OsteoBalance‡ provides 514 mg of calcium per serving from calcium citrate/malate and calcium malate, along with a comprehensive profile of important bone-building nutrients. Randomized, double-blind, placebo-controlled studies have reported statistically significant benefits of calcium supplementation for bone health. Calcium citrate/malate has excellent bioavailability and provided bone mass support in postmenopausal women with low dietary calcium intake in a two-year, double-blind placebo-controlled trial. One study indicated that concomitant supplementation of the trace minerals zinc, copper and manganese with calcium citrate/malate helped to promote healthy bone metabolism in postmenopausal subjects. Magnesium also supports healthy bone mineral density. Boron plays an important role in reducing urinary calcium and magnesium excretion. Like boron, vitamin D3 reduces urinary calcium loss, but also enhances calcium absorption.