OBJECTIVES: Despite the increasing importance of patient-centered perspectives, the impact of weight change on the health-related quality of life (HRQL) has remained unclear. This work aims to investigate this longitudinal relationship. METHODS: Data was collected from a population-based cohort study of 3,080 Germans. Anthropometrics and HRQL were assessed at baseline and after a 7-year follow-up period. Using linear regression the average change in HRQL scores was calculated among 5 mutually exclusive weight change groups. Multilevel growth modeling was conducted to differentiate between interpersonal (cross-sectional) and intrapersonal (longitudinal) associations between body mass index (BMI)/BMI change and HRQL. RESULTS: Heavy weight gain (≥10 % body weight) was associated with impairments in physical health among women (-2.82 points, CI: -4.29, -1.34) and obese men (-4.33 points, CI: -7.62, -1.04) and with improvements in mental health among women (+3.20 points, CI: +1.37, +5.02). Results from the multilevel models were consistent, showing negative associations between BMI change and physical health, positive associations between BMI change and mental health and a high degree of similarity between interpersonal and intrapersonal associations. CONCLUSIONS: Weight gain leads to clinically relevant impairments in physical health. More research is needed to clarify the antipodal effects of weight change on physical and mental health components.