100% orange juice has a unique blend of components that may have beneficial effects on bone health. Fortified orange juice is considered an excellent source of calcium, and many fortified juices include vitamin D to help support bone health.(Weaver) Fortification of orange juice with vitamins D2 or D3 was reported to be just as effective as an oral vitamin supplement in maintaining vitamin D status in adults.(Biancuzzo). Similarly, vitamin D fortified orange juice was effective in increasing blood vitamin D levels in children.(Economos)  An NHANES analysis reported that consumption of calcium and vitamin D fortified orange juice was positively associated with femur bone mineral density in children and with femur bone mineral content in children and adults.(Lee)

Orange juice is also a good source of potassium and contains organic acids like citrate and malate. The combination of the organic acids and minerals helps the blood maintain a normal, properly balanced acid:base ratio at a slightly basic or alkaline value. Unregulated, higher levels of acidity could lead to loss of calcium from bone and reduce bone density and strength. Other components of citrus, particularly polyphenols, may be involved in supportive roles in the mechanisms of bone health through their actions on osteoblasts and osteoclasts (Horcajada, Sacco).

References

Biancuzzo RM et al. Am J Clin Nutr. 2010;91:1621-1626.
Economos CD et al. J Acad Nutr Diet. 2014;114:709-717.
Horcajada MN et al. Curr Mol Pharmacol. 2012;5:205-218.
Lee SG et al. J Med Food. 2014;17:1142–1150.
Sacco SM et al. Br J Clin Pharmacol. 2013;75:697-707.
Weaver CM. Oral Dis. 2016; Epub June 2.