Protein Intake and Distribution in Relation to Physical Functioning and Quality of Life in Community-Dwelling Elderly People: Acknowledging the Role of Physical Activity

Novel dietary strategies to manage sarcopenia

PURPOSE OF REVIEW

Sarcopenia is a wasting disease, mostly age-related in which muscle strength and mass decline, such as physical performance. With aging, both lower dietary protein intake and anabolic resistance lead to sarcopenia. Moreover, aging and sarcopenia display low-grade inflammation, which also worsen muscle condition. In this review, we focused on these two main targets to study dietary strategies.

RECENT FINDINGS

The better understanding in mechanisms involved in sarcopenia helps building combined dietary approaches including physical activity that would slow the disease progression. New approaches include better understanding in the choice of quality proteins, their amount and schedule and the association with antioxidative nutrients.

SUMMARY

First, anabolic resistance can be countered by increasing significantly protein intake. If increasing amount remains insufficient, the evenly delivery protein schedule provides interesting results on muscle strength. Quality of protein is also to consider for decreasing risk for sarcopenia, because varying sources of proteins appears relevant with increasing plant-based proteins ratio. Although new techniques have been developed, as plant-based proteins display a lower availability, we need to ensure an adapted overall amount of proteins. Finally, specific enrichment with leucine from whey protein remains the dietary combined approach most studied and studies on citrulline provide interesting results. As cofactor at the edge between anabolic and antioxidative properties, vitamin D supplementation is to recommend. Antioxidative dietary strategies include both fibers, vitamins, micronutrients and polyphenols from various sources for positive effects on physical performance. The ω 3 -polyunsaturated fatty acids also display positive modifications on body composition. Gut microbiota modifiers, such as prebiotics, are promising pathways to improve muscle mass and function and body composition in sarcopenic patients. Nutritional interventions could be enhanced by combination with physical activity on sarcopenia. In healthy older adults, promoting change in lifestyle to get near a Mediterranean diet could be one of the best options. In sarcopenia adults in which lifestyle changes appears unprobable, specific enrichement potentialized with physical activity will help in the struggle against sarcopenia. Longitudinal data are lacking, which makes it hard to draw strong conclusions. However, the effects of a physical activity combined with a set of nutrition interventions on sarcopenia seems promising.

Association between adherence to the Nordic diet and frailty in older adults: A systematic review of observational studies

BACKGROUND

The Nordic or Baltic Sea diet is a healthy plant-based dietary pattern composed of foods originating from Nordic countries, closely related to the Mediterranean diet. Adherence to the Mediterranean diet has been found to be associated with a reduced risk of frailty. Although adherence to the Nordic diet has been associated with health benefits, little is known about its association with frailty.

OBJECTIVES

To investigate the evidence from observational studies regarding the association between the Nordic/Baltic Sea diet and frailty among older adults.

DESIGN

Systematic review.

METHODS

Three databases (Medline/Ovid, Embase/Ovid, and Scopus) were systematically searched in February 2023 for observational studies examining the association between adherence to the Nordic diet and frailty among adults ≥60 years. The two authors independently assessed the full text of the papers for eligibility of studies and risk of bias.

RESULTS

Three studies (the results of which were reported across 6 papers) met the inclusion criteria, among which one study (2 papers) included only women. Greater adherence to the Nordic diet was associated with a reduced risk of frailty measured by modified Fried criteria in women (one study). Moreover, greater adherence to the Nordic diet was associated with improved muscle (handgrip/leg) strength (one study) and physical performance (two studies), but these differences were seen only in women, with no significant results in men in two studies. Greater adherence to the Nordic diet was also associated with a lower risk of mobility limitations and improved ability to carry out self-care tasks (one study) and a borderline non-significant difference in Activities of Daily Living (one study). A meta-analysis was not performed due to heterogenous outcomes. Although all studies were of good quality, the results should be carefully interpreted due to methodological limitations.

CONCLUSIONS

Adherence to the Nordic diet could be promising in reducing frailty risk, but more robust studies with equal gender representation and frailty-specific outcomes are needed.

Protein - a scoping review for Nordic Nutrition Recommendations 2023

Proteins are needed for providing essential amino acids, nitrogen, and fuel for the body's needs in all age groups. Proteins are especially required during active growth in pregnancy, lactation, childhood, and tissue growth in general. An adequate protein intake is needed in old adults to avoid premature muscle loss. According to the current dietary surveys, protein intake in the Nordic and Baltic countries varies from 15 to 19% of the total energy intake in adults. Comprehensive data regarding children and older adults are lacking. No good measure for protein status exists, and the estimation of physiological requirements is based on N-balance studies having some weaknesses. Protein quality is assessed by considering the protein digestibility of individual indispensable amino acids and their utilization (bioavailability), which is affected by food antinutrients and processing. The evidence regarding the association of protein intake per se with health outcomes is limited or suggestive. It is difficult to separate from the effect of other nutrients or ingredients in protein-rich foods. Proteins are widespread in foods, deriving from both animal and plant sources. Animal-sourced protein production puts more strain on the environment than plant-sourced proteins and contributes significantly to greenhouse gas emissions, thereby enhancing climate change. In Nordic and Baltic countries, consumption of animal-sourced proteins is relatively high. A shift toward more plant-based protein diets would be advisable for promoting a healthy and sustainable diet.

Associations of protein intake, sources and distribution on muscle strength in community-dwelling older adults living in Auckland, New Zealand

Protein intake, sources and distribution impact on muscle protein synthesis and muscle mass in older adults. However, it is less clear whether dietary protein influences muscle strength. Data were obtained from the Researching Eating Activity and Cognitive Health (REACH) study, a cross-sectional study aimed at investigating dietary patterns, cognitive function and metabolic syndrome in older adults aged 65-74 years. Dietary intake was assessed using a 4-d food record and muscle strength using a handgrip strength dynamometer. After adjusting for confounders, in female older adults (n 212), total protein intake (β = 0⋅22, P < 0⋅01); protein from dairy and eggs (β = 0⋅21, P = 0⋅03) and plant food sources (β = 0⋅60, P < 0⋅01); and frequently consuming at least 0⋅4 g/kg BW per meal (β = 0⋅08, P < 0⋅01) were associated with higher BMI-adjusted muscle strength. However, protein from meat and fish intake and the coefficient of variance of protein intake were not related to BMI-muscle strength in female older adults. No statistically significant associations were observed in male participants (n = 113). There may be sex differences when investigating associations between protein intake and muscle strength in older adults. Further research is needed to investigate these sex differences.

Integrated care for older multimorbid heart failure patients: protocol for the ESCAPE randomized trial and cohort study

ESCAPE

Evaluation of a patient-centred biopsychosocial blended collaborative care pathway for the treatment of multimorbid elderly patients.

THERAPEUTIC AREA

Healthcare interventions for the management of older patients with multiple morbidities.

AIMS

Multi-morbidity treatment is an increasing challenge for healthcare systems in ageing societies. This comprehensive cohort study with embedded randomized controlled trial tests an integrated biopsychosocial care model for multimorbid elderly patients.

HYPOTHESIS

A holistic, patient-centred pro-active 9-month intervention based on the blended collaborative care (BCC) approach and enhanced by information and communication technologies can improve health-related quality of life (HRQoL) and disease outcomes as compared with usual care at 9 months.

METHODS

Across six European countries, ESCAPE is recruiting patients with heart failure, mental distress/disorder plus ≥2 medical co-morbidities into an observational cohort study. Within the cohort study, 300 patients will be included in a randomized controlled assessor-blinded two-arm parallel group interventional clinical trial (RCT). In the intervention, trained care managers (CMs) regularly support patients and informal carers in managing their multiple health problems. Supervised by a clinical specialist team, CMs remotely support patients in implementing the treatment plan-customized to the patients' individual needs and preferences-into their daily lives and liaise with patients' healthcare providers. An eHealth platform with an integrated patient registry guides the intervention and helps to empower patients and informal carers. HRQoL measured with the EQ-5D-5L as primary endpoint, and secondary outcomes, that is, medical and patient-reported outcomes, healthcare costs, cost-effectiveness, and informal carer burden, will be assessed at 9 and ≥18 months.

