Protein supplementation improves muscle mass and physical performance in undernourished prefrail and frail elderly subjects: a randomized, double-blind, placebo-controlled trial

Sarcopenia: an Aging Perspective and Management Options

There is no doubt that sarcopenia is one of the most defining characteristics of aging that negatively impacts the people's health and quality of life. The condition is characterized by the progressive and generalized loss of muscle mass and strength, affecting physical performance. It is part of aging but can be exacerbated by pathophysiological conditions like cancer and several factors such as a sedentary lifestyle, poor nutrition, chronic diseases, falls and immobilization. Numerous cellular mechanisms have been implicated in its pathogenesis, including hormonal changes, mitochondrial dysfunctions, altered apoptotic and autophagic signaling, muscle fiber composition, and inflammatory pathways. To prevent sarcopenia, exercise is one of the most effective strategies as it has a strong influence on both anabolic and catabolic muscle pathways and helps improve skeletal muscle function. A well-rounded, multicomponent exercise program that targets muscle strength, aerobic capacity, and balance is recommended for optimal results. While nutrition is essential for muscle maintenance, relying solely on dietary interventions is unlikely to fully address sarcopenia. Therefore, a combination of adequate nutrition and regular exercise is recommended to promote muscle health and function. The purpose of this study is to review sarcopenia from an aging viewpoint and discuss the role of exercise and nutrition as prevention and management options.

Effectiveness of Protein-enriched oral nutritional supplements on muscle function in middle-aged and elderly women: A randomized controlled trial

OBJECTIVES

This study evaluated the effects of protein-enriched oral nutritional supplementation (ONS) consumption for 12 weeks on muscle mass, muscular strength, and function in middle-aged and elderly women.

DESIGN

A single-center, double-blind, randomized controlled trial PARTICIPANTS: This study was conducted with 70 healthy female participants aged 50-80.

INTERVENTION AND MEASUREMENTS

Participants were instructed to incorporate two daily packs of either the test ONS (Nucare Active, Daesang Wellife Corp., Seoul, Republic of Korea; 200 kcal/pack, 23 g carbohydrate, 6 g fat, and 15 g protein including branched chain amino acids or placebo ONS (200 kcal/pack, 33 g carbohydrate, 8 g fat, and 1 g protein) into their routine for 12 weeks while maintaining their regular lifestyle. The primary outcome was lean body mass (LBM), while secondary outcomes included muscular strength, physical performance ability, inflammatory markers, and body fat mass (FM).

RESULTS

Sixty-four participants (33 in the test group, 31 in the placebo group; mean ± SD age, [test] 63.06 ± 5.51 years, [placebo] 63.29 ± 3.28 years, p = 0.839) completed the 12-week protocol. The test group exhibited a higher percentage change in LBM than the placebo group (0.26 % [95%CI: -0.27, 0.78] vs. -0.47 % [95%CI: -0.81, -0.13]; p = 0.020). The placebo group experienced a significant increase in FM (38.15 % [95%CI: 36.62, 39.69] to 38.67 % [95%CI: 37.14, 40.21]; p < 0.01). The difference in the changes in LBM/BMI and FM/BMI between the two groups was also visually distinct. There were no significant differences between the two groups in terms of muscular strength, physical performance ability, or inflammatory markers.

CONCLUSIONS

Protein-enriched ONS helped maintain LBM and prevent FM gain in middle-aged and elderly females. This suggests its potential role in preventing frailty and musculoskeletal disorders associated with female aging.

Associations of diet patterns with successful aging, longevity, and extreme longevity: a prospective cohort study among Chinese adults 65 years or older

PURPOSE

The role of dietary patterns in overall health and longevity among the elderly has not been comprehensively evaluated. We investigated the associations between multiple dietary indices and successful aging, longevity, and extreme longevity among older individuals, aiming to explore appropriate dietary patterns for the older Chinese population.

METHODS

A food frequency questionnaire was used to construct seven dietary indices: plant-based dietary index (PDI), healthful plant-based dietary index (hPDI), unhealthful plant-based dietary index (uPDI), animal-based dietary index (ADI), dietary diversity index (DDI), protein-enriched dietary diversity index (PEDDI), and anti-inflammatory dietary diversity index (AIDDI). When analyzing the associations between dietary indices and successful aging, longevity, and extreme longevity, logistic regression models or Cox proportional hazards models were employed. Followed by restricted cubic splines to examine the non-linear associations.

RESULTS

Each SD increment in PEDDI was associated with a 20% higher probability of successful aging (OR = 1.20, 95% CI: 1.06-1.36). One SD increment in PEDDI was related to a 26% higher probability of longevity (HR = 1.26, 95% CI: 1.14-1.39). Individuals in the top tertile group of PEDDI had a higher probability of achieving extreme longevity compared to those in the bottom tertile group of PEDDI (OR = 1.83, 95% CI:1.01-3.30).

CONCLUSIONS

For older adults in China, greater attention should be given to dietary patterns rich in protein, as higher PEDDI scores were statistically associated with promoting successful aging, longevity, and extreme longevity.

Effect of protein and amino acids supplements on muscle strength and physical performance: A scoping review of randomized controlled trials

Protein and amino acid supplementation is an effective intervention that significantly enhances physical function and reduces frailty and sarcopenia in older adults. This scoping review aims to map and synthesize the available evidence on the effects of various types of protein and amino acid supplementation in this population. Following the PRISMA-ScR guidelines, we conducted a literature search to identify clinical trials examining the effects of protein and amino acid supplementation, with or without physical exercise, on muscle strength, physical performance, and body composition in healthy, frail, or sarcopenic older adults. Our analysis of 80 trials with a total of 5290 participants examines the evidence for the effectiveness of protein supplementation in enhancing muscle strength and body composition. Whey protein, creatine, milk protein, leucine, essential amino acids, and soy protein were the most used types of protein, and our findings indicate that whey protein, creatine, and milk protein yield the best results when used in conjunction with resistance training. Additionally, leucine and milk protein have shown the potential to enhance body composition even without concurrent resistance training. In conclusion, studies on the effectiveness of whey protein in improving muscle strength and body composition in older adults with resistance training are inconsistent. More research is required to explore the potential benefits of soy and leucine-enriched supplements. Protein supplementation's impact on physical performance remains inconclusive. Further studies are needed to determine the effects of protein types and supplementation on muscle-related parameters in older adults.

Effect of individually tailored nutritional counseling on frailty status in older adults with protein-energy malnutrition or risk of it: an intervention study among home care clients

BACKGROUND

Frailty and protein-energy malnutrition (PEM) are common in older home care clients. In this study, we evaluate the effect of individually tailored dietary counseling on frailty status among home care clients with PEM or its risk aged 75 or older with a follow-up of six months.

METHODS

This intervention study is part of the non-randomized population-based Nutrition, Oral Health and Medication (NutOrMed) study in Finland. The frailty was assessed using the abbreviated Comprehensive Geriatric Assessment (aCGA) and included 15 questions from three different domains: cognitive status (MMSE), functional status (ADL, IADL) and depression (GDS-15). The study population consisted of persons with PEM or its risk (intervention group n = 90, control group n = 55). PEM or its risk was defined by MNA score <24 and/or plasma albumin <35 g/l. Registered nutritionist gave individually tailored nutritional counseling for participants at the baseline and nutritional treatment included conventional food items.

RESULTS

The mean age was 83.9 in the intervention and 84.3 in the control group. At the baseline frailty prevalence was 74.4% (n = 67) and after six-month 61.1% (n = 55) in the intervention group and, respectively 74.5% (n = 41) and 80.0% (n = 44) in the control group. The intervention decreased significantly (p < 0.001) the prevalence of frailty in the intervention group, while it increased in the control group.

CONCLUSIONS

Individually tailored nutritional counseling reduces the prevalence of frailty among vulnerable home care clients with PEM or its risk. In the nutritional treatment of frailty, adequate intake of protein and energy should be a cornerstone of treatment.

State-of-the-Art and Future Challenges for Nutritional Interventions in Facioscapulohumeral Dystrophy: A Narrative Review

Facioscapulohumeral dystrophy (FSHD), the second most common inherited muscular dystrophy in adulthood, is characterized by progressive muscle loss, accompanied by an increase in fat mass. Beyond these alterations in body composition, which contribute to the risk of sarcopenic obesity, FSHD is associated with systemic inflammation and oxidative stress. These interconnected mechanisms may worsen muscle atrophy, leading to a decline in physical efficiency and quality of life. While the therapeutic benefits of physical therapy and exercise have been investigated, the impact of dietary interventions remains underexplored. Given the established role of nutrition in managing various chronic diseases, there is growing interest in understanding how it might influence the clinical management of FSHD. By addressing current gaps in the literature, this review aims to investigate the potential role of dietary patterns and specific nutrients in modulating muscle metabolism within the context of FSHD. Some studies have indicated various compounds (flavonoids, curcumin, L-carnitine, coenzyme Q10, and omega-3), vitamins (C and E), and minerals (zinc and selenium) with antioxidant and anti-inflammatory properties as promising treatment strategies for FSHD. Instead, few data regarding the effects of proteins and creatine supplementation are available. Furthermore, the potential benefits of essentials amino acids, β-hydroxy-β-methylbutyrate, and vitamin D in contrasting muscle atrophy and enhancing muscle function remain unexplored. Despite these preliminary findings, the existing body of evidence is limited. Identifying novel therapeutic strategies to complement existing treatments could provide a more comprehensive management framework, aimed at improving the long-term health outcomes and quality of life of FSHD patients.

