Objectives The general educational development (GED) diploma is intended to be equivalent to a high school (HS) credential; however, recent evidence finds that GED recipients have worse health than HS graduates. This study aims to explain the health disadvantage, focusing on three domains: noncognitive skills, health behaviors, and economic factors. Methods We analyze data on 3,119 HS graduates and GED recipients in the NLSY79 who reported their health status at the age of 40. Logistic and ordinal regression models examine whether the three domains account for the GED health disadvantage. Results The GED health disadvantage was jointly explained by lower noncognitive skills, unhealthy behaviors, and adverse economic circumstances, with the latter being particularly important. Conclusions A multipronged approach may be necessary to reduce the GED health disadvantage, including improving noncognitive skills during K–12 education, expanding opportunities for employment and living wage for low‐skill workers, and continued focus on improving health behaviors.