Meals containing equivalent total protein from foods providing complete, complementary, or incomplete essential amino acid profiles do not differentially affect 24-hour skeletal muscle protein synthesis in healthy, middle-aged women

BACKGROUND

Dietary protein quality can be assessed by skeletal muscle protein synthesis (MPS) stimulation. Limited knowledge exists on how consuming isonitrogenous meals with varied protein qualities affect postprandial and 24-h MPS.

OBJECTIVE

We assessed the effects of protein quality and complementary proteins on MPS. We hypothesized that meals containing a moderate amount of high-quality, complete protein would stimulate postprandial and 24-h MPS. Meals with two complementary, plant-based incomplete proteins would stimulate MPS less, and meals with plant-based incomplete proteins at each meal, but complementary over 24 h would not stimulate MPS.

DESIGN

This quasi-experimental study included a randomized, crossover design to assess protein quality and a non-randomized low-protein control. We measured postprandial and 24-h MPS responses of healthy middle-aged women (n=9, age 56±4 y), to three dietary conditions: isonitrogenous meals containing 23 g protein/meal from i) complete protein (lean beef); ii) two incomplete, but complementary protein sources (navy/black beans and whole wheat bread); and iii) single incomplete protein sources (black beans or whole wheat bread at a meal), but providing a complete amino acid profile over 24 h. In the low-protein group women (n=8, 54 ± 5 y) consumed a single breakfast meal containing 5 g of protein. Venous blood and vastus lateralis samples were obtained during primed, constant infusions of L-[ring-13C6] phenylalanine to measure mixed muscle fractional synthetic rates (FSR).

RESULTS

Meals with complete, complementary, or incomplete proteins did not differentially influence FSR responses after breakfast (p=0.90) or 24 h (p=0.38). At breakfast, the complete (p=0.030) and complementary (p=0.031) protein meals, but not the incomplete protein meal (p=0.38), had greater FSR responses, compared to the low-protein control meal.

CONCLUSIONS

Isonitrogenous meals containing a moderate serving of total protein from foods providing complete, complementary, or incomplete essential amino acid profiles do not differentially stimulate muscle protein synthesis after a meal and daily.

CLINICAL TRIALS REGISTRY

This clinical trial was registered at clinicaltrials.gov as NCT03816579. URL:; https://www.

CLINICALTRIALS

gov/ct2/show/NCT03816579?term=NCT03816579&draw=2&rank=1.

Impact of Dietary Patterns on Metabolic Syndrome in Young Adults: A Cross-Sectional Study

Metabolic syndrome has become a significant public health concern. This study aims to investigate the impact of dietary patterns on metabolic syndrome in young adults and how physical activity modulates this effect. A cross-sectional study was conducted at a health management center in Tianjin, China, from September 2022 to March 2023. Participants aged 18-35 years were recruited using convenience sampling. Dietary intake was assessed using a validated food frequency questionnaire. Logistic regression models evaluated associations between these patterns and metabolic syndrome, adjusting for potential confounders. Among 442 participants, four dietary patterns were identified: Legume-Nut, Alcohol-Meat, Sugar-Processed, and Egg-Vegetable. The Legume-Nut dietary pattern was associated with a higher risk of metabolic syndrome (OR = 2.63, 95% CI: 1.08-6.37), while the Egg-Vegetable dietary pattern was associated with a lower risk (OR = 0.26, 95% CI: 0.10-0.70). No significant associations were found for the Sugar-Processed and Alcohol-Meat patterns. Subgroup analysis revealed that the Legume-Nut pattern increased the risk of metabolic syndrome among those with irregular physical activity, whereas the Egg-Vegetable pattern decreased the risk. These findings highlight the significant influence of dietary patterns on the risk of metabolic syndrome in young adults and the modifying effect of regular physical activity, underscoring the need for targeted dietary and lifestyle interventions to prevent metabolic syndrome in this population.

Nutrition as the foundation for successful aging: a focus on dietary protein and omega-3 polyunsaturated fatty acids

Skeletal muscle plays a critical role throughout the aging process. People living with sarcopenia, a progressive and generalized loss of skeletal muscle mass and function, often experience diminished quality of life, which can be attributed to a long period of decline and disability. Therefore, it is important to identify modifiable factors that preserve skeletal muscle and promote successful aging (SA). In this review, SA was defined as (1) low cardiometabolic risk, (2) preservation of physical function, and (3) positive state of wellbeing, with nutrition as an integral component. Several studies identify nutrition, specifically high-quality protein (eg, containing all essential amino acids), and long-chain omega-3 polyunsaturated fatty acids (n-3 PUFAs), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), as positive regulators of SA. Recently, an additive anabolic effect of protein and n-3 PUFAs has been identified in skeletal muscle of older adults. Evidence further suggests that the additive effect of protein and n-3 PUFAs may project beyond skeletal muscle anabolism and promote SA. The key mechanism(s) behind the enhanced effects of intake of protein and n-3 PUFAs needs to be defined. The first objective of this review is to evaluate skeletal muscle as a driver of cardiometabolic health, physical function, and wellbeing to promote SA. The second objective is to examine observational and interventional evidence of protein and n-3 PUFAs on skeletal muscle to promote SA. The final objective is to propose mechanisms by which combined optimal intake of high-quality protein and n-3 PUFAs likely play a key role in SA. Current evidence suggests that increased intake of protein above the Recommended Dietary Allowance and n-3 PUFAs above the Dietary Guidelines for Americans recommendations for late middle-aged and older adults is required to maintain skeletal muscle mass and to promote SA, potentially through the mechanistical target of rapamycin complex 1 (mTORC1).