CONCLUSIONS

If proven effective, the ESCAPE BCC intervention can be implemented in routine care for older patients with multiple morbidities across the participating countries and beyond.

Dietary Protein Intake and Physical Function in Māori and Non-Māori Adults of Advanced Age in New Zealand: LiLACS NZ

The population of older adults is growing exponentially. Research shows that current protein intake recommendations are unlikely to meet the ageing requirements and may be linked to reduced physical function. Ensuring optimal function levels is crucial for independence and quality of life in older age. This study aims to quantify the protein intake in those over 90 years of age and determine the association between historical protein intake (2011) and subsequent physical function at ten years follow-up (2021). Eighty-one participants (23 Māori and 54 non-Māori) undertook dietary assessment 24 h multiple-pass recall (MPR) and a standardised health and social questionnaire with physical assessment in 2011 and 2021. Intake24, a virtual 24 h MPR, was utilised to analyse dietary intake. Functional status was measured using the Nottingham Extended Activities of Daily Living Scale (NEADL), and physical performance was the Short Physical Performance Battery (SPPB). Māori men and women consumed less protein (g/day) in 2021 than in 2011 (P = 0.043 in men), but weight-adjusted protein intake in Māori participants over the ten years was not significantly reduced. Both non-Māori men and women consumed significantly less protein (g/day) between 2011 and 2021 (p = 0.006 and p = 0.001, respectively), which was also significant when protein intake was adjusted for weight in non-Māori women (p = 0.01). Weight-adjusted protein intake in 2011 was independently associated with functional status (NEADL score) in 2021 (p =< 0.001). There was no association between past protein intake and SPPB score (p = 0.993). Animal protein was replaced with plant-based protein over time. In conclusion, a reduction in protein intake was seen in all participants. The independent association between past protein intake and future functional status supports recommendations to keep protein intake high in advanced age.

Assessing the Effects of Dietary Protein Supplementation on Sarcopenia in Community-Dwelling Older Adults

Sarcopenia, an age-associated skeletal muscle disorder characterized by muscle loss, is associated with disability in elderly populations. This literature review summarizes the impact of protein intake and supplementation on the indicators of severe sarcopenia-muscle mass, muscle strength, and physical function in community-dwelling older adults. We performed a literature search on PubMed, EMBASE, and MedLine, and included studies that evaluated the effects of protein intake with or without exercise intervention and on sarcopenia in community-dwelling older adults. Information regarding study participants, protein intervention, and sarcopenia-related outcomes were collected. Protein supplementation with or without exercise positively improves muscle mass, and aspects of muscle strength and physical function in sarcopenic and pre-frail older adults, while it elicited inconclusive effects in healthy populations. Greater dietary animal-based and soy-based protein diets can improve muscle mass in older adults. In conclusion, protein supplementation can improve muscle mass and reduce the risk of sarcopenia in sarcopenia and pre-frail older adults, while future studies should continue to investigate the effects of protein supplementation on indicators of sarcopenia in healthy older adults.

Lower-Limb Muscle Power Is Negatively Associated with Protein Intake in Older Adults: A Cross-Sectional Study

The present study examined the association between lower-limb muscle power and protein-related parameters in older adults. This study followed a cross-sectional design. Participants were community-dwelling older adults. Candidates were considered eligible if they were 60 years or older, lived independently, and possessed sufficient physical and cognitive abilities to perform all the measurements required by the protocol. The 5 times sit-to-stand (5STS) test was performed as fast as possible according to a standard protocol. Absolute, relative, and allometric muscle power measures were estimated using 5STS-based equations. Diet was assessed by 24-h dietary recall and diet composition was estimated using a nutritional software. One-hundred and ninety-seven older adults participated to the present study. After adjustment for covariates, absolute and allometric muscle power were negatively associated with body weight-adjusted protein intake. Our findings indicate that absolute and allometric muscle power estimated through a simple equation are negatively associated with body weight-adjusted protein intake in community-dwelling older adults.

Protein intake and physical function in older adults: A systematic review and meta-analysis

BACKGROUND

The present study explored cross-sectional and longitudinal associations between protein intake and physical function in older adults.

METHODS

We conducted a systematic review and meta-analysis of cross-sectional and longitudinal studies that investigated the association between protein intake and measures of physical function in older adults. Cross-sectional, case-control, and longitudinal cohort studies that investigated the association between protein intake and physical function as a primary or secondary outcome in people aged 60 + years were included. Studies published in languages other than English, Italian, Portuguese, or Spanish were excluded. Studies were retrieved from MEDLINE, SCOPUS, EMBASE, CINAHL, AgeLine, and Food Science Source databases through January 31, 2022. A pooled effect size was calculated based on standard mean differences (SMD), MD, log odds ratio (OR) and Z-score..

RESULTS

Twenty-two cross-sectional studies examined a total of 11,332 community-dwellers, hospitalized older adults, and elite senior athletes with a mean age of approximately 75 years. The pooled analysis indicated that a protein intake higher than the recommended dietary allowance (RDA) was significantly associated with higher Short Physical Performance Battery (SPPB) scores (SMD: 0.63, 95% CI: 0.27, 0.99, P-value: 0.0006), faster walking speed, greater lower-limb (SMD: 0.22, 95% CI: 0.04, 0.40, P-value: 0.02) and isometric handgrip strength (Z-score: 0.087, 95% CI: 0.046-0.128, P-value: 0.0001), and better balance (SMD: 0.33, 95% CI: 0.05, 0.62, P-value: 0.02). Nine longitudinal studies investigated 12,424 community-dwelling and native older adults with a mean age of approximately 85 years. A protein intake higher than the current RDA was not associated with lower decline in either isometric handgrip strength (logOR: 0.99, 95% CI: 0.97-1.02, P-value= 0.67) or walking speed (logOR: 0.92, 95% CI: 0.77-1.10, P-value= 0.35).

CONCLUSIONS

A protein intake higher than the RDA is cross-sectionally associated with better physical performance and greater muscle strength in older adults. However, a high consumption of proteins does not seem to prevent physical function decline over time.

Protein Intake and Frailty in Older Adults: A Systematic Review and Meta-Analysis of Observational Studies

BACKGROUND

The present systematic review and meta-analysis investigated the cross-sectional and longitudinal associations between protein intake and frailty in older adults.

METHODS

We conducted a systematic review and meta-analysis of cross-sectional and longitudinal studies that investigated the association between protein intake and frailty in older adults. Cross-sectional, case-control, and longitudinal cohort studies that investigated the association between protein intake and frailty as a primary or secondary outcome in people aged 60+ years were included. Studies published in languages other than English, Italian, Portuguese, or Spanish were excluded. Studies were retrieved on 31 January 2022.

RESULTS

Twelve cross-sectional and five longitudinal studies that investigated 46,469 community-dwelling older adults were included. The meta-analysis indicated that absolute, bodyweight-adjusted, and percentage of protein relative to total energy consumption were not cross-sectionally associated with frailty. However, frail older adults consumed significantly less animal-derived protein than robust people. Finally, high protein consumption was associated with a significantly lower risk of frailty.

CONCLUSIONS

Our pooled analysis indicates that protein intake, whether absolute, adjusted, or relative to total energy intake, is not significantly associated with frailty in older adults. However, we observed that frail older adults consumed significantly less animal protein than their robust counterparts.

Evenness of Dietary Protein Intake Is Positively Associated with Lean Mass and Strength in Healthy Women

Background:

Evenness of protein intake is associated with increased lean mass, but its relationship with muscle strength and performance is uncertain.

