BACKGROUND: There has been a resurgence of interest in the controversial relation between dietary protein and bone health. OBJECTIVE: This article reports on the first systematic review and meta-analysis of the relation between protein and bone health in healthy human adults. DESIGN: The MEDLINE (January 1966 to September 2007) and EMBASE (1974 to July 2008) databases were electronically searched for all relevant studies of healthy adults; studies of calcium excretion or calcium balance were...