Tolerable Upper Intake Level for Individual Amino Acids in Humans: A Narrative Review of Recent Clinical Studies

Individual amino acids are widely popular as supplements because of various perceived and real health benefits. However, currently, there are no recommendations set by national health agencies for tolerable upper intake levels (UL) for amino acids because of a lack of well-conducted human dose-response trials. In the past decade, under the initiative of the International Council on Amino Acid Science, a nonprofit organization, a series of UL human clinical studies were conducted. The goal of this narrative review is to summarize the studies on 6 essential amino acids (leucine, tryptophan, methionine, lysine, histidine, and phenylalanine), 2 nonessential amino acids (arginine and serine), and 2 nonproteinogenic amino acids (ornithine and citrulline) and provide the first set of ULs. A brief background of the concept of the DRI framework of UL, the concept of UL for amino acids, and a perspective of the results are also provided. The data suggest that in relatively healthy adult individuals, the tested amino acids are well tolerated, and ULs, or the no-observed-adverse-effect-level (NOAEL), lowest-observed-adverse-effect-level (LOAEL), can be determined. The ULs were for leucine-young (35 g/d), tryptophan (4.5 g/d), and leucine-elderly (30 g/d); NOAEL and LOAEL for methionine at 3.2 and 6.4 g/d, respectively; NOAEL for arginine (30 g/d); NOAEL and LOAEL for lysine at 6 and 7.5 g/d, respectively; NOAEL and LOAEL for histidine at 8 and 12 g/d, respectively; and NOAEL for phenylalanine (12 g/d), serine (12 g/d), ornithine (12 g/d) and citrulline (24 g/d). This first set of human UL data are hoped to help national and international agencies set safety standards for supplemental amino acids.

Spent Yeast Valorization for Food Applications: Effect of Different Extraction Methodologies

Over the years, synthetic biology has been growing with the use of engineered yeast strains for the production of sustainable ingredients to meet global healthcare, agriculture, manufacturing and environmental challenges. However, as seen from the brewing industry perspective, these processes generate a substantial amount of spent yeast that contains high nutritional value related to its high protein content, showing its potential to be used as an alternative protein source. Taking into account the rising demand for protein because of the growth in the global population, the present study aims to produce peptide-rich extracts by different potentially scalable and sustainable methodologies in a circular economy approach for the food and nutraceutical industries. The results demonstrated that extraction from genetically modified strains allowed the production of extracts with an excellent nutritional profile and low molecular weight peptides. Furthermore, autolysis was shown to be a potential sustainable approach for this production, though other green metrics need to be explored in order to establish this process at an industrial level.

Review of protein intake and suitability of foods for protein-fortification in older adults in the UK

Protein is a vital dietary component for combating negative health outcomes associated with malnutrition in older adults, including sarcopenia, functional decline and reduced quality of life. Yet, recommended daily protein intake is consistently unmet, as evidenced in the literature and reaffirmed in this review. Poor appetite is recognized as a major determinant of protein-energy undernutrition and thus fortification of regular food or drinks provides a flexible and relevant approach for older adults with reduced appetite. To increase the likelihood of fortified products being successfully incorporated into the diets of older adults, they must be adaptable to older adults eating patterns, cater for their preferences and take the specific age-related problems that complicate food intake into account. This paper aims to highlight older adults' current sources of protein, shopping habits, typical eating patterns and commonly consumed foods, and hence consider appropriate carriers for protein enrichment. Data were reanalyzed from a combination of freely available UK datasets, including the National Dietary and Nutrition Survey and the Food and You Survey, alongside data purchased from market research consultancy, Kantar. These insights draw attention to the potential suitability of foods for fortification purposes, with the ultimate objective to promote eating pleasure and prevent malnutrition.

High protein diet-induced metabolic changes are transcriptionally regulated via KLF15-dependent and independent pathways

High protein diet (HPD) is an affordable and positive approach in prevention and treatment of many diseases. It is believed that transcriptional regulation is responsible for adaptation after HPD feeding and Kruppel-like factor 15 (KLF15), a zinc finger transcription factor that has been proved to perform transcriptional regulation over amino acid, lipid and glucose metabolism, is known to be involved at least in part in this HPD response. To gain more insight into molecular mechanisms by which HPD controls expressions of genes involved in amino acid metabolism in the liver, we performed RNA-seq analysis of mice fed HPD for a short period (3 days). Compared to a low protein diet, HPD feeding significantly increased hepatic expressions of enzymes involved in the breakdown of all the 20 amino acids. Moreover, using KLF15 knockout mice and in vivo Ad-luc analytical system, we were able to identify Cth (cystathionine gamma-lyase) as a new target gene of KLF15 transcription as well as Ast (aspartate aminotransferase) as an example of KLF15-independent gene despite its remarkable responsiveness to HPD. These findings provide us with a clue to elucidate the entire transcriptional regulatory mechanisms of amino acid metabolic pathways.

