Optimal protein intake in the elderly

Protein intake distribution pattern does not affect anabolic response, lean body mass, muscle strength or function over 8 weeks in older adults: A randomized-controlled trial

BACKGROUND & AIMS

In our recent acute metabolic study, we found no differences in the anabolic response to differing patterns of dietary protein intake. To confirm this in a chronic study, we investigated the effects of protein distribution pattern on functional outcomes and protein kinetics in older adults over 8 weeks.

METHODS

To determine chronic effects of protein intake pattern at 1.1 g protein/kg/day in mixed meals on lean body mass (LBM), functional outcomes, whole body protein kinetics and muscle protein fractional synthesis rate (MPS) over 8-week respective dietary intervention, fourteen older subjects were randomly divided into either EVEN or UNVEN group. The UNEVEN group (n = 7) consumed the majority of dietary protein with dinner (UNEVEN, 15/20/65%; breakfast, lunch, dinner), while the EVEN group (n = 7) consumed dietary protein evenly throughout the day (EVEN: 33/33/33%).

RESULTS

We found no significant differences in LBM, muscle strength, and other functional outcomes between EVEN and UNEVEN before and after 8-week intervention. Consistent with these functional outcomes, we did not find significant differences in the 20-h integrated whole body protein kinetics [net protein balance (NB), protein synthesis (PS), and breakdown (PB)] above basal states and MPS between EVEN and UNEVEN intake patterns.

CONCLUSIONS

We conclude that over an 8-week intervention period, the protein intake distribution pattern in mixed meals does not play an important role in determining anabolic response, muscle strength, or functional outcomes. This trial is registered at https://ClinicalTrials.gov as NCT02787889.

Effect of a high protein diet and/or resistance exercise on the preservation of fat free mass during weight loss in overweight and obese older adults: a randomized controlled trial

BACKGROUND

Intentional weight loss in obese older adults is a risk factor for accelerated muscle mass loss. We investigated whether a high protein diet and/or resistance exercise preserves fat free mass (FFM) during weight loss in overweight and obese older adults.

METHODS

We included 100 overweight and obese adults (55-80 year) in a randomized controlled trial (RCT) with a 2 × 2 factorial design and intention-to-treat analysis. During a 10-week weight loss program all subjects followed a hypocaloric diet. Subjects were randomly allocated to either a high protein (1.3 g/kg body weight) or normal protein diet (0.8 g/kg), with or without a resistance exercise program 3 times/week. FFM was assessed by air displacement plethysmography.

RESULTS

At baseline, mean (±SD) BMI was 32 ± 4 kg/m². During intervention, protein intake was 1.13 ± 0.35 g/kg in the high protein groups vs. 0.98 ± 0.29 in the normal protein groups, which reflects a 16.3 ± 5.2 g/d higher protein intake in the high protein groups. Both high protein diet and exercise did not significantly affect change in body weight, FFM and fat mass (FM). No significant protein*exercise interaction effect was observed for FFM. However, within-group analysis showed that high protein in combination with exercise significantly increased FFM (+0.6 ± 1.3 kg, p = 0.011).

CONCLUSION

A high protein diet, though lower than targeted, did not significantly affect changes in FFM during modest weight loss in older overweight and obese adults. There was no significant interaction between the high protein diet and resistance exercise for change in FFM. However, only the group with the combined intervention of high protein diet and resistance exercise significantly increased in FFM.

TRIAL REGISTRATION

Dutch Trial Register, number NTR4556, date 05-01-2014.

Nutrition Support for Persistent Inflammation, Immunosuppression, and Catabolism Syndrome

Despite tremendous advances in critical care, multiple-organ failure continues to be a significant problem. However, in recent years, far fewer patients with multiple-organ failure die early, but many experience ongoing immune dysregulation and are developing persistent inflammation, immunosuppression, and catabolism syndrome (PICS). Most PICS patients are discharged to nonhome destinations, fail to rehabilitate, and succumb to indolent death. From a nutrition perspective, patients with PICS experience persistent inflammation-induced cachexia despite evidenced-based recommended intensive care unit nutrition support. Recent basic and translational research indicates that prolonged expansion of myeloid-derived suppressor cells plays a central role in the pathogenesis of PICS. Myeloid-derived suppressor cells express arginase 1, which depletes arginine, causing immunosuppression and impaired wound healing. This is the rationale for arginine supplementation in PICS. Other nutrition support recommendations for PICS are based on inferences made from other patient populations who experience similar persistent inflammation-induced cachexia. These include patients with established cancers, major burns, and sarcopenia. These patients experience anabolic resistance, but studies show that this can be overcome by providing higher levels of protein and certain specific amino acids. Nutrition support guidelines recommend provision of >1.5 g/kg/d of protein and indicate that higher levels may be needed. Protein composition is also important. There is good evidence that leucine can promote anabolism in patients with cancer and sarcopenia. Finally, anabolic interventions-including intensive insulin, oxandrolone, propranolol, and resistance exercise-have proven to be effective in patients with major burns and are likely relevant in combating PICS cachexia.

Protein and Calorie Requirements Associated With the Presence of Obesity

Obesity compounds the metabolic response to critical illness and increases the risk for overfeeding complications due to its comorbidities. Hypocaloric, high-protein nutrition therapy affords the hospitalized patient with obesity the opportunity to achieve net protein anabolism with a reduced risk of overfeeding complications. The intent of this review is to provide the theoretical framework for development of a hypocaloric high-protein regimen, scientific evidence to support this mode of therapy, and unique considerations for its use in specialized subpopulations. Macronutrient goals and practical suggestions for patient monitoring are given.

Changes in Lean Mass and Serum Myostatin with Habitual Protein Intake and High-Velocity Resistance Training

OBJECTIVES

Examine the associations between dietary protein intake, lean mass (LM), and serum myostatin (Mstn) levels among community-dwelling older adults participating in a 20-week high-velocity resistance training (HVRT) program.

DESIGN, SETTING, AND PARTICIPANTS

This longitudinal study consisted of 33 community-dwelling, older adults (mean age 77.0 years, SD = 6.4); all of which obtained physician clearance prior to study participation.

MEASUREMENTS

Twenty-five females and eight males were randomized to a control (CON) or HVRT group. Anthropometric measures were obtained via dual energy x-ray absorptiometry (DXA) and peripheral venous blood draw used for serum myostatin analysis. Exercise was performed twice per week for 20 consecutive weeks. Food intake estimation with a diet history questionnaire (DHQ) was used for protein intake comparison to the recommended dietary allowance (RDA). All measures were recorded both prior to and following study participation.

