 years from the 2011 Saitama Prefectural Health and Nutrition Survey (men: 165, women: 219) were used. Their average volume of vegetable consumption was 250.2 g/day (standard deviation: 119.8), which was significantly lower than the 350 g/day goal of "Healthy Japan 21" (2nd phase); therefore, the threshold for this study was set at 300 g/day. For logistic regression analysis, vegetable consumption greater or lower than 300 g/day were defined as dependent variables; social support, attitudes, knowledge, and dietary behaviors as independent variables; and age, household composition, and household income were adjusted.Results The adjusted odds ratio (AOR) was significantly higher for those whose vegetable consumption was over 300 g/day. Dietary behaviors including an average of 2 or more meals per day including grain, vegetable, fish, and meat dishes and the analysis of subjects' food records revealed an AOR of 2.52 and a 95% confidence interval (CI) of 1.18-5.39 for men who had 2 or more meals per day. For women, the AOR was 4.06, and the 95% CI was 2.18-7.53. Significant relationships were observed among the following items in male respondents: attitude category: "self-efficacy in consuming 5 or more vegetable dishes per day" (AOR was 2.74, 95% CI was 1.30-5.79); knowledge category: "obesity prevention effectiveness" (AOR was 3.48, 95% CI was 1.24-9.78); and social support category: "support for good health and dietary life from family and surroundings" (AOR was 4.46, 95% CI was 1.47-13.54). Significant relationships were observed among the following items in female respondents: dietary behaviors category: "frequency of cooking meals" (AOR was 2.83, 95% CI was 1.02-7.87); and knowledge category: "being able to grasp the appropriate volumes and balance of foods when preparing meals for self" (AOR was 2.44, 95% CI was 1.30-4.56).Conclusions These results suggest that to increase middle-aged people's vegetable consumption, promoting adequately healthy meals is more important than both the dissemination of knowledge regarding the target vegetable quantity and enhancing of only vegetable consumption.