Effect of Deer Antler Extract on Muscle Differentiation and 5-Aminoimidazole-4-Carboxamide Ribonucleoside (AICAR)-Induced Muscle Atrophy in C2C12 Cells

The effect of deer antler extract on muscle differentiation and muscle atrophy were evaluated to minimize muscle loss following aging. Various deer antler extracts (HWE, hot water extract of deer antler; FE, HWE of fermented deer antler; ET, enzyme-assisted extract of deer antler; UE, extract prepared by ultrasonication of deer antler) were evaluated for their effect on muscle differentiation and inhibition of 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR)-induced muscle atrophy in C2C12 cells. Morphological changes according to the effect of antler extracts on muscle differentiation were confirmed by Jenner-Giemsa staining. In addition, the expression levels of genes related to muscle differentiation and atrophy were confirmed through qRT-PCR. In the presence of antler extracts, the length and thickness of myotubes and myogenin differentiation 1 (MyoD1) and myogenic factor 5 (Myf5) gene expression were increased compared to those in the control group (CON). Gene expression of AMP-activated protein kinase (AMPK), MyoD1, and myogenin, along with the muscle atrophy factors muscle RING finger-1 (MuRF-1) and forkhead box O3a (FoxO3a) upon addition of deer antler extracts to muscle-atrophied C2C12 cells was determined by qRT-PCR after treatment with AICAR. The expression of MuRF-1 and FoxO3a decreased in the groups treated with antler extracts compared to that in the group treated with AICAR alone. In addition, gene expression of MyoD1 and myogenin in the muscle atrophy cell model was significantly increased compared that into the CON. Therefore, our findings indicate that antler extract can increase the expression of MyoD1, Myf5 and myogenin, inhibit muscle atrophy, and promote muscle differentiation.

A practical nutritional guide for the management of sleep disturbances in menopause

Sleep disturbances (SD) represent one of the main symptoms of menopause and they are caused by several factors. Hormonal changes such as the reduction of oestrogen levels and the consequent vasomotor symptoms (VMS) along with psychiatric disorders such as depression and anxiety could contribute to the onset of SD. Furthermore, obesity per sè or through the obstructive sleep apnoea (OSA) could blunt sleep. Moreover, in menopause is usual a reduction in melatonin, that could contribute to SD. Nutritional strategies are paramount because they could contribute to manage menopause-related SD, in particular tackling obesity and overweight. Furthermore, some foods, such as soy, fish, whole grains, vegetables and fruit could decrease symptoms like depression and VMS, correlated with SD in postmenopausal women. Therefore, the aim of this review is to provide an overview of the current evidence on SD in menopause and to provide nutritional strategies for managing SD in this context.

Methods and Nutritional Interventions to Improve the Nutritional Status of Dialysis Patients in JAPAN-A Narrative Review

Patients receiving dialysis therapy often have frailty, protein energy wasting, and sarcopenia. However, medical staff in Japan, except for registered dietitians, do not receive training in nutritional management at school or on the job. Moreover, registered dietitians work separately from patients and medical staff even inside a hospital, and there are many medical institutions that do not have registered dietitians. In such institutions, medical staff are required to manage patients' nutritional disorders without assistance from a specialist. Recent studies have shown that salt intake should not be restricted under conditions of low nutrition in frail subjects or those undergoing dialysis, and protein consumption should be targeted at 0.9 to 1.2 g/kg/day. The Japanese Society of Dialysis Therapy suggests that the Nutritional Risk Index-Japanese Hemodialysis (NRI-JH) is a useful tool to screen for older patients with malnutrition.

Protein consumption in Canadian habitual diets: usual intake, inadequacy, and the contribution of animal- and plant-based foods to nutrient intakes

The 2019 Canada's Food Guide (CFG) emphasizes consumption of plant protein with implications for protein adequacy and nutrient intakes, yet a baseline with which to compare future dietary trends that may result from its adoption is not available. The objectives were to assess usual protein intake, inadequacy, and the contribution of animal- and plant-based foods to intake of protein, nutrients, and energy in Canada. Twenty-four-hour dietary recalls from the 2015 Canadian Community Health Survey - Nutrition were used to assess dietary intake among adults (n = 13 616). The National Cancer Institute method was used to estimate usual protein intake and inadequacy. Population ratios were used to determine the contribution of animal- and plant-based foods to intake of protein, nutrients, and energy. Usual protein intake averaged 79.47 ± 0.70 g/d; inadequacy was highest for females ≥71 y (9.76 ± 2.04%). Top protein contributors were red and processed meat (21.6 ± 0.55%), poultry and eggs (20.1 ± 0.81%), cereals, grains, and breads (19.5 ± 0.31%), and dairy (16.7 ± 0.38%). Dairy contributed most to calcium (53.4 ± 0.61%), vitamin D (38.7 ± 1.01%), but also saturated fat (40.6 ± 0.69%), whereas cereals, grains, and breads contributed most to iron (46.5 ± 0.57%) and vegetables and fruit to potassium (32 ± 0.45%). Given that animal sources contributed overwhelmingly to protein intake in 2015, dietary shifts towards plant protein needed to meet the 2019 CFG recommendations may pose a challenge, particularly for populations most at risk of inadequacy. Novelty: Older adults and females are most at risk of not meeting protein recommendations. Animal sources contribute two-thirds of the protein consumed by Canadian adults.

