Healthy Diet is Central in the Network of Health Behaviors among Young Chinese Adults

Abstract Background Health behaviors established during young adulthood significantly shape the long-term risk of non-communicable diseases and mental health disorders. Although behaviors such as diet, physical activity, sleep, and substance use are often targeted individually, growing evidence suggests these behaviors function as an interconnected system. However, the organization of lifestyle behaviors at the system level, and which behaviors exert the greatest structural influence, remains poorly understood, particularly in non-Western populations. Purpose This study aimed to model the interdependence of lifestyle behaviors among university students in China and identify key behaviors with the greatest structural influence within a lifestyle network. Methods We analyzed cross-sectional survey data from 5,652 university students in China, assessing seven lifestyle behaviors (diet, physical activity, sleep quality, social engagement, green and blue space exposure, alcohol use, and tobacco use) as well as symptoms of anxiety and depression. A pairwise Markov random field model was used to construct a lifestyle network and identify behavioral clusters and influential behaviors. Network stability and subgroup invariance were evaluated using bootstrap and permutation procedures. Results Three stable behavioral clusters were identified: (1) a positive lifestyle cluster (diet, physical activity, social engagement, and environmental exposure), (2) a distress–sleep cluster (sleep problems, anxiety, and depression), and (3) a substance-use cluster (alcohol and tobacco use). Dietary behavior consistently emerged as the most central behavior in the network, with extensive connections to both behavioral and psychological domains. Physical activity played a more peripheral role. Strong coupling between sleep problems and emotional distress was observed, consistent with systems theories of mental health. Conclusions These findings support a systems-based framework for understanding health behaviors in young adulthood. Identifying structurally influential behaviors, particularly dietary behavior, can provide leverage points for targeted health interventions. The study highlights implications for public health policy and intervention design, particularly in non-Western university populations.