Dietary protein requirements of older adults with sarcopenia determined by the indicator amino acid oxidation technology

Background

Although protein supplementation may be desirable in the management of sarcopenia, the appropriate protein requirements for older adults with sarcopenia are presently unclear.

Objective

The aim of this study was to determine the protein requirements of older adults (65-81 year) with sarcopenia by using the indicator amino acid oxidation (IAAO) technology.

Methods

Nine older adults with sarcopenia (four male participants and five female participants) participated in the study, with protein intakes ranging from 0.1 to 1.8 g/(kg·d). Each participant consumed an adapted diet with a protein level of 1.0 g/(kg·d) and 1.7 resting energy expenditure (REE) for 2 day. Day 3 was the oxidation day of the study. Diets that delivered energy at a 1.5 × REE were isocaloric. The amounts of phenylalanine and tyrosine maintained at a constant across intakes. Therefore, phenylalanine and tyrosine were added to the protein doses of 0.1-1.5 g/kg, which was based on the highest dose of lactalbumin content [1.8 g/(kg·d)]. Applying a non-linear mixed-effects model analysis of F13CO2, the protein requirement was determined by identifying the breakpoint in the F13CO2 data with graded amounts of dietary protein.

Results

The mean estimated average requirement (EAR) and recommended nutrient intake (RNI) of protein for older adults with sarcopenia were 1.21 (95% CI: 0.95, 1.46) and 1.54 (95% CI: 1.13, 1.95) g/(kg·d), respectively.

Conclusions

To our knowledge, this is the first study of protein intake in older adults with sarcopenia and indicates that older adults with sarcopenia may require a higher intake of dietary protein.

Clinical trial registration

http://www.chictr.org.cn, ChiCTR2200061383.

Cognitive Frailty and Aging: Clinical Characteristics, Pathophysiological Mechanisms, and Potential Prevention Strategies

Frailty has been conceptualized not only as a physical disease, but also as a multidomain entity that encompasses a multimorbid status, disability, cognitive impairment, psychosocial risk factors, and even geriatric syndromes. In addition to physical ailments and depending on the diagnostic model. Standardized neuropsychological tests can identify cognitive deficiencies along with mild cognitive impairment, a pre-dementia stage characterized by memory and/or other cognitive domain impairments with relatively preserved instrumental activities of daily living. Hence, the possibility of cognitive frailty (CF), a construct that refers to physical frailty in concurrence with non-dementia cognitive decline, is proposed. The estimated prevalence of CF ranges from 10.3 to 42.8%. It is likely that the pathway to overt cognitive impairment, which does not yet involve physical function, begins with the asymptomatic early accumulation of progressive brain damage. Thus, timely detection strategies that target the initial phases of CF are warranted. The pathophysiological components of CF include dysregulation of the hypothalamic-pituitary axis stress response, imbalance in energy metabolism, impaired cardiovascular function, mitochondrial deterioration, and vascular age-related arterial stiffness. Changes that contribute to this disease can also occur at the cellular level, including overexpression of the renin-angiotensin-aldosterone system, activation of proinflammatory pathways, endothelial dysfunction, reduced nitric oxide production, and increased oxidative stress. Non-pharmacological interventions, that range from dietary and nutritional counseling to psychosocial therapy, are currently the main approaches. Both cognitive and physical training programs are considered to be the best researched and most useful multidomain interventions. Clinicians recognize CF as a valid concept that warrants prevention and treatment strategies supported by current research.

Association of Protein Intake with Sarcopenia and Related Indicators Among Korean Older Adults: A Systematic Review and Meta-Analysis

OBJECTIVES

Due to variations in the standards for optimal protein intake and conflicting results across studies for Korean older adults, this study aimed to quantitatively integrate existing research on the association of protein intake with sarcopenia and related indicators in Koreans aged 65 and older through meta-analysis.

METHODS

A total of 23 studies were selected according to the study selection criteria (PICOS). Sixteen cross-sectional studies, 5 randomized controlled trials (RCTs), and 2 non-RCTs were included in the review, with 9 out of 23 studies included in the meta-analysis. We used fixed-effects models and performed subgroup and sensitivity analyses.

RESULTS

A meta-analysis found that the risk of sarcopenia was significantly higher in the <0.8 g/kg/day protein intake group compared to the 0.8-1.2 g/kg/day and ≥1.2 g/kg/day groups, with odds ratios (ORs) of 1.25 (95% confidence interval (CI), 1.10 to 1.42; I2 = 55%) and 1.79 (95% CI, 1.53 to 2.10; I2 = 71%), respectively. For low hand grip strength (HGS), the risk was higher in the <0.8 g/kg/day group compared to the 0.8-1.2 g/kg/day or ≥1.2 g/kg/day groups (OR 1.31; 95% CI, 1.03 to 1.65; I2 = 28%). No significant associations were found with other sarcopenia indicators, such as skeletal muscle mass, short physical performance battery score, balance test, gait speed, and timed up-and-go test.

CONCLUSIONS

Lower protein intake is associated with a higher risk of sarcopenia and low HGS in Korean older adults. To establish protein intake recommendations for the prevention and management of sarcopenia in this population, further well-designed RCTs incorporating both protein supplementation and resistance training are necessary.

Exercise with weight vest plus chicken protein supplementation delayed muscle and bone loss in older female adults

PURPOSE

This study examined the effects of moderate-to-heavy exercise training combined with weighted vest and chicken protein supplementation in older adult females.

METHODS

Fifty-two female participants, 60-79 yearsold, were randomly divided into three groups: control (non-exercise) (CON), exercise with weighted vest (WV), and exercise with weighted vest and protein supplementation (3 g of protein daily; WVP).A ll participants performed brisk walking and strengthening exercises for 50 min/day, three times/week, for 8 weeks. Muscle mass, bone mineral content, T-score, and physical performance were measured.

RESULTS

The WVP group demonstrated a substantial increase in thoracic spine bone mineral content (8.4 ± 7.7 g, p = 0.001), and total body lean mass (0.2 ± 1.0 kg) compared with that in the other two groups. The CON and WV groups showed a decrease in thoracic spine bone mineral content (CON= -1.8 ± 1.8, WV= -3.9 ± 0.1 g) and total body lean mass (CON= -0.7 ± 0.9, WV= -0.8 ± 0.9 kg) compared with those in the WVP group. The WVP and WV groups had increased T-score (WVP= 0.01 ± 0.16, WV= 0.02 ± 0.18) when compared with that of the CON group (-0.19 ± 0.12). Both the WV and WVP groups displayed improved physical performance compared with that of the CON group.

CONCLUSION

Combined exercise with either a weighted vest or protein supplementation proved to be effective in protecting against trunk bone and muscle mass loss, and improving physical fitness in older female adults.

Association of dietary inflammatory index with sarcopenia in patients with Metabolic dysfunction-associated fatty liver disease: a cross-sectional study

Background

Sarcopenia is a common complication of fatty liver, and sarcopenia increases the risk of advanced liver fibrosis in patients with Metabolic dysfunction-associated fatty liver disease (MAFLD). Chronic inflammation is the crucial link between sarcopenia and fatty liver. An anti-inflammatory diet is expected to be an essential measure to prevent sarcopenia in patients with fatty liver, and the dietary inflammatory index (DII) is a crucial tool for assessing the inflammatory potential of diets. However, the relationship between DII and sarcopenia in patients with fatty liver is unclear.

Objective

This study investigated the correlation between the dietary inflammatory index (DII) and sarcopenia in patients with Metabolic dysfunction-associated fatty liver disease (MAFLD).

Methods

Data for this study were obtained from the National Health and Nutrition Examination Survey (NHANES) 2017-2018, with 917 patients with MAFLD participating in the study. Participants were divided into three groups based on DII tertiles: group T1 (n = 305), group T2 (n = 306), and group T3 (n = 306), and binary logistic regression was used to assess the relationship between DII and sarcopenia with stratified analyses based on the weights recommended by the NHANES and multivariate linear regression was used to evaluate the association of DII with total appendicular lean mass.

Results

After adjusting for all confounders, DII was significantly and positively associated with the risk of sarcopenia in women [OR: 1.61, 95% CI: (1.226, 2.06), p < 0.001]. The risk of sarcopenia was higher in the T3 group compared to the T1 group [OR: 4.04, 95% CI: (1.66, 9.84), p = 0.002]. DII was negatively associated with appendicular lean mass adjusted for body mass index in both men and women.

Conclusion

DII was significantly associated with the risk of sarcopenia in female patients with MAFLD, with higher DII scores related to a higher risk of sarcopenia. Higher DII scores related to a higher risk of sarcopenia in men with significant fibrosis.

Daily supplementation of lesser mealworm protein for 11-weeks increases skeletal muscle mass in physically active older adults

BACKGROUND

Adequate protein intake is important to maintain skeletal muscle mass in older adults and to prevent sarcopenia. Insect-based supplements were recently introduced to the market as an environmentally friendly protein alternative. We examined the effect of daily supplementation of lesser mealworm (Alphitobius diaperinus) protein for 11 consecutive weeks on muscle mass and muscle strength in older adults.

METHODS

In this randomized controlled trial, 70 physically active older adults (>60 years) were randomly allocated to three groups: (I) lesser mealworm protein, (II) whey protein or (III) iso-caloric placebo. Participants received 11 weeks of supplements two times a day (30 gram/day). Muscle mass, fat mass, leg muscle strength and handgrip strength were measured at baseline and after 11 weeks of supplementation.

