Systematic Review Suggests Protein-Rich Diet Is Beneficial for Bone Health

Dietary protein intake is necessary for growth and maintenance of many organs in the body. A recent review of the benefits and safety of dietary protein for bone health concluded that a protein-rich diet is beneficial for adult bone health.

The systematic review, endorsed by the European Society for Clinical and Economical Aspects of Osteoporosis, Osteoarthritic, and Musculoskeletal Diseases and the International Osteoporosis Foundation, considered and summarized findings from several previous systematic reviews and meta-analyses that addressed the benefits and risks of dietary protein intakes for bone health in adults.

“Indeed, based on studies in which the administration of large amount of acid was increasing bone resorption, it has been claimed that a diet rich in compounds whose metabolism is generating acid would lead to low-grade metabolic acidosis, impairing thereby osteoblast function, stimulating osteoclast survival and activity, increasing bone resorption, and decreasing bone mass and strength,” explained the authors. “This has raised numerous debates, sometimes more emotional than based on evidence.”

The main findings of the literature review included:

• Bone mineral density (BMD), an important determinant of bone strength, appears to be positively associated with dietary protein intakes.
• Risks of hip fracture are modestly decreased with greater dietary protein intake, when calcium intakes are adequate.
• Protein and calcium combined in dairy products have beneficial effects on calciotropic hormones, bone turnover markers, and BMD.
• There appears to be no specific evidence of osteoporosis progression, fragility fractures or altered bone strength with the acid load originating from a balanced diet.

“Adequate intake of dietary protein, together with calcium, is needed for optimal bone growth in children and the maintenance of healthy bone at all ages. This message needs to be reinforced in view of currently circulating myths suggesting that too much protein causes 'acid load' and is damaging to bone health,” Professor René Rizzoli, Professor at the Division of Bone Diseases of the Geneva University Hospitals and Faculty of Medicine, said in a statement.

The authors noted that because there is no evidence that diet-derived acid load is harmful for bone health, insufficient dietary protein intakes may be a more severe problem than protein excess for elderly people.

“In fact, in the elderly, we find that a common problem is not too much protein, but too little. This review of the literature confirms that a balanced diet with sufficient protein intake, regardless whether of animal or vegetable source, clearly benefits bone health when accompanied by adequate calcium intake,” Rizzoli continued. “This is particularly important for seniors with osteoporosis, and individuals at risk of malnutrition due to acute or chronic illness, or recovering from an injury."

The researchers emphasized the need for long-term, well-controlled randomized trials in the future in order to further evaluate the influence of dietary protein intake on fracture risk.

Reference

Rizzoli R, Biver E, Bonjour JP, et al. Benefits and safety of dietary protein for bone health-an expert consensus paper endorsed by the European Society for Clinical and Economical Aspects of Osteopororosis, Osteoarthritis, and Musculoskeletal Diseases and by the International Osteoporosis Foundation. [published online May 8, 2018]. doi: 10.1007/s00198-018-4534-5.