TOPLINE:

Among older adults with overweight or obesity undergoing a weight-loss intervention, those with a higher protein intake had increased hip bone strength in the short term but no significant change in bone density over time; greater weight loss was linked to bone density loss at 18 months.

METHODOLOGY:

• Researchers conducted a double-blind randomized trial to examine whether higher protein intake could protect hip bone health during intentional weight loss in 187 older adults (aged 65-85 years) with overweight or obesity.
• Participants were enrolled at a US-based center between 2017 and 2020, with follow-up through 2022; 172 participants had evaluable hip CT scans (mean age, 71.5 years; 66% women).
• All participants underwent a 6-month weight-loss program combining calorie restriction and supervised aerobic exercise, followed by a 12-month weight-maintenance phase.
• Participants were randomly assigned to a recommended protein intake group (0.8 g/kg/d) or groups with a higher protein intake of 1.2 g/kg/d for either 6 months only or the full 18 months; supplements were used to meet targets, and diets were calorie matched.
• Hip outcomes, including bone mineral density (BMD), cortical thickness, and estimated bone strength, were measured using CT and bone density scans at baseline and 6 and 18 months. The primary outcome was the 18-month change in total hip trabecular volumetric BMD and femoral cortical thickness.

TAKEAWAY:

• Participants lost a mean of 8.0% of body weight at 6 months, with no significant differences observed between protein groups, and maintained a mean of 5.0% of weight loss at 18 months.
• At 6 months, participants on a higher protein intake for all 18 months had a greater increase in estimated hip bone strength than those on a recommended protein intake (3.8% vs 0.5%; P = .02), but this lost significance after a statistical correction; between-group differences were not significant at 18 months.
• Greater weight loss was associated with greater gains in hip bone strength at 6 months (Spearman’s correlation coefficient, -0.24; P = .007) but associated with a greater loss of hip trabecular volumetric BMD at 18 months (Spearman’s correlation coefficient, 0.24; P = .011) and a greater loss of total hip areal BMD at both timepoints (P < .001 for both).
• Hip cortical volumetric BMD increased by 1.6%-2.0% at 6 months in all groups and remained higher at 18 months. Changes in total hip trabecular volumetric BMD and femoral cortical thickness did not differ significantly between the protein groups.

IN PRACTICE:

“This [randomized controlled trial] found protein supplementation improved hip bone strength during a caloric restriction and aerobic exercise [weight loss] intervention,” the authors of the study wrote.

SOURCE:

This study was led by Ashley A. Weaver, PhD, Wake Forest University School of Medicine in Winston-Salem, North Carolina. It was published online on January 19, 2026, in Osteoporosis International.

LIMITATIONS:

This study lacked a nonexercising control group, which limited the ability to determine the effects of exercise on bone changes. The exercise program did not include resistance training. Enrollment shortfalls and missing hip CT scans reduced statistical power.

DISCLOSURES:

This study received funding from the National Institute on Aging and the Swiss Federal Institute of Technology in Zurich Domain. The researchers acknowledged using resources of a research unit funded by the National Center for Advancing Translational Sciences. The authors did not report any conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.