Ageing involves significant changes in skeletal muscle mass and its functioning. This study aimed to identify the major nutrient patterns (NPs) present in a sample of adult Polish women and evaluate their associations with the skeletal muscle mass index (SMI). A cross-sectional study initially recruited 527 women, and a final analysis was carried out on 275 women aged 32-60 years. Nutrient intake was assessed using fourteen repetitions of 24-hour dietary recall. NPs were derived using principal component analysis. Associations between adherence to NPs and the SMI were evaluated using linear regression models. Three NPs were identified: 'Animal Protein-Vitamins', 'Fibre-Plant Protein-Minerals' and 'Fats'. In the adjusted model, the upper tertile compared to the bottom tertile of the 'Animal Protein-Vitamins' NP was related to a higher SMI (β = 0.123 95% CI: 0.019; 0.227; P for 1-SD increase of NP score = 0.009). No associations between the SMI and the 'Fibre-Plant Protein-Minerals' and 'Fats' NPs were observed. Our results indicate that high adherence to animal product-rich patterns might be related to higher muscle mass in adult women. Research on the influence of dietary and nutrient patterns on the quality of muscle tissue may contribute to the setting of guidelines for nutritional protection of skeletal muscle with ageing and, consequently, dietary recommendations that would improve the quality of women's lives at the later stage of life.