The hidden carbon costs of aging: How household dependency burden shapes emissions in China

Rapid population aging is reshaping household dependency structures with profound implications for consumption behavior and carbon emission trajectories. However, the pathways through which dependency burdens affect household carbon footprints remain insufficiently understood, limiting both theoretical insight and policy responses to demographic transitions. Using microdata from the China Family Panel Studies (CFPS), this study examines how household dependency ratios influence carbon emissions, while accounting for heterogeneity and underlying mechanisms. We find that higher dependency ratios significantly increase household carbon emissions, with child dependency exerting a stronger effect than elderly dependency. These effects are concentrated in carbon-intensive domains such as housing, private transport, and food. Heterogeneity analysis shows that the impact is more pronounced among low-income and less healthy households, as well as in urban areas and western regions, reflecting uneven vulnerability to demographic pressures. Mechanism analysis indicates that dependency burdens raise the propensity to consume and reallocate spending toward subsistence-oriented categories, such as food and housing, that are relatively more carbon-intensive. Concurrently, this adjustment reduces discretionary spending on leisure and culture, which is likely to substantially compromise household well-being, particularly in its non-material dimensions. The findings reveal a potential demographic sustainability dilemma, characterized by concurrent increases in emissions and declines in well-being. This study thereby provides critical insights into how demographic transition shapes household carbon footprints, highlighting the complex sustainability challenges that aging societies must confront.