Objectives:

We determined the association of evenness of protein intake with lean mass, muscle strength and endurance, and functional ability.

Design:

This was a cross-sectional study.

Setting:

Data were collected at a research university in the upper midwestern United States.

Participants:

One hundred ninety-two healthy women, aged 18 to 79 years, mean ± SEM 41.9 ± 1.3, completed the study.

Measurements:

Dietary intake was assessed using 3-day food diaries verified with food frequency questionnaires. To assess evenness of protein intake, the day was divided into 3 periods: waking to 11:30, 11:31 to 16:30, and after 16:30. Lean mass was measured with dual energy X-ray absorptiometry. Lower-body muscle strength and endurance were determined using isokinetic dynamometry. Upper-body muscle strength was maximal handgrip strength. Functional ability was assessed using 6-m gait speed and 30-second chair stand tests. Accelerometry measured physical activity.

Results:

Intakes of 25 g or more of protein at 1 or more of the 3 periods was positively associated with lean mass (β ± S.E.; 1.067 ± 0.273 kg, P < .001) and upper-body (3.274 ± 0.737 kg, P < .001) and lower-body strength (22.858 ± 7.918 Nm, P = .004) when controlling for age, body mass index, physical activity, and energy and protein intakes. Consuming at least 0.24 g/kg/period for those under 60 years and 0.4 g/kg/period for those 60 years and older was related to lean mass (0.754 ± 0.244 kg, P = .002), upper-body strength (2.451 ± 0.658 kg, P < .001), and lower-body endurance (184.852 ± 77.185 J, P = .018), controlling for the same variables.

Conclusions:

Evenness of protein intake is related to lean mass, muscle strength, and muscular endurance in women. Spreading protein intake throughout the day maximizes the anabolic response to dietary protein, benefiting muscle mass and performance.

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.

Association between dietary protein intake and changes in health-related quality of life in older adults: findings from the AusDiab 12-year prospective study

Background

Adequate dietary protein intake is recommended for older adults to optimise muscle health and function, and support recovery from illness, however, its effect on health-related quality of life (HRQoL) is unclear. The aim of this study was to examine the association between total protein intake and different sources of dietary protein and HRQoL in Australians aged 60 years and older over a 12-year period.

Methods

This study used data from the Australian Diabetes, Obesity and Lifestyle study (AusDiab), a 12-year population-based prospective study. The sample included 752 (386 females) adults aged 60 years and older. Protein intake was estimated at baseline (1999/2000) from a 74-item Food Frequency Questionnaire, and HRQoL using the 36-item Short-form Health Survey assessed at baseline (1999/2000) and after 12 years (2011/12). The association between protein intake and change in HRQoL was evaluated using multivariate regression analysis adjusted for relevant confounders. The difference in change in HRQoL between participants with total protein intakes of < 1.0 g/kg/day, intakes of between 1.0–1.2 g/kg/day and intakes of > 1.2 g/kg/day were assessed using one-way ANCOVA.

Results

Total protein intake at baseline was not associated with 12-year changes in physical component summary (PCS) or mental component summary (MCS) scores of HRQoL. Higher animal, red meat and processed animal protein intakes were associated with deteriorations in PCS scores after adjusting for relevant confounders (β = − 0.04; 95% CI: − 0.07, −0.01 ; p = 0.009; β = − 0.05; 95% CI: − 0.08, − 0.01; p = 0.018; β = − 0.17; 95% CI: − 0.31, − 0.02; p = 0.027 respectively). Higher red meat protein intake was associated with deteriorations in MCS scores after adjusting for relevant confounders (β = − 0.04; 95% CI: − 0.08, − 0.01; p = 0.011). There was no difference in 12-year changes in PCS or MCS between participants consuming total protein of < 1.0 g/kg/day, 1.0–1.2 g/kg/day and intakes of > 1.2 g/kg/day.

Conclusion

There was no relationship between total dietary protein intake and HRQoL, but higher protein intakes from animal, red meat and processed animal sources were associated with a deterioration in HRQoL scores over 12 years. Due to the number of associations examined and high drop out of older less healthy participants, further research is required to confirm the associations detected in healthy and less healthy participants, with a view to making protein intake recommendations for older adults.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-02894-y.

Effects of resistance exercise and whey protein supplementation on skeletal muscle strength, mass, physical function, and hormonal and inflammatory biomarkers in healthy active older men: a randomised, double-blind, placebo-controlled trial

PURPOSE

To determine the individual and combined effects of 12 weeks of resistance exercise (RE) and whey protein supplementation on skeletal muscle strength (primary outcome), mass and physical function, and hormonal and inflammatory biomarkers in older adults.

METHODS

Thirty-six healthy older men [(mean±SE) age: 67±1 y; BMI: 25.5±0.4 kg/m²] were randomised to either control (CON; n=9), whey protein (PRO; n=9), RE+control (EX+CON; n=9), or RE+whey protein (EX+PRO; n=9) in a double-blinded fashion. Whole-body RE (2 sets of 8 repetitions and 1 set to volitional failure at 80% 1RM) was performed twice weekly. Supplements (PRO, 25 g whey protein isolate; CON, 23.75 g maltodextrin) were consumed twice daily.

RESULTS

EX+CON and EX+PRO increased leg extension (+19±3 kg and +20±3 kg, respectively) and leg press 1RM (+27±3 kg and +39±2 kg, respectively) greater than the CON and PRO groups (P<0.001, Cohen's d=1.50-1.90). RE (EX+CON and EX+PRO groups pooled) also increased fat-free mass (FFM) (+0.9±0.3 kg) and 6-min walk test distance (+21±5 m) and decreased fat mass (-0.4±0.4 kg), and interleukin-6 (-1.0±0.4 pg/mL) and tumor necrosis factor-alpha concentration (-0.7±0.3 pg/mL) greater than non-exercise (CON and PRO groups pooled; P<0.05, Cohen's f=0.37-0.45). Whey protein supplementation (PRO and EX+PRO groups pooled) increased 4-m gait speed greater than control (CON and EX+CON groups pooled) (+0.08±0.03 m/s; P=0.007, f=0.51).

CONCLUSION

RE increased muscle strength, FFM and physical function, and decreased markers of systemic inflammation in healthy active older men. Whey protein supplementation alone increased gait speed. No synergistic effects were observed. This study was registered at clinicaltrials.gov as NCT03299972.

Determining the Influence of Habitual Dietary Protein Intake on Physiological Muscle Parameters in Youth and Older Age

Protein ingestion is a potent stimulator of skeletal muscle protein synthesis (MPS). However, older adults demonstrate resistance to anabolic stimuli. Some evidence has demonstrated that a larger acute protein dose is required in older compared to younger adults to elicit the same synthetic response, suggesting that older adults should be consuming higher habitual dietary protein to optimise muscle mass. However, limited research has explored dietary habits in different age groups or the relationship between habitual dietary intake and mechanistic physiological parameters associated with muscle mass and function. This work investigated the effect of habitual dietary intake in young (n = 10, 25.9 (3.2y)) and older (n = 16, 70.2 (3.2y)) community-dwelling adults (16:10 male: female) on physiological muscle parameters. Dietary intake was assessed using four-day diet diaries. Post-absorptive MPS and MPS responses to feeding (4.25x basal metabolic rate; 16% protein) were determined in muscle biopsies of the m. vastus lateralis via stable isotope tracer ([1, 2^-13C₂]-leucine) infusions with mass-spectrometric analyses. Body composition was measured by dual-energy x-ray absorptiometry. Whole body strength was assessed via 1-repetition maximum assessments. No significant differences in habitual dietary intake (protein, fat, carbohydrate and leucine as g.kgWBLM^-1.day^-1) were observed between age groups. Whole-body lean mass (61.8 ± 9.9 vs. 49.8 ± 11.9 kg, p = 0.01) and knee-extensor strength (87.7 ± 28.3 vs. 56.8 ± 16.4 kg, p = 0.002) were significantly higher in young adults. Habitual protein intake (g.kg^-1.day^-1) was not associated with whole-body lean mass, upper-leg lean mass, whole-body strength, knee-extensor strength, basal MPS or fed-state MPS across both age groups. These findings suggest that differences in muscle mass and strength parameters between youth and older age are not explained by differences in habitual dietary protein intake. Further research with a larger sample size is needed to fully explore these relationships and inform on interventions to mitigate sarcopenia development.

