Health effects of protein intake in healthy elderly populations: a systematic literature review

Meat consumption and the risk of hip fracture in women and men: two prospective Swedish cohort studies

PURPOSE

To study the association between meat intake (predominantly red and processed meats) and the risk of hip fracture, as well as the association between meat intake and biomarkers of inflammation, oxidative stress, bone turnover, body composition, and bone mineral density (BMD).

METHODS

Data from the Swedish Mammography Cohort and the Cohort of Swedish men (n = 83,603, 54% men) with repeated investigations and their respective clinical sub-cohorts was utilised. Incident hip fractures were ascertained through individual linkage to registers. Associations were investigated using multivariable Cox and linear regression analyses.

RESULTS

During up to 23 years of follow-up (mean 18.2 years) and 1,538,627 person-years at risk, 7345 participants (2840 men) experienced a hip fracture. Each daily serving of meat intake conferred a hazard ratio (HR) of 1.03 (95% confidence interval [CI] 1.00; 1.06) for hip fracture. In quintile 5, compared to quintile 2, the HR was 1.11 (95% CI 1.01; 1.21) among all participants. In the sub-cohorts, meat intake was directly associated with circulating levels of interleukin-6, C-reactive protein, leptin, ferritin, parathyroid hormone, and calcium.

CONCLUSION

A modest linear association was found between a higher meat intake and the risk of hip fractures. Our results from the sub-cohorts further suggest that possible mechanisms linking meat intake and hip fracture risk may be related to the regulation of bone turnover, subclinical inflammation, and oxidative stress. Although estimates are modest, limiting red and processed meat intake in a healthy diet is advisable to prevent hip fractures.

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.

Protein intake and bone health: an umbrella review of systematic reviews for the evidence-based guideline of the German Nutrition Society

This umbrella review aimed at assessing whether a protein intake exceeding the current recommendation for younger (0.8 g/kg body weight [BW]/day) and older (1.0 g/kg BW/day) adults affects bone mineral density and fracture risk. Moreover, the effect of animal or plant protein was evaluated. A systematic literature search was conducted in PubMed, Embase, and Cochrane Database of Systematic Reviews for systematic reviews (SRs) with or without meta-analysis of prospective studies published between 11/2008 and 08/2021. Methodological quality, outcome-specific certainty of evidence, and overall certainty of evidence of the retrieved SRs were assessed using established tools and predefined criteria. Eleven SRs of randomized controlled trials (RCTs) and/or cohort studies were included. In SRs of cohort studies and RCTs, protein intake/kg BW/day ranged between 0.21-0.95 g (low intake) and > 1.24 g (high intake), respectively, and between 0.67-1.1 g (control groups) and 1.01-1.69 g (intervention groups), respectively. The vast majority of outcome-specific certainty of evidence was rated "low" or "very low." The overall certainty of evidence for an association (cohort studies) or effect (RCTs) of total, animal or plant protein intake on each of the investigated outcomes was rated "insufficient," with the exception of possible evidence for a reduced hip fracture risk by high vs. low protein intake. Since protein intakes in low/control and high/intervention groups were very heterogeneous and with low certainty of evidence, it remains unclear whether a dose above the current recommendation or type of protein intake (animal or plant protein) affects bone health overall. However, there is possible evidence for reduced hip fracture risk with high versus low protein intake.

A Randomized, Double-Blind, Controlled Trial Assessing If Medium-Chain Triglycerides in Combination with Moderate-Intensity Exercise Increase Muscle Strength in Healthy Middle-Aged and Older Adults

An adequate nutritional intake is recommended for the prevention of physical frailty and sarcopenia. In particular, medium-chain fatty acids (MCFAs) are reportedly important for muscle strength in nursing home residents. However, the effects of MCFAs on healthy adults at risk for frailty remain unknown. Hence, a randomized, placebo-controlled study was conducted to investigate the effects of 12 weeks of medium-chain triglycerides (MCTs) intake and walking on muscle mass and function in healthy, sedentary, middle-aged and older adults with a low body mass index. Three MCT intake groups with different amounts of octanoic and decanoic acid intake were compared with a control group. After 12 weeks, knee extension strength increased in all groups, with the increases in all MCT intake groups being significantly higher than those in the control group (p < 0.05). Grip strength significantly increased from baseline in the MCT 6 g/day intake group (p < 0.05). The combination of aerobic exercise and MCT intake may be effective in preventing decline in muscle strength and promoting increase in muscle strength as they can improve muscle energy production, thereby contributing to the maintenance of good health for middle-aged and older adults at high risk for frailty and sarcopenia.

Dietary protein requirements and recommendations for healthy older adults: a critical narrative review of the scientific evidence

Adequate protein intake is essential for the maintenance of whole-body protein mass. Different methodological approaches are used to substantiate the evidence for the current protein recommendations, and it is continuously debated whether older adults require more protein to counteract the age-dependent loss of muscle mass, sarcopenia. Thus, the purpose of this critical narrative review is to outline and discuss differences in the approaches and methodologies assessing the protein requirements and, hence, resulting in controversies in current protein recommendations for healthy older adults. Through a literature search, this narrative review first summarises the historical development of the Food and Agriculture Organization/World Health Organization/United Nations University setting of protein requirements and recommendations for healthy older adults. Hereafter, we describe the various types of studies (epidemiological studies and protein turnover kinetic measurements) and applied methodological approaches founding the basis and the different recommendations with focus on healthy older adults. Finally, we discuss important factors to be considered in future studies to obtain evidence for international agreement on protein requirements and recommendations for healthy older adults. We conclude by proposing future directions to determine 'true' protein requirements and recommendations for healthy older adults.

Evidence-based European recommendations for the dietary management of diabetes

Diabetes management relies on effective evidence-based advice that informs and empowers individuals to manage their health. Alongside other cornerstones of diabetes management, dietary advice has the potential to improve glycaemic levels, reduce risk of diabetes complications and improve health-related quality of life. We have updated the 2004 recommendations for the nutritional management of diabetes to provide health professionals with evidence-based guidelines to inform discussions with patients on diabetes management, including type 2 diabetes prevention and remission. To provide this update we commissioned new systematic reviews and meta-analyses on key topics, and drew on the broader evidence available. We have strengthened and expanded on the previous recommendations to include advice relating to dietary patterns, environmental sustainability, food processing, patient support and remission of type 2 diabetes. We have used the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach to determine the certainty of evidence for each recommendation based on findings from the commissioned and identified systematic reviews. Our findings indicate that a range of foods and dietary patterns are suitable for diabetes management, with key recommendations for people with diabetes being largely similar for those for the general population. Important messages are to consume minimally processed plant foods, such as whole grains, vegetables, whole fruit, legumes, nuts, seeds and non-hydrogenated non-tropical vegetable oils, while minimising the consumption of red and processed meats, sodium, sugar-sweetened beverages and refined grains. The updated recommendations reflect the current evidence base and, if adhered to, will improve patient outcomes.

Even or skewed dietary protein distribution is reflected in the whole-body protein net-balance in healthy older adults: A randomized controlled trial

BACKGROUND & AIM

For older adults, the dietary protein intake has shown to be skewed towards the evening meal. Resultingly, the vital source of essential amino acids could be insufficient after some meals, while after the evening meal the dietary protein could be suboptimally utilized for protein synthesis. The present study explored if an even distribution of the protein intake could improve the dietary amino acid absorption and whole-body protein net-balance.

METHODS

Twenty-four healthy elderly males and females were included in a randomized controlled trial. Ten days of habituation to either an EVEN (n = 12) or SKEWED (n = 12) protein intake, was followed by a trial day. The total protein intake was controlled at 1.5 g/kg LBM, divided into 30% at each main meal in EVEN, and into 15% at breakfast and lunch and 60% at dinner in SKEWED. Snacks with 5% of the protein intake were served between meals. Energy intake in the meals and snacks were equal in both groups. Intrinsically labelled ²H₅-phenylalanine minced meat was served as the dietary protein to assess the amino acid absorption. On the trial day, infusion of ²H₈-phenylalanine and ²H₂-tyrosine, and blood samples taken over 11 h were used to measure whole-body protein turnover. Vastus lateralis muscle biopsies were taken to measure 9 h muscle protein FSR.

