Effects of soy protein-rich meals on muscle health of older adults in long-term care: A randomized clinical trial.

2024-10
Nutrition (Burbank, Los Angeles County, Calif.) 126
- Wuke Yuan
- Min Chen
- Yanqiu Chen
- Danfeng Xu
- Zhen Li
- Huijing Bai
- Qi Xu
- Yuanrong Jiang
- Jie Gu
- Shengqi Li
- Chenxi Su
- Lili Gu
- Jiaxin Fang
- Xinyao Zhu
- Jianqin Sun
- Jie Chen

PubMed: 39003895
DOI: 10.1016/j.nut.2024.112507

Study Design

Type: Randomized Controlled Trial (RCT)
Sample size: n = 84
Population: 84 older adults from a long-term care facility
Methods: 12-week single-center randomized controlled trial with a control-group and open-label design; intervention group consumed three meals with 30 g of soy protein per day, control group maintained habitual diets
Blinding: Open-label
Duration: 12 weeks
Funding: Unclear

Objective

This study investigated the effects of a soy protein-rich meal intervention on the muscle health of older adults in long-term care facilities.

Methods

A 12-week single-center randomized controlled trial with a control-group and open-label design was conducted. Eighty-four older adults from a long-term care facility participated in the study. The chefs at the facility cooked three meals using soy protein-rich recipes designed by dieticians. For 12 weeks, the intervention group participants consumed three meals with 30 g of soy protein (10 g/meal) per day, and the control group participants maintained their habitual diets.

Results

The 84 participants (mean age, 84.9 ± 7.0 years; 61.9% female) were randomly assigned to an intervention group (43 participants) and a control group (41 participants). The intervention group exhibited significant increases in several lean mass indicators, namely soft lean mass (mean, 1.43 kg; 95% confidence interval kg), skeletal muscle mass (mean, 1.20 kg; 95% CI: 0.43-1.96 kg), appendicular skeletal muscle mass (mean, 0.79 kg; 95% CI: 0.07-1.52 kg), and skeletal muscle index (mean, 0.37 kg/m²; 95% CI: 0.05-0.68 kg/m²) (all P < 0.05). These changes were not observed in the control group (all P > 0.05). Notably, calf circumference decreased significantly in the control group (mean, -0.98 cm; 95% CI: -1.61 to -0.36 cm) but was maintained in the intervention group. The differences in the calf circumference and 6-m walk performance of the two groups were significant (P < 0.05).

Conclusions

The 12-week soy protein-rich meal intervention improved the muscle mass and 6-m walk performance of older adults in a long-term care facility.

Research Insights

Soy Protein→Improved 6-Meter Walk Performance
The differences in the calf circumference and 6-m walk performance of the two groups were significant (P < 0.05)
Effect
Beneficial
Effect size
Small
Dose
30 g of soy protein (10 g/meal) per day
Soy Protein→Increased Appendicular Skeletal Muscle Mass
appendicular skeletal muscle mass (mean, 0.79 kg; 95% CI: 0.07-1.52 kg)
Effect
Beneficial
Effect size
Moderate
Dose
30 g of soy protein (10 g/meal) per day
Soy Protein→Increased Lean Body Mass
The intervention group exhibited significant increases in several lean mass indicators, namely soft lean mass (mean, 1.43 kg; 95% CI: 0.20-1.65 kg)
Effect
Beneficial
Effect size
Moderate
Dose
30 g of soy protein (10 g/meal) per day
Soy Protein→Increased Skeletal Muscle Index
skeletal muscle index (mean, 0.37 kg/m2; 95% CI: 0.05-0.68 kg/m2)
Effect
Beneficial
Effect size
Moderate
Dose
30 g of soy protein (10 g/meal) per day
Soy Protein→Increased Skeletal Muscle Mass
skeletal muscle mass (mean, 1.20 kg; 95% CI: 0.43-1.96 kg)
Effect
Beneficial
Effect size
Moderate
Dose
30 g of soy protein (10 g/meal) per day
Soy Protein→Maintained Calf Circumference
calf circumference decreased significantly in the control group (mean, -0.98 cm; 95% CI: -1.61 to -0.36 cm) but was maintained in the intervention group
Effect
Beneficial
Effect size
Small
Dose
30 g of soy protein (10 g/meal) per day