Adequate protein intake in older adults in the context of frailty: cross-sectional results of the Nutrition and Health Survey in Taiwan 2014-2017

BACKGROUND

Emerging evidence suggests that a dietary protein intake higher than the current recommended dietary allowance of 0.8 g/kg body weight (BW)/d may be needed to maintain optimal muscle mass, strength, and function in older adults. However, defining optimal protein intake in this age group remains a challenge.

OBJECTIVE

In this study we sought to describe the dietary protein intake in frail, prefrail, and robust older Taiwanese adults.

METHODS

Data for 1920 older adults were collected from the Nutrition and Health Survey in Taiwan from 2014 to 2017. Dietary intake was assessed using the 24-h recall method. Frailty was determined using the modified Fried's criteria. Body composition was assessed using DXA. Sex-specific dietary protein intakes, measured as values/kg of BW, fat-free mass (FFM), and lean mass (LM), were estimated for the 3 age groups (65-69, 70-79, and ≥80y) and the 3 frailty levels.

RESULTS

In both males (P for trend = 0.034) and females (P for trend = 0.015), there were significant downward trends for protein intake/kg of BW with the severity of frailty. The age-adjusted protein intake/kg of BW was still significant in males (P for trend = 0.009), but no longer in females. This phenomenon was also seen for protein intake at lunch and dinner but not at breakfast. Age-adjusted trends for protein intake/kg FFM or LM were not significant in either sex. The median protein intake in robust older males and females was 1.21 and 1.19 g/kg BW/d, respectively, and the mean intakes were even higher.

CONCLUSION

Median protein intake in robust Taiwanese older adults was approximately 1.2 g/kg BW/d, with higher mean values. The protein adequate intake in Taiwanese older adults was higher than the current recommended daily allowance (RDA) level but within the RDA range derived from the state-of art indicator amino acid oxidation technique.

The Effects of Lifestyle and Diet on Gut Microbiota Composition, Inflammation and Muscle Performance in Our Aging Society

Living longer is associated with an increased risk of chronic diseases, including impairments of the musculoskeletal and immune system as well as metabolic disorders and certain cancers, each of which can negatively affect the relationship between host and microbiota up to the occurrence of dysbiosis. On the other hand, lifestyle factors, including regular physical exercise and a healthy diet, can affect skeletal muscle and immune aging positively at all ages. Accordingly, health benefits could partly depend on the effect of such interventions that influence the biodiversity and functionality of intestinal microbiota. In the present review, we first discuss the physiological effects of aging on the gut microbiota, immune system, and skeletal muscle. Secondly, we describe human epidemiological evidence about the associations between physical activity and fitness and the gut microbiota composition in older adults. The third part highlights the relevance and restorative mechanisms of immune protection through physical activity and specific exercise interventions during aging. Fourth, we present important research findings on the effects of exercise and protein as well as other nutrients on skeletal muscle performance in older adults. Finally, we provide nutritional recommendations to prevent malnutrition and support healthy active aging with a focus on gut microbiota. Key nutrition-related concerns include the need for adequate energy and protein intake for preventing low muscle mass and a higher demand for specific nutrients (e.g., dietary fiber, polyphenols and polyunsaturated fatty acids) that can modify the composition, diversity, and metabolic capacity of the gut microbiota, and may thus provide a practical means of enhancing gut and systemic immune function.

Protein Intake and Cognitive Function in Older Adults: A Systematic Review and Meta-Analysis

Introduction:

The present study investigated the association between protein intake and cognitive function in older adults.

Methods:

We performed a literature search with no restriction on publication year in MEDLINE, SCOPUS, CINAHL, AgeLine from inception up to October 2020. Observational studies that investigated as a primary or secondary outcome the association of protein intake and cognitive function in older adults aged ⩾60 years were included.

Results:

Nine cross-sectional studies that investigated a total of 4929 older adults were included in the qualitative analysis. Overall cognitive function was examined in 6 studies. Four investigations reported null associations and 2 studies found that older adults with a high protein intake had higher global cognitive function than their counterparts. Results from the meta-analysis suggested that there were no significant associations between protein consumption and global cognitive function in older adults, regardless of gender. Three studies investigated other cognitive domains. Memory and protein intake were significantly and positively correlated in all studies. In addition, visuospatial, verbal fluency, processing speed, and sustained attention were positively associated with protein consumption in 1 study each.

Conclusion:

No significant associations between protein intake and global cognitive function were observed in neither qualitative nor quantitative analyses. The association between protein consumption with multiple other cognitive domains were also tested. As a whole, 3 studies reported a positive and significant association between high protein intake and memory, while 1 study observed a significant and positive association with visuospatial, verbal fluency, processing speed, and sustained attention.

High Frequency Protein-Rich Meal Service to Promote Protein Distribution to Stimulate Muscle Function in Preoperative Patients

Apart from meeting daily protein requirements, an even distribution of protein consumption is proposed instrumental to optimizing protein muscle synthesis and preserving muscle mass. We assessed whether a high frequency protein-rich meal service for three weeks contributes to an even daily protein distribution and a higher muscle function in pre-operative patients. This study was a post-hoc analysis of a randomized controlled trial (RCT) in 102 patients. The intervention comprised six protein-rich dishes per day. Daily protein distribution was evaluated by a three-day food diary and muscle function by handgrip strength before and after the intervention. Protein intake was significantly higher in the intervention group at the in-between meals in the morning (7 ± 2 grams (g) vs. 2 ± 3 g, p < 0.05) and afternoon (8 ± 3 g vs. 2 ± 3 g, p < 0.05). Participants who consumed 20 g protein for at least two meals had a significantly higher handgrip strength compared to participants who did not. A high frequency protein-rich meal service is an effective strategy to optimize an even protein distribution across meals throughout the day. Home-delivered meal services can be optimized by offering more protein-rich options such as dairy or protein supplementation at breakfast, lunch and prior to sleep for a better protein distribution.

Protein intake is not associated with functional biomarkers of physical frailty: A cross-sectional analysis of community-dwelling older adults with type 2 diabetes mellitus

BACKGROUND AND AIM

Frailty has emerged as a third category of complication in patients with type 2 diabetes mellitus (T2DM). It has been suggested that adequate protein intake is an important dietary strategy for counteracting frailty. Therefore, we explored the association between protein intake and functional biomarkers of frailty in older adults with T2DM.

METHODS AND RESULTS

Frailty was operationalized as the presence of three of the following: exhaustion, low muscle strength, low physical activity, slow gait speed, and weight loss. Functional biomarkers included handgrip strength (HGS), chair stands, the short physical performance battery and gait speed. Eighty-seven older adults (71.2 ± 8.2 years; 66.7% males) were included. A total of n = 6 (~7%) and n = 32 (~37%) participants were identified as frail and pre-frail respectively. No significant difference was observed for protein intake across staging of frailty (pre-frail/frail: 1.3 ± 0.4 g/kg BW; non-frail: 1.4 ± 0.4 g/kg BW; P = 0.320). A significant association was observed for total protein intake and HGS (β = 0.44; 95% CI: 0.23-1.8; P = 0.01). However, this was no longer significant after adjusting for age, gender, physical activity, energy intake and total appendicular lean muscle (β = 0.03; 95% CI: -0.45-0.60; P = 0.78). Nil other associations were observed between total protein intake and functional biomarkers of frailty.