RESULTS

Amino acid absorption rates and concentrations were greater in EVEN compared to SKEWED protein intake. Whole-body protein breakdown rates were lower with similar protein synthesis rates, and consequently the net-balance was greater in EVEN after breakfast and lunch compared to SKEWED and were the same in both groups after dinner. Muscle protein FSR were not different between EVEN and SKEWED.

CONCLUSIONS

The whole-body protein net-balance was more positive in EVEN compared to SKEWED for an extended time of the measured period, driven by a lower whole-body protein breakdown in EVEN.

CLINICAL TRIALS REGISTRATION

NCT03870425, https://clinicaltrials.gov/ct2/show/NCT03870425.

Risk of Malnutrition and Insufficient Protein Intake among Older People Living at Home: Baseline Findings of the Power Meals Study

This study aimed to investigate the nutritional status, nutrient intake and associated factors among older home care clients, caregivers and care recipients (≥65 years) living at home. There were a total of 78 participants, with a mean age of 78 ± 7.4 years. Nutritional status was assessed with the Mini Nutritional Assessment (MNA), nutrient intake with a three-day food record, sarcopenia with a Simple Questionnaire to Rapidly Diagnose Sarcopenia (SARC) and depression with The Geriatric Depression Scale (GDS-15). Almost one-third (32.1%) were at risk of malnutrition and 2.6% suffered from malnutrition. Impaired nutritional status was associated with depressive symptoms (β = -0.277, p = 0.015) and risk of sarcopenia (SARC points) (β = -0.401, p = 0.001). Mean protein intake was 0.9 ± 0.3 g/adjusted body weight/day. Intakes of protein and multiple vitamins and minerals were lower than recommended. In conclusion, a third of older people living at home were at risk of malnutrition or malnourished. Multiple physical, psychological and social factors in older adults were associated with nutritional status and protein intake.

An integrative approach to dietary balance across the life course

Animals require specific blends of nutrients that vary across the life course and with circumstances, e.g., health and activity levels. Underpinning and complicating these requirements is that individual traits may be optimized on different dietary compositions leading to nutrition-mediated trade-offs among outcomes. Additionally, the food environment may constrain which nutrient mixtures are achievable. Natural selection has equipped animals for solving such multi-dimensional, dynamic challenges of nutrition, but little is understood about the details and their theoretical and practical implications. We present an integrative framework, nutritional geometry, which models complex nutritional interactions in the context of multiple nutrients and across levels of biological organization (e.g., cellular, individual, and population) and levels of analysis (e.g., mechanistic, developmental, ecological, and evolutionary). The framework is generalizable across different situations and taxa. We illustrate this using examples spanning insects to primates and settings (laboratory, and the wild), and demonstrate its relevance for human health.

Dietary protein and amino acid restriction: Roles in metabolic health and aging-related diseases

The prevalence of obesity is a worldwide phenomenon in all age groups and is associated with aging-related diseases such as type 2 diabetes, as well metabolic and cardiovascular diseases. The use of dietary restriction (DR) while avoiding malnutrition has many profound beneficial effects on aging and metabolic health, and dietary protein or specific amino acid (AA) restrictions, rather than overall calorie intake, are considered to play key roles in the effects of DR on host health. Whereas comprehensive reviews of the underlying mechanisms are limited, protein restriction and methionine (Met) restriction improve metabolic health and aging-related neurodegenerative diseases, and may be associated with FGF21, mTOR and autophagy, improved mitochondrial function and oxidative stress. Circulating branched-chain amino acids (BCAAs) are inversely correlated with metabolic health, and BCAAs and leucine (Leu) restriction promote metabolic homeostasis in rodents. Although tryptophan (Trp) restriction extends the lifespan of rodents, the Trp-restricted diet is reported to increase inflammation in aged mice, while severe Trp restriction has side effects such as anorexia. Furthermore, inadequate protein intake in the elderly increases the risk of muscle-centric health. Therefore, the restriction of specific AAs may be an effective and executable dietary manipulation for metabolic and aging-related health in humans, which warrants further investigation to elucidate the underlying mechanisms.

Nutrition and Healthy Aging: Prevention and Treatment of Gastrointestinal Diseases

Nutritional well-being is a fundamental aspect for the health, autonomy and, therefore, the quality of life of all people, but especially of the elderly. It is estimated that at least half of non-institutionalized elderly people need nutritional intervention to improve their health and that 85% have one or more chronic diseases that could improve with correct nutrition. Although prevalence estimates are highly variable, depending on the population considered and the tool used for its assessment, malnutrition in the elderly has been reported up to 50%. Older patients are particularly at risk of malnutrition, due to multiple etiopathogenetic factors which can lead to a reduction or utilization in the intake of nutrients, a progressive loss of functional autonomy with dependence on food, and psychological problems related to economic or social isolation, e.g., linked to poverty or loneliness. Changes in the aging gut involve the mechanical disintegration of food, gastrointestinal motor function, food transit, intestinal wall function, and chemical digestion of food. These alterations progressively lead to the reduced ability to supply the body with adequate levels of nutrients, with the consequent development of malnutrition. Furthermore, studies have shown that the quality of life is impaired both in gastrointestinal diseases, but especially in malnutrition. A better understanding of the pathophysiology of malnutrition in elderly people is necessary to promote the knowledge of age-related changes in appetite, food intake, homeostasis, and body composition in order to better develop effective prevention and intervention strategies to achieve healthy aging.

Health Effects of Increasing Protein Intake Above the Current Population Reference Intake in Older Adults: A Systematic Review of the Health Council of the Netherlands

Whether older adults need more protein than younger adults is debated. The population reference intake for adults set by the European Food Safety Authority is 0.83 g/kg body weight (BW)/d based primarily on nitrogen balance studies, but the underlying data on health outcomes are outdated. An expert committee of the Health Council of the Netherlands conducted a systematic review (SR) of randomized controlled trials (RCTs) examining the effect of increased protein intake on health outcomes in older adults from the general population with an average habitual protein intake ≥0.8 g/(kg BW · d). Exposures were the following: 1) extra protein compared with no protein and 2) extra protein and physical exercise compared with physical exercise. Outcomes included lean body mass, muscle strength, physical performance, bone health, blood pressure, serum glucose and insulin, serum lipids, kidney function, and cognition. Data of >1300 subjects from 18 RCTs were used. Risk of bias was judged as high (n = 9) or "some concerns" (n = 9). In 7 of 18 RCTs, increased protein intake beneficially affected ≥1 of the tested outcome measures of lean body mass. For muscle strength, this applied to 3 of 8 RCTs in the context of physical exercise and in 1 of 7 RCTs without physical exercise. For the other outcomes, <30% (0-29%) of RCTs showed a statistically significant effect. The committee concluded that increased protein intake has a possible beneficial effect on lean body mass and, when combined with physical exercise, muscle strength; likely no effect on muscle strength when not combined with physical exercise, or on physical performance and bone health; an ambiguous effect on serum lipids; and that too few RCTs were available to allow for conclusions on the other outcomes. This SR provides insufficiently convincing data that increasing protein in older adults with a protein intake ≥0.8 g/(kg BW · d) elicits health benefits.

The Nordic Nutrition Recommendations 2022 - prioritisation of topics for de novo systematic reviews

Background

As part of the process of updating national dietary reference values (DRVs) and food-based dietary guidelines (FBDGs), the Nordic Nutrition Recommendations 2022 project (NNR2022) will select a limited number of topics for systematic reviews (SRs).