Effects of Casein, Chicken, and Pork Proteins on the Regulation of Body Fat and Blood Inflammatory Factors and Metabolite Patterns Are Largely Dependent on the Protein Level and Less Attributable to the Protein Source

The impact of meat protein on metabolic regulation is still disputed and may be influenced by protein level. This study aimed to explore the effects of casein, pork, and chicken proteins at different protein levels (40% E vs 20% E) on body weight regulation, body fat accumulation, serum hormone levels, and inflammatory factors/metabolites in rats maintained on high-fat (45% E fat) diets for 84 d. Increased protein levels resulted in a significant reduction in body fat mass and an increase in the serum levels of the anti-inflammatory cytokine IL-10, independent of protein source. Analysis of blood via untargeted metabolomics analysis identified eight, four, and four metabolites significantly altered by protein level, protein source, and a protein level-source interaction, respectively. Together, the effects of casein, chicken, and pork protein on the regulation of body fat accumulation and blood metabolite profile are largely dependent on protein level and less attributable to the protein source.

Dispensable Amino Acids, except Glutamine and Proline, Are Ideal Nitrogen Sources for Protein Synthesis in the Presence of Adequate Indispensable Amino Acids in Adult Men

BACKGROUND

Nutritionally, there is a dietary requirement for indispensable amino acids (IAAs) but also a requirement for nitrogen (N) intake for the de novo synthesis of the dispensable amino acids (DAAs). It has been suggested that there might be a dietary requirement for specific DAAs.

OBJECTIVES

Experiment 1 tested whether 9 of the DAAs (Ala, Arg, Asn, Asp, Gln, Glu, Gly, Pro, Ser) are ideal N sources using the indicator amino acid oxidation (IAAO) technique. Experiment 2 examined whether there is a dietary requirement for Glu in adult men.

METHODS

Seven healthy men (aged 20-24 y) participated in 11 or 2 test diet intakes, in experiment 1 and 2, respectively, in a repeated measures design. In experiment 1, a base diet consisting of the IAA provided at the RDA was compared with test intakes with the base diet plus addition of individual DAAs to meet a 50:50 ratio of IAA:DAA on an N basis. In experiment 2, the diets corresponded to the amino acid pattern present in egg protein, in which all Glu and Gln was present as Glu, or removed, with Ser used to make the diets isonitrogenous. On each study day the IAAO protocol with l-[1-13C]phenylalanine was used to measure whole-body protein synthesis.

RESULTS

In experiment 1, repeated measures ANOVA with post hoc multiple comparisons showed that 7 of the 9 DAAs (Ala, Arg, Asn, Asp, Glu, Gly, Ser) decreased IAAO significantly (P < 0.05) compared with base IAA diet, the exceptions being Gln and Pro. In experiment 2, a paired t test did not find significant (P > 0.05) differences in the IAAO in response to removal and replacement of Glu intake.

CONCLUSIONS

The results suggest that in healthy men most DAAs are ideal N sources for protein synthesis, in the presence of adequate IAAs, and that endogenous synthesis of Glu is sufficient.Registered clinicaltrials.gov identifier: NCT02009917.

Mediterranean diet as medical prescription in menopausal women with obesity: a practical guide for nutritionists

Menopausal transition is associated with weight gain and increased visceral fat distribution, which acts as an endocrine organ secreting the pro-inflammatory adipocytokines, which leads to metabolic disorders typical of menopause, including type 2 diabetes and cardiovascular diseases. Given the increasing number of aging population, the nutritional strategies to prevent obesity and obesity-related diseases in menopausal women is becoming a growing need and it should be one of the main objective for Nutritionists. The Mediterranean diet is characterized from foods with anti-inflammatory and antioxidant actions, such as extra-virgin olive oil, vegetables, fruits, legumes, nuts, red wine, and whole-grain cereals. Several evidences showed that the Mediterranean diet acts on both weight control and menopause, in addition to the known effects of the Mediterranean diet on cardiovascular and metabolic diseases. The Mediterranean diet is comparable with pharmacological interventions in terms of reducing the risk of obesity and cardiovascular and metabolic events. Considering that there are no specific dietary guidelines to manage weight in menopause, the aim of this review is to provide a nutritional guideline for the management of weight in menopause, particularly focusing on the Mediterranean diet.

The Phenylalanine Requirement of Elderly Men and Women Measured by Direct 13C Carbon Oxidation Method Is Similar to That of Young Adults

BACKGROUND

The phenylalanine requirement of the elderly is not known. Current recommendations are based on studies in young adults and are derived from a combined estimate of the total aromatic amino acids, phenylalanine, and tyrosine.

OBJECTIVES

The purpose of this study was to determine the dietary phenylalanine requirement of adults aged >65 y, using the direct amino acid oxidation method, by measuring the oxidation of l-[1-13C]phenylalanine to 13CO2 in response to graded phenylalanine intakes in the presence of excess tyrosine.