CONCLUSION

Adequate protein intake was not associated with functional biomarkers in older adults with T2DM. Future research should focus on the efficacy of protein on attenuating functional decline in vulnerable older adults with low protein intake.

Evenness of dietary protein distribution is associated with higher muscle mass but not muscle strength or protein turnover in healthy adults: a systematic review

PURPOSE

Age-related decrease in muscle mass is, among several other factors, caused by suboptimal dietary protein intake. The protein intake of the general population has a skewed distribution towards the evening meal. However, it is hypothesised that an intake of protein with an even meal distribution leads to a more frequently maximised protein synthesis. This review investigates whether an even protein distribution is associated with preservation or gain in muscle mass, muscle strength, and protein turnover.

METHODS

Seven databases: PubMed, Web of Science, Google Scholar, CINAHL, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and Embase were searched. Studies included had a healthy population between 20 and 85 years of age, with a BMI between 18.5 and 30.0, investigated even vs. skewed protein distribution, and measured skeletal muscle relevant outcomes. Case studies and systematic reviews were excluded. Studies were appraised using the AXIS scale for observational studies and the PEDro scale for the remaining studies.

RESULTS

Fifteen studies met the eligibility criteria and were included. Three out of seven studies showed an association between even protein distribution and higher muscle mass. Two out of seven studies showed an association between greater muscle strength and an even protein distribution. Only one out of six studies found a positive association between protein synthesis and an even protein distribution.

CONCLUSION

Evidence indicated an association between muscle mass and an even protein intake. However, the evidence is currently insufficient to conclude whether an even protein intake is positively associated with muscle strength or protein turnover.

Dietary Protein Intake Patterns and Inadequate Protein Intake in Older Adults from Four Countries

Recent interest in protein intake per meal is observed in studies that have reported the protein intake patterns in different countries; however, comparisons of these data are lacking. We aimed to compare protein intake patterns and the percentage of inadequate protein intake (IPI) per day and meal in older adults from different countries. We acquired data of protein intake in older adults from four countries (Mexico, United States of America, Germany, and United Kingdom). We compared protein intake (per day and meal), IPI per day and meal, and the number of meals with an adequate protein content among countries. The IPI per day significantly differed among countries for <0.8 and <1.0 (both p < 0.001), but not for <1.2 g/kg/d (p = 0.135). IPI per meal (<30 g/meal) did not differ among countries at breakfast (p = 0.287) and lunch (p = 0.076) but did differ at dinner (p < 0.001). Conversely, IPI per meal (<0.4 g/kg/meal) significantly differed among countries at breakfast, lunch, and dinner (all p < 0.001). The percentage of participants that ate ≥30 g/meal or ≥0.4 g/kg/meal at zero, one, and two or three meals per day significantly differed among countries (all p < 0.05). IPI at breakfast and lunch (<30 g/meal) was a common trait in the analyzed samples and might represent an opportunity for nutritional interventions in older adults in different countries.

Protein Intake and Frailty: A Matter of Quantity, Quality, and Timing

Frailty is a geriatric syndrome that refers to a state of reduced resiliency to stressful events that occurs in response to physiological and/or psychosocial detriments. Frailty is a predictor of poor prognosis, given that frail older adults are at higher risk of many adverse health-related events. Hence, the identification of potential strategies to prevent the development and progression of frailty is of extreme importance for avoiding its negative outcomes. An adequate protein consumption is advocated as a possible intervention for the management of frailty in older adults due to its effects on muscle mass and physical function. However, empirical evidence is still needed to support this proposition. On the other hand, substantial evidence from observational studies has provided important information on the association between frailty and dietary protein-related parameters. Here, we provide a narrative review of the current literature regarding the association between protein intake (amount (how much?), quality (what type?), and distribution across meals (when?)) and frailty-related parameters. The ultimate aim of this work is to offer practical, evidence-based indications to healthcare professionals responsible for the care of frail older adults.

Daily Protein and Energy Intake Are Not Associated with Muscle Mass and Physical Function in Healthy Older Individuals-A Cross-Sectional Study

Dietary protein has a pivotal role in muscle mass maintenance with advancing age. However, an optimal dose and distribution of protein intake across the day as well as the interaction with energy intake for the maintenance of muscle mass and physical function in healthy older adults remain to be fully elucidated. The purpose of this study was to examine the association between muscle mass, strength, and physical function, and the total amount and distribution of protein and energy intake across the day in healthy older individuals. The research question was addressed in a cross-sectional study including 184 Danish men and woman (age: 70.2 ± 3.9 years, body mass: 74.9 ± 12.1 kg, Body Mass Index (BMI): 25.4 ± 3.7 kg/m²) where a 3-day dietary registration, muscle mass, strength, and functional measurements were collected. We found that neither daily total protein intake nor distribution throughout the day were associated with muscle mass, strength, or physical function. Consequently, we do not provide an incentive for healthy older Danish individuals who already adhere to the current internationally accepted recommended dietary protein intake (0.83 g/kg/day) to change dietary protein intake or its distribution pattern throughout the day.

A Review of Nutritional Requirements of Adults Aged ≥65 Years in the UK

Appropriate dietary choices in later life may reduce the risk of chronic diseases and rate of functional decline, however, there is little well-evidenced age-specific nutritional guidance in the UK for older adults, making it challenging to provide nutritional advice. Therefore, the aim of this critical review was to propose evidence-based nutritional recommendations for older adults (aged ≥65 y). Nutrients with important physiological functions in older adults were selected for inclusion in the recommendations. For these nutrients: 1) recommendations from the UK Scientific Advisory Committee for Nutrition (SACN) reports were reviewed and guidance retained if recent and age-specific, and 2) a literature search conducted where SACN guidance was not sufficient to set or confirm recommendations for older adults, searching Web of Science up to March 2020. Data extracted from a total of 190 selected publications provided evidence to support age-specific UK recommendations for protein (1.2 g·kg-1·d-1), calcium (1000 mg·d-1), folate (400 μg·d-1), vitamin B-12 (2.4 μg·d-1), and fluid (1.6 L·d-1 women, 2.0 L·d-1 men) for those ≥65 y. UK recommendations for carbohydrates, free sugars, dietary fiber, dietary fat and fatty acids, sodium, and alcohol for the general population are likely appropriate for older adults. Insufficient evidence was identified to confirm or change recommendations for all other selected nutrients. In general, significant gaps in current nutritional research among older adults existed, which should be addressed to support delivery of tailored nutritional guidance to this age group to promote healthy aging.

Association between Dietary Habits and Physical Function in Brazilian and Italian Older Women

The present study investigated and compared the patterns of dietary protein intake and physical function in Brazilian and Italian older women. Seventy-five Brazilian older women were recruited in a community senior center. Fifty-three age-matched Italian older women were selected from participants of the Longevity check-up (Lookup) 7+ study. In both samples, physical performance was evaluated by isometric handgrip strength (IHG) and five-time sit-to-stand (5 × STS) tests, while diet was assessed through 24-h recall. Results indicated that Brazilian women had a higher intake of plant-based protein (52.7% vs. 30.5% kcal), while Italian women consumed greater amounts of animal-derived protein (29.7% vs. 41.5% kcal). In Brazilian women, the binary logistic regression analysis indicated that body weight-adjusted protein consumption was associated with IHG adjusted by body mass index and with 5 × STS performance. In the Italian sample, the intake of isoleucine, leucine, and valine was significantly associated with 5 × STS performance. Our findings indicate that Brazilian and Italian community-dwelling older women show different patterns of protein intake, with higher consumption of plant-based protein in the Brazilian sample and higher ingestion of animal-derived protein in the Italian subgroup. These dietary patterns may differentially impact the relationship between physical function and protein intake observed in Brazilian and Italian older women.