Objective

To develop and transparently describe the results of a procedure for prioritisation of topics that may be submitted for SRs in the NNR2022 project.

Design

In an open call, scientists, health professionals, national food and health authorities, food manufacturers, other stakeholders and the general population in the Nordic and Baltic countries were invited to suggest SR topics. The NNR2022 Committee developed scoping reviews (ScRs) for 51 nutrients and food groups aimed at identifying potential SR topics. These ScRs included the relevant nominations from the open call. SR topics were categorised, ranked and prioritised by the NNR2022 Committee in a modified Delphi process. Existing qualified SRs were identified to omit duplication.

Results

A total of 45 nominations with suggestion for more than 200 exposure-outcome pairs were received in the public call. A number of additional topics were identified in ScRs. In order to omit duplication with recently qualified SRs, we defined criteria and identified 76 qualified SRs. The NNR2022 Committee subsequently shortlisted 52 PI/ECOTSS statements, none of which overlapped with the qualified SRs. The PI/ECOTSS statements were then graded 'High' (n = 21), 'Medium' (n = 9) or 'Low' (n = 22) importance, and the PI/ECOTSS statements with 'High' were ranked in a Delphi process. The nine top prioritised PI/ECOTSS included the following exposure-outcome pairs: 1) plant protein intake in children and body growth, 2) pulses/legumes intake, and cardiovascular disease and type 2 diabetes, 3) plant protein intake in adults, and atherosclerotic/cardiovascular disease and type 2 diabetes, 4) fat quality and mental health, 5) vitamin B12 and vitamin B12 status, 6) intake of white meat (no consumption vs. high consumption and white meat replaced with red meat), and all-cause mortality, type 2 diabetes and risk factors, 7) intake of n-3 LPUFAs from supplements during pregnancy, and asthma and allergies in the offspring, 8) nuts intake and cardiovascular disease (CVD) and type 2 diabetes in adults, 9) dietary fibre intake (high vs. low) in children and bowel function.

Discussion

The selection of topics for de novo SRs is central in the NNR2022 project, as the results of these SRs may cause adjustment of existing DRVs and FBDGs. That is why we have developed this extensive process for the prioritisation of SR topics. For transparency, the results of the process are reported in this publication.

Conclusion

The principles and methodologies developed in the NNR2022 project may serve as a framework for national health authorities or organisations when developing national DRVs and FBDGs. This collaboration between the food and health authorities in Denmark, Estonia, Finland, Iceland, Latvia, Lithuania, Norway and Sweden represents an international effort for harmonisation and sharing of resources and competence when developing national DRVs and FBDGs.

Postprandial amino acid availability after intake of intact or hydrolyzed meat protein in a mixed meal in healthy elderly subjects: a randomized, single blind crossover trial

The absorption of dietary proteins affects the anabolic response, among others protein synthesis. For elderly, optimal amino acid absorption is warranted to preserve the amino acid pool of the body, especially skeletal muscle proteins. Therefore, the aim of this study was to characterize if hydrolyzing meat protein (HMP) would improve the amino acid absorption after ingestion of meat compared to equal amounts of the same meat proteins but present in a different structure; steak or minced meat. With a crossover study design on 12 healthy older adults (> 65 years of age, BMI 18.5-30), the amino acid absorption kinetics were explored by ingesting 0.55 g protein/kg LBM as a mixed meal together with intrinsically [²H₅]phenylalanine labeled meat proteins prepared as a STEAK, MINCED meat, or HMP. Plasma [²H₅]phenylalanine enrichment as well as AA concentrations were measured by mass spectrometry from blood samples drawn during a 5-h postprandial period. After HMP ingestion, [²H₅]phenylalanine was faster absorbed in the initial 2 h compared to STEAK and MINCED. The peak time in AA concentrations was faster in HMP compared to STEAK and MINCED. However, the peak AA concentrations were not different between STEAK, MINCED, and HMP. Although HMP showed to have the fastest initial amino acid appearance in older adults, the peak EAA concentrations were similar after ingesting meal with either STEAK, MINCED, or HMP in the 5-h postprandial period.

Nutritional interventions to improve muscle mass, muscle strength, and physical performance in older people: an umbrella review of systematic reviews and meta-analyses

CONTEXT

Sarcopenia is a progressive and generalized skeletal muscle disorder associated with an increased risk of adverse outcomes such as falls, disability, and death. The Belgian Society of Gerontology and Geriatrics has developed evidence-based guidelines for the prevention and treatment of sarcopenia. This umbrella review presents the results of the Working Group on Nutritional Interventions.

OBJECTIVE

The aim of this umbrella review was to provide an evidence-based overview of nutritional interventions targeting sarcopenia or at least 1 of the 3 sarcopenia criteria (ie, muscle mass, muscle strength, or physical performance) in persons aged ≥ 65 years.

DATA SOURCES

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, the PubMed and Web of Science databases were searched for systematic reviews and meta-analyses reporting the effect of nutritional supplementation on sarcopenia or muscle mass, strength, or physical performance.

DATA EXTRACTION

Two authors extracted data on the key characteristics of the reviews, including participants, treatment, and outcomes. Methodological quality of the reviews was assessed using the product A Measurement Tool to Assess Systematic Reviews. Three authors synthesized the extracted data and generated recommendations on the basis of an overall synthesis of the effects of each intervention. Quality of evidence was rated with the Grading of Recommendations Assessment, Development and Evaluation approach.

DATA ANALYSIS

A total of 15 systematic reviews were included. The following supplements were examined: proteins, essential amino acids, leucine, β-hydroxy-β-methylbutyrate, creatine, and multinutrient supplementation (with or without physical exercise). Because of both the low amount and the low to moderate quality of the reviews, the level of evidence supporting most recommendations was low to moderate.

CONCLUSIONS

Best evidence is available to recommend leucine, because it has a significant effect on muscle mass in elderly people with sarcopenia. Protein supplementation on top of resistance training is recommended to increase muscle mass and strength, in particular for obese persons and for ≥ 24 weeks. Effects on sarcopenia as a construct were not reported in the included reviews.

Energy, Macronutrients, Dietary Fibre and Salt Intakes in Older Adults in Ireland: Key Sources and Compliance with Recommendations

The global population is rapidly ageing. Adequate nutritional status can play a key role in preventing or delaying the progression of age-related diseases. The aim of this study was to estimate the usual intake of energy, macronutrients, dietary fibre and salt in order to determine compliance with recommendations and to identify the sources of these nutrients in older adults (≥65 years) in Ireland. This study is based on data from the cohort of older adults aged ≥65 years (n = 226) in the Irish National Adult Nutrition Survey (NANS) (2008-2010) which estimated food and nutrient intakes in a representative sample of adults 18-90 years using a 4 day weighed food record. This study found that while intakes of macronutrients are generally sufficient in this population group, older adults in Ireland have high intakes of total fat, saturated fat, sugar and salt and low intakes of dietary fibre. Future strategies to address the nutritional issues identified in older adults could include the promotion of healthy food choices together with improvements of the food supply including reformulation (fat, sugar and salt) to support successful ageing of our population.

Microbiota Stability and Gastrointestinal Tolerance in Response to a High-Protein Diet with and without a Prebiotic, Probiotic, and Synbiotic: A Randomized, Double-Blind, Placebo-Controlled Trial in Older Women

BACKGROUND

Higher protein intakes may help reduce sarcopenia and facilitate recovery from illness and injury in older adults. However, high-protein diets (HPDs) including animal-sourced foods may negatively perturb the microbiota, and provision of probiotics and prebiotics may mitigate these effects.

OBJECTIVE

The aim of this study was to examine the effects of HPD, with and without a probiotic and/or prebiotic, on gut microbiota and wellness in older women.

DESIGN

We conducted an 18-week, double-blind, placebo-controlled, crossover study.

PARTICIPANTS/SETTING

Participants were healthy, older women (mean age±standard deviation=73.7±5.6 years; n=26) recruited from Florida.