RESULTS

Of the 70 participants, 59 completed the supplementation period (mealworm n = 16; whey n = 23; iso-caloric placebo n = 20). Overall, skeletal muscle mass increased from 29.0 ± 6.2 kg to 29.3 ± 6.1 kg, with a significantly more profound increase in the lesser mealworm group (+0.67 [0.20-1.14] kg) compared to the whey (+0.03 [-0.20 - 0.28] kg) and placebo group (+0.30 [0.03 - 0.63] kg, Pgroup*time = 0.030). Fat mass and maximum handgrip strength decreased over time, whereas one-repetition maximum (1RM) leg muscle strength did not change pre- versus post-intervention. No group differences, nor interaction effects, were observed for fat mass, leg muscle strength and handgrip strength CONCLUSION: 11-weeks of lesser mealworm protein supplementation induced an increase in skeletal muscle mass compared to whey protein supplementation and iso-caloric placebo in physically active older adults. No differences among groups were observed for changes in muscle strength.

Prevalence and risk factors of frailty in older adults with diabetes: A systematic review and meta-analysis

OBJECTIVE

This systematic review and meta-analysis aimed to evaluate the prevalence of frailty and pre-frailty in older adults with diabetes; and to identify the risk factors associated with frailty in this population.

DESIGN

Systematic review and meta-analysis.

PARTICIPANTS

24,332 people aged 60 years and older with diabetes.

METHODS

Six databases were searched (PubMed, Embase, the Cochrane Library, Web of Science, China Knowledge Resource Integrated Database, and Chinese Biomedical Database) up to 15 January 2024. Random effects models were used in instances of significant heterogeneity. Subgroup analysis and meta-regression were conducted to identify the potential source of heterogeneity. The Agency for Healthcare Research and Quality (AHRQ) and the Newcastle-Ottawa Scale (NOS) were applied to assess the quality of included studies.

RESULTS

3,195 abstracts were screened, and 39 full-text studies were included. In 39 studies with 24,332 older people with diabetes, the pooled prevalence of frailty among older adults with diabetes was 30.0% (95% CI: 23.6%-36.7%). Among the twenty-one studies involving 7,922 older people with diabetes, the pooled prevalence of pre-frailty was 45.1% (95% CI: 38.5%-51.8%). The following risk factors were associated with frailty among older adults with diabetes: older age (OR = 1.08, 95% CI: 1.04-1.13, p<0.05), high HbA1c (OR = 2.14, 95% CI: 1.30-3.50, p<0.001), and less exercise (OR = 3.11, 95% CI: 1.36-7.12, p<0.001).

CONCLUSIONS

This suggests that clinical care providers should be vigilant in identifying frailty and risk factors of frailty while screening for and intervening in older adults with diabetes. However, there are not enough studies to identify comprehensive risk factors of frailty in older adults with diabetes.

TRIAL REGISTRATION

PROSPERO registration number: CRD42023470933.

Nutritional management interventions and multi-dimensional outcomes in frail and pre-frail older adults: A systematic review and meta-analysis

BACKGROUND

Frailty, a prevalent geriatric syndrome, presents challenges exacerbated by malnutrition. Nutritional Management Interventions (NMIs) offer hope in frailty reversal, necessitating exploration of their multi-dimensional outcomes.

OBJECTIVES

Assess NMIs' impact on frail and pre-frail older adults across diverse outcomes.

METHODS

A systematic review and meta-analysis of 13 studies (2012-2023) evaluated NMIs' effects on physical, dietary, psychological, and frailty aspects. Literature quality was assessed, and data analyzed with Review Manager 5.3.

RESULTS

A total of 13 studies involving participants were included in the analysis. Participants numbered 968, with the intervention group averaging 77.05±0.77 years and the control group 78.75±0.8 years. Compared to control groups,NMIs significantly increased body weight (SMD = 0.26, P = 0.03) and improved gait speed (SMD = 0.18, P = 0.03). Protein intake showed significance for interventions≤12 weeks (SMD = 1.04, P < 0.001). No significant differences in energy intake (SMD = 0.20, P = 0.60), but >12 weeks NMIs reduced energy intake (SMD = -0.73, P = 0.006). No significant differences in depressive symptoms, frailty scores, BMI, TUG, Handgrip Strength, or SPPB.

CONCLUSION

This meta-analysis underscores NMIs' potential benefits for frail and pre-frail older adults. Personalized, multidimensional interventions are recommended despite study limitations, emphasizing extended interventions and diverse assessments for holistic care.

Effectiveness of whey protein supplementation on muscle strength and physical performance of older adults: A systematic review and meta-analysis of randomized clinical trials

BACKGROUND

The efficacy of whey protein supplement (WPS) in improving muscle strength, physical performance, and body composition in older adults has been widely promoted. However, the results of randomized clinical trials in this regard have been inconsistent. We aimed to determine the impact of WPS, compared to a placebo, during or without training on muscle strength, physical function, and body composition in older adults.

METHODS

Randomized controlled trials were thoroughly searched using PubMed, EMBASE, the Cochrane Library Database, and Scopus databases up to June 2024. The analysis focused on key parameters such as handgrip strength (HS), leg press, knee extension, gait speed (GS), 6-min walking test (6MWT), Timed-up and go test (TUG), lean body mass (LBM), fat mass (FM), and appendicular skeletal muscle mass (ASM). A pooled effect size was calculated using a random-effects model based on standardized mean differences (SMD).

RESULTS

Thirty studies involving 2105 participants aged 60 and older met the inclusion criteria. The meta-analysis of 26 RCTs showed no significant positive effect of WPS on HS (n = 11, SMD: 0.18; 95% CI: -0.13, 0.49; I2 = 69%), 6MWT (n = 5, SMD: -0.08; 95%CI: -0.31, 0.16; I2 = 0%), GS test (n = 4, SMD: -0.08; 95%CI: -0.43, 0.28; I2 = 36%), TUG test (n = 9, SMD: 0.0, 95% CI -0.15, 0.14; I2 = 0%), LBM (n = 11, SMD: 0.02; 95%CI: -0.13, 0.17; I2 = 0%), FM (n = 15, SMD: -0.04; 95%CI: -0.18, 0.10; I2 = 0%). However, ASM significantly improved after WPS consumption but with high heterogeneity (n = 2, SMD: 0.39; 95%CI: 0.28, 0.51; I2 = 69%). In interventions incorporating RE, statistically significant positive effects of WPS on lower body strength were observed (n = 11, SMD: 0.25; 95%CI: 0.05, 0.45; I2 = 0%).

CONCLUSION

The present meta-analysis indicates that WPS, when combined with resistance training (RT), can enhance lower body strength but does not seem to have a significant beneficial effect on handgrip strength, physical performance, or body composition. Further large-scale studies are necessary to confirm these findings and elucidate the potential benefits of WPS in this population.

Oral Protein Supplements Might Improve Nutritional Status and Quality of Life in Elderly Patients after Standard Pancreatic Resection

Elderly patients who undergo pancreaticoduodenectomy (PPPD) or distal pancreatectomy (DP) experience not only a reduction in protein intake but also a decrease in protease secretion, leading to impaired protein digestion and absorption. This increases the risk of malnutrition and creates a dual burden of sarcopenia. This randomized, double-blind, placebo-controlled trial examined the impact of protein supplements on the nutritional status and quality of life (QoL) of elderly patients after PPPD and DP surgeries. For six weeks, the case group (CG; n = 23) consumed protein supplements containing 18 g of protein daily, while the placebo group (PG; n = 18) consumed a placebo with the same amount of carbohydrate. In elderly patients where protein digestion and intake were compromised, the CG showed significantly higher protein intake (77.3 ± 5.3 g vs. 56.7 ± 6.0 g, p = 0.049), improved QoL, better nutritional status, and faster walking speed compared to the PG. Protein intake was positively correlated with muscle mass and phase angle. Protein supplementation may not only increase protein intake but also improve clinical outcomes such as walking speed, nutritional status, and QoL in elderly post-surgical patients at high risk of sarcopenia. Further studies are needed to determine the optimal dosage and long-term effects.

The effect of dose, frequency, and timing of protein supplementation on muscle mass in older adults: A systematic review and meta-analysis

Protein supplementation has shown to improve muscle mass in older adults. However, its effect may be influenced by supplementation dose, frequency and timing. This systematic review aimed to assess the effect of dose, frequency and timing of protein supplementation on muscle mass in older adults. Five databases were systematically searched from inception to 14 March 2023, for randomised controlled trials investigating the effect of protein supplementation on muscle mass in adults aged ≥65 years. Random effects meta-analyses were performed, stratified by population. Subgroups were created for dose (≥30 g, <30 g/day), frequency (once, twice, three times/day) and timing of supplementation (at breakfast, breakfast and lunch, breakfast and dinner, all meals, between meals). Heterogeneity within and between subgroups was assessed using I2 and Cochran Q statistics respectively. Thirty-eight articles were included describing community-dwelling (28 articles, n=3204, 74.6±3.4 years, 62.8 % female), hospitalised (8 articles, n=590, 77.0±3.7 years, 50.3 % female) and institutionalised populations (2 articles, n=156, 85.7±1.2 years, 71.2 % female). Protein supplementation showed a positive effect on muscle mass in community-dwelling older adults (standardised mean difference 0.116; 95 % confidence interval 0.032-0.200 kg, p=0.007, I2=15.3 %) but the effect did not differ between subgroups of dose, frequency and timing (Q=0.056, 0.569 and 3.084 respectively, p>0.05). Data including hospitalised and institutionalised populations were limited. Protein supplementation improves muscle mass in community-dwelling older adults, but its dose, frequency or timing does not significantly influence the effect.

