Abstract / Summary
Background/Objectives: Sarcopenia is a major age-related health condition characterized by loss of muscle mass, strength and physical performance. Adequate protein intake is essential for maintaining muscle health, but the role of protein sources and particularly animal-to-plant protein ratio remains unclear. This study aimed to investigate the association between dietary protein sources, particularly animal–plant protein ratio, and low skeletal muscle mass among Lebanese older adults. Methods: A cross-sectional study was performed on 162 older adults aged >60 years using a food frequency questionnaire (FFQ) to assess dietary protein intake. Protein sources were classified as animal- or plant-based. Skeletal muscle mass index was calculated as skeletal muscle mass/height2, and cut-off thresholds for sarcopenia were set at 7.26 kg/m2 for men and 5.45 kg/m2 for women. Handgrip strength and the Short Physical Performance Battery (SPPB) were used to assess muscle strength and physical performance. Associations between protein intake, protein source, and low skeletal muscle mass were evaluated using appropriate statistical analyses. Results: Frequency of low skeletal muscle mass was 49.4%. Logistic regression analysis showed that higher handgrip strength (aOR = 0.92), higher SPPB (aOR = 0.49) and higher intake of animal protein (aOR = 0.87) and plant protein (aOR = 0.88) were significantly associated with lower odds of low skeletal muscle mass. Conclusions: Higher intakes of both animal- and plant-source protein were associated with lower odds of low skeletal muscle mass among Lebanese older adults. Animal-source protein showed a somewhat stronger association than plant-source protein in the present analysis. However, because of the cross-sectional design, these findings should be interpreted as associations and do not establish causality. Longitudinal and intervention studies are needed to clarify whether dietary protein source contributes to changes in skeletal muscle mass and muscle function in older adults.