Sarcopenic obesity (SarcO) is defined as the confluence of reduced muscle mass and function and excess body fat. The scientific community is increasingly recognizing this syndrome, which affects a subgroup of persons across their lifespans and places them at synergistically higher risk of significant medical comorbidity and disability than either sarcopenia or obesity alone. Joint efforts in clinical and research settings are imperative to better understand this syndrome and drive the development of urgently needed future interventions. Herein, we describe the ongoing challenges in defining sarcopenic obesity and the current state of the science regarding its epidemiology and relationship with adverse events. The field has demonstrated an emergence of data over the past decade which we will summarize in this article. While the etiology of sarcopenic obesity is complex, we present data on the underlying pathophysiological mechanisms that are hypothesized to promote its development, including age-related changes in body composition, hormonal changes, chronic inflammation, and genetic predisposition. We describe emerging areas of future research that will likely be needed to advance this nascent field, including changes in clinical infrastructure, an enhanced understanding of the lifecourse, and potential treatments.

Caloric restriction and aerobic and resistance exercise are safe and effective lifestyle interventions for achieving weight loss in the obese older population (>65 years) and may improve physical function and quality of life. However, individual responses are heterogeneous. Our goal was to explore the use of untargeted metabolomics to identify metabolic phenotypes associated with achieving weight loss after a multi-component weight loss intervention. Forty-two older adults with obesity (body mass index, BMI, ≥30 kg/m²) participated in a six-month telehealth-based weight loss intervention. Each received weekly dietitian visits and twice-weekly physical therapist-led group strength training classes with a prescription for aerobic exercise. We categorized responders’ weight loss using a 5% loss of initial body weight as a cutoff. Baseline serum samples were analyzed to determine the variable importance to the projection (VIP) of signals that differentiated the responder status of metabolic profiles. Pathway enrichment analysis was conducted in Metaboanalyst. Baseline data did not differ significantly. Weight loss was 7.2 ± 2.5 kg for the 22 responders, and 2.0 ± 2.0 kg for the 20 non-responders. Mummichog pathway enrichment analysis revealed that perturbations were most significant for caffeine and caffeine-related metabolism (p = 0.00028). Caffeine and related metabolites, which were all increased in responders, included 1,3,7-trimethylxanthine (VIP = 2.0, p = 0.033, fold change (FC) = 1.9), theophylline (VIP = 2.0, p = 0.024, FC = 1.8), paraxanthine (VIP = 2.0, p = 0.028, FC = 1.8), 1-methylxanthine (VIP = 1.9, p = 0.023, FC = 2.2), 5-acetylamino-6-amino-3-methyluracil (VIP = 2.2, p = 0.025, FC = 2.2), 1,3-dimethyl uric acid (VIP = 2.1, p = 0.023, FC = 2.3), and 1,7-dimethyl uric acid (VIP = 2.0, p = 0.035, FC = 2.2). Increased levels of phytochemicals and microbiome-related metabolites were also found in responders compared to non-responders. In this pilot weight loss intervention, older adults with obesity and evidence of significant enrichment for caffeine metabolism were more likely to achieve ≥5% weight loss. Further studies are needed to examine these associations in prospective cohorts and larger randomized trials.

Background: Frailty is a geriatric syndrome of significant public health concern that causes vulnerability to physiologic stressors and an increased risk of mortality and hospitalizations. Dietary intake and quality are contributing factors to the development of frailty. The Mediterranean diet is known to be one of the healthiest eating patterns with promising health impacts for prevention. We evaluated the association between Mediterranean diet patterns and frailty status. Methods: We conducted a cross-sectional study using National Health and Nutrition Examination Survey data from 2007 to 2017. We included 7300 participants aged > 60 years who completed the first day of a 24 h diet recall and had full covariate data. We constructed an alternate Mediterranean diet (aMED) score based on the quantity of specific food-group intake and categorized participants to low-, moderate-, and high-adherence groups (aMED adherence scores of 0–2, 3–4, and 5–9, respectively). Using a modified Fried Frailty phenotype (weakness, low physical activity, exhaustion, slow walking speed, and weight loss), participants were categorized as robust (met no criteria), pre-frail (met one or two criteria), and frail (met three or more criteria). Logistic regression evaluated the association of frailty (prefrail/robust as referent) and aMED adherence. Results: Included participants were mainly female (54.5%) and non-Hispanic White (80.0%). The mean (SD) aMED score was 3.6 (1.6) with 45% of participants falling into moderate aMED adherence (26% low adherence, 30% high adherence). Frailty prevalence among participants was 7.1%, with most participants classified as robust (51.0%) or pre-frail (41.9%). Fully adjusted models showed significantly reduced odds of frailty with moderate-adherence and high-adherence groups (odds ratio (95%CI) of 0.71 (0.55, 0.92) and 0.52 (0.36, 0.75), respectively). Conclusions: Mediterranean diet adherence is associated with decreased odds of frailty in older adults. These findings suggest that adherence to a Mediterranean diet may play a critical role in mitigating frailty and its associated conditions. Future research should include longitudinal and interventional studies that can definitively determine the effect of a Mediterranean diet on frailty and what food components provide the greatest benefit.

Dietary assessments are important clinical tools used by Registered Dietitians (RDs). Current methods pose barriers to accurately assess the nutritional intake of older adults due to age-related increases in risk for cognitive decline and more complex health histories. Our qualitative study explored whether implementing Voice assistant systems (VAS) could improve current dietary recall from the perspective of 20 RDs. RDs believed the implementing VAS in dietary assessments of older adults could potentially improve patient accuracy in reporting food intake, recalling portion sizes, and increasing patient-provider efficiency during clinic visits. RDs reported that low technology literacy in older adults could be a barrier to implementation. Our study provides a better understanding of how VAS can better meet the needs of both older adults and RDs in managing and assessing dietary intake.

Background: The role of protein in glucose homeostasis has demonstrated conflicting results. However, little research exists on its impact following weight loss. This study examined the impact of protein supplementation on glucose homeostasis in older adults >65 years with obesity seeking to lose weight. Methods: A 12-week, nonrandomized, parallel group intervention of protein (PG) and nonprotein (NPG) arms for 28 older rural adults (body mass index (BMI) ≥ 30 kg/m²) was conducted at a community aging center. Both groups received twice weekly physical therapist-led group strength training classes. The PG consumed a whey protein supplement three times per week, post-strength training. Primary outcomes included pre/post-fasting glucose, insulin, inflammatory markers, and homeostasis model assessment of insulin resistance (HOMA-IR). Results: Mean age and baseline BMI were 72.9 ± 4.4 years and 37.6 ± 6.9 kg/m² in the PG and 73.0 ± 6.3 and 36.6 ± 5.5 kg/m² in the NPG, respectively. Mean weight loss was −3.45 ± 2.86 kg in the PG and −5.79 ± 3.08 kg in the NPG (p < 0.001). There was a smaller decrease in pre- vs. post-fasting glucose levels (PG: −4 mg ± 13.9 vs. NPG: −12.2 ± 25.8 mg/dL; p = 0.10), insulin (−7.92 ± 28.08 vs. −46.7 ± 60.8 pmol/L; p = 0.01), and HOMA-IR (−0.18 ± 0.64 vs. −1.08 ± 1.50; p = 0.02) in the PG compared to the NPG. Conclusions: Protein supplementation during weight loss demonstrated a smaller decrease in insulin resistance compared to the NPG, suggesting protein may potentially mitigate beneficial effects of exercise on glucose homeostasis.