Protein intake, weight loss, dietary intervention, and worsening of quality of life in older patients during chemotherapy for cancer

Decreased health-related quality of life (HRQoL) is common in patients with cancer. We investigated the effects of dietary intervention and baseline nutritional status on worsening of HRQoL in older patients during chemotherapy. In this randomized control trial assessing the effect on mortality of dietary advice to increase dietary intake during chemotherapy, this post hoc analysis included 155 patients with cancer at risk of malnutrition. The effects of dietary intervention, baseline Mini Nutritional Assessment item scores, weight loss, and protein and energy intake before treatment on the worsening of HRQoL (physical functioning, fatigue) and secondary outcomes (Timed Up and Go test, one-leg stance time, depressive symptoms, basic (ADL), or instrumental (IADL) activities of daily living) were analyzed by multinomial regressions. Dietary intervention increased total energy and protein intake but had no effect on any examined outcomes. Worsening of fatigue and ADL was predicted by very low protein intake (< 0.8 g kg^-1 day^-1) before chemotherapy (OR 3.02, 95% CI 1.22-7.46, p = 0.018 and OR 5.21, 95% CI 1.18-22.73, p = 0.029 respectively). Increase in depressive symptomatology was predicted by 5.0-9.9% weight loss before chemotherapy (OR 2.68, 95% CI 1.10-6.80, p = 0.038). Nutritional intervention to prevent HRQoL decline during chemotherapy should focus on patients with very low protein intake along with those with weight loss.

Protein Distribution and Muscle-Related Outcomes: Does the Evidence Support the Concept?

There is a shift in thinking about dietary protein requirements from daily requirements to individual meal requirements. Per meal, stimulation of muscle protein synthesis has a saturable dose relationship with the quantity of dietary protein consumed. Protein intake above the saturable dose does not further contribute to the synthetic response; the "excess" amino acids are predominantly oxidized. Given that daily dietary protein intake is finite, finding protein distribution patterns that both reduce amino acid oxidation and maximize their contribution towards protein synthesis (in theory improving net balance) could be "optimal" and is of practical scientific interest to promote beneficial changes in skeletal muscle-related outcomes. This article reviews both observational and randomized controlled trial research on the protein distribution concept. The current evidence on the efficacy of consuming an "optimal" protein distribution to favorably influence skeletal muscle-related changes is limited and inconsistent. The effect of protein distribution cannot be sufficiently disentangled from the effect of protein quantity. Consuming a more balanced protein distribution may be a practical way for adults with marginal or inadequate protein intakes (<0.80 g·kg-1·d-1) to achieve a moderately higher total protein intake. However, for adults already consuming 0.8-1.3 g·kg-1·d-1, the preponderance of evidence supports that consuming at least one meal that contains sufficient protein quantity to maximally stimulate muscle protein synthesis, independent of daily distribution, is helpful to promote skeletal muscle health.

Distribution of daily protein intake across meals and lower extremity functioning in community-dwelling Spanish older adults: a prospective cohort study

PURPOSE

Total dietary protein intake has been associated with better physical function in older adults. However, it is unclear whether an even mealtime distribution of protein intake also has an impact on physical functioning. The aim of this study was to examine the prospective association between distribution of daily protein intake across meals and the risk of impaired lower extremity function (ILEF).

METHODS

We used information of 2975 individuals ≥ 60 years from the Seniors-ENRICA cohort. Habitual dietary protein intake was assessed in 2008-2010 with a validated diet history. For each participant, dietary protein intake across meals was determined using the coefficient of variation (CV) of the distribution. Study participants were followed up until 2017 to identify incident ILEF, assessed with the short physical performance battery (SPPB).

RESULTS

Over a median follow-up of 6.3 years, we identified 521 participants with ILEF (SPPB ≤ 6). After adjusting for potential confounders including total protein intake/kg/day, a higher CV (less even distribution) of protein intake did not show an association with the risk of ILEF [hazard ratios (HR) and 95% confidence intervals (CI) for second and third vs. the first tertile: 1.08 (0.87-1.34), and 1.06 (0.85-1.32), respectively; p trend = 0.60]. When assessing each component of the SPPB, a higher CV of protein intake was associated with higher risk of impaired standing balance (HR for tertile 3 vs. tertile 1: 1.26 (1.03-1.54); p trend = 0.02).

CONCLUSION

The mealtime distribution of protein intake was not associated with ILEF. The possibility of a detrimental effect of uneven distribution of protein on standing balance needs to be further investigated.

Interaction of recommended levels of physical activity and protein intake is associated with greater physical function and lower fat mass in older women: Kuopio Osteoporosis Risk Factor- (OSTPRE) and Fracture-Prevention Study

The aim of the study was to investigate whether the interaction of physical activity (PA) and protein intake is associated with physical function (PF). The women from the Osteoporosis Risk Factor and Fracture Prevention Study (n 610) completed a questionnaire on lifestyle factors and PA and underwent PF and body composition measurements at baseline (BL) and over 3 years of follow-up (3y-FU). PA was categorised according to WHO cut-off PA = 0, 0 < PA < 2·5 and PA ≥ 2·5 h/week. Protein intake was calculated from the 3-d food record at baseline and categorised according to the Nordic Nutrition Recommendations <1·1 and ≥1·1 g/kg body weight (BW). The results showed in univariate ANOVA at the baseline and at the 3-year follow-up, women with high PA ≥ 2·5 h/week and protein intake ≥ 1·1 g/kg BW had higher grip strength adjusted for BMI, higher mean number of chair rises, faster mean walking speed, higher modified mean short physical performance battery score and lower mean fat mass compared with other interaction groups. High PA and protein intake were associated with lower BMI despite significantly higher energy intake. In conclusion, higher PA and protein intake interaction was associated with greater PF and lower fat mass, but the association with relative skeletal muscle index and muscle mass was inconclusive. The present study gives noteworthy information for preventing sarcopenia.

Protein-Related Dietary Parameters and Frailty Status in Older Community-Dwellers across Different Frailty Instruments

The present study investigated the associations between frailty status and (a) daily protein intake, (b) daily body weight-adjusted protein intake, (c) branched-chain amino acid (BCAA) consumption, (d) evenness of protein distribution across main meals, (e) number of daily meals providing at least 30 g of protein, and (f) number of daily meals providing at least 0.4 g protein/kg of body weight in community-dwelling older adults. The relationship between frailty status and protein-related dietary parameters was explored across different frailty assessment tools. Two hundred older adults were enrolled in the study. Participant frailty status was determined according to a modified Fried’s frailty phenotype (mFP), the FRAIL scale, and the Study of Osteoporotic Fracture (SOF) index. Diet was assessed by 24-h dietary recall, while diet composition was estimated using a nutritional software. A frailty instrument-dependent relationship was observed between frailty status and protein-related dietary parameters. Protein consumption was associated with frailty status only in participants identified as frail according to the mFP. In addition, protein and BCAA intake was found to be greater in robust and pre-frail participants relative to their frail counterparts. Our findings suggest that the association between frailty and protein-related dietary parameters is tool dependent. Specifically, protein and BCAA consumption appears to be lower only in older adults identified as frail by the mFP.

The Consumption of Two or Three Meals per Day with Adequate Protein Content Is Associated with Lower Risk of Physical Disability in Mexican Adults Aged 60 Years and Older

Adequate protein intake per day has been associated with a lower risk of physical disability; however, if adequate protein intake per meal is also associated is unknown. The purpose of this study was to analyze the association between adequate protein intake per meal and physical disability in daily living activities in Mexican adults aged ≥60 years. We assessed the number of meals per day with an adequate protein content (24 h dietary recall), the presence of physical disability in daily living activities (two validated questionnaires), and their association in 187 participants through logistic regression. Consuming two or three meals per day with ≥30 g each was associated with lower risk of physical disability on Transportation (OR [95% CI]: 0.06 [0.01–0.50], p = 0.01), Shopping (0.05 [0.01–0.40], p = 0.004), Feeding (0.06 [0.01–0.74], p = 0.028), and Transfer (0.09 [0.01–0.98], p = 0.048). On the other hand, consuming two or three meals per day with ≥0.4 g/kg each was associated with lower risk of physical disability on Shopping (0.21 [0.05–0.89], p = 0.034) and Transportation (0.12 [0.03–0.48], p = 0.003). The consumption of two or three meals per day with adequate protein content is associated with lower risk of physical disability in Mexican adults aged 60 years and older.

