Highlights In Swedish 70-year-olds, prevalence of probable/confirmed sarcopenia was low (2%). Only moderate-to-vigorous physical activity (MVPA) was associated with reduced sarcopenia. There was no threshold in associations between MVPA bout duration and sarcopenia. Greater MVPA was not associated with increased incidence of 12-month falls.

Summary Sarcopenia and obesity are common conditions in older adults that may have differing effects on falls and fracture risk. This systematic review and meta‐analysis aimed to determine whether older adults with sarcopenic obesity have increased risk of falls and fractures or lower bone mass compared with older adults with sarcopenia, obesity, or neither condition. Twenty‐six studies (n = 37,124) were included in the systematic review and 17 (n = 31,540) were included in the meta‐analysis. Older adults with sarcopenic obesity had lower femoral neck areal bone mineral density (aBMD) compared with those with obesity alone but had higher femoral neck aBMD compared with counterparts with sarcopenia alone (both P < 0.05). Older adults with sarcopenic obesity had higher nonvertebral fracture rates (incidence rate ratio: 1.88; 95% confidence intervals: 1.09, 3.23; based on two studies), compared with those with sarcopenia alone, and also had higher falls risk compared with controls (risk ratio: 1.30; 95% confidence intervals: 1.10, 1.54) and obesity alone (risk ratio: 1.17; 95% confidence intervals: 1.01, 1.36). In conclusion, this systematic review and meta‐analysis has demonstrated that older adults with sarcopenic obesity are at increased risk of adverse musculoskeletal outcomes compared with individuals with obesity, sarcopenia, or neither condition. These data support the need for developing interventions to improve bone health and physical function in this population.

The continuous population increase of older adults with metabolic diseases may contribute to increased prevalence of sarcopenia and obesity and requires advocacy of optimal nutrition treatments to combat their deleterious outcomes. Sarcopenic obesity, characterized by age-induced skeletal-muscle atrophy and increased adiposity, may accelerate functional decline and increase the risk of disability and mortality. In this review, we explore the influence of dietary protein on the gut microbiome and its impact on sarcopenia and obesity. Given the associations between red meat proteins and altered gut microbiota, a combination of plant and animal-based proteins are deemed favorable for gut microbiota eubiosis and muscle-protein synthesis. Additionally, high-protein diets with elevated essential amino-acid concentrations, alongside increased dietary fiber intake, may promote gut microbiota eubiosis, given the metabolic effects derived from short-chain fatty-acid and branched-chain fatty-acid production. In conclusion, a greater abundance of specific gut bacteria associated with increased satiation, protein synthesis, and overall metabolic health may be driven by protein and fiber consumption. This could counteract the development of sarcopenia and obesity and, therefore, represent a novel approach for dietary recommendations based on the gut microbiota profile. However, more human trials utilizing advanced metabolomic techniques to investigate the microbiome and its relationship with macronutrient intake, especially protein, are warranted.