Effects of Medium-Chain Triglyceride and Medium-Chain Fatty Acid Supplementation on Skeletal Muscle Morphology, Metabolism, and Function in Adult Humans and Animals: A Protocol for a Systematic Review and Meta-Analysis
Abstract
Background. Medium-chain triglycerides (MCT) and medium-chain fatty acids (MCFA) have distinct metabolic properties and may influence skeletal muscle metabolism and function; however, evidence is fragmented and inconsistent.
Aim. The aim of this systematic review and meta-analysis is to evaluate the clinically relevant and mechanistic effects of MCFA/MCT supplementation on skeletal muscle morphology, metabolism, and function in adult humans and adult animal models.
Data Sources. Peer-reviewed studies will be identified through systematic searches of major electronic databases, and reference lists of included studies will be screened to identify additional relevant publications.
Participants and Interventions. Eligible studies will include randomised controlled trials conducted in adult human and adult animal models, comparing the effects of oral MCFA/MCT supplementation with placebo oils, usual diet, or calorie-matched controls.
Study Appraisal and Synthesis Methods. Risk of bias will be assessed using RoB 2 for human studies and the SYRCLE tool for animal studies. Where appropriate, random-effects meta-analyses will be conducted; otherwise, findings will be synthesised narratively. The certainty of evidence will be evaluated using the GRADE framework. Human and animal studies will be synthesised and analysed separately to distinguish clinically relevant outcomes from mechanistic evidence and to avoid inappropriate cross-species inference.
Conclusions. This protocol outlines a transparent and rigorous approach to synthesising current evidence on MCFA/MCT supplementation and skeletal muscle-related outcomes. The findings are expected to clarify existing evidence gaps and inform future research in nutrition and muscle health.
Keywords: Medium-chain fatty acids; skeletal muscle; muscle metabolism; muscle function; randomised controlled trials
References
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