RESULTS

Altogether, protein was consumed in amounts more generous (1.01 ± 0.47 g·kg-1·d-1) than that of the RDA (0.8 g·kg-1·d-1). As a result of significant LM differences among men and women (p < 0.01), additional data were analyzed specific to sex. Serum myostatin was greater among females (6681.8 ± 3155.0 pg·mL-1) than males (5560.0 ± 2946.1 pg·mL-1); however, these values were not significantly different (p = 0.39). Combined, protein consumption and serum myostatin did not significantly influence LM among males (p = 0.09) or females (p = 0.71). Irrespective of training group, significant changes were not exhibited in dietary intake patterns, LM, or serum myostatin.

CONCLUSIONS

Contrary to the proposed hypothesis, results suggest protein consumption and circulating serum myostatin levels did not significantly influence LM among older adults. Although HVRT positively impacts LM, neither exercise group displayed significant changes in LM. Therefore, further research is needed examining dietary intake, exercise modality, and myostatin downregulation as non-pharmacological approaches to combating sarcopenia.

Effect of a High-Protein Energy-Restricted Diet Combined with Resistance Training on Metabolic Profile in Older Individuals with Metabolic Impairments

Adequate protein intake and resistance training are effective strategies to maintain muscle mass, but the effect of their combination on metabolic profile during weight loss remains to be determined in older adults. The main objective of this study was to determine the effect of a 16-week high-protein caloric restriction combined with resistance training on chronic disease risk factors in obese older individuals with metabolic impairments. A total of 26 overweight adults aged between 60 and 75 years (BMI 32.4 ± 3.9 kg/m2) with at least 2 factors of the metabolic syndrome participated in this study and were randomized into two groups: 1) high-protein caloric restriction (HP; n= 12) and 2) high-protein caloric restriction combined with dynamic-resistance training (HP+RT; n=14). Caloric intake was reduced by 500 kcal/d in all participants and protein intake equated 25-30% of total calories (~1.4 g/kg/d). Exercise training consisted of 3 session/week of resistance training on pulley machines. Outcome measures included total and trunk fat mass (FM), total and appendicular lean body mass (LBM), fasting glucose level, lipid profile and blood pressure. Our results showed that total and trunk FM (all p<0.0001) as well as fasting glucose (p<0.0001), triglycerides (p=0.002) and total cholesterol (p=0.03) levels decreased similarly in both groups. However, total (p=0.04) and appendicular (p=0.02) LBM decreased in the HP group only. Our data show that high-protein energy restriction improves health profile of obese elderly at high risk of chronic disease but needs to be combined with resistance training to maintain LBM.

Diet Modeling in Older Americans: The Impact of Increasing Plant-Based Foods or Dairy Products on Protein Intake

OBJECTIVES

To determine the effects of increasing plant-based foods or dairy products on protein intake in older Americans by performing diet modeling.

DESIGN

Data from What We Eat in America (WWEIA), the dietary component of the National Health and Nutrition Examination Survey (NHANES), 2007-2010 for Americans aged 51 years and older (n=5,389), divided as 51-70 years (n=3,513) and 71 years and older (n=1,876) were used.

MEASUREMENTS

Usual protein intake was compared among three dietary models that increased intakes by 100%: (1) plant-based foods; (2) higher protein plant-based foods (i.e., legumes, nuts, seeds, soy); and (3) dairy products (milk, cheese, and yogurt). Models (1) and (2) had commensurate reductions in animal-based protein intake.

RESULTS

Doubling intake of plant-based foods (as currently consumed) resulted in a drop of protein intake by approximately 22% for males and females aged 51+ years. For older males and females, aged 71+ years, doubling intake of plant-based foods (as currently consumed) resulted in an estimated usual intake of 0.83±0.02 g/kg ideal body weight (iBW))/day and 0.78±0.01 g/kg iBW/day, respectively. In this model, 33% of females aged 71+ years did not meet the estimated average requirement for protein. Doubling dairy product consumption achieved current protein intake recommendations.

CONCLUSION

These data illustrate that increasing plant-based foods and reducing animal-based products could have unintended consequences on protein intake of older Americans. Doubling dairy product intake can help older adults get to an intake level of approximately 1.2 g/kg iBW/day, consistent with the growing consensus that older adults need to consume higher levels of protein for health.

Protein Enrichment of Familiar Foods as an Innovative Strategy to Increase Protein Intake in Institutionalized Elderly

OBJECTIVE

To increase the protein intake of older adults, protein enrichment of familiar foods and drinks might be an effective and attractive alternative for oral nutritional supplements (ONS). We performed a pilot study to test whether these products could help institutionalized elderly to reach a protein intake of 1.2 gram per kg body weight per day (g/kg/d).

DESIGN

Intervention study with one treatment group (no control group). Dietary assessment was done before and at the end of a 10-day intervention.

SETTING

Two care facilities in Gelderland, the Netherlands: a residential care home and a rehabilitation center.

PARTICIPANTS

22 elderly subjects (13 women, 9 men; mean age 83.0±9.4 years).

INTERVENTION

We used a variety of newly developed protein enriched regular foods and drinks, including bread, soups, fruit juices, and instant mashed potatoes.

MEASUREMENTS

Dietary intake was assessed on two consecutive days before and at the end of the intervention, using food records filled out by research assistants. Energy and macronutrient intake was calculated using the 2013 Dutch food composition database. Changes in protein intake were evaluated using paired t-tests.

RESULTS

Protein intake increased by 11.8 g/d (P=0.003); from 0.96 to 1.14 g/kg/d (P=0.002). This increase is comparable to protein provided by one standard portion of ONS. The intake of energy and other macronutrients did not change significantly. At the end of the intervention more elderly reached a protein intake level of 1.2 g/kg/d than before (9 vs 4). Protein intake significantly increased during breakfast (+3.7 g) and during the evening (+2.2 g).

CONCLUSION

Including familiar protein enriched foods and drinks in the menu helped to meet protein recommendations in institutionalized elderly.

Development of novel fortified beef patties with added functional protein ingredients for the elderly

The effects of clean label functional protein ingredients; pea protein isolate (PPI), rice protein (RP) and lentil flour (LF), at 3% and 7% inclusion levels on technological and shelf life parameters of beef patties were evaluated over 12days. Protein content in the RP7 treatment was higher (P<0.05) than controls, but did not differ significantly from PPI7 and RP3. No effects on moisture, fat or ash content were detected. LF addition reduced product hardness, cohesiveness, gumminess and chewiness compared with controls. RP-enriched and control patties were associated with lower lipid oxidation over storage than PPI- and LF-enriched patties. RP had a differential effect on (L*), (a*) and (b*) when compared with controls. Microbiological characteristics for all treatments were acceptable after 12days. Protein fortified beef patties with a softer texture and acceptable technological properties targeted for ease of consumption by older adults were produced in an attempt to reach dietary targeted protein requirements for this segment.