INTERVENTION

Participants received a weight-maintenance HPD for 2-week periods and the following, in random order: HPD alone (1.5 to 2.2 g/kg/day protein); HPD plus multistrain probiotic formulation (1.54×10⁹Bifidobacterium bifidum HA-132, 4.62×10⁹Bifidobacterium breve HA-129, 4.62×10⁹Bifidobacterium longum HA-135, 4.62×10⁹Lactobacillus acidophilus HA-122, and 4.62×10⁹Lactobacillus plantarum HA-119), HPD plus prebiotic (5.6 g inulin), and HPD plus synbiotic (probiotic plus inulin), separated by 2-week washouts. Stools were collected per period for quantitative polymerase chain reaction (strain recovery) and 16S ribosomal RNA gene amplicon sequencing analyses (microbiota profile). Measures of gastrointestinal and general wellness were assessed.

MAIN OUTCOME MEASURES

Microbiota composition and probiotic strain recovery were measured.

STATISTICAL ANALYSES

Microbiota composition was analyzed by Wilcoxon signed-rank test and t test. Secondary outcomes were analyzing using generalized linear mixed models.

RESULTS

The microbiota profile demonstrated relative stability with the HPD; representation of Lactobacillus, Lactococcus, and Streptococcus were enhanced, whereas butyrate producers, Roseburia and Anaerostipes, were suppressed. Lactococcus was suppressed with synbiotic vs other HPD periods. Recovery was confirmed for all probiotic strains. Indicators of wellness were unchanged, with the exception of a minimal increase in gastrointestinal distress with inulin. Fat-free mass increased from baseline to study end.

CONCLUSIONS

An HPD adhering to the recommended acceptable macronutrient distribution ranges maintains wellness in healthy older women and exerts minor perturbations to the microbiome profile, a group that may benefit from a higher protein intake. ClinicalTrials.gov ID: NCT #02445560.

Effect of Sit-to-Stand Exercises Combined With Protein-Rich Oral Supplementation in Older Persons: The Older Person's Exercise and Nutrition Study

OBJECTIVES

Nursing home (NH) residents are often undernourished and physically inactive, which contributes to sarcopenia and frailty. The Older Person's Exercise and Nutrition Study aimed to investigate the effects of sit-to-stand exercises (STS) integrated into daily care, combined with a protein-rich oral nutritional supplement (ONS), on physical function, nutritional status, body composition, health-related quality of life, and resource use.

DESIGN

Residents in 8 NHs were randomized by NH units into an intervention group (IG) or a control group (CG) (n = 60/group). The IG was a combination of STS (4 times/day) and ONS (2 bottles/day providing 600 kcal and 36 g protein) for 12 weeks.

SETTING AND PARTICIPANTS

The participants resided in NH units (dementia and somatic care), were ≥75 years of age, and able to rise from a seated position.

METHODS

The 30-second Chair Stand Test was the primary outcome. Secondary outcomes were balance, walking speed, dependence in activities of daily living, nutritional status and body composition, health-related quality of life, and resource use.

RESULTS

Altogether, 102 residents (age 86 ± 5 years, 62% female) completed the study. No improvement in the physical function assessments was observed in the IG, whereas body weight increased significantly (2.05 ± 3.5 kg, P = .013) vs the CG. Twenty-one (of 52) participants with high adherence to the intervention (ie, at least 40% compliance to the combined intervention) increased their fat free mass (2.12 kg (0.13, 4.26 interquartile range), P = .007 vs CG). Logistic regression analyses indicated that the odds ratio for maintained/improved 30-second Chair Stand Test was 3.5 (confidence interval 1.1, 10.9, P = .034) among the participants with high adherence compared with the CG.

CONCLUSIONS/IMPLICATIONS

Twelve-week intervention of daily STS combined with ONS in NH residents did not improve physical function, but increased body weight. Subgroup analyses indicated that high adherence to the combined intervention was associated with maintained or improved physical function and a gain of fat free mass.

A Perspective on the Transition to Plant-Based Diets: a Diet Change May Attenuate Climate Change, but Can It Also Attenuate Obesity and Chronic Disease Risk?

Current dietary guidelines advocate more plant-based, sustainable diets on the basis of scientific evidence about diet-health relations but also to address environmental concerns. Here, we critically review the effects of plant-based diets on the prevalence of obesity and other health outcomes. Plant-based diets per se have limited efficacy for the prevention and treatment of obesity, but most have beneficial effects in terms of chronic disease risk. However, with the considerable possibilities of translating plant-based diets into various types of dietary patterns, our analysis suggests that potential adverse health effects should also be considered in relation to vulnerable groups of the population. A transition to more plant-based diets may exert beneficial effects on the environment, but is unlikely to affect obesity, and may also have adverse health effects if this change is made without careful consideration of the nutritional needs of the individual relative to the adequacy of the dietary intake.

Dietary Protein and Amino Acids in Vegetarian Diets-A Review

While animal products are rich in protein, the adequacy of dietary protein intake from vegetarian/vegan diets has long been controversial. In this review, we examine the protein and amino acid intakes from vegetarian diets followed by adults in western countries and gather information in terms of adequacy for protein and amino acids requirements, using indirect and direct data to estimate nutritional status. We point out that protein-rich foods, such as traditional legumes, nuts and seeds, are sufficient to achieve full protein adequacy in adults consuming vegetarian/vegan diets, while the question of any amino acid deficiency has been substantially overstated. Our review addresses the adequacy in changes to protein patterns in people newly transitioning to vegetarian diets. We also specifically address this in older adults, where the issues linked to the protein adequacy of vegetarian diets are more complex. This contrasts with the situation in children where there are no specific concerns regarding protein adequacy because of their very high energy requirements compared to those of protein. Given the growing shifts in recommendations from nutrition health professionals for people to transition to more plant-based, whole-food diets, additional scientific evidence-based communications confirming the protein adequacy of vegetarian and vegan diets is warranted.

Dietary strategies for mitigating osteosarcopenia in older adults: a narrative review

The synchronic loss of bone mineral density and decrease in muscle mass, strength, and function defines the scenario of osteosarcopenia, which is associated with an increased risk of falls and fractures in older adults. An important role in preventing muscle and bone loss is played by nutritional factors, in particular the intake of proteins, calcium, magnesium and vitamin D. This review summarizes the available literature concerning the influence of protein intake and supplementation (vitamin D, Ca, Mg, branched-chain amino acids) on the decline of musculoskeletal integrity in healthy older adults. Furthermore, in this paper, we attempted to give some suggestions to build up adequate nutritional and dietary strategies against the age-related loss of muscle and bone mass.

Investigating Risk of Suboptimal Macro and Micronutrient Intake and Their Determinants in Older Danish Adults with Specific Focus on Protein Intake-A Cross-Sectional Study

Suboptimal intake of nutrients is associated with adverse health outcomes. The current study investigated the risk of suboptimal macro and micronutrient intake and their potential determinants in a cross-sectional study of community-dwelling older Danish adults (65⁻81 years). Nutrient intake was obtained through a 3-day weighted dietary record and information on personal characteristics and attitudes towards specific foods and dietary habits and nutrition through questionnaires. Dietary Reference Values (DRV) from the Nordic Nutrition Recommendations were used for the assessment. Among 157 participants, 68% and 66% had risk of suboptimal intake of dietary fiber and saturated fatty acids (SFA). For mono-unsaturated fatty acids (MUFA) and poly-unsaturated fatty acids (PUFA), the numbers were 47% and 62%, respectively. Increased risk of suboptimal protein intake was estimated in 3 to 45% of the participants, depending on the criteria used for the DRV and of the mode of expressing protein intake. Fifty percent had intakes of alcohol above the maximum recommended intake. Risk of micronutrient inadequacy was particularly high for vitamin D and thiamine (80 and 45%, respectively). Total energy intake and attitude regarding healthy eating were associated with lower nutrient intake. The current study illustrates that there is room for improvements in the dietary quality of community dwelling older Danish adults.

