["Journal of Research on Adolescence, Volume 36, Issue 2, June 2026. ", "\nAbstract\nChild maltreatment is a significant risk factor for mental and metabolic health, with negative effects that can persist into adulthood. Using data from a U.S.‐nationwide study, the National Longitudinal Study of Adolescent to Adult Health (Add Health), this study examined the associations between child maltreatment, specifically childhood threat (i.e., harm or threat of harm) and deprivation (i.e., absence of expected environmental inputs), and young adult mental (i.e., depressive symptoms) and metabolic health (i.e., metabolic risk). The moderating effect of social support was also examined, focusing on both quality of different types of support (i.e., from teachers, friends, and other adults) and variety of support sources. Results showed that young adults who experienced more threat during childhood exhibited higher levels of depressive symptoms in young adulthood, and those exposed to more deprivation reported elevated levels of metabolic risk. This study also highlighted the protective‐stabilizing role of quality of teacher support in buffering the impact of deprivation on depressive symptoms, and the protective‐stabilizing role of high‐quality other adult support in the link between childhood deprivation and metabolic risk, such that the benefits of social support remained stable across increasing levels of deprivation. Additionally, the variety of social support showed a protective‐reactive pattern in moderating the link between deprivation and metabolic risk, wherein the benefits of variety of social support were released under low deprivation but not high deprivation conditions for metabolic risk. These findings underscore the importance of eliminating child maltreatment experiences and highlight potential interventions, such as enhancing teacher‐student relationships and broadening adolescents' access to diverse support networks, to buffer the long‐term mental and metabolic health consequences associated with early experiences of threat and deprivation.\n"]