Erythrocyte Fatty Acid Patterns Are Associated with Skeletal Muscle Mass in Chinese Children

Background: Nutritional factors are important for skeletal muscle mass and grip strength development in children. Objectives: This study aimed to investigate the relationship between erythrocyte membrane fatty acid patterns (FAPs) and skeletal muscle mass and grip strength in children. MethodsA total of 452 children aged 6-9 y were included in this study. Appendicular skeletal muscle mass (ASM) was assessed by dual-energy X-ray absorptiometry. Hand grip strength was determined by the Jamar Plus+ hand dynamometer (Sammons Preston). Appendicular skeletal muscle mass index (ASMI) was calculated, and the relative concentrations of 20 fatty acids in erythrocyte membranes were measured by gas chromatography-mass spectrometry. Factor analysis was used to explore the relationship between fatty acids and skeletal muscle mass and grip strength. Results: Five FAPs were identified by factor analysis, and after adjusting for covariates, a multiple linear regression model showed that FAP2 (high C17:0, C20:5 n-3, C22:6 n-3) showed a negative correlation with ASM (beta = -0.214; P < 0.001), ASMI (beta = -0.085; P < 0.001), and left-hand grip strength (beta = -0.235; P = 0.012). FAP3 (high C14:0, C15:0, C16:0, C16:1 n-7, low C20:4 n-6) scores were positively correlated with ASM (beta = 0.134, P = 0.017). No other associations between FAPs and skeletal muscle mass were found. Conclusions: The relationship between different FAPs and skeletal muscle health in children aged 6-9 y may be different. The pattern characterized by higher concentrations of C17:0, C20:5 n-3, and C22:6 n-3 in erythrocyte membranes may be associated with lower skeletal muscle mass. The pattern featuring higher concentrations of C14:0, C15:0, C16:0, and C16:1 n-7 and lower concentrations of C20:4 n-6 may be protective factors for muscle mass.