The plasma proteome is favorably modified by a high protein diet but not by additional resistance training in older adults: A 17-week randomized controlled trial.
Study Goal
The researchers aimed to compare the effects of a habitual diet, recommended protein intake, and high protein intake—with and without strength training—on the plasma proteome and body composition in older adults.
Results Summary
The high-protein diet combined with exercise led to reduced body fat, increased muscle mass, and changes in 14 plasma proteins linked to immune function, lipid transport, and blood coagulation. Strength training did not further alter the proteome.
Population
Older adults (65-85 years), both women and men.
Effective Dosage
High-protein group: 1.63 ± 0.36 g/kg BW/day; recommended protein group: 1.06 ± 0.26 g/kg BW/day.
Duration
6 weeks of dietary intervention, followed by 8 weeks of additional strength training.
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
high protein intake (HP) | increase | protein intake | Participants of the HP group | from 0.80 ± 0.31 to 1.63 ± 0.36 g/kg BW/d | doubled | #1 |
recommended protein intake (RP) | increase | protein intake | RP group | from 0.89 ± 0.28 to 1.06 ± 0.26 g/kg BW/d | increased | #2 |
habitual diet (CON) | no change | protein intake | CON group | stable throughout the study | kept stable | #3 |
Combined exercise and HP | decrease and increase | body composition | - | - | initiated notable changes, resulting in a reduction in bodyfat and increased muscle mass | #4 |
HP diet | increase | 14 proteins | - | 14 | significantly affected | #5 |
HP diet | increase | innate immune system, lipid transport and blood coagulation | - | - | regulating | #6 |
additional strength training | no change | proteome | - | - | did not elicit further changes | #7 |
Combined HP and resistance exercise | increase | body composition | healthy older adults | - | seem to induce favorable changes | #8 |
high protein diet | increase | innate immune system, lipid transport and blood coagulation system | - | - | point to a beneficial impact | #9 |
BACKGROUND: The age-related loss of muscle mass significantly contributes to the development of chronic diseases, loss of mobility and dependency on others, yet could be improved by an optimized lifestyle. OBJECTIVE: The goal of this randomized controlled trial was to compare the influence of a habitual diet (CON) with either a diet containing the recommended protein intake (RP) or a high protein intake (HP), both with and without strength training, on the plasma proteome in older adults. METHODS: One hundred and thirty-six women and men (65-85 years) were randomly assigned to three intervention groups. CON continued their habitual diet; participants of the HP and RP group consumed either high protein or standard foods. After 6 weeks of dietary intervention, HP and RP groups additionally started a strength training intervention twice per week for 8 weeks. Twenty-four hours dietary recalls were performed every 7-10 days. Body composition was assessed and blood taken. Plasma proteomics were assessed with LC-MS. RESULTS: Participants of the HP group doubled their baseline protein intake from 0.80 ± 0.31 to 1.63 ± 0.36 g/kg BW/d; RP increased protein intake from 0.89 ± 0.28 to 1.06 ± 0.26 g/kg BW/d. The CON group kept the protein intake stable throughout the study. Combined exercise and HP initiated notable changes, resulting in a reduction in bodyfat and increased muscle mass. Proteomics analyses revealed 14 significantly affected proteins by HP diet, regulating innate immune system, lipid transport and blood coagulation, yet the additional strength training did not elicit further changes. CONCLUSIONS: Combined HP and resistance exercise in healthy older adults seem to induce favorable changes in the body composition. Changes in the plasma proteome due to the high protein diet point to a beneficial impact for the innate immune system, lipid transport and blood coagulation system, all of which are involved in chronic disease development. CLINICAL TRIAL REGISTRATION: The study was registered at ClinicalTrials.gov (NCT04023513).