Lactiplantibacillus plantarum LM1001 Improves Digestibility of Branched-Chain Amino Acids in Whey Proteins and Promotes Myogenesis in C2C12 Myotubes

Lactiplantibacillus plantarum is a valuable potential probiotic species with various proven health-beneficial effects. L. plantarum LM1001 strain was selected among ten strains of L. plantarum based on proteolytic activity on whey proteins. L. plantarum LM1001 produced higher concentrations of total free amino acids and branched-chain amino acids (Ile, Leu, and Val) than other L. plantarum strains. Treatment of C2C12 myotubes with whey protein culture supernatant (1%, 2% and 3%, v/v) using L. plantarum LM1001 significantly increased the expression of myogenic regulatory factors, such as Myf-5, MyoD, and myogenin, reflecting the promotion of myotubes formation (p<0.05). L. plantarum LM1001 displayed β-galactosidase activity but did not produce harmful β-glucuronidase. Thus, the intake of whey protein together with L. plantarum LM1001 has the potential to aid protein digestion and utilization.

Prevention and Treatment of Malnutrition in Older Adults Living in Long-Term Care or the Community: An Evidence-Based Nutrition Practice Guideline

Malnutrition in older adults can decrease quality of life and increase risk of morbidities and mortality. Accurate and timely identification of malnutrition, as well as subsequent implementation of effective interventions, are essential to decrease poor outcomes associated with malnutrition in older adults. The Academy of Nutrition and Dietetics Evidence Analysis Center conducted a systematic review of the literature to develop an evidence-based nutrition practice guideline for the prevention and treatment of malnutrition in older adults. The objective of this guideline was to provide evidence-based recommendations to identify, prevent, or treat protein-energy malnutrition in older adults (mean age ≥65 years) living in long-term care and community settings. This guideline provides 11 nutrition recommendations to inform shared decision making among dietitians, members of the health care team, family members or caregivers, and older adults living in long-term care or the community to prevent or treat malnutrition. Topics include dietitian effectiveness, nutrition assessment tools, oral nutrition supplements, food fortification, and home-delivered and congregate meals. Guideline implementation should include consideration of the importance of comprehensive individualized nutrition care for older adults. Future research is needed to address gaps that were identified related to the validity, reliability, and feasibility of nutrition assessment tools, as well as the effectiveness of dietitian interventions on outcomes of interest in older adults living in long-term care and the community.

Dietary protein and amino acid intakes for mitigating sarcopenia in humans

Adult humans generally experience a 0.5-1%/year loss in whole-body skeletal muscle mass and a reduction of muscle strength by 1.5-5%/year beginning at the age of 50 years. This results in sarcopenia (aging-related progressive losses of skeletal muscle mass and strength) that affects 10-16% of adults aged ≥ 60 years worldwide. Concentrations of some amino acids (AAs) such as branched-chain AAs, arginine, glutamine, glycine, and serine are reduced in the plasma of older than young adults likely due to insufficient protein intake, reduced protein digestibility, and increased AA catabolism by the portal-drained viscera. Acute, short-term, or long-term administration of some of these AAs or a mixture of proteinogenic AAs can enhance blood flow to skeletal muscle, activate the mechanistic target of rapamycin cell signaling pathway for the initiation of muscle protein synthesis, and modulate the metabolic activity of the muscle. In addition, some AA metabolites such as taurine, β-alanine, carnosine, and creatine have similar physiological effects on improving muscle mass and function in older adults. Long-term adequate intakes of protein and the AA metabolites can aid in mitigating sarcopenia in elderly adults. Appropriate combinations of animal- and plant-sourced foods are most desirable to maintain proper dietary AA balance.

The intersection of frailty and metabolism

On average, aging is associated with unfavorable changes in cellular metabolism, which are the processes involved in the storage and expenditure of energy. However, metabolic dysregulation may not occur to the same extent in all older individuals as people age at different rates. Those who are aging rapidly are at increased risk of adverse health outcomes and are said to be "frail." Here, we explore the links between frailty and metabolism, including metabolic contributors and consequences of frailty. We examine how metabolic diseases may modify the degree of frailty in old age and suggest that frailty may predispose toward metabolic disease. Metabolic interventions that can mitigate the degree of frailty in people are reviewed. New treatment strategies developed in animal models that are poised for translation to humans are also considered. We suggest that maintaining a youthful metabolism into older age may be protective against frailty.

Protein Restriction in Metabolic Health: Lessons from Rodent Models

Consumption of protein-rich diets and supplements has been increasingly advocated by individuals seeking to optimize metabolic health and mitigate the effects of aging. Protein intake is postulated to support muscle mass retention and enhance longevity, underscoring its perceived benefits in age-related metabolic regulation. However, emerging evidence presents a paradox; while moderate protein consumption contributes to health maintenance, an excessive intake is associated with an elevated risk of chronic diseases, notably obesity and diabetes. Furthermore, recent studies suggest that reducing the ratio of protein intake to macronutrients improves metabolic parameters and extends lifespan. The aim of this study is to review the current evidence concerning the metabolic effects of protein-restricted diets and their potential mechanisms. Utilizing rodent models, investigations have revealed that protein-restricted diets exert a notable influence over food intake and energy consumption, ultimately leading to body weight loss, depending on the degree of dietary protein restriction. These phenotypic alterations are primarily mediated by the FGF21 signaling pathway, whose activation is likely regulated by ATF4 and the circadian clock. The evidence suggests that protein-restricted diets as an alternative approach to calorie-restricted regimes, particularly in overweight or obese adults. However, more research is needed to determine the optimal level of restriction, duration, and long-term effects of such interventions.

Nutritional Status of the Elderly Residing in a 24-Hour Medical Care Facility After Nutritional Intervention

Malnutrition is a significant issue among elderly individuals in 24-hour care facilities, leading to increased morbidity. The aim of the study was to compare the nutritional status before and after nutritional intervention based on selected indicators of nutritional status among residents of a 24-hour care institution. The study included a group of 104 people aged 65 to 97 years. Nutritional status was assessed before and after the nutritional intervention based on indicators: levels of prealbumin, albumin, transferrin, total lymphocyte count, BMI, and MNA scale. The nutritional intervention consisted of administering oral nutritional supplements (ONS) to patients, regardless of nutritional status. The method of retrospective analysis of patients' medical records was used. Statistical analysis was performed using IBM SPSS Statistics 24 for Windows. Improvements in nutritional status occurred among patients with malnutrition based on MNA and prealbumin indices, and in groups of patients with moderate or mild malnutrition as determined by transferrin, prealbumin and albumin. The mean levels of nutritional indices significantly increased: MNA (p = .001), BMI (p = .001), prealbumin (p = .001), and albumin (p < .001). The use of ONS resulted in better nutritional status parameters based on MNA, albumin and prealbumin. These indices may be predictors of reducing the risk of various disorders among the elderly.

Nutritional Intervention Improves Muscle Mass and Physical Performance in the Elderly in the Community: A Systematic Review and Meta-Analysis

Nutritional supplements have been extensively used as health interventions for the elderly. However, with the spread of COVID-19, no consensus exists on whether nutritional interventions could improve muscle mass and physical activity in community-dwelling older adults. To conduct a systematic review and meta-analysis to explore the effects of different nutritional interventions on muscle mass and physical performance in the elderly, we searched PubMed, Web of Science, Elsevier, and Cochrane databases from their founding dates to December 2023. The meta-analysis was performed using RevMan5.3 software. Only randomized controlled trials (RCTs) were considered, and the overall mean difference (MD) or standardized mean difference (SMD) with 95% confidence interval (CI) was calculated. There were 33 studies comprising 3579 elderly persons meeting the inclusion criteria. Comprehensive analysis suggested that the intervention effect of fat-free mass (FFM), appendix skeletal muscle mass (ASMM), handgrip strength (HGS), gait speed, and short physical performance battery (SPPB) score was higher in the nutritional supplement group than in the control group. The results of subgroup analysis demonstrated that protein supplementation (SMD = 0.82, p < 0.0001) had an optimal effect on ASMM (SMD = 0.89, p < 0.0001) and FFM (MD = 2.09, p < 0.0001) in the elderly. Vitamin D supplementation (SMD = 0.52, p < 0.0001) had a marginal effect on ASMM, and energy supplementation (SMD = 0.39, p = 0.0005) had the lowest effect. Moreover, nutritional interventions had the most significant impact on HGS (MD = 1.06, p < 0.0001) and TUG (MD = 0.14, p < 0.0001) in individuals aged 65-75 years old, with positive effects on FFM (MD = 1.62, p < 0.0001) and HGS (MD = 0.82, p < 0.0001) when compared to healthy elderly individuals, and had greater effect on ASMM (SMD = 0.69, p < 0.0001) than on the elderly with sarcopenia. Nutritional supplements can enhance muscle mass and physical performance in the elderly, while protein is recommended for muscle function. The golden period for implementing nutritional interventions to improve muscle function is before the age of 75 years. However, the impact of nutritional interventions varies with age and population. Given the limited evidence on nutritional interventions, more detailed and high-quality studies are highly warranted in the future.

Dietary protein intake and changes in muscle mass measurements in community-dwelling middle-aged and older adults: A prospective cohort study

BACKGROUND & AIMS

Increasing dietary protein intake can be an efficient strategy to prevent sarcopenia. Nevertheless, due to the discrepancy in the population and their dietary pattern, evidence suggested the effects of dietary protein amount or source on sarcopenia prevention varies. This prospective cohort study investigated the correlation between dietary protein intakes or sources and changes in muscle mass measurements. Additionally, the study explored the link between dietary protein and the prevalence of sarcopenia.

