Changes in bone mineral and matrix in response to a soft diet

Alterations in the magnitude of habitual mechanical loads upon the skeleton may not only affect bone architecture, but also influence the nature of the bone matrix. We tested the hypothesis that changing the mechanical consistency of the diet affects both the mineral and non-mineralized moieties of bone matrix. Female rats were fed a soft diet (powdered chow as a paste), while control animals were fed the standard chow. After 8 or 20 wks, animals were killed. Cranial (mandible, maxilla, parietal, and frontal) bones and ulnae were analyzed for mineralization density by quantitative backscattered electron microscopy, and sulphated glycosaminoglycan levels with alcian blue staining were measured by microdensitometry. The soft diet group showed a significant increase in mineralization density distribution at almost all cranial sites and a reduction in alcian blue staining in alveolar bone. Altering the consistency of the diet significantly affects mineral concentration and glycosaminoglycan content of alveolar bone.