Effects of a Multi-Ingredient MCT–Leucine–Creatine-Based Supplement (TLN-01) on Muscle Mass, Strength, and Plasma Amino Acid Profiles in Older Adults with Sarcopenia: A Randomized Controlled Trial

Background: Sarcopenia, the age-related loss of muscle mass and strength, affects over 20% of older adults in Taiwan and contributes to frailty and functional decline. Nutritional supplementation offers a promising strategy for those unable to engage in structured exercise, yet multi-ingredient MCT–leucine–creatine-based interventions remain understudied in clinically defined sarcopenic populations. Methods: We conducted an 8-week randomized, double-blind, placebo-controlled trial at National Taiwan University Hospital (ClinicalTrials.gov NCT06376266). Seventy-three older adults (mean age 77.3 ± 7.7 years) meeting AWGS 2019 sarcopenia criteria were randomized to TLN-01 (a multi-ingredient supplement containing whey protein, branched-chain amino acids, medium-chain triglycerides, creatine, resveratrol, and vitamin D3, n = 34) or isocaloric placebo (n = 39). Primary outcomes were changes in appendicular skeletal muscle mass (ASM) assessed by DXA and handgrip strength. Targeted plasma amino acid metabolomics (LC-MS) was performed as an exploratory endpoint. Results: ASM increased significantly in the TLN-01 group (+0.42 kg, +3.2%; p < 0.001) but remained unchanged in controls (p = 0.785), with a significant between-group difference (ANCOVA p < 0.01); this absolute change was below the commonly cited minimal clinically important difference. Handgrip strength did not differ significantly between groups (p = 0.32); within-group analysis showed a significant decline in the placebo group (−7.0%; p < 0.001) that was not observed in the intervention group (p = 0.537). Metabolomic analysis revealed reductions in plasma taurine and 1-methylhistidine and an increase in kynurenine; given the absence of clear separation on PCA/PLS-DA, these findings are considered exploratory and hypothesis-generating rather than confirmatory evidence of altered amino acid utilization or proteolysis. No clinically significant adverse metabolic or renal events occurred. Conclusions: Eight weeks of this multi-ingredient MCT–leucine–creatine-based supplement induced a modest increase in muscle mass and attenuated the decline in handgrip strength observed in the placebo group among sarcopenic older adults without a structured exercise program, supporting further investigation as a safe and practical nutritional adjunct in geriatric care.