This dataset includes the supplementary materials of the publication: Kuehn, K., Hahn, A., Seefried, L. (2023). Impact of restricted phosphorus, calcium-adjusted diet on musculoskeletal and mental health in Hypophosphatasia. It shows the detailed results of the subgroup analyses addressed in the publication. The data presented in the publication/supplementary materials were collected as part of the second stage of the study "Nutritional Status and dietary Effects on Phosphorus metabolism and clinical Symptoms in Hypophosphatasia" (NuSTEPS).