METHODS

Twelve subjects (6 men, 6 women), aged 73.8 ± 6.7 y (mean ± SD) and with a BMI (in kg/m2) of 26.4 ± 4.8 and 25.2 ± 4.4 for men and women, respectively, were randomized to phenylalanine intakes ranging from 7.20 to 40.0 mg .kg-1 .d-1 for a total of 66 studies. Study diets were isocaloric and isonitrogenous, providing protein and energy at 1.0 g .kg-1 .d-1 and 1.5 × resting energy expenditure (REE), respectively. Protein was provided as an amino acid mixture patterned after egg protein, with an excess of tyrosine and alanine to balance the nitrogen as phenylalanine intakes were varied. Two days prior to the study day, subjects were adapted to a milkshake diet providing protein at 1.0 g.kg-1 .d-1 and energy at 1.7 × REE. The mean phenylalanine requirement was determined using biphase linear regression analysis, which identified a breakpoint in the F13CO2 in response to graded phenylalanine intakes.

RESULTS

The mean and upper 95% CIs (approximating the recommended dietary allowance) of phenylalanine requirements were estimated to be 9.03 and 15.9 mg.kg-1 .d-1, respectively.

CONCLUSION

These results are similar to previously derived estimates of 9.1 and 13.6 mg.kg-1 .d-1 in young adult men and suggest that higher protein needs of the elderly to stimulate similar muscle protein synthesis rates as young adults are not driven by an increased requirement for phenylalanine. This trial was registered at clinicaltrials.gov as NCT02971059.

Dynamic Changes in Post-Ingestive Sensations after Consumption of a Breakfast Meal High in Protein or Carbohydrate

The obesity epidemic urges exploration of several parameters that play an important role in our eating behaviours. Post-ingestive sensations can provide a more comprehensive picture of the eating experience than mere satiety measurements. This study aimed to (1) quantify the dynamics of different post-ingestive sensations after food intake and (2) study the effect of protein and carbohydrate on hedonic and post-ingestive responses. Forty-eight participants (mean age 20.4) were served a breakfast meal high in protein (HighPRO) or high in carbohydrate (HighCHO) on two separate days using a randomised controlled crossover design. Post-ingestive sensations were measured every 30 min, for 3 h post intake using visual analogue scale (VAS). Results showed a significant main effect of time for all post-ingestive sensations. HighCHO induced higher hedonic responses compared to HighPRO, as well as higher ratings for post-ingestive sensations such as Satisfaction, Food joy, Overall wellbeing and Fullness. HighPRO, on the other hand, induced higher ratings for Sweet desire post intake. The development of sensations after a meal might be important for consumers' following food choices and for extra calorie intake. More detailed knowledge in this area could elucidate aspects of overeating and obesity.

Higher dietary protein intake preserves lean body mass, lowers liver lipid deposition, and maintains metabolic control in participants with long-chain fatty acid oxidation disorders

Medical nutrition therapy for long-chain fatty acid oxidation disorders (LC-FAODs) currently emphasizes fasting avoidance, restricted dietary long-chain fatty acid intake, supplementation with medium chain triglycerides, and increased carbohydrate intake. We hypothesize that increasing dietary protein intake relative to carbohydrate intake would preserve metabolic control yet induce physical benefits including reduced hepatic lipogenesis. Therefore, we compared two dietary approaches with similar fat intake but different carbohydrate to protein ratios in participants diagnosed with LC-FAODs. Thirteen participants were enrolled and randomized into either a high-protein (PRO) or a high-carbohydrate (CHO) diet for 4 months. Baseline and 4-month assessments included body composition, ectopic lipid deposition, and resting energy expenditure. End of study assessments also included total energy expenditure, metabolic responses to oral feedings, and whole-body fatty acid oxidation capacity. At the end of the dietary intervention, both groups had similar energy expenditure, fat and glucose oxidation rates, and glucolipid responses to mixed meal and oral glucose loads. Neither dietary group experienced worsening symptoms related to their LC-FAOD. Compared to the CHO group, the PRO group exhibited increased blood levels of short-chain acylcarnitines, reduced intrahepatic lipid content, and maintained lean body mass while the CHO group lost lean mass. In patients with LC-FAODs, increasing protein intake maintained metabolic control, reduced liver fat without risk of metabolic decompensation, and helped preserve lean body mass. We propose that a modest increase in dietary protein along with fasting avoidance and fat restriction may improve body composition and energy expenditure in patients with LC-FAODs.

