Sarcopenia is a progressive muscle disease, most commonly affecting older individuals, that is categorised by 1) low muscle strength, 2) low muscle quantity or quality, and 3) low physical performance. This disease has several negative implications for human health, including an increased risk of falls, fractures, mobility limitations, and mortality. Sarcopenia also imposes significant burden on healthcare systems. For example, it was estimated that a 10% reduction in the prevalence of sarcopenia would save the US healthcare system $1.1 billion per year. Strategies to reduce the incidence and severity of sarcopenia are therefore of great interest. One potential cause for sarcopenia is long-term, low-level inflammation, which can occur for a number of reasons. One cause may relate to the intestinal wall becoming more susceptible to leaking of toxic particles. Evidence suggests that prebiotic supplementation can reduce this 'leakage'. Galactooligosaccharide (a prebiotic) has previously been shown to reduce inflammation in elderly individuals. The investigators hypothesise that galactooligosaccharide will improve physical function in the elderly indirectly via a reduction in inflammation. This will be a randomised, placebo-controlled, double-blind, parallel study. 32 elderly individuals (65-85 years; mix of males and females) will be randomised to one of two groups, GOS or PLACEBO. The GOS group will supplement their diet with 2.9 g galactooligosaccharide per day for 16 weeks in the form of one sachet (3.65 g) of Bimuno® Daily. The PLACEBO group will supplement with 3.65 g maltodextrin per day for 16 weeks. The study will involve one screening visit and two main trials (baseline and 16 weeks). For the main trials, participants will complete the short physical performance battery (SPPB) and handgrip strength test. In addition, participants will provide blood, urine and faecal samples, as well as a dual-energy x-ray absorptiometry (DEXA), and a peripheral quantitative computed tomography (pQCT) scan.