Nutrition from a climate change perspective

Climate change is threatening future global food and nutrition security. Limiting the increase in global temperature to 1·5 °C set out in The Paris Agreement (2015) while achieving nutrient security means overhauling the current food system to create one that can deliver healthy and sustainable diets. To attain this, it is critical to understand the implications for nutrition of actions to mitigate climate change as well as the impacts of climate change on food production and the nutrient composition of foods. It is widely recognised that livestock production has a much greater environmental burden than crop production, and therefore advice is to reduce meat consumption. This has triggered concern in some sectors about a lack of protein in diets, which hence is driving efforts to find protein replacements. However, in most high- and middle-income countries, protein intakes far exceed dietary requirements and it would even if all meat were removed from diets. Reduction in micronutrients should be given more attention when reducing meat. Simply eating less meat does not guarantee healthier or more sustainable diets. Climate change will also affect the type, amount and nutrient quality of food that can be produced. Studies have shown that increased temperature and elevated CO2 levels can reduce the nutrient density of some staple crops, which is of particular concern in low-income countries. Nutrition from a climate change perspective means considering the potential consequences of any climate action on food and nutrition security. In this paper, we discuss these issues from an interdisciplinary perspective.

Prevalence and determinants of low protein intake in very old adults: insights from the Newcastle 85+ Study

PURPOSE

The very old (aged ≥ 85 years), fastest growing age group in most western societies, are at especially high risk of muscle mass and strength loss. The amount, sources and timing of protein intake may play important roles in the aetiology and management of sarcopenia. This study investigated the prevalence and determinants of low protein intake in 722 very old adults participating in the Newcastle 85+ Study.

METHODS

Protein intake was estimated with 2 × 24-h multiple pass recalls (24 h-MPR) and contribution (%) of food groups to protein intake was calculated. Low protein intake was defined as intake < 0.8 g of protein per adjusted body weight per day. A backward stepwise multivariate linear regression model was used to explore socioeconomic, health and lifestyle predictors of protein intake.

RESULTS

Twenty-eight percent (n = 199) of the community-living very old in the Newcastle 85+ Study had low protein intake. Low protein intake was less likely when participants had a higher percent contribution of meat and meat products to total protein intake (OR 0.97, 95% CI 0.95, 1.00) but more likely with a higher percent contribution of cereal and cereal products and non-alcoholic beverages. Morning eating occasions contributed more to total protein intake in the low than in the adequate protein intake group (p < 0.001). Being a woman (p < 0.001), having higher energy intake (p < 0.001) and higher tooth count (p = 0.047) was associated with higher protein intake in adjusted models.

CONCLUSION

This study provides novel evidence on the prevalence of low protein intake, diurnal protein intake patterns and food group contributors to protein intake in the very old.

Markers of Renal Function in Older Adults Completing a Higher Protein Obesity Intervention and One Year Later: Findings from the MEASUR-UP Trial

Increases in rates of obesity in the older population are hastening the development of chronic illnesses, including chronic kidney disease (CKD). However, obesity reduction in older adults is besought with concerns about the long-term benefit/risk, especially regarding loss of muscle mass and its impact on function. Higher protein intakes have been advocated to help offset the tendency for loss of muscle during weight reduction but this raises concerns about possible negative effects on older kidneys. We assessed markers of renal function in venous blood samples collected during a six-month randomized controlled weight loss trial of higher protein intake in obese (n = 67; BMI ≥ 30 kg/m²) older (≥60 years) adults with physical frailty and age-normal renal status (glomerular filtration rate [GFR] ≥ 45); the Control diet (0.8 g protein/kg body weight/day; n = 21) was compared to a protein-enhanced (1.2 g/g protein/kg body weight/day with 30 g protein/meal; n = 41; Protein) diet. Results showed no group effect of the Protein treatment on markers of renal function (estimated GFR, blood urea nitrogen, and creatinine), either upon intervention completion or one year later. Our findings align with literature support for the benefits of higher protein in the diets of older individuals during obesity reduction and help to confirm the safety of moderate increases in protein intake during weight loss in this population.

A study protocol of Older Person's Exercise and Nutrition Study (OPEN) - a sit-to-stand activity combined with oral protein supplement - effects on physical function and independence: a cluster randomized clinical trial

BACKGROUND

Poor nutrition and age per see add to the development of sarcopenia, i.e. loss of muscle mass and strength, which contributes to increased risk of impaired activities of daily living (ADL) and reduced independence. Protein deficiency plays an important role in the development of sarcopenia. In order to increase the muscle mass protein intake should be combined with physical exercise. A daily physical activity, the sit-to-stand exercise, has been proven to decrease older persons' dependence in ADL. Our study aims to evaluate the effects of the sit-to-stand exercise in combination with a protein-rich nutritional supplement, on physical function and independence in frail nursing home residents. The resident's perceptions and experiences of the intervention and the staff's experiences of supporting the resident to complete the intervention will also be explored.

METHODS

The study is a two-arm cluster-randomized controlled trial which will be performed in nursing homes at two municipalities in Sweden. We will recruit 120 residents, age 75 or older and able to stand up from a seated position. Residents (n = 60) randomized to the intervention group will perform the sit-to-stand exercise at four occasions daily and will be offered a protein-rich oral supplement, twice a day. The intervention period will last for 12 weeks and measures of physical function, nutritional status, quality of life and health economy will be performed at baseline and at 12-weeks follow-up. The primary outcome will be the number of chair rises performed in 30 s. The control group will receive standard care. Data will be analysed by intention-to-treat analysis and with mixed effect models. During the last part of the intervention period individual interviews with the residents, on the topic of feasibility with the OPEN concept will be held. Likewise, focus-group-interviews with staff will be performed.

DISCUSSION

The residents' physical and mental health could be expected to improve. Even the work situation for staff could be positively affected. One innovative feature of the OPEN study is the simple intervention consisting of a basic daily activity that can be performed by several nursing home residents with the support of existing staff and available resources.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02702037.

Does Protein Intake Affect Metabolic Risk Factors among Older Adults in Korea?

Background

Carbohydrate intake can impact metabolic risk factors, but related research on protein intake in the elderly is rare. Our purpose was to estimate protein intake and explore how different levels of protein intake influence metabolic risk factors in Korean older adults.

Methods

Data were obtained from men aged 51-70 years (n=1,735), men aged ≥71 years (n=700), women aged 51-70 years (n=2,305), and women aged ≥71 years (n=957). Health and dietary data were obtained from the Korean National Health and Nutrition Examination Survey of 2010-2011.

Results

Relative to the recommended protein intake based on the Dietary Reference Intakes for Koreans, inadequate intake was higher in women and super-aging groups than in others. Women had an increased risk of having metabolic risk factors. After adjustment for age and sex, compared with those in the highest quartile of protein intake levels (>1.2 g protein/kg body weight/day), participants in the lowest quartile (<0.8 g protein/kg body weight/day) had increased odds ratios (ORs) for abdominal obesity (men: OR, 2.67; 95% confidence interval [CI], 2.00-3.56; women: OR, 3.42; 95% CI, 2.64-4.43), hypertriglyceridemia (men: OR, 1.44; 95% CI, 1.08-1.93; women: OR, 1.82; 95% CI, 1.45-2.29), and high fasting blood glucose (men: OR, 1.41; 95% CI, 1.07-1.87; women: OR, 2.03; 95% CI, 1.48-2.79).

Conclusion

Protein intake (<0.8 g protein/kg body weight/day) lower than the recommend level was associated with a higher risk of metabolic abnormalities in Korean older adults. In particular, lower intake of protein contributed to a higher prevalence of metabolic risk factors in women than in men.

Mitigating Nutrition and Health Deficiencies in Older Adults: A Role for Food Innovation?