Consumption of Milk and Alternatives and Their Contribution to Nutrient Intakes among Canadian Adults: Evidence from the 2015 Canadian Community Health Survey-Nutrition

As a staple food and dense source of nutrients, milk and alternatives play an important role in nutrient adequacy. The aims of this study were to quantify the consumption of milk and alternatives within Canadian self-selected diets and determine their contribution to intakes of nutrients and energy. First, 24-h dietary recalls from the 2015 Canadian Community Health Survey—Nutrition were used to assess 1-d food and nutrient intakes among Canadian adults ≥19 y (n = 13,616). Foods were classified as milk and alternatives according to the 2007 Canada’s Food Guide. Descriptive statistics were used to calculate daily servings of milk and alternatives by different age groups and demographic characteristics. Population ratios were used to discern their contribution to total intakes of nutrients and energy. Mean daily servings (±SE) were highest for milk (0.60 ± 0.02) and cheese (0.42 ± 0.01), intermediate for frozen dairy (0.16 ± 0.01) and yoghurt (0.14 ± 0.01), and lowest for soy and other dairy (<0.03). Intakes were lowest among Canadians 51 + y (1.3 ± 0.03), females (1.25 ± 0.03), non-Caucasians (1.06 ± 0.05), those with less than a secondary education (1.19 ± 0.05), and British Columbians (1.17 ± 0.05). Milk and alternatives contributed >20% to total intakes of calcium (52.62 ± 0.46%), vitamin D (38.53 ± 0.78%), saturated fat (28.84 ± 0.51%), vitamin B12 (27.73 ± 0.57%), vitamin A (26.16 ± 0.58%), phosphorus (24.76 ± 0.35%), and riboflavin (24.43 ± 0.37%), of which milk was the top source. Milk and alternatives contribute substantially to nutrient intakes and thus warrant further attention in terms of mitigating nutrient inadequacy among the Canadian population.

The Effect of Block Versus Daily Undulating Periodization on Strength and Performance in Adolescent Football Players

Purpose: Muscle mass, strength, and power are important factors for performance. To improve these characteristics, periodized resistance training is used. However, there is no consensus regarding the most effective periodization model. Therefore, the purpose of this study was to compare the effects of block (BLOCK) vs daily undulating periodization (DUP) on body composition, hypertrophy, strength, performance, and power in adolescent American football players. Methods: A total of 47 subjects participated in this study (mean [SD] age = 17 [0.8] y, strength training experience = 0.93 [0.99] y). Premeasurements and postmeasurements consisted of body mass (BM); fat mass; relative fat mass; fat-free mass (FFM); muscle mass (MM); muscle thickness of the vastus lateralis (VL), rectus femoris (RF), and triceps brachii (TB); 1-repetition-maximum back squat (BS) and bench press (BP); countermovement jump (CMJ); estimated peak power (Wpeak) from vertical jump performance; medicine-ball put (MBP); and 40-yd sprint. Subjects were randomly assigned in either the BLOCK or DUP group prior to the 12-wk intervention period consisting of 3 full-body sessions per week. Results: Both groups displayed significantly higher BM (P < .001), FFM (P < .001), MM (P < .001), RF (P < .001), VL (P < .001), TB (P < .001), BS (P < .001), BP (P < .001), CMJ (P < .001), Wpeak (P < .001), and MBP (P < .001) and significantly lower sprint times (P < .001) after 12 wk of resistance training, with no difference between groups. Conclusions: Resistance training was effective to increase muscle mass, strength, power, and performance in adolescent athletes. BLOCK and DUP affect anthropometric measures and physical performance equally.

Pre-operative nutrition and the elective surgical patient: why, how and what?

Pre-operative nutrition therapy is increasingly recognised as an essential component of surgical care. The present review has been formatted using Simon Sinek's Golden Circle approach to explain 'why' avoiding pre-operative malnutrition and supporting protein anabolism are important goals for the elective surgical patient, 'how' peri-operative malnutrition develops leading in part to a requirement for pre-operative anabolic preparation, and 'what' can be done to avoid pre-operative malnutrition and support anabolism for optimal recovery.

Evaluation of the biological quality of defatted pequi (Caryocar brasiliense Cambess) seed flour protein supplemented with lysine to rats (Rattus norvegicus)

ABSTRACT Objective In the biome of the Brazilian Cerrado, there are a lot of fruit tree species that stand out for their sensory quality and for presenting potentialities in the market of pulp and almond. Among these species, the pequi deserves attention because it has an almond rich in proteins and that is little explored. The aim of this study was to evaluate the biological quality of defatted pequi seed flour supplemented with lysine. Methods Two designs were done in this study; in the first, the animals were divided into four diet groups: control, protein-free, defatted pequi seed flour and defatted pequi seed flour supplemented with lysine. The protein-free diet was exempt of proteins and the other diets had a protein content of 10% and differed in protein source (casein: control diet or defatted pequi seed flour: test diets). The experiment lasted for 14 days. In the second design, 36 animals were used and followed-up for 28 days. The division of the experimental groups was kept, except for the protein-free diet group, which was excluded. By the end of the test, the animals were anaesthetised and euthanized. Results The results showed that the protein efficiency ratio of the control group was significantly higher than the other groups. For the other indices, the groups that received defatted pequi seed flour did not differ statistically among themselves. Conclusion These findings have shown an effect of supplementation on the protein efficiency ratio when comparing the test diets, however, when compared to the control group, no improvement was found.

Nutrition and physical performance in older people-effects of marine protein hydrolysates to prevent decline in physical performance: a randomised controlled trial protocol

INTRODUCTION

Age-related loss of muscle mass, muscle strength and muscle function (sarcopenia) leads to a decline in physical performance, loss of independence and reduced quality of life. Nutritional supplements may delay the progression of sarcopenia. The aim of this randomised, double-blinded controlled trial including 100 participants (≥65 years) is to assess the effect of a marine protein hydrolysate (MPH) on sarcopenia-related outcomes like hand grip strength, physical performance or gait speed and to study the associations between physical performance and nutritional intake and status.

