The purpose of this application is to request funds for continuation of a prospective, randomized, double-blind, placebo-controlled study of the efficacy of increased calcium intake in the prevention of spine fractures and bone loss in elderly women. Funding for this study began in June of 1987 by the National Dairy Promotion and Research Board and the National Dairy Council and is committed until December 31, 1990. Application for renewal for 1991-1993 was scheduled for submission in June 1990. The NDC administrators have stated that there may not be sufficient funds to continue it and they have requested that funds be sought elsewhere for completion of the study. The hypothesis to be tested in the project is that spine fractures and bone loss in elderly women with low calcium intakes can be reduced by adding 1200 mg.day of calcium as carbonate to the diet. The specific aims are: to continue a study of 223 women over the age of 60; to continue performing annual spine radiographs under standard conditions on each subject; to continue monitoring the clinical history of appendicular fracture; to continue performing semiannual measurements of bone mineral content of the forearm; to continue performing measurements of serum levels of 25-hydroxy vitamin D on a subset of 50 subjects; and to continue administration of placebo or calcium, 1200 mg/day, as calcium as carbonate to randomly chosen subjects in a double blind design, The principle endpoints will be vertebral deformity by strictly defined morphometric criteria and forearm bone mineral density. Appendicular fractures will be monitored and may also accumulate to a sufficient number to become an endpoint.