The aim of this review is to describe the factors contributing to diminished food intake, resulting in nutritional deficiencies and associated health conditions in older adults and proposes food innovation strategies to mitigate these. Research has provided convincing evidence of a link between healthy eating patterns and healthy aging. There is a need to target new food product development (NPD) with functional health benefits specifically designed to address the particular food-related needs of older consumers. When developing foods for older adults, consideration should be given to the increased requirements for specific macro- and micronutrients, especially protein, calcium, vitamin D, and vitamin B. Changes in chemosensory acuity, chewing difficulties, and reduced or poor swallowing ability should also be considered. To compensate for the diminished appetite and reduced intake, foods should be energy dense, nutritionally adequate, and, most importantly, palatable, when targeting this cohort. This paper describes the potential of new food product development to facilitate dietary modification and address health deficiencies in older adults.

Balanço de macronutrientes na dieta de idosos brasileiros: análises da Pesquisa Nacional de Alimentação 2008-2009

RESUMO: Objetivo: Analisar a contribuição de proteína, lipídio e carboidrato no total de energia da dieta de idosos das diferentes regiões brasileiras. Métodos: Foram analisados dados de 4.286 idosos (60 a 104 anos) provenientes da Pesquisa de Orçamentos Familiares 2008/2009. Baseado no consumo obtido por dois registros alimentares, o programa Multiple Source Method estimou o consumo habitual de macronutrientes e gordura saturada. As recomendações do Institute of Medicine (IOM), segundo os Acceptable Macronutrient Distribution Ranges (AMDR), foram utilizadas para avaliar a participação relativa dos macronutrientes de acordo com percentual energético (PE). Modelos de regressão linear identificaram diferenças entre PE dos macronutrientes, situação do domicílio, macrorregiões e gênero. Resultados: A proteína foi o macronutriente que apresentou maior concordância com o AMDR (99,8%). Com relação ao PE lipídico, observou-se que 9,2% da população ficaram acima da recomendação, sendo o dobro do encontrado para carboidrato (4,9%) e nove vezes o percentual de idosos, cujo PE-proteico (1,0%) foi acima do recomendado. Em 14,5% dos idosos a ingestão de carboidratos foi abaixo da AMDR, sendo que essas dietas apresentaram maior PE lipídico (β = 8,19; p < 0,001), revelando que 50% dos idosos que consumiam carboidratos abaixo do PE recomendado apresentou um consumo excessivo de lipídio. Segundo macrorregiões, o Centro-Oeste foi o único a apresentar diferença para carboidrato, sendo esta de menor percentual (51,6%; p < 0,05). A região Sul (17,9%; p < 0,01) apresentou o menor PE proteico e o maior de lipídios (28,7%; p < 0,01). Conclusões: A elevada frequência de inadequação da ingestão de lipídio pode significar uma pior qualidade da dieta, contribuindo com o aumento no risco de desenvolvimento de doenças crônicas.

Counteracting Age-related Loss of Skeletal Muscle Mass: a clinical and ethnological trial on the role of protein supplementation and training load (CALM Intervention Study): study protocol for a randomized controlled trial

Background

Aging is associated with decreased muscle mass and functional capacity, which in turn decrease quality of life. The number of citizens over the age of 65 years in the Western world will increase by 50 % over the next four decades, and this demographic shift brings forth new challenges at both societal and individual levels. Only a few longitudinal studies have been reported, but whey protein supplementation seems to improve muscle mass and function, and its combination with heavy strength training appears even more effective. However, heavy resistance training may reduce adherence to training, thereby attenuating the overall benefits of training. We hypothesize that light load resistance training is more efficient when both adherence and physical improvement are considered longitudinally. We launched the interdisciplinary project on Counteracting Age-related Loss of Skeletal Muscle Mass (CALM) to investigate the impact of lifestyle changes on physical and functional outcomes as well as everyday practices and habits in a qualitative context.

Methods

We will randomize 205 participants older than 65 years to be given 1 year of two daily nutrient supplements with 10 g of sucrose and 20 g of either collagen protein, carbohydrates, or whey. Further, two groups will perform either heavy progressive resistance training or light load training on top of the whey supplement.

Discussion

The primary outcome of the CALM Intervention Study is the change in thigh cross-sectional area. Moreover, we will evaluate changes in physical performance, muscle fiber type and acute anabolic response to whey protein ingestion, sensory adaptation, gut microbiome, and a range of other measures, combined with questionnaires on life quality and qualitative interviews with selected subjects. The CALM Intervention Study will generate scientific evidence and recommendations to counteract age-related loss of skeletal muscle mass in elderly individuals.

Trial registration

ClinicalTrials.gov NCT02034760. Registered on 10 January 2014.

ClinicalTrials.gov NCT02115698. Registered on 14 April 2014.

Danish regional committee of the Capital Region H-4-2013-070. Registered on 4 July 2013.

Danish Data Protection Agency 2012-58-0004 – BBH-2015-001 I-Suite 03432. Registered on 9 January 2015.

Considering the benefits of egg consumption for older people at risk of sarcopenia

Sarcopenia is an important health issue for older people. It is closely linked with frailty and malnutrition and can significantly reduce both health and quality of life for those affected. Sarcopenic decline in muscle mass can start as early as the fourth and fifth decade of life, so the maintenance of muscle mass throughout adulthood, through regular physical activity and a balanced diet, should be an important consideration in reducing the risk of sarcopenia in older age. Maintaining regular exercise throughout older age remains key to the treatment of sarcopenia, as does an adequate intake of nutrients, including high-quality protein and vitamin D. A significant proportion of older people fail to meet the recommended requirements for protein; it has also been suggested that the requirements in existing recommendations could be higher. Evidence is emerging that an adequate intake of protein at each meal may be required to optimise muscle synthesis in older people. Eggs are an inexpensive, widely available and easily digestible source of high-quality protein and contain a significant proportion of leucine, an amino acid that is important for muscle synthesis, as well as many other nutrients of significance for older people, including vitamin D and omega-3 fatty acids. For many older people, eggs are a familiar and acceptable protein food at breakfast and other meals. Encouraging both those approaching older age and older people to include eggs more frequently, as part of a healthy, balanced diet and in addition to physical activity, could help them maintain their muscle strength and function, thereby preserving their functional capacity and reducing morbidity, mortality and healthcare costs associated with sarcopenia.

Protein intakes and their nutritional sources during the first 2 years of life: secondary data evaluation from the European Childhood Obesity Project

BACKGROUND/OBJECTIVES

High protein intake in infancy affects future obesity risk and other health outcomes. We aim to describe total protein intake and its sources in a birth cohort in five European countries over the first 2 years of life.

SUBJECTS/METHODS

A total of 746 formula-fed infants were included. Three-day weighed dietary records at 6, 7, 8, 9, 12, 18 and 24 months of age were used. Kruskal-Wallis, ANOVA and Friedman's tests were used to assess possible differences in nutritional intake among countries and over time.

RESULTS

Dairy products were the main components of the infants' diets. Cow's milk was rarely introduced before 12 months of age, whereas infants' formula was the main contributor of protein intake. Food choices and protein intake differed among countries (P<0.001). Protein intake often exceeded European recommendations from 9 months onwards, partly because of the substitution of dairy protein (mainly infant formula) by meat protein. Two nutritional patterns were identified that were characterised by differences in energy, fat, protein and animal protein intake. Finally, food consumption was not always in line with protein intakes, and thus infants from some countries showed high consumption of specific food groups but relatively low protein intakes.

CONCLUSIONS

During weaning, over-limited substitution of dairy products with other sources (especially meat) resulted in relatively high protein intakes in formula-fed infants. Differences in preferences of specific protein sources from complementary foods existed among European countries. Great opportunities in improving early nutrition were revealed, although cultural and geographical differences should always be considered.