A Review of the Development and Application of Generic Preference-Based Instruments with the Older Population

Older people (aged 65 years and over) are the fastest growing age cohort in the majority of developed countries, and the proportion of individuals defined as the oldest old (aged 80 years and over) living with physical frailty and cognitive impairment is rising. These population changes put increasing pressure on health and aged care services, thus it is important to assess the cost effectiveness of interventions targeted for older people across health and aged care sectors to identify interventions with the strongest capacity to enhance older peoples' quality of life and provide value for money. Cost-utility analysis (CUA) is a form of economic evaluation that typically uses preference-based instruments to measure and value health-related quality of life for the calculation of quality-adjusted life-years (QALYS) to enable comparisons of the cost effectiveness of different interventions. A variety of generic preference-based instruments have been used to measure older people's quality of life, including the Adult Social Care Outcomes Toolkit (ASCOT); Health Utility Index Mark 2 (HUI2); Health Utility Index Mark 3 (HUI3); Short-Form-6 Dimensions (SF-6D); Assessment of Quality of Life-6 dimensions (AQoL-6D); Assessment of Quality of Life-8 dimensions (AQoL-8D); Quality of Wellbeing Scale-Self-Administered (QWB-SA); 15 Dimensions (15D); EuroQol-5 dimensions (EQ-5D); and an older person specific preference-based instrument-the Investigating Choice Experiments Capability Measure for older people (ICECAP-O). This article reviews the development and application of these instruments within the older population and discusses the issues surrounding their use with this population. Areas for further research relating to the development and application of generic preference-based instruments with populations of older people are also highlighted.

Basal Metabolic Rate and Body Composition Predict Habitual Food and Macronutrient Intakes: Gender Differences

The underlying mechanisms that regulate energy homeostasis and food intake are not fully understood. Moreover, little research has been performed on the relation of body composition with habitual macronutrient intake among free-living populations. Since body composition and energy metabolism differ between males and females, we aimed to determine whether the relationship between body composition and habitual macronutrient intakes is gender-dependent. In this cross-sectional study, 261 participants (99 males) were recruited from Singapore. Macronutrient intake was evaluated from a three-day self-reported dietary record. Body composition and basal metabolic rate (BMR) were determined by using dual-energy X-ray absorptiometry (DEXA) and indirect calorimetry, respectively. Our results show that both BMR (p < 0.001) and lean body mass (LBM, p < 0.001) predicted daily energy intake (EI). LBM was positively associated with intakes of protein (PRO) and fat (FAT) in females, but not in males. This relationship persisted even after adjustment for fat mass (FM). On the other hand, no significant associations between FM and macronutrient intake were observed in both males and females. Therefore, the relationship between habitual macronutrient intake, LBM, and BMR is gender-dependent. Elucidating the gender differences in energy metabolism is important for understanding the factors that regulate energy homeostasis and can subsequently help better manage energy balance.

Daily Protein Intake and Distribution of Daily Protein Consumed Decreases Odds for Functional Disability in Older Americans

Objective: We sought to determine whether daily protein intake and protein distribution across eating occasions were associated with functional disability in a national sample of older Americans. Methods: Data from 8,070 adults aged ≥60 years from the 2007-2016 waves of the National Health and Nutrition Examination Survey were included. Protein intake and functional capacity was self-reported. A daily protein recommendation of ≥1.0 g/kg/day was utilized. The daily protein recommendation was then spread-out across four meals, whereby a ≥0.25 g/kg/meal threshold was used. Results: Those meeting the daily protein recommendation had 0.78 (95% confidence interval [CI] = [0.65, 0.93]) decreased odds for functional disability. Persons meeting the protein intake threshold per eating occasion for one, two, three, and four occasions had 0.60 (CI = [0.38, 0.95]), 0.48 (CI = [0.30, 0.77]), 0.47 (CI = [0.29, 0.77]), and 0.39 (CI = [0.20, 0.75]) decreased odds for functional disability, respectively. Discussion: Protein consumption seems to be important for preserving function in older Americans.

High relative consumption of vegetable protein is associated with faster walking speed in well-functioning older adults

BACKGROUND

Adequate nutrition and, especially, optimal protein intake are necessary to preserve physical function during aging. Increased consumption of animal-derived protein is often advocated as a strategy to support physical performance in old age. However, there is a lack of empirical evidence to support this claim.

AIMS

To assess the relationship of protein consumption and specific protein sources with physical function in older adults.

METHODS

Participants were community dwellers aged 60 years and older recruited in São Paulo, Brazil. Enrollees had their medical books reviewed and were evaluated for anthropometry, physical performance, and diet. Physical performance was evaluated by isometric handgrip strength and walking speed (WS) tests. Diet was assessed using a 24-h recall diary.

RESULTS

Ninety older adults were recruited (mean age: 68.0 ± 6.7 years; 87.0% women). Body weight-adjusted protein consumption was significantly associated with upper-limb muscle strength (r = 0.21; p < 0.05), but not with usual (r = 0.09; p > 0.05) or fast WS (r = 0.08; p > 0.05). Conversely, relative protein consumption was correlated with usual WS (r = 0.13; p < 0.05), while fast WS was negatively associated with relative animal protein intake (r = - 0.18; p < 0.05) and positively associated with relative plant-based protein ingestion (r = 0.15; p < 0.05).

DISCUSSION

Findings of the present study indicate that different measures of protein intake are associated with distinct components of physical function. In addition, high relative ingestion of vegetable protein is associated with faster WS.

CONCLUSIONS

A comprehensive dietary evaluation is necessary to appreciate the impact of specific nutrients on physical performance in older people. Future interventional studies are needed to establish the optimal blend of protein sources to support physical performance in old age.

Triple Adaptation of the Mediterranean Diet: Design of A Meal Plan for Older People with Oropharyngeal Dysphagia Based on Home Cooking

BACKGROUND

Oropharyngeal dysphagia (OD) and malnutrition are highly prevalent in older patients that are discharged from general hospitals (47% and 30%, respectively).

AIMS

To develop a nutritional plan for these patients involving a triple adaptation of their traditional diet: (a) rheological adaptation (texture and viscosity) for safe deglutition, (b) nutritional adaptation (water, calories, and proteins), and (c) organoleptic adaptation to improve compliance.

METHODS

Two fluid viscosities (250 and 800 mPa·s) were selected according to previous studies on optimal viscosities in older patients. The British Dietetic Association food texture classification based on common clinical practice selected two food textures (thick purée and fork-mashable. Two levels of calorie protein enrichment were selected according to previous studies using the Mini Nutritional Assessment (MNA®).

RESULTS

The daily caloric-protein and hydric needs were established at 1750 kcal, 70 g protein, and 1750 mL water in patients with MNA® ≥ 17; and, 2037 kcal, 90 g protein, and 2000 mL water/day in malnourished patients. Sixteen weekly menus (296 recipes) were developed while using two textures, two levels of viscosity, two nutritional phenotypes (normal/at-risk vs. malnourished), and two seasons of the year (spring/summer-autumn/winter) based on Mediterranean cuisine.

CONCLUSION

This concept paper demonstrates that traditional Mediterranean cooking can be adapted to meet the rheological, nutritional, and hydration needs of older patients with OD. The recipes that we have developed meet the needs of patients with varying degrees of OD and malnutrition are reproducible in patient's homes and they could have a major impact on the clinical outcomes of these patients.

