The interaction between dietary protein and bone health

Area of Science:

• Nutrition Science
• Bone Metabolism
• Dietary Protein Research

Background:

• The role of dietary protein in bone health is debated, with potential benefits for bone remodeling countered by concerns about acid load and calcium loss.
• Existing research presents conflicting findings on protein's impact on skeletal integrity.

Purpose of the Study:

• To review the effects of dietary protein on bone mass, density, resorption and formation markers, and fracture risk.
• To examine evidence from cross-sectional and longitudinal studies, considering various protein sources like animal, vegetable, soy, and milk proteins.

Main Methods:

• Systematic review of cross-sectional and longitudinal studies.
• Analysis of dietary protein's impact on bone mineral density, bone turnover markers, and fracture incidence.
• Inclusion of studies examining different protein types (meat, vegetable, soy, milk).

Main Results:

• Dietary protein appears to have a modest beneficial effect on bone markers and bone density.
• The overall impact of protein on bone health may depend on interactions with other dietary factors, such as calcium intake and intake of fruits and vegetables.
• A consistent link between dietary protein and reduced fracture risk has not been established, likely due to confounding factors like fall risk.

Conclusions:

• Dietary protein intake demonstrates a modest positive influence on bone metabolism markers and bone density.
• The net effect of dietary protein on bone health is complex and influenced by the overall dietary context.
• Further research is needed to clarify the relationship between protein intake and fracture risk, and to compare the efficacy of different protein sources.