Social asymmetry and physical health in the United States and Japan.

OBJECTIVE

Social relationships are increasingly recognized as crucial determinants of health, but cultural variations in the health implications of social disconnection remain understudied. This study examines how nationality, reflecting cultural differences in social norms, moderates the relationship between social asymmetry and physical health in Japanese and U.S. adults. We hypothesized that the association between greater social asymmetry and poorer health would be attenuated in Japan compared to the United States.

METHOD

The sample comprised adults aged 23-84 years from Japan (N = 1,027) and the United States (N = 6,650) participating in the Midlife in Japan and Midlife in the United States longitudinal studies. Social asymmetry was quantified as the residual score from regressing loneliness on social isolation, with positive residuals indicating higher loneliness than expected based on isolation levels. Physical health was a latent variable indicated by chronic conditions, symptoms, activities of daily living, and physical activity. Structural equation modeling examined the moderating effect of nationality on the social asymmetry-health link.

RESULTS

Across both cultural contexts, greater social asymmetry (i.e., higher loneliness than predicted by isolation) was associated with worse physical health. However, as hypothesized, this relationship was significantly weaker in Japan compared to the United States, highlighting the role of cultural context in shaping the health implications of discrepant social experiences.

CONCLUSIONS

Findings contribute to understanding cultural variations in the health consequences of social disconnection and emphasize the need to consider sociocultural factors when examining social determinants of health across diverse populations. (PsycInfo Database Record (c) 2025 APA, all rights reserved).