Changes in Fat-Free Mass, Protein Intake and Habitual Physical Activity Following Roux-en-Y Gastric Bypass Surgery: A Prospective Study

The effects of protein intake higher than the recommended value on body composition changes after bariatric surgery: A meta-analysis of randomized controlled trials

BACKGROUND & AIMS

There is a lack of a meta-analysis to comprehensively assess the effectiveness of higher protein intake in addition to the recommended value on body composition post-bariatric surgery. We aimed to perform a meta-analysis of randomized controlled trials to determine the effects of protein intake higher than the recommended value on body composition changes after bariatric surgery.

METHODS

Electronic databases, including Scopus, PubMed/Medline, and Web of Sciences, were searched until July 2023. Studies that assessed the effect of protein intake higher than the recommended value on postoperative body composition, i.e., weight, body mass index (BMI), fat mass (FM), fat-free mass (FFM), percent fat mass (PFM), and percent total weight loss (%TWL), were eligible. For each outcome, the mean and standard deviation (for changes from baseline) were used to synthesize the data.

RESULTS

Eight trials were included in the current study. The results of the meta-analysis indicated protein intake higher than the recommended value after bariatric surgery led to more weight loss by 4.95 kg (95 % CI: -9.41 to -0.49) and FM loss by 7.64 kg (95 % CI: -14.01 to -1.28) compared with the control group. However, it had no significant effects on postoperative changes in BMI, FFM, PFM, or %TWL. There were no significant differences in body composition between protein sources obtained from diet and supplementation. When data was stratified based on the amount of added protein, we found a significant reduction in weight (MD: -7.80 kg; 95 % CI: -14.50 to -1.10) in patients who consumed protein ≥ 40 g/d in addition to the recommended value. Besides, protein intake higher than the recommended value declined FFM loss in patients who underwent laparoscopic sleeve gastrectomy (LSG) (MD: 6.52 kg; 95 % CI: 0.99 to 12.02).

CONCLUSION

The results of the current meta-analysis indicated that protein intake higher than the recommended value might cause greater weight and FM loss after bariatric surgery than a normal protein diet. However, our findings did not support the role of additional protein in the preservation of FFM, except in patients with LSG.

Prevalence of Perceived Barriers to Physical Activity Among Pre- and Post-Metabolic and Bariatric Surgery Patients: A Cross-Sectional Study

OBJECTIVE

This study aims to describe and compare the prevalence of perceived barriers to physical activity (PBPA) in pre- and post-metabolic and bariatric surgery (MBS) patients and assess the association of these barriers with their physical activity levels.

METHODS

A cross-sectional study included pre-operative (n = 63) and post-operative (n = 119) groups. Sociodemographic characteristics, leisure-time physical activity levels, and PBPA data were collected. Descriptive statistics, chi-square, and Fisher's exact tests, and binomial logistic regression analyses were used for comparisons and associations.

RESULTS

Compared to the pre-operative group, the post-operative group had a lower prevalence of barriers in the physical domain (p = 0.036) and the behavioral domain (p = 0.004). However, there were no significant differences in the environmental (p = 0.531) or social (p = 0.597) domains. Pre-MBS patients were more likely to be physically inactive when perceiving barriers in the environmental (p = 0.048) and behavioral (p = 0.048) domains. In contrast, post-surgical patients were more likely to be physically inactive when perceiving barriers in the environmental (p = 0.027), social (p = 0.020), and behavioral (p = 0.037) domains.

CONCLUSION

The results show that individuals who underwent metabolic and bariatric surgery have a lower prevalence of behavioral and physical PBPA compared to those awaiting the procedure. The perception of barriers to physical activity in the environmental and behavioral domains increases the likelihood of physical inactivity in both pre- and post-MBS patients, while in the social domain, it was only associated with physical activity in post-MBS patients.