Does social participation foster social support among the older population in Japan? A three-year follow-up study from the Japan gerontological evaluation study

•Whether social participation has generated new, healthier social support is unclear.•We prospectively examined whether social participation fosters social support.•Social support was dose-responsive to the number of types of social participation.•Social support was fostered by participating in some type of group at any frequency.•Support to encourage social participation may be effective to enhance social support.