Increasing vegetable intake is recommended for promoting health in communities. This study investigated the effects of nutrition education on vegetable intake and the factors associated with changes in vegetable intake among residents of Okinawa. Subjects (n=1,345; mean [±SD] age 56.8±14.6 years; 40.5% male) were recruited from among local residents participating in the Yui Kenko Project. Subjects completed the brief-type self-administered diet history questionnaire (BDHQ) and questionnaires on socioeconomic demographics and social capital. Subjects were divided into 2 groups according to residential area, namely south Okinawa (n=679), where local health promotion activities have been undertaken since the early 2000s, and central Okinawa (n=666). Survey results were fed back to each subject, and health lectures were then conducted at local community centers. After 1 year, the BDHQ was repeated to investigate changes in vegetable and nutritional parameters. After the intervention, residents of south Okinawa increased their crude and energy-adjusted vegetable intake (P<0.05), whereas residents of central Okinawa showed decreased vegetable intake (P<0.05). Univariable and multivariable regression models indicated that, in south Okinawa, participation in local health promotion activities and agreement with general trust were positively correlated with changes in energy-adjusted vegetable intake, whereas in central Okinawa no correlations were observed. The status of social capital should be taken into account when implementing initiatives to increase vegetable intake in communities.