Chapter 12 - Fruit, Vegetables, and Bone Health

Abstract

Animal and observational epidemiological human studies have found that fruits and vegetables have a beneficial effect on bone health. Most observational human studies are cross-sectional in design and have a relatively small sample size. Only one relatively small randomized controlled trial (RCT) directly examined the association between fruit and vegetable intervention and bone health and revealed a null effect on bone indices. Well-designed longitudinal studies examining the effect of fruit and vegetable consumption on bone mineral density (BMD) changes and risk of osteoporotic fractures are needed to examine this hypothesis. Several mechanisms are proposed for the potential effects of fruits and vegetables on bone health. Among them, acid–base homeostasis theory plays a key role in the beneficial effect of fruits and vegetables. Due to the many limitations in the studies on fruits and vegetables and bone health, better-quality and longer-term RCTs are needed to demonstrate the acid–base hypothesis. Apart from being a major source of base cations, fruits and vegetables are also rich sources of calcium, vitamin K, numerous antioxidant compounds, and other biologically active phytochemicals. The favorable effect of calcium and vitamin K on bone has long been established. An increasing number of studies have suggested that oxidative stress might play a role in the progression of osteoporosis, and dietary antioxidants from fruits and vegetables might reduce oxidative stress and prevent osteoporosis. Fruits and vegetables have a favorable effect on bone health, but more solid evidence is required to demonstrate this hypothesis and test the potential mechanisms of action.