Sarcopenia is characterised by a progressive loss of skeletal muscle mass and physical
function as well as related metabolic disturbances. While fibre-rich diets can influence metabolic
health outcomes, the impact on skeletal muscle mass and function is yet to be determined, and the
moderating eects by physical activity (PA) need to be considered. The aim of the present study was
to examine links between fibre intake, skeletal muscle mass and physical function in a cohort of older
adults from the NU-AGE study. In 981 older adults (71 4 years, 58% female), physical function was
assessed using the short-physical performance battery test and handgrip strength. Skeletal muscle
mass index (SMI) was derived using dual-energy X-ray absorptiometry (DXA). Dietary fibre intake
(FI) was assessed by 7-day food record and PA was objectively determined by accelerometery.
General linear models accounting for covariates including PA level, protein intake and metabolic
syndrome (MetS) were used. Women above the median FI had significantly higher SMI compared
to those below, which remained in fully adjusted models (24.7 0.2% vs. 24.2 0.1%, p = 0.011,
2p = 0.012). In men, the same association was only evident in those without MetS (above median
FI: 32.4 0.3% vs. below median FI: 31.3 0.3%, p = 0.005, 2p = 0.035). There was no significant
impact of FI on physical function outcomes. The findings from this study suggest a beneficial impact of FI on skeletal muscle mass in older adults. Importantly, this impact is independent of adherence to
guidelines for protein intake and PA, which further strengthens the potential role of dietary fibre in
preventing sarcopenia. Further experimental work is warranted in order to elucidate the mechanisms
underpinning the action of dietary fibre on the regulation of muscle mass.
