The effect of additional protein on lean body mass preservation in post-bariatric surgery patients: a systematic review.
Study Goal
The researchers aimed to determine the effect of additional protein intake, including casein, on lean body mass preservation in post-bariatric patients.
Results Summary
The study found inconclusive evidence for lean body mass preservation due to protein supplementation, including casein, with only two of five studies showing significant effects. No significant differences were observed in body fat mass, total body water, or body mass index between high-protein and control groups.
Population
Post-bariatric surgery patients
Effective Dosage
≥60 g/day (total protein intake, not casein-specific)
Duration
At least one month
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
additional protein intake (≥60 g/day) | decrease | lean body mass (LBM) | post-bariatric patients | - | resulted in significant LBM preservation | #1 |
high-protein diet | decrease | body fat mass | post-bariatric patients | - | significant difference in the reduction | #2 |
high-protein diet | neutral | resting metabolic rate | post-bariatric patients | - | significant difference | #3 |
protein supplementation or a high-protein diet | no change | total body water loss | post-bariatric patients | - | no significant difference | #4 |
protein supplementation or a high-protein diet | no change | body mass index change | post-bariatric patients | - | no significant difference | #5 |
BACKGROUND: As result of bariatric surgery, patients are susceptible to protein deficiency which can result in undesirable lean body mass (LBM) loss. Consumption of high-protein diets or supplements could counteract this, but evidence about the effect is scarce. This paper systematically reviewed the literature to determine the effect of additional protein intake (≥60 g/day) on LBM preservation in post-bariatric patients. METHODS: An electronic search of PubMed, EMBASE and the Cochrane Library was conducted. Studies were included if patients received a high-protein diet or protein supplements for at least one month, and LBM was assessed. The primary outcome was difference in mean LBM loss between the experimental (protein) and control group. Secondary outcomes were differences in body fat mass, total body water, body mass index and resting metabolic rate. RESULTS: Two of the five included studies (n = 223) showed that consumption of proteins resulted in significant LBM preservation. Only one study reported a significant difference in the reduction of body fat mass and resting metabolic rate in favour of a high-protein diet, but none of the studies showed a significant difference in total body water loss or body mass index change between the two groups. CONCLUSIONS: This paper showed inconclusive evidence for LBM preservation due to protein supplementation or a high-protein diet in post-bariatric patients. This outcome might be subjected to certain limitations, including a lack of blinding and a low compliance rate reported in the included studies. More specific and personalized recommendations regarding protein intake may need to be established by high quality research. Studies investigating the quantity (g/day) and quality (whey, casein or soy) of proteins are also needed.