Medium-Chain Triglycerides in Combination with Leucine and Vitamin D Increase Muscle Strength and Function in Frail Elderly Adults in a Randomized Controlled Trial

BACKGROUND

Sarcopenia, the loss of skeletal muscle mass, strength, and function, is common in elderly individuals but difficult to treat.

OBJECTIVE

A combination of nutrients was investigated to treat sarcopenia in very frail elderly adults.

METHODS

We enrolled 38 elderly nursing home residents (11 men and 27 women with a mean ± SD age of 86.6 ± 4.8 y) in a 3-mo randomized, controlled, single-blind, parallel group trial. The participants were randomly allocated to 3 groups. The first group received a daily l-leucine (1.2 g) and cholecalciferol (20 μg)-enriched supplement with 6 g medium-chain triglycerides (TGs) (MCTs) (LD + MCT); the second group received the same leucine and cholecalciferol-enriched supplement with 6 g long-chain TGs (LD + LCT); and the third group did not receive any supplements (control). The supplement and oils were taken at dinner, and changes in muscle mass, strength, and function were monitored.

RESULTS

The increase in body weight in the LD + MCT (1.1 ± 1.0 kg) and LD + LCT (0.8 ± 1.1 kg) groups was greater than that in the control group (-0.5 ± 0.9 kg) (P < 0.05). After 3 mo, participants in the LD + MCT group had a 13.1% increase in right-hand grip strength (1.2 ± 1.0 kg, P < 0.01), a 12.5% increase in walking speed (0.078 ± 0.080 m/s, P < 0.05), a 68.2% increase in a 10-s leg open-and-close test performance (2.31 ± 1.68 n/10 s, P < 0.001), and a 28.2% increase in peak expiratory flow (53 ± 59 L/min, P < 0.01). No significant improvements in muscle mass, strength, or function were observed in the LD + LCT or control groups.

CONCLUSION

The combined supplementation of MCTs (6 g), leucine-rich amino acids, and cholecalciferol at dinner may improve muscle strength and function in frail elderly individuals. This trial was registered at the University Hospital Medical Information Network Clinical Trials Registry as UMIN000017567.

Glutamine metabolism in advanced age

Glutamine, reviewed extensively in the last century, is a key substrate for the splanchnic bed in the whole body and is a nutrient of particular interest in gastrointestinal research. A marked decrease in the plasma glutamine concentration has recently been observed in neonates and adults during acute illness and stress. Although some studies in newborns have shown parenteral and enteral supplementation with glutamine to be of benefit (by decreasing proteolysis and activating the immune system), clinical trials have not demonstrated prolonged advantages such as reductions in mortality or risk of infections in adults. In addition, glutamine is not able to combat the muscle wasting associated with disease or age-related sarcopenia. Oral glutamine supplementation initiated before advanced age in rats increases gut mass and improves the villus height of mucosa, thereby preventing the gut atrophy encountered in advanced age. Enterocytes from very old rats continuously metabolize glutamine into citrulline, which allowed, for the first time, the use of citrulline as a noninvasive marker of intestinal atrophy induced by advanced age.

Effects on Weight, Blood Lipids, Serum Fatty Acid Profile and Coagulation by an Energy-Dense Formula to Older Care Residents: A Randomized Controlled Crossover Trial

OBJECTIVES

Dietary intake in frail old adults is often lower than estimated needs. The aim of this study was to evaluate the effects of an energy-dense oral supplement on nutritional status, food intake, and physical function in residents living in care residential homes.

DESIGN

Randomized controlled intervention trial with a crossover design.

SETTING

Five care residential homes in the southern Stockholm area.

PARTICIPANTS

Older people living at care residential homes: age 65 or older, malnourished or at risk of malnutrition according to Mini Nutritional Assessment-Short Form (MNA-SF).

INTERVENTION

Energy-dense formula (oleic and linoleic acid emulsion enriched with protein and micronutrients) (Calogen Extra, Nutricia) 30 mL distributed 3 times daily for 6 weeks.

MEASUREMENTS

Body weight, 3-day food and fluid record, appetite rating, and physical function (ie, Short Physical Performance Battery, grip strength, and peak expiratory flow). Biochemical indicators of nutritional status, blood lipids, and serum phospholipid fatty acid (FA) profile.

RESULTS

Twenty-eight participants completed the 2 phases of the crossover study; group A (n = 14, 87 ± 6 years, 50% women) and group B (n = 14, 82 ± 8 years, 71% women). The intervention periods combined resulted in significantly (P < .05) increased energy intake (238 ± 544 kcal), weight gain (1.4 ± 3.7 kg), improved appetite, relative reduction of saturated FA and increase in polyunsaturated FA, increased apoliporotein A, and reduced serum fibrinogen (-0.9 ± 1.5 g/L).

CONCLUSION

Distribution of an oleic and linoleic acid based fat emulsion enriched with protein and micronutrients (Calogen Extra) 3 times daily to old people in care residential homes improved nutritional status, had positive effects on fatty acid profile and blood lipids, and a potential antithrombotic effect. CLINICALTRIALS.

GOV IDENTIFIER

NCT01259999.

The effect of glutamine intake on complications of colorectal and colon cancer treatment: A systematic review

Background:

Improvement in complications of antitumor agents and surgery is important to enhance life quality and survival among patients with colon and colorectal cancer. It has been reported that some dietary components such as glutamine (Gln) have beneficial effects on these complications of cancer therapies. However, the results of studies are inconsistent in this area. We performed a review on randomized controlled trials (RCTs) evaluating the effects of Gln intake on complications related to therapeutic strategies of the colon and colorectal cancer.

Materials and Methods:

A systematic search was conducted in PubMed, Google Scholar, Cochrane Library, and SID databases to find the relevant literature, published before July 2015.

Results:

Nine RCTs of 217 screened articles were included in this systematic review. The results of the present review suggested that Gln intake among colon and colorectal cancer patients could reduce some complications induced by chemotherapy such as gut mucositis and diarrhea and improve nitrogen balance, immune system and wound healing after surgery, whereas benefits role of Gln on radiochemotherapy side effects were not provided.

Conclusion:

The role of Gln intake on some improvement of complications induced by cancer therapeutic methods and shorten the length of hospital stay may be promising and one that is worthy of further exploration.

Association of protein intake with the change of lean mass among elderly women: The Osteoporosis Risk Factor and Prevention - Fracture Prevention Study (OSTPRE-FPS)

Low protein intake can lead to declined lean mass (LM) in elderly. We examined the associations of total protein (TP), animal protein (AP) and plant protein (PP) intakes with LM. The association of TP intake with LM change was further evaluated according to weight change status. This cross-sectional and prospective cohort study included 554 women aged 68 (sd 1·9) years from the Osteoporosis Risk Factor and Prevention – Fracture Prevention Study (OSTPRE-FPS). The intervention group (n 270) received daily cholecalciferol (800 IU; 20 μg) and Ca (1000 mg) for 3 years while the control group received neither supplementation nor placebo (n 282). Participants filled out a questionnaire on lifestyle factors and a 3-d food record in 2002 and underwent dual-energy X-ray absorptiometry for body composition measurements at baseline and 3 years. Multiple linear regressions evaluated the association between protein intake and LM, adjusting for relevant covariates. At the baseline TP and AP intakes were positively associated with LM and trunk LM, TP was associated also with appendicular LM (aLM). Follow-up results showed that in the total population and the intervention group, higher TP and AP were associated with increased LM and aLM (P ≤ 0·050). No such associations were observed in the control group. PP intake was also associated with aLM change in the total population. Overall, the associations were independent of fat mass. Further, among weight maintainers, TP intake was positively associated with LM, aLM and trunk LM changes (P ≤ 0·020). In conclusion, dietary TP, especially AP, intake may be a modifiable risk factor for sarcopenia by preserving LM in the elderly.

