Protein Intake Important for Bone Mass in People With Rheumatic Disease

New research has highlighted the importance of adequate protein intake for improving lean and bone mass in people with rheumatic diseases (RD), including psoriatic arthritis (PsA), rheumatoid arthritis (RA), osteoarthritis and gout.1

“Individuals with rheumatic conditions may also benefit from protein intakes higher than recommended daily allowance (RDA), due to their high risk of muscle and bone loss. It is unknown, however, whether factors such as chronic inflammation, frequent use of catabolic drugs, such as glucocorticoids, or physical inactivity may limit the usefulness of increased protein intake in this population,” lead investigator Gabriel P. Esteves, Applied Physiology and Nutrition Research Group – School of Physical Education and Sport, and Center of Lifestyle Medicine, Faculdade de Medicina FMUSP, Universidade de Sao Paulo, and colleagues wrote.1

Esteves and colleagues evaluated data from 3,972 individuals with PsA, RA, osteoarthritis and gout from National Health and Nutrition Examination Survey (NHANES) for lean and bone mass, measured at the whole-body, femoral neck and lumbar spine by dual energy X-ray absorptiometry (DXA), and analyzed associations with daily protein intake in absolute and relative to body mass values.2 They used generalized linear models with linear and non-linear associations adjusted for confounding variables and directed acyclic graphs to visualize variables and determine an adjustment set.

The investigators found that there was a linear association between absolute protein intake and lean mass (1.54 kg lean mass per 50 g/day protein [95% CI, 0.78 to 2.30]; P <.001) and a non-linear association for relative protein intake (g/kgBM/day, P <.001), with lean mass increases topping out at protein intake of ∼1.6 g/kgBM/day.1

Furthermore, they found non-linear associations between absolute (P <.001) and relative (P = .005) protein intake and femoral neck bone mineral density (BMD), with femoral neck BMD increases topping out at intakes ∼150 g/day or ∼1.2 g/kgBM/day. There did not find any significant associations for whole-body and spine BMD.1

Esteves and colleagues noted that the magnitudes of associations reported in the study were small to medium and protein intake should be combined with resistance training to increase lean mass or strength, or that protein intake interventions alone focused on frail individuals. They also shared limitations of the study, including its cross-sectional nature, and called for further studies on protein intake in people with RDs. They also emphasized that other RDs, such as systemic lupus erythematosus, would also be useful to evaluate for lean mass and protein intake. Lastly, some historical medication use may have been missed in the study and there may be interactions with historical glucocorticoid use

“These associations are consistent with the body of literature from individuals without RD, aligning with recommendations to increase protein intake in populations with high risk for muscle and bone loss. These findings suggest that protein intakes higher than the current RDA might be a prudent goal for nutritional therapy in individuals with RD. Additionally, our study provides a rationale for designing future randomized controlled trials to test the efficacy and feasibility of dietary protein intakes that are higher than current RDA (e.g., 1.2 – 1.6 g/kgBM/day) to protect musculoskeletal health in this population,” Esteves and colleagues concluded.1

REFERENCES

1. Esteves GP, Swinton P, Sale C, Gualano B, Roschel H, Dolan E. Non-linear associations between protein intake and lean and femur bone mass in individuals with rheumatic diseases: findings from the NHANES 2007–2018. J. Nutr. Physiol. Published online May 22, 2025. doi.org/10.1016/j.jnphys.2025.100004

2. National Health and Nutrition Examination Survey. Webpage. Center for Disease Control: National Center for Health Statistics. Updated 2025. https://www.cdc.gov/nchs/nhanes/index.html