Dietary protein supplementation in the elderly for limiting muscle mass loss

Supplementation with whey and other dietary protein, mainly associated with exercise training, has been proposed to be beneficial for the elderly to gain and maintain lean body mass and improve health parameters. The main objective of this review is to examine the evidence provided by the scientific literature indicating benefit from such supplementation and to define the likely best strategy of protein uptake for optimal objectified results in the elderly. Overall, it appears that an intake of approximately 0.4 g protein/kg BW per meal thus representing 1.2-1.6 g protein/kg BW/day may be recommended taking into account potential anabolic resistance. The losses of the skeletal muscle mass contribute to lower the capacity to perform activities in daily living, emphasizing that an optimal protein consumption may represent an important parameter to preserve independence and contribute to health status. However, it is worth noting that the maximal intake of protein with no adverse effect is not known, and that high levels of protein intake is associated with increased transfer of protein to the colon with potential deleterious effects. Thus, it is important to examine in each individual case the benefit that can be expected from supplementation with whey protein, taking into account the usual protein dietary intake.

High-Protein Intake during Weight Loss Therapy Eliminates the Weight-Loss-Induced Improvement in Insulin Action in Obese Postmenopausal Women

High-protein (HP) intake during weight loss (WL) therapy is often recommended because it reduces the loss of lean tissue mass. However, HP intake could have adverse effects on metabolic function, because protein ingestion reduces postprandial insulin sensitivity. In this study, we compared the effects of ∼10% WL with a hypocaloric diet containing 0.8 g protein/kg/day and a hypocaloric diet containing 1.2 g protein/kg/day on muscle insulin action in postmenopausal women with obesity. We found that HP intake reduced the WL-induced decline in lean tissue mass by ∼45%. However, HP intake also prevented the WL-induced improvements in muscle insulin signaling and insulin-stimulated glucose uptake, as well as the WL-induced adaptations in oxidative stress and cell structural biology pathways. Our data demonstrate that the protein content of a WL diet can have profound effects on metabolic function and underscore the importance of considering dietary macronutrient composition during WL therapy for people with obesity.

Inflammaging and Skeletal Muscle: Can Protein Intake Make a Difference?

Inflammaging is the chronic low-grade inflammatory state present in the elderly, characterized by increased systemic concentrations of proinflammatory cytokines. It has been shown that inflammaging increases the risk of pathologic conditions and age-related diseases, and that it also has been associated with increased skeletal muscle wasting, strength loss, and functional impairments. Experimental evidence suggests that the increased concentrations of proinflammatory cytokines and primary tumor necrosis factor α observed in chronic inflammation lead to protein degradation through proteasome activation and reduced skeletal muscle protein synthesis (MPS) via protein kinase B/Akt downregulation. Dairy and soy proteins contain all the essential amino acids, demonstrate sufficient absorption kinetics, and include other bioactive peptides that may offer nutritional benefits, in addition to those of stimulating MPS. Whey protein has antioxidative effects, primarily because of its ability to enhance the availability of reduced glutathione and the activity of the endogenous antioxidative enzyme system. Soy protein and isoflavone-enriched soy protein, meanwhile, may counteract chronic inflammation through regulation of the nuclear transcription factor κB signaling pathway and cytokine production. Although evidence suggests that whey protein, soy protein, and isoflavone-enriched soy proteins may be promising nutritional interventions against the oxidative stress and chronic inflammation present in pathologic conditions and aging (inflammaging), there is a lack of information about the anabolic potential of dietary protein intake and protein supplementation in elderly people with increased systemic inflammation. The antioxidative and anti-inflammatory effects, as well as the anabolic potential of protein supplementation, should be further investigated in the future with well-designed clinical trials focusing on inflammaging and its associated skeletal muscle loss.

Exploring the functional mealtime associations of older adults through consumer segmentation and a means-end chain approach

Senior consumers are a rapidly growing and highly heterogeneous part of the world's population. This group does not always meet its recommended protein intake, which can negatively impact on their physical functioning and quality of life. To date, little is known about their motivations to consume protein-rich meals. In the current study, we therefore aim to identify consumer segments within the group of vital community-dwelling older adults on the basis of mealtime functionality (for example 'I eat because I'm hungry', or 'I eat because it is cosy'). To this end, we first conducted an online survey to identify these functional mealtime expectations of older consumers (study I, n = 398, 158 males, mean age 65.8 (y) ± 5.9 (SD)). To obtain further insights regarding mealtime functionality and proteins/protein enrichment, laddering interviews were conducted with a subgroup of the segmentation study participants (study II, n = 40, 20 males, mean age 66.9 (y) ± 4.8 (SD)). The results of the online survey showed three consumer clusters: cosy socialisers, physical nutritioners, and thoughtless rewarders. Thoughtless rewarders tend to eat without having explicit thoughts about it, they eat for the reward, and score highest on environmental awareness. Both the segmentation and the in-depth interviews showed that, for the cosy socialisers, the cosiness and social function of a meal are important motivators, whereas for the physical nutritioners the focus is more on the health and nutrient aspects of a meal. For cosy socialisers, protein enrichment can best be achieved through addition of protein-rich ingredients, whereas, for physical nutritioners, addition of protein powder is preferred. These results provide practical guidelines for the development of protein-rich meals and communication strategies tailored to the needs of specific vital community-dwelling older subgroups.

Feasibility of home-based dietetic intervention to improve the nutritional status of older adults post-hospital discharge

AIM

To determine if a model of home-based dietetic care improves dietary intake and weight status in a specific group of older adults post-hospitalisation.

METHODS

The Department of Veterans' Affairs clients aged 65 years and over were recruited from hospitals in a regional area of New South Wales, Australia (n = 32 men, n = 36 women). Nutritional status was assessed at home at baseline (within two weeks post-discharge) and three months post-discharge using a diet history, a food frequency checklist and Mini Nutritional Assessment (MNA). Personalised dietary advice was provided by a single dietitian according to participants' nutritional status.

RESULTS

Mean body weight improved significantly (P = 0.048), as well as mean MNA score (21.9 ± 3.5 vs 25.2 ± 3.1) (P < 0.001). Mean energy, protein and micronutrient intakes were adequate at baseline and three months, except for vitamin D. At three months, the underweight group (body mass index (BMI) < 23 kg/m² ) had significantly higher mean protein intake per body weight (1.7 ± 0.4 g/kg) compared to those who were a desirable weight (BMI 23-27 kg/m² ) (1.4 ± 0.3 g/kg) or overweight (BMI>27 kg/m² ) (1.1 ± 0.3 g/kg) peers (P < 0.001). There was significant improvement in energy intake contributed from oral nutrition supplements (+95.5 ± 388.2 kJ/day) and milk (+259.6 ± 659.8 kJ/day).

CONCLUSIONS

Dietetic intervention improved nutritional status 3 months after hospital discharge in older adults living in the community.