METHODS

Participants aged 40 to 75 were from Guangzhou Nutrition and Health Study (GNHS) 2011-2013 and returned in 2014-2017. Validated 79-item food frequency questionnaires were applied to calculate the amount of total, animal, and plant protein intakes and animal-to-plant protein ratio (APR). The body composition was examined by dual-energy x-ray absorptiometry (DXA) to calculate the appendicular lean mass (ALM) and its index (ASMI). Sarcopenia was diagnosed based on the 2019 Asia Working Group of Sarcopenia's criteria. ANCOVA was utilized to compare the differences of Δ ALM and Δ ASMI across the quartiles of the dietary protein, and linear regression was employed to examine dose-response associations. Multilinear mixed-effect models were employed to evaluate whether protein intake relates to annual changes in ALM and ASMI. Multivariable logistic regressions were performed to analyze the associations between dietary protein and sarcopenia.

RESULTS

In total, 2709 participants during the 3.2-year follow-up period were considered eligible for analysis. Higher dietary protein intakes (total, animal, plant) in both sexes could preserve more ALM and ASMI in a dose-response manner (all P-trend < 0.05). The annual estimated preservations of ASMI were greater in the highest dietary protein intakes (total, animal, plant) quartile than the lowest (0.05-0.13 kg/m2/y, all P < 0.05). In women, the risk of sarcopenia was reduced by 35%-50 % in the highest protein intake (total, animal, plant) quartile than the lowest. The APR did not display any significant associations.

CONCLUSIONS

Higher dietary protein intake, regardless of animal or plant sources, is associated with less muscle loss and a lower prevalence of sarcopenia in middle-aged and older Chinese, particularly women.

CLINICALTRIALS

GOV IDENTIFIER

NCT03179657.

Effects of nutritional supplementation stabilizing muscle mass loss in older patients on hemodiafiltration

BACKGROUND & AIMS

Malnutrition is common in older individuals with end-stage renal disease on maintenance dialysis. Whether nutritional supplementation may improve skeletal muscle mass (SMM) and survival rate in this population is uncertain. We aimed to analyze the effect of a year of nutritional supplementation on muscle mass and survival rate in older patients on hemodiafiltration.

METHODS

In this observational study, older patients (≥65 years old) on maintenance hemodiafiltration were selected to receive nutritional counselling + nutritional supplementation (N = 85, Supp+) or nutritional counselling alone (N = 47, Supp-) and followed for 1 year. The outcomes were a change in SMM and sarcopenia diagnosis. The secondary outcome was 1-year mortality rate. Nutritional parameters included calf circumference, body mass index, anthropometric measurements, subjective global assessment, and handgrip strength (HGS). Data were evaluated using GLM for repeated measures with adjustment for covariates (age and diabetes).

RESULTS

Malnutrition was found in 50.8% of patients. At baseline, patients from the Supp+ group were older and had worse nutritional parameters including hand grip strength, calf circumference, anthropometric findings and sarcopenia (all p values < 0.05). During the follow-up, there was no significant change in sarcopenia (from 50.8% to 58.3%, p = 0.108), and there was a more pronounced decrease in the SMM index in the Supp-group (p = 0.049), with a significant intervention interaction (p = 0.030). Twenty deaths occurred, 7 (35%) in the Supp- and 13 (65%) in the Supp+ group (p = 0.540). SMM index (relative risk 0.90, p = 0.030) and age (relative risk 1.07, p = 0.046) were independently associated with higher mortality rates.

CONCLUSION

Nutritional supplementation in older and malnourished individuals undergoing hemodiafiltration mitigates the loss of the SMM index and benefits survival rate.

Perioperative cognition in association with malnutrition and frailty: a narrative review

Postoperative delirium (POD) is a prevalent clinical entity characterized by reversible fluctuating altered mental status and cognitive impairment with acute and rapid onset a few days after major surgery. Postoperative cognitive decline (POCD) is a more permanent extension of POD characterized by prolonged global cognitive impairment for several months to years after surgery and anesthesia. Both syndromes have been shown to increase morbidity and mortality in postoperative patients making their multiple risk factors targets for optimization. In particular, nutrition imparts a significant and potentially reversible risk factor. Malnutrition and frailty have been linked as risk factors and predictive indicators for POD and less so for POCD. This review aims to outline the association between nutrition and perioperative cognitive outcomes as well as potential interventions such as prehabilitation.

Impact of food-based fortification on nutritional outcomes and acceptability in older adults: systematic literature review

Background

"Do it yourself" (DIY) food-based fortification involves adding fortificants into everyday foods. It is a flexible solution that allows older people with reduced appetite to meet their nutritional needs.

Objectives

The aims of the systematic review are (a) to describe DIY fortified recipes, (b) to evaluate their acceptability, and (c) to evaluate whether they are effective levers to improve nutritional outcomes in older people.

Methods

A systematic search of 3 databases (Web of Science, PubMed, Scopus, last searched on January 2022) was undertaken. Main eligibility criteria include older adults aged ≥60 years living at home, in an institution or in hospital. Studies carried out for a specific medical condition or targeting only micronutrient fortification were excluded. After reviewing all titles/abstracts then full-text papers, key data were extracted and synthesized narratively. The quality of included studies was assessed using Kmet et al.

Results

Of 21,493 papers extracted, 44 original studies were included (3,384 participants), with 31 reporting nutritional outcomes, 3 reporting acceptability outcomes and 10 reporting both nutritional and acceptability outcomes. The review highlighted a wide variety of DIY fortified recipes, with additional energy ranging from 23 to 850 kcal/d (M = 403; SE = 62) and/or protein ranging from 4 to 40 g/d (M = 19; SE = 2). Compared to a standard diet, DIY fortification seems to be a valuable strategy for increasing energy and protein intake in older people. However, no strong evidence was observed on the nutritional status.

Implication for future

Further acceptability studies are crucial to ensure that DIY fortified foods are palatable and thus have a significant impact on the nutritional status. In addition, it would be useful for studies to better describe DIY recipes. This information would result in a better understanding of the factors that maximize the impact of DIY fortification on nutritional outcomes. Study registration: PROSPERO no. CRD42021244689.Systematic review registration: PROSPERO: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021244689.

The feasibility of a 6-month dietary intervention aiming to increase protein intake among community-dwelling older adults with low habitual protein intake: A secondary analysis of the PROMISS randomised controlled trial

BACKGROUND

The PROMISS randomised controlled trial showed that personalised dietary advice increased protein intake and improved 400-m walk time and leg strength among community-dwelling older adults with a low habitual protein intake. This secondary analysis describes and further evaluates the methods and feasibility of the model used to carry out dietary intervention in the PROMISS randomised controlled trial.

METHODS

In total, 185 participants (≥65 years, 54% women) with a habitual low protein intake (<1.0 g/kg adjusted body weight/day) in Finland and the Netherlands received personalised dietary advice and complimentary protein-enriched food products for 6 months with two main objectives: (1) to increase protein intake to ≥1.2 g/kg adjusted body weight/day (energy-neutral) and (2) to include each day a 'high-protein meal' containing ≥ 30-35 g of protein. The feasibility of the model was evaluated by the adoption of the advice, feedback from the participants, and practical experiences by the nutritionists.

RESULTS

In all, 174 participants (93.5%) completed the intervention. At the 6-month follow-up, 41.8% reached both main objectives of the advice. The participants' general rating for the dietary advice was 8.6 (SD 1.0) (on a scale of 1-10; 10 indicating very good). Sticking to the advice was (very) easy for 79.2% of the participants. The nutritionists perceived the model feasible for the participants except for those with low food intake.

CONCLUSIONS

The methods used in this model are mainly feasible, well-received and effective in increasing protein intake among community-dwelling older adults with low habitual protein intake.

Transcriptomic Analysis of Human Skeletal Muscle in Response to Aerobic Exercise and Protein Intake

This study aimed to provide a more comprehensive molecular insight into the effects of aerobic exercise (AE), protein intake (PI), and AE combined with PI on human skeletal muscle by comparing their transcriptomic profiles. Fourteen published datasets obtained from the Gene Expression Omnibus (GEO) database were used. The hub genes were identified in response to acute AE (ACTB, IL6), training AE (UBB, COL1A1), PI (EZH2), acute AE combined with PI (DDIT3), and training AE combined with PI (MYC). Both FOS and MYC were upregulated in response to acute AE, and they were, respectively, downregulated by higher PI and a combination of AE and PI. COL1A1 was upregulated by training AE but was downregulated by higher PI. Results from the gene set enrichment analysis (p < 0.05 and FDR < 25%) showed that AE and PI delivered their impacts on human skeletal muscle in analogous pathways, including aerobic respiration, mitochondrial complexes, extracellular matrix (ECM) remodeling, metabolic process, and immune/inflammatory responses, whereas, PI may attenuate the response of immune/inflammation and ECM remodeling which would be promoted by AE, irrespective of its types. Compared to PI alone, acute AE combined with PI would further promote protein turnover and synthesis, but suppress skeletal muscle contraction and movement.

Effect of protein supplementation on plasma sodium levels in the syndrome of inappropriate antidiuresis: a monocentric, open-label, proof-of-concept study-the TREASURE study

IMPORTANCE

The syndrome of inappropriate antidiuresis (SIAD) can be treated with oral urea; however, compliance is impaired by its poor palatability.

OBJECTIVE

To investigate whether dietary proteins could increase plasma sodium levels through urea-induced osmotic diuresis.

DESIGN

An open-label, proof-of-concept trial.

SETTING

University Hospital of Basel, Switzerland, between October 2021 and February 2023.

PARTICIPANTS

Outpatients with chronic SIAD.

INTERVENTIONS OR EXPOSURES

Ninety grams of protein daily for 7 days in the form of protein powder, followed by 30 g of oral urea daily for 7 days after a wash-out period of ≥1 week.