METHOD AND ANALYSIS

The intervention group (n=50) will receive 3 g of MPH per day in 12 months. The control group (n=50) receive placebo. Assessments of Short Physical Performance Battery (SPPB), hand grip strength, anthropometric measurements, nutritional status as measured by the Mini Nutritional Assessment, dietary intake, supplement use, biomarkers of protein nutrition and vitamin D, and health-related quality of life (EQ-5D), will be performed at baseline and after 6 and 12 months of intervention. Linear mixed models will be estimated to assess the effect of MPH on SPPB, hand grip strength and quality of life, as well as associations between physical performance and nutrition.

ETHICS AND DISSEMINATION

The study has been approved by the Regional Committee in Ethics in Medical Research in Mid-Norway in September 2016 with the registration ID 2016/1152. The results will be actively disseminated through peer-reviewed journals, conference presentations, social media, broadcast media and print media.

TRIAL REGISTRATION NUMBER

NCT02890290.

Purified Dietary Red and White Meat Proteins Show Beneficial Effects on Growth and Metabolism of Young Rats Compared to Casein and Soy Protein

This study compared the effects of casein, soy protein (SP), red (RMP), and white meat (WMP) proteins on growth and metabolism of young rats. Compared to casein, the ratio of daily feed intake to daily body weight gain of rats was not changed by meat protein but reduced by SP by 93.3% ( P < 0.05). Feeding RMP and WMP reduced the liver total cholesterol (TC) contents by 24.3% and 17.8%, respectively ( P < 0.05). Only RMP increased plasma HDL-cholesterol concentrations (by 12.7%, P < 0.05), whereas SP increased plasma triacylglycerol, TC, and LDL-cholesterol concentrations by 23.7%, 19.5%, and 61.5%, respectively ( P < 0.05). Plasma essential and total amino acid concentrations were increased by WMP (by 18.8% and 12.4%, P < 0.05) but reduced by SP (by 28.3% and 37.7%, P < 0.05). Twenty-five liver proteins were differentially expressed in response to different protein sources. Therefore, meat proteins were beneficial for growth and metabolism of young rats compared to casein and SP.

Lessons from animal nutritionists: dietary amino acid requirement studies and considerations for healthy aging studies

Dietary restriction (DR) increases median life span and protects against age-related disease. Improved longevity can be achieved by restriction of dietary energy, protein, or amino acids (AAs), such as methionine (Met). Met requirements have been defined using methodologies that measure the dose response to Met when all other dietary variables are held constant and with outcomes focused on protein turnover. Here, we cover protein and sulfur AA requirements and discuss the terms "deficient," "optimal," and "excess" and how these need to be considered. We additionally discuss the effect of methyl-donating compounds on sulfur AA metabolism and outcomes. We will discuss how the mechanistic target of rapamycin complex 1 (mTORC1) signaling network regulates protein turnover, lipogenesis and cell growth, proliferation, differentiation, and metabolism in response to hormones, AAs, and cellular energy status. Inhibition of mTORC1 signaling with rapamycin or genetic mutation increases median life span in model organisms, and mTORC1 inhibition may be responsible for some of the life span-extending effects of DR. Finally, we discuss how the sulfur AAs may regulate aspects of reactive oxygen species (ROS) mitigation. Overall, we suggest that approaches evaluating AA intake need to consider whole-body protein synthesis and measures related to tissue-specific and whole-body metabolism that have been associated with longevity.

Muscle Protein Signaling in C2C12 Cells Is Stimulated to Similar Degrees by Diverse Commercial Food Protein Sources and Experimental Soy Protein Hydrolysates

Dietary protein stimulates muscle protein synthesis and is essential for muscle health. We developed a screening assay using C2C12 mouse muscle cells to assess the relative abilities of diverse commercial protein sources and experimental soy protein hydrolysates (ESH), after simulated gut digestion (SGD), to activate the mechanistic target of rapamycin complex I (mTORC1) muscle protein synthesis signaling pathway (p70S6K^(Thr389) phosphorylation). Activation of mTORC1 was expressed as a percentage of a maximal insulin response. The bioactivities of proteins grouped by source including fish (81.3 ± 10.6%), soy (66.2 ± 4.7%), dairy (61.8 ± 4.3%), beef (53.7 ± 8.6%), egg (52.3 ± 10.6%), soy whey (43.4 ± 8.6%), and pea (31.4 ± 10.6%) were not significantly different from each other. Bioactivity for ESH ranged from 28.0 ± 7.5 to 98.2 ± 6.6%. The results indicate that both the protein source and processing conditions are key determinants for mTORC1 activation. Regression analyses demonstrated that neither leucine nor total branched-chain amino acid content of proteins is the sole predictor of mTORC1 activity and that additional factors are necessary.