Protein quality as determined by the Digestible Indispensable Amino Acid Score: evaluation of factors underlying the calculation

The Food and Agriculture Organization of the United Nations recently recommended the adoption of a new and improved scoring system (Digestible Indispensable Amino Acid Score [DIAAS]) to quantify dietary protein quality. The DIAAS is based on the relative digestible content of the indispensable amino acids (IAAs) and the amino acid requirement pattern. Factors involved in calculation of the DIAAS include: use of the content and profile of IAAs as the basis for quality; methods for determination of the protein and amino acid content of the protein source; accuracy of individual requirement values for IAAs; normalization of IAA requirements by the estimated average requirement for protein; and basing the DIAAS on the true ileal digestibility of each IAA in the test protein. This review outlines the rationale for including each of these factors in the calculation of the DIAAS and describes associated potential errors.

Associations between body composition, nutrition, and physical activity in young adults

OBJECTIVE

The aim of the present study is to investigate the associations between total energy, macronutrient intakes, and physical activity (PA) and body composition by assessing body fat mass, fat-free mass, and BMI in a population of young adults.

METHODS

The study population consisted of 605 young Spanish adults (median age 20.38 ± 2.67). Body composition, including fat mass and fat-free mass, was calculated with body composition analyzer. Daily energy and macronutrient intakes were measured using a 72-h recall method. The International PA Questionnaire was used to assess PA and sedentary time. Linear regression analyses were performed to test the possible associations between nutrition, PA factors, and body composition.

RESULTS

Linear regression analyses revealed that BMI has a significant positive association with protein intake (P = .004, B = 0.088, 95% CI 0.028-0.149) and an inverse association with carbohydrate intake (P = 0.034, B = -0.027, 95% CI -0.053 - -0.002). Protein intake also demonstrated a significant association with fat-free mass, but the size of the effect was smaller (P = .027, B = 96.965, 95% CI 11.250-182.679). There was evidence of a positive association between total PA and moderate-to-vigorous PA (P < .001, B = 15.630, 95% CI 6.989 -24.270) and fat-free mass (P < .001, B = 20.208, 95% CI 9.694 -30.723). When fat mass was used as the outcome variable, there was no evidence of any association with the PA, total energy, and macronutrient intakes variables analyzed.

CONCLUSIONS

Our findings suggest that PA variables were consistently associated with body composition, specifically fat-free mass. Dietary factors also have influence over body composition; we showed that protein intake is significantly associated with fat-free mass and BMI.

Whey protein stories - An experiment in writing a multidisciplinary biography

This is an experimental, dual-purpose article about whey protein and how to conduct interdisciplinary analyses and writings. On the one hand, this article is a multidisciplinary commodity biography, which consists of five descriptions of whey protein written by the five different research groups involved in the interdisciplinary research project CALM(Counteracting Age-related loss of Skeletal Muscle Mass). On the other hand, it is a meta-analysis, which aims to uncover and highlight examples of how the five descriptions contribute to each other with insights into the contextualisation of knowledge, contrasts between the descriptions and the new dimensions they bring to established fields of interest. The meta-analysis also contains a discussion of interdisciplinary study objects and the usefulness of the multidisciplinary commodity biography as a format for interdisciplinary publications. The article contributes to the field of food studies with a multidisciplinary biography of whey protein - including its sensory qualities and challenges, insights into its cultural history, its nutritional value and effects on the human body and an analysis of how it is perceived by people who consume it. The biography thereby expands upon existing understandings of whey protein while discussing the usefulness of employing the commodity biography format in interdisciplinary writing. Moreover, the article contributes to the field of interdisciplinary research by providing a practical example of a joint publication and reflections upon the existence, interaction and possibilities of monodisciplinary knowledge structures within interdisciplinary studies and publications.

Dudrick Research Symposium 2015-Lean Tissue and Protein in Health and Disease

The 2015 Dudrick Research Symposium "Lean Tissue and Protein in Health and Disease: Key Targets and Assessment Strategies" was held on February 16, 2015, at Clinical Nutrition Week in Long Beach, California. The Dudrick Symposium honors the many pivotal and innovative contributions to the development and advancement of parenteral nutrition made by Dr Stanley J. Dudrick, physician scientist, academic leader, and a founding member of the American Society for Parenteral and Enteral Nutrition. As the 2014 recipient of the Dudrick award, Dr Carrie Earthman chaired the symposium and was the first of 3 speakers, followed by Dr Robert Wolfe and Dr Steven Heymsfield. The symposium addressed the importance of lean tissue to health and response to disease and injury, as well as the many opportunities and challenges in its assessment at the bedside. Lean tissue assessment is beneficial to clinical care in chronic and acute care clinical settings, given the strong relationship between lean tissue and outcomes, including functional status. Currently available bioimpedance techniques, including the use of bioimpedance parameters, for lean tissue and nutrition status assessment were presented. The connection between protein requirements and lean tissue was discussed, highlighting the maintenance of lean tissue as one of the most important primary end points by which protein requirements can be estimated. The various tracer techniques to establish protein requirements were presented, emphasizing the importance of practical considerations in research protocols aimed to establish protein requirements. Ultrasound and other new and emerging technologies that may be used for lean tissue assessment were discussed, and areas for future research were highlighted.

The Current Understanding of Sarcopenia: Emerging Tools and Interventional Possibilities

The purpose of this review is to provide health practitioners and physicians the most current state of the research on sarcopenia, its consequences, and to offer a summary of consensus guidelines for identification based on the most recent and compelling investigations and analyses. To accomplish this, the causes and consequences of sarcopenia will be described, and definitions and screening methods are updated. Importantly, interventional recommendations for sarcopenia will be discussed with a special emphasis on the effects of resistance training on sarcopenia-related outcomes. Furthermore, due to the increasing usage of hormone treatment as a strategy to combat sarcopenia, special consideration on the effects of hormone changes with aging and as interventions will be briefly reviewed.

New Horizons: Dietary protein, ageing and the Okinawan ratio

Nutrition has profound effects on ageing and lifespan. Caloric restriction is the major nutritional intervention that historically has been shown to influence lifespan and/or healthspan in many animal models. Studies have suggested that a reduction in protein intake can also increase lifespan, albeit not as dramatically as caloric restriction. More recent research based on nutritional geometry has attempted to define the effects of nutrition on ageing over a broad landscape of dietary macronutrients and energy content. Such studies in insects and mice indicate that animals with ad libitum access to low-protein, high-carbohydrate diets have longest lifespans. Remarkably, the optimum content and ratio of dietary protein to carbohydrates for ageing in experimental animals are almost identical to those in the traditional diets of the long-lived people on the island of Okinawa.

Protein Consumption and the Elderly: What Is the Optimal Level of Intake?

Maintaining independence, quality of life, and health is crucial for elderly adults. One of the major threats to living independently is the loss of muscle mass, strength, and function that progressively occurs with aging, known as sarcopenia. Several studies have identified protein (especially the essential amino acids) as a key nutrient for muscle health in elderly adults. Elderly adults are less responsive to the anabolic stimulus of low doses of amino acid intake compared to younger individuals. However, this lack of responsiveness in elderly adults can be overcome with higher levels of protein (or essential amino acid) consumption. The requirement for a larger dose of protein to generate responses in elderly adults similar to the responses in younger adults provides the support for a beneficial effect of increased protein in older populations. The purpose of this review is to present the current evidence related to dietary protein intake and muscle health in elderly adults.