MAIN OUTCOMES AND MEASURES

The increase in sodium levels from baseline to the end of the 7-day protein supplementation.

RESULTS

Seventeen patients were included. After 7 days of 90 g daily protein supplementation (n = 17), plasma sodium levels increased from 131 (129-133) to 133 (132-137), that is, by a median of 3 mmol L-1 (0-5) (P = .01). Plasma urea levels increased by 3 mmol L-1 (1.7-4.9) (P < .01), and urine urea to creatinine ratio increased by 21.2 mmol mmol-1 (6.2-29.1) (P < .01). After 7 days of 30 g oral urea (n = 10), plasma sodium levels increased from 132 (130-133) to 134 (131-136), that is, by a median of 2 mmol L-1 (1-3) (P = .06). Plasma urea levels increased by 5.8 mmol L-1 (2.7-9.2) (P < .01), and urine urea to creatinine ratio increased by 31.0 mmol mmol-1 (18.7-45.1) (P < .01).

CONCLUSIONS AND RELEVANCE

Our findings suggest that protein powder increases plasma sodium levels in patients with chronic SIAD through protein-induced ureagenesis and osmotic diuresis. The effects are comparable with oral urea.

Effectiveness of individual nutrition counselling for the prevention of undernutrition among elderly people living in depopulated areas: secondary analysis of a model project in Tsu city

Objectives

To examine the effectiveness of nutrition counselling (NC) in preventing undernutrition in elderly people living in depopulated areas.

Design

Participants were elderly people aged at least 65 years living in a depopulated area. Participants completed self-administered questionnaires evaluating nutritional status, frailty and body composition at the start of the study, after a non-NC period (3-month control) and after an NC period (3-month intervention). During the NC period, participants attended monthly 1-hour NC sessions over 3 months. Sessions were conducted in three areas (A, B and C), and the schedule was staggered so that the NC period in one area was conducted simultaneously with the non-NC period of the next. All sessions within an area were attended by the same registered dietitian. Outcomes were assessed three times: before the non-NC period, after the non-NC period and after the NC period. The effects of NC were assessed by comparing the results between the non-NC and NC periods of all participants, using the Cochran-Mantel-Haenszel stratified test.

Outcome measures

The primary outcome was undernutrition, as determined by the Mini Nutritional Assessment-Short Form. Secondary outcomes were Dietary Diversity Score (DVS), body weight and frailty. Body composition was also assessed.

Results

Of 106 individuals who joined the project, 61 completed the project and were analysed. The NC in this study had no effect on the primary outcome. DVS in area A was significantly higher after the NC period than after the non-NC period (p=0.012). Frailty in area C was significantly lower after the NC period than after the non-NC period (p=0.025). NC had no significant effects on the other outcomes.

Conclusions

NC improved food variety but did not improve nutritional status, frailty or body composition.

Advances in nutritional supplementation for sarcopenia management

Sarcopenia is a syndrome characterized by a decline in muscular mass, strength, and function with advancing age. The risk of falls, fragility, hospitalization, and death is considerably increased in the senior population due to sarcopenia. Although there is no conclusive evidence for drug treatment, resistance training has been unanimously recognized as a first-line treatment for managing sarcopenia, and numerous studies have also pointed to the combination of nutritional supplementation and resistance training as a more effective intervention to improve quality of life for people with sarcopenia. People with both malnutrition and sarcopenia have a higher mortality rate, so identifying people at risk of malnutrition and intervening early is extremely important to avoid sarcopenia and its associated problems. This article provides important information for dietary interventions in sarcopenia by summarizing the discoveries and developments of nutritional supplements such as protein, leucine, β-hydroxy-β-methylbutyric acid, vitamin D, vitamin C, vitamin E, omega-3 fatty acids, creatine, inorganic nitrate, probiotics, minerals, collagen peptides, and polyphenols in the management of sarcopenia.

Whey Protein Supplementation with or without Vitamin D on Sarcopenia-Related Measures: A Systematic Review and Meta-Analysis

The effects of supplementation with whey protein alone or with vitamin D on sarcopenia-related outcomes in older adults are unclear. We aimed to assess the effect of whey protein supplementation alone or with vitamin D on lean mass (LM), strength, and function in older adults with or without sarcopenia or frailty. We searched PubMed, Web of Science, and SCOPUS databases. Randomized controlled trials (RCT) that investigated the effect of whey protein supplementation with or without vitamin D on sarcopenia outcomes in healthy and sarcopenic or frail older adults were included. Standardized mean differences (SMDs) were calculated for LM, muscle strength, and physical function data. The analysis showed that whey protein supplementation had no effect on LM and muscle strength; nevertheless, a significant improvement was found in physical function (SMD = 0.561; 95% confidence interval [CIs]: 0.256, 0.865, n = 33), particularly gait speed (GS). On the contrary, whey protein supplementation significantly improved LM (SMD = 0.982; 95% CI: 0.228, 1.736; n = 11), appendicular lean mass and physical function (SMD = 1.211; 95% CI: 0.588, 1.834; n = 16), and GS in sarcopenic/frail older adults. By contrast, co-supplementation with vitamin D enhanced LM gains (SMD =0.993; 95% CI: 0.112, 1.874; n = 11), muscle strength (SMD =2.005; 95% CI: 0.975, 3.035; n = 11), and physical function (SMD = 3.038; 95% CI: 2.196, 3.879; n = 18) significantly. Muscle strength and physical function improvements after whey protein supplementation plus vitamin D were observed without resistance exercise (RE) and short study duration subgroups. Moreover, the combination of whey protein and vitamin D with RE did not enhance the effect of RE. Whey protein supplementation improved LM and function in sarcopenic/frail older adults but had no positive effect in healthy older persons. By contrast, our meta-analysis showed that co-supplementation with whey protein and vitamin D is effective, particularly in healthy older adults, which is likely owing, we propose, to the correction of vitamin D insufficiency or deficiency. The trial was registered at https://inplasy.com as INPLASY202240167.

Muscle Mass Changes After Daily Consumption of Protein Mix Supplemented With Vitamin D in Adults Over 50 Years of Age: Subgroup Analysis According to the Serum 25(OH)D Levels of a Randomized Controlled Trial

Early prevention of sarcopenia can be an important strategy for muscle maintenance, but most studies target subjects at slightly pre-sarcopenic state. Our previous paper describes the effect of protein supplements rich in leucine and vitamin D on muscle condition, and in this paper, we performed a sub-analysis to evaluate who benefitted the most in terms of improvement in muscle health. A 12-week randomized clinical trial of 120 healthy adults (aged 50 to 80) assigned to an intervention group (n = 60) or control group (n = 60) were analyzed. Subjects in the intervention group received, twice per day, a protein supplement containing (per serving) 800 IU of vitamin D, 20 g of protein (3 g of total leucine), 300 mg of calcium, 1.1 g of fat, and 2.5 g of carbohydrate. The subjects were classified into 'insufficient' and 'sufficient' groups at 25-hydroxyvitamin D (25[OH]D) value of 30 ng/mL. The skeletal muscle mass index normalized to the square of the skeletal muscle mass (SMM) height (kg/m2) increased significantly in the 'insufficient group' difference value of change between weeks 0 and 12 (Δ1.07 ± 2.20; p = 0.037). The SMM normalized by body weight (kg/kg, %) was higher, but not significantly, in the insufficient group (Δ0.38 ± 0.69; p = 0.050). For people with insufficient (serum 25[OH]D), supplemental intake of protein and vitamin D, calcium, and leucine and adequate energy intake increases muscle mass in middle-aged and older adults and would be likely to exert a beneficial effect on muscle health.

Trial Registration

Clinical Research Information Service Identifier: KCT0005111.

Relationships between sarcopenia, nutrient intake, and gut microbiota in Chinese community-dwelling older women

BACKGROUND

The relationship among gut microbiota, sarcopenia components, and influencing factors in female sarcopenic patients has been poorly investigated.

METHODS

Female participants completed questionnaires of physical activity and dietary frequency and were assessed for the presence of sarcopenia by the Asian Working Group of Sarcopenia 2019 (AWGS 2019) criteria. Fecal samples were collected from 17 sarcopenia and 30 non-sarcopenia subjects for 16S sequencing and short chain fatty acid (SCFA) detection.

RESULTS

The prevalence of sarcopenia was 19.20% among 276 participants. The dietary protein, fat, dietary fiber, vitamin B1, niacin, vitamin E, phosphorus, magnesium, iron, zinc, and cooper intake of sarcopenia were all remarkably low. In addition, the richness of gut microbiota (Chao1 and ACE indexes) was considerably reduced in sarcopenic patients, and the sarcopenic gut microbiota and its metabolite were decreased in Firmicutes/Bacteroidetes, Agathobacter, Dorea and Butyrate and were enriched in Shigella and Bacteroides. Correlation analysis showed that Agathobacter and Acetate were positively correlated with grip strength and gait speed, respectively, and Bifidobacterium was negatively correlated with grip strength and appendicular skeletal muscle index (ASMI). Moreover, the protein intake was positively related to Bifidobacterium.

CONCLUSIONS

This cross-sectional study revealed the alterations of gut microbiota composition, SCFA, and nutrient intake in women with sarcopenia and their relation to sarcopenic components. These results provide insights into further studies on the role of nutrition and gut microbiota in sarcopenia and its use as a therapeutic approach.

Association between masseter muscle volume, nutritional status, and cognitive status in older people

OBJECTIVES

Clinical evidence has suggested that oral function is associated with cognitive, physical, and nutritional status of older people. A smaller volume of masseter, a crucial muscle for mastication, was associated with frailty. It has remained unknown if smaller masseter is associated with cognitive impairment. The current study investigated the association between masseter muscle volume, nutritional status, and cognitive status in older people.

