Effects of Probiotics, Prebiotics, and Synbiotics on Sarcopenia Parameters in Older Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Context: There is scarce evidence about which probiotic, prebiotic, or synbiotic supplementation is the most appropriate to improve sarcopenia parameters, and this presents a challenge.

Objective: The effects of consumption of probiotics, prebiotics, and synbiotics on sarcopenia, muscle strength, muscle mass, and physical performance and function were assessed in this study. In addition, another aim of the study was to determine the best probiotic, prebiotic, and/or synbiotic for the management of sarcopenia in older adults.

Data sources: A systematic search was conducted in the MEDLINE/PubMed, Cochrane Library, SCOPUS databases, and other sources (eg, references obtained from articles identified in databases).

Data extraction: The search was limited from 2000 to 2023 and was based on sarcopenia parameters, and probiotics, prebiotics, or synbiotics supplementation. The quality of each included study also was assessed.

Data analysis: A meta-analysis was performed with the Review Manager program and publication bias and sensitivity analysis were performed.

Results: Eight randomized controlled trials (RCTs) were included in the systematic review and 4 in the meta-analysis. Results showed that probiotics supplementation improved muscle strength and physical performance and function and suggested a beneficial effect on muscle mass. Prebiotics are suggested to be effective on muscle strength. The meta-analysis also determined that probiotic interventions were effective in increasing muscle strength by handgrip strength (mean difference [MD], 2.50 kg [95% CI, 1.33-3.66]; P < .0001) and physical performance and function by gait speed (MD, 0.10 m/s [95% CI, 1.33-3.66]; P < .0001) and physical performance and function by gait speed (MD, 0.10 m/s [95%CI, 0.03-0.16]; P = .003), but when sensitivity analysis was applied, the effectiveness was only maintained for gait speed.

Conclusion: Nutritional strategies based on probiotic supplementation seem to improve muscle strength and physical function. More robust research is needed with high-quality RCTs to confirm probiotics' effects. There is still limited evidence about prebiotic and synbiotic strategies, and more evidence is needed to elucidate their effects on sarcopenia parameters.

Systematic review registration: PROSPERO registration no. CRD42022360514.