Pork and Chicken Meals Similarly Impact on Cognitive Function and Strength in Community-Living Older Adults: A Pilot Study

A pilot quasi-experimental study investigated whether provision of pork, a rich source of thiamin, as the main protein source in meals four times/week for 12 weeks resulted in improved muscle mass, body strength, and cognitive function in community-living older adults compared to similar meals containing chicken. Retirement villages were randomized to receive pre-prepared frozen meals containing either pork or chicken. Dietary intake was assessed by three-day food records and cognitive domains assessed using validated tests. Hand grip strength was measured and lower extremity performance assessed by the sit-to-stand test, get-up-and-go test and six-minute walk test. Forty-eight volunteers participated (78.2 ± 6.2 y). In linear mixed models, controlling for baseline physical activity and dietary protein and energy intake, no differences were found between pork (n = 19) and chicken (n = 12) groups. The chicken group had improved Rey Auditory Verbal Learning test scores (verbal learning and memory) at six weeks (p < 0.001). Provision of four pork meals a week did not result in improvements in cognitive function, nor measures of strength or physical function, compared to those receiving chicken meals in healthy older adults. This suggests that merely changing the type of dietary protein provided by meat does not impact physical or cognitive function.

Nitrogen Balance and Protein Requirements for Critically Ill Older Patients

Critically ill older patients with sarcopenia experience greater morbidity and mortality than younger patients. It is anticipated that unabated protein catabolism would be detrimental for the critically ill older patient. Healthy older subjects experience a diminished response to protein supplementation when compared to their younger counterparts, but this anabolic resistance can be overcome by increasing protein intake. Preliminary evidence suggests that older patients may respond differently to protein intake than younger patients during critical illness as well. If sufficient protein intake is given, older patients can achieve a similar nitrogen accretion response as younger patients even during critical illness. However, there is concern among some clinicians that increasing protein intake in older patients during critical illness may lead to azotemia due to decreased renal functional reserve which may augment the propensity towards worsened renal function and worsened clinical outcomes. Current evidence regarding protein requirements, nitrogen balance, ureagenesis, and clinical outcomes during nutritional therapy for critically ill older patients is reviewed.

High dietary protein intake is associated with an increased body weight and total death risk

BACKGROUND & AIMS

High dietary protein diets are widely used to manage overweight and obesity. However, there is a lack of consensus about their long-term efficacy and safety. Therefore, the aim of this study was to assess the effect of long-term high-protein consumption on body weight changes and death outcomes in subjects at high cardiovascular risk.

METHODS

A secondary analysis of the PREDIMED trial was conducted. Dietary protein was assessed using a food-frequency questionnaire during the follow-up. Cox proportional hazard models were used to estimate the multivariate-adjusted hazard ratio (HR) and 95% confidence intervals (95%CI) for protein intake in relation to the risk of body weight and waist circumference changes, cardiovascular disease, cardiovascular death, cancer death and total death.

RESULTS

Higher total protein intake, expressed as percentage of energy, was significantly associated with a greater risk of weight gain when protein replaced carbohydrates (HR: 1.90; 95%CI: 1.05, 3.46) but not when replaced fat (HR: 1.69; 95%CI: 0.94, 3.03). However, no association was found between protein intake and waist circumference. Contrary, higher total protein intake was associated with a greater risk of all-cause death in both carbohydrate and fat substitution models (HR: 1.59; 95%CI: 1.08, 2.35; and HR: 1.66; 95%CI: 1.13, 2.43, respectively). A higher consumption of animal protein was associated with an increased risk of fatal and non-fatal outcomes when protein substituted carbohydrates or fat.

CONCLUSIONS

Higher dietary protein intake is associated with long-term increased risk of body weight gain and overall death in a Mediterranean population at high cardiovascular risk.

Barriers to and Facilitators of the Consumption of Animal-Based Protein-Rich Foods in Older Adults

Protein intakes in the older population can be lower than recommended for good health, and while reasons for low protein intakes can be provided, little work has attempted to investigate these reasons in relation to actual intakes, and so identify those of likely greatest impact when designing interventions. Questionnaires assessing: usual consumption of meat, fish, eggs and dairy products; agreement/disagreement with reasons for the consumption/non-consumption of these foods; and several demographic and lifestyle characteristics; were sent to 1000 UK community-dwelling adults aged 65 years and over. In total, 351 returned questionnaires, representative of the UK older population for gender and age, were suitable for analysis. Different factors were important for consumption of the four food groups, but similarities were also found. These similarities likely reflect issues of particular concern to both the consumption of animal-based protein-rich foods and the consumption of these foods by older adults. Taken together, these findings suggest intakes to be explained by, and thus that strategies for increasing consumption should focus on: increasing liking/tastiness; improving convenience and the effort required for food preparation and consumption; minimizing spoilage and wastage; and improving perceptions of affordability or value for money; freshness; and the healthiness of protein-rich foods.

Effects on the Qualities of Proteolysis to Beef by Non-coating and Coating Protease Treatment

This study was performed to improve the techniques used for tenderizing red meat as elderly food. Beef meat was immersed in liposome encapsulated enzyme solution and the effect of protease encapsulation on the beef properties was analyzed. The protease encapsulation properties were analyzed according to the size distribution and enzymatic activity. After enzyme reaction on the beef, the chemical properties of the meat such as pH, water holding capacity, shear rate, lipid oxidation and total volatile basic nitrogen (TVB-N) were analyzed. The pH of the beef increased during the reaction and coating protease (CP) was higher than non-coating protease (NCP). Total color differences were increased remarkably after 36 h and generally, the difference in CP was relatively lower than in NCP. WHC was significantly decreased within 24 h, and no effect from the protease coating was observed. Protease activity was significantly increased within 48 h and no differences in the enzyme coating were observed. The TVB-N value of NCP was increased within 24 h while CP was sustained for up to 36 h. The TVB-N value of protease treated meat increased after 36 h and no effect from the protease coating was detected. Consequently, liposome encapsulated protease was found to have similar properties as non-coated protease. Application of liposome seems to be an interesting option for injecting various functional materials without changing the properties of meat.

