Plasma Saturated Fatty Acids Are Inversely Associated With Lean Mass And Strength In Adults

Several studies have suggested that increased intake of saturated fatty acids (SFAs) may have a pro-inflammatory effect, potentially impacting muscle mass and strength. However, the relationship of plasma SFAs and their subtypes (which reflect dietary SFA intake) with muscle mass and strength remains poorly understood. PURPOSE: To evaluate the association of plasma SFAs and their subtypes with lean mass and handgrip strength in adults. METHODS: A cross-sectional study was conducted with 896 participants aged 20-59 years, selected from a subsample of the National Health and Nutrition Examination Survey (NHANES) 2011-2012. Plasma total SFAs and their subtypes were detected using gas chromatography-mass spectrometry. Lean mass was assessed using dual-energy X-ray absorptiometry, with evaluations of both total lean mass and appendicular lean mass. Muscle strength was measured using a handgrip dynamometer, with combined grip strength calculated by summing the highest values from each hand. Linear regression analysis was conducted to examine the association between SFAs, lean mass, and handgrip strength, adjusting for energy intake, protein intake, smoking, family income, glucose levels, alcohol intake, marital status, education level, arthritis, fat mass (kg), physical activity, age, sex, and race. RESULTS: Total lean mass was negatively associated with total plasma SFAs (β = -0.0004; p-value = 0.020) and several of their subtypes such as plasma levels of stearic acid, palmitic acid, arachidic acid, tricosanoic acid, lignoceric acid, and docosanoic acid. Similarly, appendicular lean mass was negatively associated with plasma total saturated fatty acids (β = -0.0003; p-value = 0.004), as well as with several specific subtypes, including palmitic acid, stearic acid, margaric acid, pentadecanoic acid, and myristic acid. Handgrip strength also demonstrated a negative association with total plasma saturated fatty acids (β = -0.0009; p-value = 0.024), including specific subtypes such as lauric acid, palmitic acid, capric acid, margaric acid, pentadecanoic acid, and myristic acid. CONCLUSIONS: Plasma SFAs and several of their subtypes are inversely associated with lean mass and muscle strength in adults.