MATERIALS AND METHODS

We recruited 19 patients with mild cognitive impairment (MCI), 15 patients with Alzheimer's disease (AD), and 28 sex and age-matched non-cognitive impairment (non-CI) older subjects. The number of missing teeth (NMT), masticatory performance (MP), maximal hand-grip force (MGF), and calf circumference (CC) were assessed. The masseter volume index (MVI) was calculated based on the masseter volume measured using magnetic resonance imaging.

RESULTS

The MVI was significantly lower in the AD group, compared to the MCI as well as the non-CI group. Multiple regression analyses revealed that the MVI was significantly associated with nutritional status (as indexed by CC) in the analysis of combination of NMT, MP, and the MVI. Moreover, the MVI was a significant predictor of CC only in patients with cognitive impairment (i.e., MCI+AD) but not in the non-CI group.

CONCLUSIONS

Our findings suggested that in addition to the NMT and MP, masseter volume is a critical oral factor associated with cognitive impairment.

CLINICAL RELEVANCE

Reduction of MVI should be carefully monitored for patients with dementia and frailty, to whom a lower MVI may indicate worse nutrient intake.

The Effects of Protein and Supplements on Sarcopenia in Human Clinical Studies: How Older Adults Should Consume Protein and Supplements

Sarcopenia is a condition in which muscle mass, strength, and performance decrease with age. It is associated with chronic diseases such as diabetes, cardiovascular disease, and hypertension, and contributes to an increase in mortality. Because managing sarcopenia is critical for maintaining good health and quality of life for the elderly, the condition has sparked concern among many researchers. To counteract sarcopenia, intake of protein is an important factor, while a lack of either protein or vitamin D is a major cause of sarcopenia. In addition, essential amino acids, leucine, β-hydroxy β-methylbutyrate (HMB), creatine, and citrulline are used as supplements for muscle health and are suggested as alternatives for controlling sarcopenia. There are many studies on such proteins and supplements, but it is necessary to actually organize the types, amounts, and methods by which proteins and supplements should be consumed to inhibit sarcopenia. In this study, the efficacy of proteins and supplements for controlling sarcopenia according to human clinical studies is summarized to provide suggestions about how the elderly may consume proteins, amino acids, and other supplements.

Association of frailty with the incidence risk of cardiovascular disease and type 2 diabetes mellitus in long-term cancer survivors: a prospective cohort study

BACKGROUND

Comorbidities among cancer survivors remain a serious healthcare burden and require appropriate management. Using two widely used frailty indicators, this study aimed to evaluate whether frailty was associated with the incidence risk of cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM) among long-term cancer survivors.

METHODS

We included 13,388 long-term cancer survivors (diagnosed with cancer over 5 years before enrolment) free of CVD and 6101 long-term cancer survivors free of T2DM, at the time of recruitment (aged 40-69 years), from the UK Biobank. Frailty was assessed by the frailty phenotype (FP_Frailty, range: 0-5) and the frailty index (FI_Frailty, range: 0-1) at baseline. The incident CVD and T2DM were ascertained through linked hospital data and primary care data, respectively. The associations were examined using Cox proportional hazards regression models.

RESULTS

Compared with non-frail participants, those with pre-frailty (FP_Frailty [met 1-2 of the components]: hazard ratio [HR]=1.18, 95% confidence interval [CI]: 1.05, 1.32; FI_Frailty [0.10< FI ≤0.21]: HR=1.51, 95% CI: 1.32, 1.74) and frailty (FP_Frailty [met ≥3 of the components]: HR=2.12, 95% CI: 1.73, 2.60; FI_Frailty [FI >0.21]: HR=2.19, 95% CI: 1.85, 2.59) had a significantly higher risk of CVD in the multivariable-adjusted model. A similar association of FI_Frailty with the risk of incident T2DM was observed. We failed to find such an association for FP_Frailty. Notably, the very early stage of frailty (1 for FP_Frailty and 0.1-0.2 for FI_Frailty) was also positively associated with the risk of CVD and T2DM (FI_Frailty only). A series of sensitivity analyses confirmed the robustness of the findings.

CONCLUSIONS

Frailty, even in the very early stage, was positively associated with the incidence risk of CVD and T2DM among long-term cancer survivors, although discrepancies existed between frailty indicators. While the validation of these findings is required, they suggest that routine monitoring, prevention, and interventive programs of frailty among cancer survivors may help to prevent late comorbidities and, eventually, improve their quality of life. Especially, interventions are recommended to target those at an early stage of frailty when healthcare resources are limited.

Frailty knowledge level and its influencing factors among older adults in China

Raising older adults' frailty knowledge level and encouraging them to actively engage in the prevention and treatment of frailty is essential to promote healthy aging. This cross-sectional study investigated frailty knowledge level and its influencing factors in community-dwelling older adults in China. A total of 734 older adults were included in the analysis. About half of them misjudged their frailty state (42.50%), and 17.17% obtained frailty knowledge in the community. Those who were female, lived in rural areas, lived alone, had not attended school, had a monthly income <3,000RMB, were at risk for malnutrition, were depressed, and were socially isolated were more likely to have lower frailty knowledge level. Those with advanced age and pre-frailty or frailty stage were more knowledgeable about frailty. The group with the highest proportion of low frailty knowledge level was those who had never attended school or completed primary school and had loose friend ties (98.7%). It is crucial to develop tailored intervention to raise frailty knowledge level in older adults in China.

Is It Time to Reconsider the U.S. Recommendations for Dietary Protein and Amino Acid Intake?

Since the U.S. Institute of Medicine's recommendations on protein and amino acid intake in 2005, new information supports the need to re-evaluate these recommendations. New lines of evidence include: (1) re-analysis/re-interpretation of nitrogen balance data; (2) results from indicator amino acid oxidation studies; (3) studies of positive functional outcomes associated with protein intakes higher than recommended; (4) dietary guidance and protein recommendations from some professional nutrition societies; and (5) recognition that the synthesis of certain dispensable amino acids may be insufficient to meet physiological requirements more often than previously understood. The empirical estimates, theoretical calculations and clinical functional outcomes converge on a similar theme, that recommendations for intake of protein and some amino acids may be too low in several populations, including for older adults (≥65 years), pregnant and lactating women, and healthy children older than 3 years. Additional influential factors that should be considered are protein quality that meets operational sufficiency (adequate intake to support healthy functional outcomes), interactions between protein and energy intake, and functional roles of amino acids which could impact the pool of available amino acids for use in protein synthesis. Going forward, the definition of "adequacy" as it pertains to protein and amino acid intake recommendations must take into consideration these critical factors.

Secondhand smoke is positively associated with pre-frailty and frailty in non-smoking older adults

Introduction

Either exposure to secondhand smoke (SHS) or frailty has been linked to adverse health outcomes in nonsmoking adults. However, their relationship is rarely studied. The purpose of this study is to examine the association between serum cotinine level and frailty status among non-smoking older adults.

Method

The study population consisted of 2,703 older adults aged ≥60 from the National Health and Nutrition Examination Survey 2011-2014. Non-smokers were included based on (1) a serum cotinine level ≤ 10 ng/mL and 2) a response of "no" to the question, "Do you currently smoke?" Frailty status was measured based on the Fried Phenotype and had three groups- robust, pre-frailty, and frailty. Multinomial logistic regression models were constructed to examine the association between serum cotinine level quartile and frailty status, controlling for age, sex, race/ethnicity, education, depressive symptoms, alcohol use, and systolic blood pressure.

Results

About half of the participants (median age 70.0 years, range 64-78) were female (53.6%), non-Hispanic White (48.3%), and completed some college and above (50.1%). Multinomial logistic regression with a reference group being those in the 1st quantile (the lowest) of serum cotinine level showed that participants in the 4th quartile (the highest) of serum cotinine level had increased odds of pre-frailty vs. robust (OR 1.522, 95% confidence interval [CI] 1.060, 2.185, P = 0.023) as well as increased odds of frailty vs. robust (OR 2.349, 95% CI 1.081, 5.107, P = 0.031).

Conclusions

Higher serum cotinine level is associated with increased risk of pre-frailty and frailty versus robust in non-smoking older adults. Prevention and reduction of SHS in older adults may help protect them from developing pre-frailty or frailty.

Demystifying Malnutrition to Improve Nutrition Screening and Assessment in Oncology

OBJECTIVE

Patients with cancer and malnutrition are more likely to experience poor treatment tolerance, prolonged length of hospital stay, and decreased quality of life. Early and sustained nutrition risk screening is the first step to tackling this patient and health care burden. Yet, malnutrition remains largely overlooked and undertreated. Malnutrition mismanagement could be indicative of a systemic misunderstanding. With this narrative review, we aimed to (1) define malnutrition, (2) address common malnutrition misconceptions, and (3) summarize nutrition recommendations for patients with cancer.

DATA SOURCES

PubMed and international clinical practice guidelines were used.

CONCLUSION

Malnutrition represents an unbalanced nutritional state that alters body composition and diminishes function. Malnutrition is not always physically obvious, and albumin is not a reliable marker of nutritional status; therefore, systematically screening all patients with a validated nutrition risk screening tool at time of cancer diagnosis, and periodically throughout treatment, is necessary to provide optimal, equitable care. Nutrition risk screening takes less than 1 minute to complete and can be completed by any health care professional. Patients that screen positive for nutrition risk should be referred to a registered nutritionist or dietitian for comprehensive nutritional assessment, diagnosis, and treatment.