Outcome of a Targeted Nutritional Intervention Among Older Adults With Early-Stage Alzheimer's Disease: The Nutrition Intervention Study

A 6-month dietary intervention program was designed for community-dwelling older adults with Alzheimer's disease. Sixty-seven persons aged 70 years and above were recruited with their caregivers from six hospital memory and geriatric outpatient clinics, and allocated to intervention ( n = 34 dyads) or control group ( n = 33 dyads). Usual diet was assessed by a validated food frequency questionnaire and current diet by two nonconsecutive diet recalls or records corroborated by caregivers, at recruitment (T1) and exit from the study (T2). Intervention participants received targeted dietary recommendations; control participants received Canada's Food Guide leaflets. The program was assessed using paired and independent t tests and nonparametric statistics. Fat intakes increased at T2 within intervention participants (54 ± 16 vs. 67 ± 23 g, p = .013), and there was a tendency for higher energy, protein, and calcium intakes at T2 within this group. Proportions with adequate protein intakes almost doubled from T1 to T2 in intervention group women ( p = .028) but decreased in female controls ( p = .030). Longer follow-up is necessary to determine persistence of benefits.

Critical care: Meeting protein requirements without overfeeding energy

BACKGROUND AND AIMS

Relatively high protein input has been associated with improved clinical outcome in critical illness. However, until recently differences in clinical outcome have been examined in terms of the energy goal-versus under-feeding. Most studies failed to set the energy goal by an accurate measure or estimate of expenditure or independently set protein prescription. This leads to under-prescription of protein, possibly adversely affecting outcome. We determined whether an enteral nutrition prescription could meet local and international protein guidelines.

METHODS

Protein prescriptions of consecutive patients admitted to Southmead Hospital ICU and requiring full enteral nutrition were audited against local and international guidelines. Prescriptions were designed to not exceed energy expenditure based on a validated estimation equation, minus non-nutritional energy, and protein requirements were based on local or international guidelines of between 1.2 and 2.5 g protein/kg/d or 2-2.5/kg ideal body weight (Hamwi ideal body weight)/d.

RESULTS

From 15/1/15 to 12/4/15 139 ICU patients were prescribed full enteral nutrition. Protein prescriptions failed to meet local guidelines in 75% (p < 0.001) and international guidelines in 45-100%. Prescriptions meeting at least 90% of protein guidelines and 130 g of carbohydrate could be increased from between 0 and 55%, depending on the guideline, to between 53 and 94% using a protein supplement and 82 and 100% using a protein plus glucose supplement. Non-nutritional energy (NNE) proportionately reduces feed protein prescription and contributed 19% of energy expenditure in 10% of patients.

CONCLUSIONS

We need feeds with a lower non-protein energy: nitrogen (NPE:gN) ratio and/or protein supplementation if prescriptions are to meet protein guidelines for critical illness. NNE must be adjusted for in prescriptions to ensure protein needs are met.

Sarcopenic Obesity: An Appraisal of the Current Status of Knowledge and Management in Elderly People

Today's increased life expectancy highlights both age-related changes in body composition and a higher prevalence of obesity. Sarcopenic obesity (SO) is assuming a prominent role in cardio-metabolic risk because of the double metabolic burden derived from low muscle mass (sarcopenia) and excess adiposity (obesity). This review evaluates the related studies that have been published over the past 10 years in order to give an updated overview of this new syndrome. There is no consensus on the definition of SO due to the wide heterogeneity of diagnostic criteria and choice of body composition components needed to assess this phenotype. There is a growing body of evidence that the ethio-pathogenesis of SO is complex and multi-factorial, as the consequences are a combination of the outcomes of both sarcopenia and obesity, where the effects are maximised. In order to manage SO, it is important to make lifestyle changes that incorporate weight loss, physical exercise and protein supplementation.

Dietary Protein Intake in Dutch Elderly People: A Focus on Protein Sources

Introduction: Sufficient high quality dietary protein intake is required to prevent or treat sarcopenia in elderly people. Therefore, the intake of specific protein sources as well as their timing of intake are important to improve dietary protein intake in elderly people. Objectives: to assess the consumption of protein sources as well as the distribution of protein sources over the day in community-dwelling, frail and institutionalized elderly people. Methods: Habitual dietary intake was evaluated using 2- and 3-day food records collected from various studies involving 739 community-dwelling, 321 frail and 219 institutionalized elderly people. Results: Daily protein intake averaged 71 ± 18 g/day in community-dwelling, 71 ± 20 g/day in frail and 58 ± 16 g/day in institutionalized elderly people and accounted for 16% ± 3%, 16% ± 3% and 17% ± 3% of their energy intake, respectively. Dietary protein intake ranged from 10 to 12 g at breakfast, 15 to 23 g at lunch and 24 to 31 g at dinner contributing together over 80% of daily protein intake. The majority of dietary protein consumed originated from animal sources (≥60%) with meat and dairy as dominant sources. Thus, 40% of the protein intake in community-dwelling, 37% in frail and 29% in institutionalized elderly originated from plant based protein sources with bread as the principle source. Plant based proteins contributed for >50% of protein intake at breakfast and between 34% and 37% at lunch, with bread as the main source. During dinner, >70% of the protein intake originated from animal protein, with meat as the dominant source. Conclusion: Daily protein intake in these older populations is mainly (>80%) provided by the three main meals, with most protein consumed during dinner. More than 60% of daily protein intake consumed is of animal origin, with plant based protein sources representing nearly 40% of total protein consumed. During dinner, >70% of the protein intake originated from animal protein, while during breakfast and lunch a large proportion of protein is derived from plant based protein sources.

Sex-based differences in endurance exercise muscle metabolism: impact on exercise and nutritional strategies to optimize health and performance in women

NEW FINDINGS

What is the topic of this review? The topic is how sex influences carbohydrate and fat metabolism during exercise and whether this influences adaptation to nutritional and exercise regimens aiming to improve health and performance. What advances does it highlight? Women respond differently to certain nutritional and training regimens aimed at improving health and performance. Few studies have included women in trials and thus we are unsure how women respond to nutritional and training strategies aimed at improving health and performance. Sex-based differences in substrate metabolism during moderate-intensity endurance exercise (END) have been well established. Specifically, during END of the same relative intensity women have a lower respiratory exchange ratio than men, indicative of a lesser reliance on carbohydrate oxidation to support fuel requirements for exercise. In fact, compared with men, women show a lesser reliance on both liver and muscle glycogen during END. Sex-based differences in intramyocellular lipid (IMCL) utilization during END are controversial. However, women have a larger depot of IMCL available to support END fuel needs and a greater percentage of IMCL in contact with mitochondria after a bout of END compared with men, suggestive of a greater capacity to use IMCL. These sex-based differences in metabolism during END are known to be mediated by oestrogen. Despite the well-recognized sexual dimorphisms in substrate metabolism during END, there is a paucity of research examining the effects of exercise and nutritional regimens aimed to enhance performance and/or health in women. Furthermore, the evidence that does exist is suggestive of discordance in the effectiveness of nutritional and exercise regimens between the sexes. The focus of this review is to provide an overview of the well-established sex-based differences in metabolism during END and how they relate to the physiological responses to nutritional and exercise strategies intended to improve exercise performance and/or health.