Nutrition and physical activity for the prevention and treatment of age-related sarcopenia

Sarcopenia, defined as loss of skeletal muscle mass and function, is associated with adverse outcomes such as physical disability, impaired quality of life and increased mortality. Several mechanisms are involved in the development of sarcopenia. Potentially modifiable factors include nutrition and physical activity. Protein metabolism is central to the nutritional issues, along with other potentially modifying nutritional factors as energy balance and vitamin D status. An increasing but still incomplete knowledge base has generated recent recommendations on an increased protein intake in the elderly. Several factors beyond the total amount of protein consumed emerge as potentially important in this context. A recent summit examined three hypotheses: (1) A meal threshold; habitually consuming 25-30 g protein at breakfast, lunch and dinner provides sufficient protein to effectively stimulate muscle protein anabolism; (2) Protein quality; including high-quality protein at each meal improves postprandial muscle protein synthesis; and (3) performing physical activity in close temporal proximity to a high-quality protein meal enhances muscle anabolism. Optimising the potential for muscle protein anabolism by consuming an adequate amount of high-quality protein at each meal, in combination with physical activity, appears as a promising strategy to prevent or delay the onset of sarcopenia. However, results of interventions are inconsistent, and well-designed, standardised studies evaluating exercise or nutrition interventions are needed before guidelines can be developed for the prevention and treatment of age-related sarcopenia.

Sarcopenic obesity and complex interventions with nutrition and exercise in community-dwelling older persons--a narrative review

One of the many threats to independent life is the age-related loss of muscle mass and muscle function commonly referred to as sarcopenia. Another important health risk in old age leading to functional decline is obesity. Obesity prevalence in older persons is increasing, and like sarcopenia, severe obesity has been consistently associated with several negative health outcomes, disabilities, falls, and mobility limitations. Both sarcopenia and obesity pose a health risk for older persons per se, but in combination, they synergistically increase the risk for negative health outcomes and an earlier onset of disability. This combination of sarcopenia and obesity is commonly referred to as sarcopenic obesity. The present narrative review reports the current knowledge on the effects of complex interventions containing nutrition and exercise interventions in community-dwelling older persons with sarcopenic obesity. To date, several complex interventions with different outcomes have been conducted and have shown promise in counteracting either sarcopenia or obesity, but only a few studies have addressed the complex syndrome of sarcopenic obesity. Strong evidence exists on exercise interventions in sarcopenia, especially on strength training, and for obese older persons, strength exercise in combination with a dietary weight loss intervention demonstrated positive effects on muscle function and body fat. The differences in study protocols and target populations make it impossible at the moment to extract data for a meta-analysis or give state-of-the-art recommendations based on reliable evidence. A conclusion that can be drawn from this narrative review is that more exercise programs containing strength and aerobic exercise in combination with dietary interventions including a supervised weight loss program and/or protein supplements should be conducted in order to investigate possible positive effects on sarcopenic obesity.

Understanding the gastrointestinal tract of the elderly to develop dietary solutions that prevent malnutrition

Although the prevalence of malnutrition in the old age is increasing worldwide a synthetic understanding of the impact of aging on the intake, digestion, and absorption of nutrients is still lacking. This review article aims at filling the gap in knowledge between the functional decline of the aging gastrointestinal tract (GIT) and the consequences of malnutrition on the health status of elderly. Changes in the aging GIT include the mechanical disintegration of food, gastrointestinal motor function, food transit, chemical food digestion, and functionality of the intestinal wall. These alterations progressively decrease the ability of the GIT to provide the aging organism with adequate levels of nutrients, what contributes to the development of malnutrition. Malnutrition, in turn, increases the risks for the development of a range of pathologies associated with most organ systems, in particular the nervous-, muscoskeletal-, cardiovascular-, immune-, and skin systems. In addition to psychological, economics, and societal factors, dietary solutions preventing malnutrition should thus propose dietary guidelines and food products that integrate knowledge on the functionality of the aging GIT and the nutritional status of the elderly. Achieving this goal will request the identification, validation, and correlative analysis of biomarkers of food intake, nutrient bioavailability, and malnutrition.

Dietary intake in the dependent elderly: evaluation of the risk of nutritional deficit

BACKGROUND

Malnutrition is a frequent problem in elderly dependent patients and their prognosis is adversely affected. Assessment of food consumption and adequacy of energy and nutrient intake of dependent elderly is needed to plan any selected actions for this population.

METHODS

The study comprised a multicentre cross-sectional study of 190 users (≥65 years) of a home care programme provided by primary care centers in Tarragona (Spain), at nutritional risk (Mini Nutritional Assessment: 17-23.5 points). Food consumption was assessed using a semiquantitative validated food frequency questionnaire. Energy intake was compared with the Spanish dietary reference intake (DRI) and nutritional intakes with the DRI of the American Institute of Medicine.

RESULTS

Mean (SD) age was 85.0 (7.2) years (67.5% female). The food items consumed were varied but lower than the recommended portions for cereals, fruits, vegetables and legumes. Energy intake was 7454.2 (1553.9 kJ day(-1)) [1781.6 (371.4) kcal day(-1)] (97.7% of recommended dietary allowance; RDA) and protein intake was 1.0 (0.4) g kg(-1) of weight (121.4% of RDA). Proteins provided 13.3%, carbohydrates provided 39.9% and fats provided 45.8% of energy intake. The intakes of calcium, vitamin D, vitamin E and folates were less than two-thirds of the RDA and their probability of inadequate intake was >85%.

CONCLUSIONS

Dietary intakes of elderly dependent patients at nutritional risk were well balanced. In general, energy and protein intakes meet the recommendations. The diet was high in energy density, low in complex carbohydrates, high in simple carbohydrates and excessive in fats. The dependent elderly had inadequate intake of micronutrients often related to fragility, such as calcium, vitamin D, vitamin E and folates.

Nutrigerontology: why we need a new scientific discipline to develop diets and guidelines to reduce the risk of aging-related diseases

Many diets and nutritional advice are circulating, often based on short- or medium-term clinical trials and primary outcomes, like changes in LDL cholesterol or weight. It remains difficult to assess which dietary interventions can be effective in the long term to reduce the risk of aging-related disease and increase the (healthy) lifespan. At the same time, the scientific discipline that studies the aging process has identified some important nutrient-sensing pathways that modulate the aging process, such as the mTOR and the insulin/insulin-like growth factor signaling pathway. A thorough understanding of the aging process can help assessing the efficacy of dietary interventions aimed at reducing the risk of aging-related diseases. To come to these insights, a synthesis of biogerontological, nutritional, and medical knowledge is needed, which can be framed in a new discipline called 'nutrigerontology'.

Protein intake and exercise for optimal muscle function with aging: recommendations from the ESPEN Expert Group

The aging process is associated with gradual and progressive loss of muscle mass along with lowered strength and physical endurance. This condition, sarcopenia, has been widely observed with aging in sedentary adults. Regular aerobic and resistance exercise programs have been shown to counteract most aspects of sarcopenia. In addition, good nutrition, especially adequate protein and energy intake, can help limit and treat age-related declines in muscle mass, strength, and functional abilities. Protein nutrition in combination with exercise is considered optimal for maintaining muscle function. With the goal of providing recommendations for health care professionals to help older adults sustain muscle strength and function into older age, the European Society for Clinical Nutrition and Metabolism (ESPEN) hosted a Workshop on Protein Requirements in the Elderly, held in Dubrovnik on November 24 and 25, 2013. Based on the evidence presented and discussed, the following recommendations are made (a) for healthy older people, the diet should provide at least 1.0-1.2 g protein/kg body weight/day, (b) for older people who are malnourished or at risk of malnutrition because they have acute or chronic illness, the diet should provide 1.2-1.5 g protein/kg body weight/day, with even higher intake for individuals with severe illness or injury, and (c) daily physical activity or exercise (resistance training, aerobic exercise) should be undertaken by all older people, for as long as possible.