IMPLICATIONS FOR NURSING PRACTICE

All health care professionals can and should be responsible for preventing and treating malnutrition. Registered nurses can actively participate in improving patient outcomes by screening patients for nutrition risk, weighing patients at every visit, referring patients to dietitians for nutrition treatment, and providing supportive medical management of nutrition impact symptoms such as nausea.

Towards developing a Core Outcome Set for malnutrition intervention studies in older adults: a scoping review to identify frequently used research outcomes

PURPOSE

To conduct a scoping review to provide a systematic overview of outcomes used in nutritional intervention studies focused on the treatment of protein-energy malnutrition in older adults.

METHODS

A systematic search of four electronic databases (Medline, EMBASE, CINAHL and Cochrane Central Register of Controlled Trials (CENTRAL) was performed to retrieve randomized controlled trials (RCTs), published until March 9, 2020, that evaluated the effect of nutritional interventions to treat protein-energy malnutrition in older adults and those at risk for malnutrition. Two authors screened titles, abstracts and full texts independently. One author extracted data that were cross-checked by another author.

RESULTS

Sixty-three articles reporting 60 RCTs were identified. Most frequently used outcomes included body weight/body mass index (75.0% of RCTs), dietary intake (61.7%), functional limitations (48.3%), handgrip strength (46.7%), and body circumference (40.0%). The frequencies differed by setting (community, hospital and long-term care). For some outcomes there was a preferred assessment method (e.g., Barthel index for functional limitations), while for other outcomes (e.g., functional performance) a much greater variation was observed.

CONCLUSION

A large variation in outcomes, not only across but also within settings, was identified in nutritional intervention studies in malnourished older adults and those at risk. Furthermore, for many outcomes there was a large variation in the used assessment method. These results highlight the need for developing a Core Outcome Set for malnutrition intervention studies in older adults to facilitate future meta-analyses that may enhance our understanding on the effectiveness of treatment.

Tailoring prehabilitation to address the multifactorial nature of functional capacity for surgery

Mounting evidence suggests that recovery begins before the surgical incision. The pre-surgery phase of recovery - the preparation for optimal surgical recovery - can be reinforced with prehabilitation. Prehabilitation is the approach of enhancing the functional capacity of the individual to enable them to withstand a stressful event. With this narrative review, we apply the Wilson & Cleary conceptual model of patient outcomes to specify the complex and integrative relationship of health factors that limit functional capacity before surgery. To have the greatest impact on patient outcomes, prehabilitation programs require individualized and coordinated care from medical, nutritional, psychosocial, and exercise services. This article is protected by copyright. All rights reserved.

Changes in 24-h energy expenditure, substrate oxidation, and body composition following resistance exercise and a high protein diet via whey protein supplementation in healthy older men

PURPOSE

To investigate changes in 24-h energy expenditure (EE), substrate oxidation, and body composition following resistance exercise (RE) and a high protein diet via whey protein supplementation (alone and combined) in healthy older men.

METHODS

In a pooled groups analysis, 33 healthy older men [(mean ± SE) age: 67 ± 1 years; BMI: 25.4 ± 0.4 kg/m2] were randomized to either RE (2×/week; n = 17) or non-exercise (n = 16) and either a high protein diet via whey protein supplementation (PRO, 2 × 25 g whey protein isolate/d; n = 17) or control (CON, 2 × 23.75 g maltodextrin/d; n = 16). An exploratory sub-analysis was also conducted between RE+CON (n = 8) and RE+PRO (n = 9). At baseline and 12 weeks, participants resided in respiration chambers for measurement of 24-h EE and substrate oxidation and wore an accelerometer for 7 days for estimation of free-living EE.

RESULTS

Resistance exercise resulted in greater increases in fat-free mass (1.0 ± 0.3 kg), resting metabolic rate [(RMR) 36 ± 14 kcal/d], sedentary EE (60 ± 33 kcal/d), and sleeping metabolic rate [(SMR) 45 ± 7 kcal/d] compared to non-exercise (p < 0.05); however, RE decreased activity energy expenditure in free-living (-90 ± 25 kcal/d; p = 0.049) and non-exercise activity inside the respiration chamber (-1.9 ± 1.1%; p = 0.049). PRO decreased fat mass [(FM) -0.5 ± 0.3 kg], increased overnight protein oxidation (30 ± 6 g/d), and decreased 24-h protein balance (-20 ± 4 g/d) greater than CON (p < 0.05). RE+PRO decreased FM (-1.0 ± 0.5 kg) greater than RE+CON (p = 0.04).

CONCLUSION

Resistance exercise significantly increased RMR, SMR, and sedentary EE in healthy older men, but not total EE. PRO alone and combined with RE decreased FM and aided body weight maintenance. This study was registered at clinicaltrials.gov as NCT03299972.

Muscle-Related Effect of Whey Protein and Vitamin D3 Supplementation Provided before or after Bedtime in Males Undergoing Resistance Training

There is increasing evidence that dietary protein intake with leucine and vitamin D is an important factor in muscle protein synthesis. This study investigated the combined effects of consuming whey protein and vitamin D₃ in the evening before bedtime or in the morning after sleeping on muscle mass and strength. Healthy, untrained males (N = 42; Age = 18-24 year) were randomly assigned into three groups: before bedtime, after sleeping, and control. Subjects underwent a 6-week resistance training program in combination with supplements that provided 25 g whey protein and 4000 IU vitamin D₃ for the before bedtime and after sleeping groups and a 5 g maltodextrin placebo for the control group. A significant increase in serum vitamin D was observed in both before bedtime and after sleeping groups. All groups experienced a significant gain in leg press. However, the control group did not experience significant improvements in muscle mass and associated blood hormones that were experienced by the before bedtime and after sleeping groups. No significant differences in assessed values were observed between the before bedtime and after sleeping groups. These findings suggest that the combination of whey protein and vitamin D supplements provided either before or after sleep resulted in beneficial increases in muscle mass in young males undergoing resistance training that exceeded the changes observed without these supplements.

A review of recent evidence of dietary protein intake and health

The Korea National Health and Nutrition Examination Survey of 2013 to 2017 reported that the average protein consumption of the Korean population is above the current recommended nutrient intake of protein proposed by the Dietary Reference Intakes for Koreans. Some health professionals and the media often advise consuming diets high in protein for promoting metabolic regulation, weight control, and muscle synthesis. However, due to lack of scientific evidence, the validity and safety of high protein consumption are yet to be fully ascertained. The present review assesses recent evidence published in 2014-2020 from human studies, focusing on adequate protein intake and protein sources for the prevention of chronic diseases, particularly metabolic disorders and sarcopenia.

High Intensity Interval Training: A Potential Method for Treating Sarcopenia

Sarcopenia, an age-related disease characterized by loss of muscle strength and muscle mass, has attracted the attention of medical experts due to its severe morbidity, low living quality, high expenditure of health care, and mortality. Traditionally, persistent aerobic exercise (PAE) is considered as a valid way to attenuate muscular atrophy. However, nowadays, high intensity interval training (HIIT) has emerged as a more effective and time-efficient method to replace traditional exercise modes. HIIT displays comprehensive effects on exercise capacity and skeletal muscle metabolism, and it provides a time-out for the recovery of cardiopulmonary and muscular functions without causing severe adverse effects. Studies demonstrated that compared with PAE, HIIT showed similar or even higher effects in improving muscle strength, enhancing physical performances and increasing muscle mass of elder people. Therefore, HIIT might become a promising way to cope with the age-related loss of muscle mass and muscle function. However, it is worth mentioning that no study of HIIT was conducted directly on sarcopenia patients, which is attributed to the suspicious of safety and validity. In this review, we will assess the effects of different training parameters on muscle and sarcopenia, summarize previous papers which compared the effects of HIIT and PAE in improving muscle quality and function, and evaluate the potential of HIIT to replace the status of PAE in treating old people with muscle atrophy and low modality; and point out drawbacks of temporary experiments. Our aim is to discuss the feasibility of HIIT to treat sarcopenia and provide a reference for clinical scientists who want to utilize HIIT as a new way to cope with sarcopenia.

Physiological Systems in Promoting Frailty

Frailty is a complex syndrome affecting a growing sector of the global population as medical developments have advanced human mortality rates across the world. Our current understanding of frailty is derived from studies conducted in the laboratory as well as the clinic, which have generated largely phenotypic information. Far fewer studies have uncovered biological underpinnings driving the onset and progression of frailty, but the stage is set to advance the field with preclinical and clinical assessment tools, multiomics approaches together with physiological and biochemical methodologies. In this article, we provide comprehensive coverage of topics regarding frailty assessment, preclinical models, interventions, and challenges as well as clinical frameworks and prevalence. We also identify central biological mechanisms that may be at play including mitochondrial dysfunction, epigenetic alterations, and oxidative stress that in turn, affect metabolism, stress responses, and endocrine and neuromuscular systems. We review the role of metabolic syndrome, insulin resistance and visceral obesity, focusing on glucose homeostasis, adenosine monophosphate-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR), and nicotinamide adenine dinucleotide (NAD+ ) as critical players influencing the age-related loss of health. We further focus on how immunometabolic dysfunction associates with oxidative stress in promoting sarcopenia, a key contributor to slowness, weakness, and fatigue. We explore the biological mechanisms involved in stem cell exhaustion that affect regeneration and may contribute to the frailty-associated decline in resilience and adaptation to stress. Together, an overview of the interplay of aging biology with genetic, lifestyle, and environmental factors that contribute to frailty, as well as potential therapeutic targets to lower risk and slow the progression of ongoing disease is covered. © 2022 American Physiological Society. Compr Physiol 12:1-46, 2022.