Digestion and Postprandial Metabolism in the Elderly

The elderly are an increasing segment of the population. Despite the rapid gains in medical knowledge and treatments, older adults are more likely to experience chronic illnesses that decrease quality of life and accelerate mortality. Nutrition is a key modifiable lifestyle factor which greatly impacts chronic disease risk. Yet despite the importance of nutrition, relatively little is known of the impact of advancing age on the gastrointestinal function, the digestive responses, and the post-meal metabolic adaptations that occur in response to ingested food. Knowledge of the age-related differences in digestion and metabolism in the elderly is essential to the development of appropriate nutritional recommendations for the maintenance of optimal health and prevention of disease.

Using a verbal prompt to increase protein consumption in a hospital setting: a field study

Background

Sufficient protein intake among hospitalized patients may contribute to faster recovery and a decrease in healthcare costs. Nevertheless, hospitalized patients are often found to consume too little protein. This field study explored the success of a small, inexpensive intervention adapted from the marketing literature, to encourage protein consumption among hospitalized patients.

Methods

The study was performed at a hospital where patients order food by calling to the meal service. The intervention consisted of a verbal prompt: “Would you like some [target product] with that?”, which was presented to patients by trained telephone operators, after patients finished ordering their lunch. Target products were two foods rich in protein; fruit quark and yoghurt drink. For half of the patients, the verbal prompt was preceded by verbal praise on their lunch order, which was aimed to increase compliance with the verbal prompt.

Results

Three hundred and fifteen hospitalized patients, aged 18–87 years took part in the study. Verbal prompts significantly increased ordering of the target products nearly sevenfold (from ordering by 6.5 % of patients to 45.2 % of patients). Protein content of ordered lunch and all food orders of the day combined showed a trend, with orders of patients receiving only a verbal prompt or a verbal prompt and verbal praise containing a larger amount of protein than lunch orders of patients in the control condition. At an individual level, protein content of ordered food increased significantly, reaching the 25–30 g of protein per main meal recommended by dieticians of the hospital. Verbal praise did not increase compliance with the verbal prompt. Patients consumed most or all of the target product and verbal prompts were not perceived to be obtrusive.

Conclusions

Although changing eating patterns is challenging, this study shows that simple interventions such as verbal prompts may be useful tools for health professionals to stimulate healthy food consumption among patients during hospitalization.

Effects of elastic band resistance training and nutritional supplementation on physical performance of institutionalised elderly--A randomized controlled trial

OBJECTIVES

To evaluate the effects of elastic band resistance training in combination with nutrient supplementation on muscular strength and the ability to perform mobility-related activities of daily living in older adults living in retirement care facilities.

DESIGN

Randomized controlled trial, with a 6-month intervention period.

SETTING

A retirement care facility, Vienna, Austria.

PARTICIPANTS

One hundred and seventeen older adults (14 males (12%) and 103 females (88%)), aged 65 to 97 years (mean age: 82.8 ± 6.0), having a mini-mental state examination score ≥ 23 and no chronic diseases posing a medical contraindication to training therapy.

INTERVENTION

Participants were randomly assigned, but stratified by sex, to one of three intervention groups: supervised resistance exercise training (RT), RT in combination with nutrient supplementation (RTS), or cognitive training group (CT). All interventions were performed two times a week for 6 months. RT was designed to train all major muscle groups using elastic bands. The nutrient supplement (rich in proteins, vitamin D, B2, B12) was distributed every morning as well as after each RT session.

MEASUREMENTS

A battery of motor ability tests and functional test were performed prior to as well as following 3 months and finally after 6 months of intervention. These tests included isokinetic torque measurements of the knee extensors and flexors in concentric mode at 60 and 120°/s, isometric handgrip strength, senior arm-lifting test, chair stand test, maximum walking speed and a 6-minute walking test (6 MWT).

RESULTS

A repeated-measures ANOVA analysis revealed significant improvements in physical function of lower (p=0.002) and upper extremities (p=0.006) for RT and/or RTS in comparison to CT. For isokinetic measurements, 6 MWT, and gait speed time effects (p<0.05) were detected without any group × time interaction effects. Dropouts showed lower performance in chair stand test (p=0.012), 6 MWT (p=0.003), and gait speed (p=0.013) at baseline than that of the finishers of the study.

CONCLUSION

Six months of a low intensity resistance exercise using elastic bands and own body weight is safe and beneficial in improving functional performance of institutionalised older people. Multinutrient supplementation did not offer additional benefits to the effects of RT in improving muscular performance.

Texture Softening of Beef and Chicken by Enzyme Injection Process

This research focuses on a new softening technology for use with chicken breast and eye of round beef in order to assist elderly individuals who have difficulty with eating due to changes in their ability to chew (masticatory function) or swallow. We investigated the hardness of chicken breast and eye of round beef through use of a texture analyzer after injection of a commercial enzyme. Among 7 commercial enzymes, bromelain and collupulin exhibited a marked softening effect on the tested chicken breast and eye of round beef given a 1.00% enzyme concentration. The hardness of bromelain-treated chicken breast reached 1.4×10(4) N/m(2), of collupulin-treated chicken breast reached 3.0×10(4) N/m(2), and of bromelain-treated eye of round beef reached 3.2×10(4) N/m(2), respectively, while their original shapes did not change. To find the level of tissue degradation with specific enzyme concentrations, enzyme injections at 0.1%, 0.25%, 0.50%, and 1.00% concentration of bromelain and papain were also evaluated. The results of this research could be useful for softening chicken breast and eye of round beef and will contribute to the development of foods that can be more easily eaten as part of a balanced diet for elderly adults.

Lean Body Mass Associated with Upper Body Strength in Healthy Older Adults While Higher Body Fat Limits Lower Extremity Performance and Endurance

Impaired strength adversely influences an older person’s ability to perform activities of daily living. A cross-sectional study of 117 independently living men and women (age = 73.4 ± 9.4 year; body mass index (BMI) = 27.6 ± 4.8 kg/m²) aimed to assess the association between body composition and: (1) upper body strength (handgrip strength, HGS); (2) lower extremity performance (timed up and go (TUG) and sit to stand test (STS)); and (3) endurance (6-minute walk (SMWT). Body composition (% fat; lean body mass (LBM)) was assessed using bioelectrical impedance. Habitual physical activity was measured using the Minnesota Leisure Time Physical Activity Questionnaire (MLTPA) and dietary macronutrient intake, assessed using 24 h recalls and 3-day food records. Regression analyses included the covariates, protein intake (g/kg), MLTPA, age and sex. For natural logarithm (Ln) of right HGS, LBM (p < 0.001) and % body fat (p < 0.005) were significant (r² = 46.5%; p < 0.000). For left LnHGS, LBM (p < 0.000), age (p = 0.036), protein intake (p = 0.015) and LnMLTPA (p = 0.015) were significant (r² = 0.535; p < 0.000). For SMW, % body fat, age and LnMLTPA were significant (r² = 0.346; p < 0.000). For STS, % body fat and age were significant (r² = 0.251; p < 0.000). LBM is a strong predictor of upper body strength while higher % body fat and lower physical activity are associated with poorer outcomes on tests of lower extremity performance.