Food Products as Sources of Protein and Amino Acids-The Case of Poland

The aim of this study was to identify the food sources of protein and 18 amino acids (AAs) in the average Polish diet. The analysis was conducted based on the 2016 Household Budget Survey (HBS) on the consumption of food products from a representative sample of 38,886 households (n = 99,230). This survey was organized, conducted and controlled by the Central Statistical Office, Social Surveys and Living Conditions Statistics Department in cooperation with the Statistic Office in Łódź based on the recording of expenditures, quantitative consumption, and revenues in budget books for one month. 91 food products from 13 food categories (e.g., meat and meat products, grain products) consisting of 42 food groups (e.g., red meat, milk, cheese) were analyzed to determine protein and amino acid intake from these products. Three categories delivered 80.9% of total protein (meat and meat products: 38.9%; grain products: 23.9%; and milk and dairy products: 18.1%). The branched-chain amino acids (BCAAs: leucine, isoleucine and valine) were delivered mainly by meat and meat products (39.9%; 41.3% and 37.4%, respectively). Meat and meat products were also the most important source for other essential amino acids (EAAs: lysine 49.2%, histidine 46.6%, threonine 44.7%, tryptophan 41.4%, phenylalanine 35.3%, and methionine 44.2%). In terms of the contribution of the non-essential or conditionally essential amino acids to the average Polish diet, most important were grain products (for cysteine: 41.2%; glutamic acid: 33.8%; proline: 34.1%), and meat and meat products (for tyrosine: 38.3%; arginine: 46.1%; alanine: 48.7%; aspartic acid: 41.7%; glycine: 52.5%; serine: 33.6%). Five clusters were identified to assess the impact of socio-demographic and economic factors on the protein supply. The largest impact was observed for respondent education, degree of urbanization, study month, and usage of agricultural land. The shares of animal food in total protein supply amounted to 66.5% in total population and varied from 56.4% to 73.6% in different clusters.

Relative Protein Intake and Physical Function in Older Adults: A Systematic Review and Meta-Analysis of Observational Studies

(1) Background: The present work aims to conduct a systematic review and meta-analysis of observational studies, in order to investigate the association of relative protein intake and physical function in older adults; (2) Methods: Observational studies, that investigated the association between protein intake and physical function in older adults, were retrieved from MEDLINE, SCOPUS, CINAHL, AgeLine, EMBASE, and Cochrane-CENTRAL. Two independent researchers conducted study selection and data extraction; (3) Results: Very high protein intake (≥1.2 g/kg/day) and high protein intake (≥1.0 g/kg/day) groups showed better lower limb physical functioning and walking speed (WS) performance, respectively, in comparison to individuals who present relative low protein (<0.80 g/kg/day) intake. On the other hand, relative high protein intake does not seem to propitiate a better performance on isometric handgrip (IHG) and chair rise in comparison to relative low protein intake. In addition, there were no significant differences in the physical functioning of high and middle protein intake groups; (4) Conclusions: In conclusion, findings of the present study indicate that a very high (≥1.2 g/kg/day) and high protein intake (≥1.0 g/kg/day) are associated with better lower-limb physical performance, when compared to low protein (<0.80 g/kg/day) intake, in community-dwelling older adults. These findings act as additional evidence regarding the potential need to increase protein guidelines to above the current recommendations. However, large randomized clinical trials are needed to confirm the addictive effects of high-protein diets (≥1.0 g/kg/day) in comparison to the current recommendations on physical functioning. All data are available in the Open ScienceFramework.

Low Protein Intake Is Associated with Frailty in Older Adults: A Systematic Review and Meta-Analysis of Observational Studies

(1) Background: Several factors have been suggested to be associated with the physiopathology of frailty in older adults, and nutrition (especially protein intake) has been attributed fundamental importance in this context. The objective of this study was to conduct a systematic review and meta-analysis to investigate the relationship between protein intake and frailty status in older adults. (2) Methods: A search of scientific studies was conducted in the main databases (Medline, Scopus, Cochrane library), and in the reference lists of selected articles. The search terms included synonyms and Medical Subject Headings and involved the use of Boolean operators which allowed the combination of words and search terms. Observational studies-cross-sectional and longitudinal-that met the eligibility criteria were included in the review. Article selection and data extraction were performed by two independent reviewers. Meta-analyses with random effects were performed. Publication bias was measured using the Strengthening the Reporting of Observational Studies in Epidemiology instrument. (3) Results: In the final sample, 10 articles, seven cross-sectional and three longitudinal, were included in the present study. Overall, studies investigated a total of 50,284 older adults from three different continents between 2006 and 2018. Four cross-sectional studies were included in the meta-analyses. The results demonstrated that a high protein intake was negatively associated with frailty status in older adults (odds ratio: 0.67, confidence interval = 0.56 to 0.82, p = 0.0001). (4) Conclusions: Our findings suggest that a high consumption of dietary protein is inversely associated with frailty in older adults.

Impact of Meeting Different Guidelines for Protein Intake on Muscle Mass and Physical Function in Physically Active Older Women

The role of dietary protein intake on muscle mass and physical function in older adults is important for the prevention of age-related physical limitations. The aim of the present study was to elucidate links between dietary protein intake and muscle mass and physical function in older women meeting current guidelines of objectively assessed physical activity. In 106 women (65 to 70 years old), protein intake was assessed using a 6-day food record and participants were classified into high and low protein intake groups using two Recommended Dietary Allowance (RDA) thresholds (0.8 g·kg⁻¹ bodyweight (BW) and 1.1 g·kg⁻¹ BW). Body composition, aerobic fitness, and quadriceps strength were determined using standardized procedures, and self-reported physical function was assessed using the SF-12 Health Survey. Physical activity was assessed by accelerometry and self-report. Women below the 0.8 g·kg⁻¹ BW threshold had a lower muscle mass (p < 0.05) with no differences in physical function variables. When based on the higher RDA threshold (1.1 g·kg⁻¹ BW), in addition to significant differences in muscle mass, women below the higher threshold had a significantly (p < 0.05) higher likelihood of having physical limitations. In conclusion, the present study supports the RDA threshold of 0.8 g·kg⁻¹ BW of proteins to prevent the loss of muscle mass and emphasizes the importance of the higher RDA threshold of at least 1.1 g·kg⁻¹ BW to infer additional benefits on constructs of physical function. Our study also supports the role of protein intake for healthy ageing, even in older adults meeting guidelines for physical activity.

An Update on Protein, Leucine, Omega-3 Fatty Acids, and Vitamin D in the Prevention and Treatment of Sarcopenia and Functional Decline

Aging is associated with sarcopenia and functional decline, leading to frailty and disability. As a modifiable risk factor, nutrition may represent a target for preventing or postponing the onset of these geriatric conditions. Among nutrients, high-quality protein, leucine, vitamin D, and omega-3 polyunsaturated fatty acids (n-3 PUFA) are of particular interest for their demonstrated effects on skeletal muscle health. This narrative review aims to examine the recent observational and interventional evidence on the associations and the role of these nutrients in the muscle mass, strength, mobility, and physical function of free-living older adults, who are either healthy or at risk of frailty. Recent evidence supports a higher protein intake recommendation of 1.0⁻1.2 g/kg/day in healthy older adults; an evenly distributed mealtime protein intake or minimal protein per meal may be beneficial. In addition, vitamin D supplementation of 800⁻1000 IU, particularly when vitamin D status is low, and doses of ~3 g/day of n-3 PUFA may be favorable for physical function, muscle mass, and strength. Reviewed studies are highly heterogenous, yet the quantity, quality, and timing of intakes should be considered when designing intervention studies. Combined protein, leucine, vitamin D, and n-3 PUFA supplements may convey added benefits and may represent an intervention strategy in the prevention of sarcopenia and functional decline.