Previous studies have reported that older people’s social participation has positive effects on their health. However, some studies showed that the impacts of social participation on health differ by gender. We sought to examine whether the effects of social participation on mental health differ for men and women in a Japanese population. We also examined the moderating influence of social position within the organization as well as urban/rural locality.

Although studies have suggested that community social capital contributes to narrow income-based inequality in depression, the impacts may depend on its components. Our multilevel cross-sectional analysis of data from 42,208 men and 45,448 women aged 65 years or older living in 565 school districts in Japan found that higher community-level civic participation (i.e., average levels of group participation in the community) was positively associated with the prevalence of depressive symptoms among the low-income groups, independent of individual levels of group participation. Two other social capital components (cohesion and reciprocity) did not significantly alter the association between income and depressive symptoms.

Previous studies have reported that spousal non-smoking has a spillover effect on the partner’s cessation. However, discussion is lacking on the factors modifying that association. We examined whether the spillover effect of spousal non-smoking was associated with the couple’s educational attainment. We used paired marital data from the Japanese Study on Stratification, Health, Income, and Neighborhood (J-SHINE), which targeted residents aged 25–50 years in four Japanese municipalities. We selected a spouse smoker at the time of marriage (target respondent), and set his/her smoking status change (continued or quit smoking after marriage) as an outcome, regressed on the counterpart’s smoking status (continued smoking or non-smoking) and combinations of each couple’s educational attainment as explanatory variables using log-binomial regression models (n =1001 targets; 708 men and 293 women). Regression results showed that a counterpart who previously quit smoking or was a never-smoker was associated with the target male spouse’s subsequent cessation. However, for women, the association between husband’s non-smoking and their own cessation was significant only for couples in which both spouses were highly educated. Our findings suggest that a spouse’s smoking status is important for smoking cessation interventions in men. For women, however, a couple’s combined educational attainment may matter in the interventions.

Community social networks positively affect older adults' dietary behavior, but the underlying mechanisms remain uncertain. This study investigated if the relationship between community social networks and dietary behavior is mediated by social participation, and whether the influence of community social networks differs across sociodemographic groups. We conducted a cross-lagged panel mediation analysis employing nonlinear structural equation modeling using panel data from the Japan Gerontological Evaluation Study (JAGES), a longitudinal study of Japanese older adults in 2010, 2013, and 2016, which included 11,347 men and 14,105 women aged over 65. Monodirectional relationships in community social networks, individual social participation, and fruit/vegetable intake were examined. Community social networks were associated with social participation regardless of sociodemographic conditions. Individual social participation was in turn, positively associated with fruit/vegetable intake, with this association being stronger among those living alone. Analyses further showed that individuals' social participation positively mediated the relationship between community social networks and fruit/vegetable intake. For both genders, the mediating effects were stronger among people living alone than in those living with someone. However, community networks could also directly and negatively affect fruit/vegetable intake among men who live alone unless they participated in community activities. Community social networks may promote social participation, thereby facilitating healthier dietary behavior regardless of sociodemographic status. Social participation in turn may positively contribute to the dietary health of people living alone. Community-based interventions to encourage people living alone to participate in social activities may help reduce inequality in dietary behavior related to cohabitation status.

Parents with less formal education are more likely to smoke indoors, causing socioeconomic disparity in children’s exposure to second-hand smoke. However, little is known about the roles of social factors in the socioeconomic gradients of indoor smoking. We tested the potential mediating role of perceived smoking norms on the associations between education and indoor smoking among parents who smoke. In this cross-sectional study, 822 smoking fathers and 823 smoking mothers, who lived with young children and were members of a Japanese online survey panel, participated. Structural equation modelling tested the mediating effects of perceived descriptive and subjective norms on the association between education and indoor smoking. Perceived pro-smoking norms, which were more prevalent among less-educated parents, mediated the association between education and indoor smoking. Household smoking status and worksite smoking ban also mediated this association via perceived norms, but only for fathers. Perceived descriptive norms explained 28.5% of the association for fathers and 37.6% for mothers; the corresponding percentages for perceived subjective norms were 9.8% and 26.6%, respectively. Perceived smoking norms, household smoking status, and a worksite smoking ban could be vital targets of a strategy aimed at reducing the socioeconomic disparity in parental home smoking behaviours.

Mobility management is a transportation policy aiming to change travel behavior from car use to sustainable transportation modes while increasing people’s physical activity. Providing pedometers and visualizing step counts, popular interventions in public health practice, may constitute a mobility management program. However, the ease of modal shifts and changeability of walking habits differ across neighborhood environments. Using questionnaire data from 2023 middle-aged and older participants from Yokohama, Japan, in May 2017, this study examined (1) the relationship between the physical and social environments of Yokohama Walking Point Program participants who volunteered to use free pedometers and their modal shifts from cars to walking and public transport, and (2) whether participants’ modal shifts were associated with increases in step counts. Multivariate categorical regression analyses identified the frequency of greetings and conversations with neighbors as well as health motivation as important explanatory variables in both analyses. Participants living in neighborhoods far from railway stations and in neighborhoods with a high bus stop density tended to shift to walking and public transport, a modal shift that was highly associated with increased step counts. These results suggest that mobility management should be promoted in collaboration with public health and city planning professionals.