Update on protein intake: importance of milk proteins for health status of the elderly

Loss of lean body mass that occurs with aging is the primary endpoint with which sarcopenia is defined. Furthermore, loss of muscle mass is central to the development of many adverse health issues in the elderly. Consequently, the response of lean body mass to nutritional interventions, particularly to dietary protein, has been a commonly measured endpoint. However, increased protein intake has been associated with improved markers for cardiovascular health, improved bone health, management of weight and metabolic diseases, and reduced all-cause mortality. Strength, rather than lean body mass, may be a more accurate indicator of health, especially in the elderly. The recommended dietary allowance for protein has been set at 0.8 g/kg/day. Because the average protein intake in the United States is approximately 1.2 g/kg/day, it appears that the average protein intake is above the recommended dietary allowance but below the low end of the acceptable macronutrient distribution range recommended by expert committees of the National Academy of Sciences and below the dietary intake levels suggested by the US Department of Agriculture in the Dietary Guidelines.

Protein: A nutrient in focus

Protein is an essential component of a healthy diet and is a focus of research programs seeking to optimize health at all stages of life. The focus on protein as a nutrient often centers on its thermogenic and satiating effect, and when included as part of a healthy diet, its potential to preserve lean body mass. A growing body of literature, including stable isotope based studies and longer term dietary interventions, suggests that current dietary protein recommendations may not be sufficient to promote optimal muscle health in all populations. A protein intake moderately higher than current recommendations has been widely endorsed by many experts and working groups and may provide health benefits for aging populations. Further, consuming moderate amounts of high-quality protein at each meal may optimally stimulate 24-h muscle protein synthesis and may provide a dietary platform that favors the maintenance of muscle mass and function while promoting successful weight management in overweight and obese individuals. Dietary protein has the potential to serve as a key nutrient for many health outcomes and benefits might be increased when combined with adequate physical activity. Future studies should focus on confirming these health benefits from dietary protein with long-term randomized controlled studies.

Mail-Based Intervention for Sarcopenia Prevention Increased Anabolic Hormone and Skeletal Muscle Mass in Community-Dwelling Japanese Older Adults: The INE (Intervention by Nutrition and Exercise) Study

OBJECTIVE

The aim of the Intervention by Nutrition and Exercise (INE) study was to investigate the effects of a mail-based intervention for sarcopenia prevention on muscle mass and anabolic hormones in community-dwelling older adults.

DESIGN

A cluster-randomized controlled trial.

SETTING AND PARTICIPANTS

This trial recruited community-dwelling adults aged 65 years and older in Japan. The 227 participants were cluster randomized into a walking and nutrition (W/N) group (n = 79), a walking (W) group (n = 71), and a control (C) group (n = 77). We analyzed the physical and biochemical measurements in this substudy.

INTERVENTION

Six months of mail-based intervention (a pedometer-based walking program and nutritional supplementation).

MEASUREMENTS

The skeletal muscle mass index (SMI) using the bioelectrical impedance data acquisition system, biochemical measurements, such as those of insulinlike growth factor (IGF-1), dehydroepiandrosterone sulfate (DHEA-S), and 25-hydroxy vitamin D (25[OH]D), as well as frailty, were assessed by the Cardiovascular Health Study criteria.

RESULTS

Participants in the W/N and W groups had significantly greater improvements in SMI, IGF-1, and 25(OH)D (P < .05) than those in the C group. Participants in the W/N group had significantly greater improvements in DHEA-S (P < .05) than in the other groups. These effects were more pronounced in frail, older adults.

CONCLUSION

These results suggest that the mail-based walking intervention of the remote monitoring type for sarcopenia prevention can increase anabolic hormone levels and SMI in community-dwelling older adults, particularly in those who are frail.

Dietary protein intake may reduce hospitalisation due to infection in Māori of advanced age: LiLACS NZ

OBJECTIVE

To investigate factors related to hospital admission for infection, specifically examining nutrient intakes of Māori in advanced age (80+ years).

METHOD

Face-to-face interviews with 200 Māori (85 men) to obtain demographic, social and health information. Diagnoses were validated against medical records. Detailed nutritional assessment using the 24-hour multiple-pass recall method was collected on two separate days. FOODfiles was used to analyse nutrient intake. National Health Index (NHI) numbers were matched to hospitalisations over a two-year period (12 months prior and 12 months following dietary assessment). Selected International Classification of Disease (ICD) codes were used to identify admissions related to infection.

RESULTS

A total of 18% of participants were hospitalised due to infection, most commonly lower respiratory tract infection. Controlling for age, gender, NZ deprivation index, diabetes, CVD and chronic lung disease, a lower energy-adjusted protein intake was independently associated with hospitalisation due to infection: OR (95%CI) 1.14 (1.00-1.29), p=0.046.

CONCLUSIONS

Protein intake may have a protective effect on the nutrition-related morbidity of older Māori. Improving dietary protein intake is a simple strategy for dietary modification aiming to decrease the risk of infections that lead to hospitalisation and other morbidities.

The Link between Dietary Protein Intake, Skeletal Muscle Function and Health in Older Adults

Skeletal muscle mass and function are progressively lost with age, a condition referred to as sarcopenia. By the age of 60, many older adults begin to be affected by muscle loss. There is a link between decreased muscle mass and strength and adverse health outcomes such as obesity, diabetes and cardiovascular disease. Data suggest that increasing dietary protein intake at meals may counterbalance muscle loss in older individuals due to the increased availability of amino acids, which stimulate muscle protein synthesis by activating the mammalian target of rapamycin (mTORC1). Increased muscle protein synthesis can lead to increased muscle mass, strength and function over time. This review aims to address the current recommended dietary allowance (RDA) for protein and whether or not this value meets the needs for older adults based upon current scientific evidence. The current RDA for protein is 0.8 g/kg body weight/day. However, literature suggests that consuming protein in amounts greater than the RDA can improve muscle mass, strength and function in older adults.

Nutritional supplements in support of resistance exercise to counter age-related sarcopenia

Age-related sarcopenia, composed of myopenia (a decline in muscle mass) and dynapenia (a decline in muscle strength), can compromise physical function, increase risk of disability, and lower quality of life in older adults. There are no available pharmaceutical treatments for this condition, but evidence shows resistance training (RT) is a viable and relatively low-cost treatment with an exceptionally positive side effect profile. Further evidence suggests that RT-induced increases in muscle mass, strength, and function can be enhanced by certain foods, nutrients, or nutritional supplements. This brief review focuses on adjunctive nutritional strategies, which have a reasonable evidence base, to enhance RT-induced gains in outcomes relevant to sarcopenia and to reducing risk of functional declines.