Effect of an Energy-Restricted, Nutritionally Complete, Higher Protein Meal Plan on Body Composition and Mobility in Older Adults With Obesity: A Randomized Controlled Trial.
Study Goal
The researchers aimed to determine whether a high-protein diet could preserve muscle mass and function in older adults undergoing caloric restriction for weight loss.
Results Summary
The high-protein diet led to significant total body and fat mass loss while preserving lean body mass and mobility, though no differential treatment effect was observed for lean mass changes. Gait speed showed a slight trend toward improvement in the weight loss group compared to the weight stability group.
Population
Older adults (70.3 ± 3.7 years, 74% women, 27% African American) with obesity (BMI 35.4 ± 3.3 kg/m², 47% total body fat).
Effective Dosage
1.2-1.5 g/kg/d
Duration
6 months
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
higher protein weight loss program (providing 1.2-1.5 g/kg/d) | decrease | total body mass | older adults with obesity | -8.17 [-9.56, -6.77] kg | significantly reduced | #1 |
higher protein weight loss program (providing 1.2-1.5 g/kg/d) | decrease | fat mass | older adults with obesity | -7.1 [-8.1, -6.1] kg; -15.9% change from baseline | lost | #2 |
higher protein weight loss program (providing 1.2-1.5 g/kg/d) | no change | lean mass | older adults with obesity | -0.81 [-1.40, -0.23] kg vs weight stability group: -0.24 [-0.85, 0.36] kg | no differential treatment effect observed for change | #3 |
higher protein weight loss program (providing 1.2-1.5 g/kg/d) | no change | 400-meter gait speed | older adults with obesity | 0.01 (-0.02, 0.04) m/s compared with weight stability group: -0.02 (-0.05, 0.01) m/s | unchanged from baseline | #4 |
intentional weight loss using a high-protein diet | decrease | total body mass and fat mass | relatively high-functioning older adults with obesity | - | effective in producing significant loss | #5 |
intentional weight loss using a high-protein diet | no change | lean body mass and mobility | relatively high-functioning older adults with obesity | - | helping preserve | #6 |
BACKGROUND: Increasing protein content of the diet might be an effective strategy to preserve muscle mass in older adults undergoing caloric restriction, thereby preserving muscle function. METHODS: Ninety-six older adults (70.3 ± 3.7 years, 74% women, 27% African American) with obesity (35.4 ± 3.3 kg/m2; 47% total body fat) were randomized to a 6-month higher protein (providing 1.2-1.5 g/kg/d) weight loss (WL) program, utilizing the Medifast 4&2&1 Plan, or to weight stability (WS). Dual-energy x-ray absorptiometry-acquired total body mass and composition, and fast gait speed over 400 m was assessed at baseline, 3, and 6 months. RESULTS: At baseline, dual-energy x-ray absorptiometry-acquired total body, fat, and lean masses were 95.9 ± 14.6, 44.6 ± 7.6, and 48.7 ± 9.5 kg, respectively, and 400-m gait speed was 1.17 ± 0.20 m/s. Total body mass was significantly reduced in the WL group (-8.17 [-9.56, -6.77] kg) compared with the WS group (-1.16 [-2.59, 0.27] kg), with 87% of total mass lost as fat (WL: -7.1 [-8.1, -6.1] kg; -15.9% change from baseline). A differential treatment effect was not observed for change in lean mass (WL: -0.81 [-1.40, -0.23] kg vs WS: -0.24 [-0.85, 0.36] kg). Four-hundred-meter gait speed was also unchanged from baseline although trends suggest slightly increased gait speed in the WL group [0.01 (-0.02, 0.04) m/s] compared with the WS group [-0.02 (-0.05, 0.01) m/s]. CONCLUSION: Intentional weight loss using a high-protein diet is effective in producing significant total body mass and fat mass loss, while helping preserve lean body mass and mobility, in relatively high-functioning older adults with obesity.