This peer-reviewed Nutrition Journal study (KORA-MRI, Southern Germany) analyzed 294 middle-aged adults (45% women; mean age 56.5 years) using whole-body MRI to quantify skeletal muscle fat (%) and area (cm²), and linked these to habitual intake of carbohydrates, fat, protein, alcohol, and essential amino acids derived from repeated 24‑h recalls + FFQ. Alcohol intake (per +1% of total energy) was associated with higher skeletal muscle fat, particularly in men (β = 0.28% [0.10, 0.45]; p = 0.002). Protein intake showed a tentative inverse association with muscle fat (β = −0.33% [−0.68, 0.01]; p = 0.052). Accounting for total energy and protein, higher intake of several essential amino acids (e.g., leucine) was tentatively linked with lower muscle fat (leucine β = −0.63% [−1.27, 0.01]; p = 0.054). Carbohydrate and fat percentages were not significantly associated with muscle fat after adjustment, and macronutrient shares were not associated with muscle area. Implication: individualized diet adaptations—especially moderating alcohol and ensuring adequate protein/essential amino acids—may improve muscle composition and function in midlife. [146+ source]
Resource type:
Peer review