First-year changes in mental health, lifestyle behaviors, and social support among international students at a Japanese university.

International students experience psychological distress due to cultural adjustment, loneliness, and limited social support. However, longitudinal evidence remains scarce in Japan, and comprehensive models incorporating lifestyle and social factors remain underexamined. This study investigated the changes in mental health symptoms, lifestyle behaviors, and social support during international students' first year after university enrollment. Furthermore, we examined longitudinal changes and their associations with academic year repetition. This study included 216 international students who enro