Animal Models for the Study of the Relationships between Diet and Obesity: A Focus on Dietary Protein and Estrogen Deficiency

Obesity is an increasing major public health concern asking for dietary strategies to limit weight gain and associated comorbidities. In this review, we present animal models, particularly rats and mice, which have been extensively used by scientists to understand the consequences of diet quality on weight gain and health. Notably, modulation of dietary protein quantity and/or quality has been shown to exert huge effects on body composition homeostasis through the modulation of food intake, energy expenditure, and metabolic pathways. Interestingly, the perinatal window appears to represent a critical period during which the protein intake of the dam can impact the offspring’s weight gain and feeding behavior. Animal models are also widely used to understand the processes and mechanisms that contribute to obesity at different physiological and pathophysiological stages. An interesting example of such aspect is the situation of decreased estrogen level occurring at menopause, which is linked to weight gain and decreased energy expenditure. To study metabolic disorders associated with such situation, estrogen withdrawal in ovariectomized animal models to mimic menopause are frequently used. According to many studies, clear species-specific differences exist between rats and mice that need to be taken into account when results are extrapolated to humans.

Variation in Protein Origin and Utilization: Research and Clinical Application

Muscle health can be rapidly compromised in clinical environments. Modifiable strategies to preserve metabolic homeostasis in adult patient populations include physical activity and pharmacologic support; however, optimizing dietary practices, or more specifically protein intake, is a necessary prerequisite for any other treatment strategy to be fully effective. Simply increasing protein intake is a well-intentioned but often unfocused strategy to protect muscle health in an intensive care setting. Protein quality is a frequently overlooked factor with the potential to differentially influence health outcomes. Quality can be assessed by a variety of techniques, with digestible indispensable amino acid score being the current and most comprehensive technique endorsed by the Food and Agriculture Organization. In practical terms, animal-based proteins are consistently scored higher in quality compared with incomplete proteins, regardless of the assessment method. Consequently, choosing parenteral and/or enteral feeding options that contain high-quality proteins, rich in the branched-chain amino acid leucine, may help establish a dietary framework with the potential to support clinical practice and improve health outcomes in critically ill patients.

Defining malnutrition: A plea to rethink

In a recent consensus report in Clinical Nutrition the undernourished category of malnutrition was proposed to be defined and diagnosed on the basis of a low BMI or unintentional weight loss combined with low BMI or FFMI with certain cut off points. The definition was endorsed by ESPEN despite recent endorsement of a very different definition. The approach aims to assess whether nutritional intake is sufficient but is imprecise because a low BMI does not always indicate malnutrition and individuals with increasing BMI's may have decreasing FFM's. The pathophysiology of individuals, considered to be malnourished in rich countries and in areas with endemic malnutrition, results predominantly from deficient nutrition combined with infection/inflammation. Both elements jointly determine body composition and function and consequently outcome of disease, trauma or treatment. When following the consensus statement only an imprecise estimate is acquired of nutritional intake without knowing the impact of inflammation. Most importantly, functional abilities are not assessed. Consequently it will remain uncertain how well the individual can overcome stressful events, what the causes are of dysfunction, how to set priorities for treatment and how to predict the effect of nutritional support. We therefore advise to consider the pathophysiology of malnourished individuals leading to inclusion of the following elements in the definition of malnutrition: a disordered nutritional state resulting from a combination of inflammation and a negative nutrient balance, leading to changes in body composition, function and outcome. A precise diagnosis of malnutrition should be based on assessment of these elements.

Protein-Pacing and Multi-Component Exercise Training Improves Physical Performance Outcomes in Exercise-Trained Women: The PRISE 3 Study

The beneficial cardiometabolic and body composition effects of combined protein-pacing (P; 5-6 meals/day at 2.0 g/kg BW/day) and multi-mode exercise (resistance, interval, stretching, endurance; RISE) training (PRISE) in obese adults has previously been established. The current study examines PRISE on physical performance (endurance, strength and power) outcomes in healthy, physically active women. Thirty exercise-trained women (>4 days exercise/week) were randomized to either PRISE (n = 15) or a control (CON, 5-6 meals/day at 1.0 g/kg BW/day; n = 15) for 12 weeks. Muscular strength (1-RM bench press, 1-RM BP) endurance (sit-ups, SUs; push-ups, PUs), power (bench throws, BTs), blood pressure (BP), augmentation index, (AIx), and abdominal fat mass were assessed at Weeks 0 (pre) and 13 (post). At baseline, no differences existed between groups. Following the 12-week intervention, PRISE had greater gains (p < 0.05) in SUs, PUs (6 ± 7 vs. 10 ± 7, 40%; 8 ± 13 vs. 14 ± 12, 43% ∆reps, respectively), BTs (11 ± 35 vs. 44 ± 34, 75% ∆watts), AIx (1 ± 9 vs. -5 ± 11, 120%), and DBP (-5 ± 9 vs. -11 ± 11, 55% ∆mmHg). These findings suggest that combined protein-pacing (P; 5-6 meals/day at 2.0 g/kg BW/day) diet and multi-component exercise (RISE) training (PRISE) enhances muscular endurance, strength, power, and cardiovascular health in exercise-trained, active women.

Canadian Consensus on Female Nutrition: Adolescence, Reproduction, Menopause, and Beyond

OBJECTIVES

To provide health care professionals in Canada with the basic knowledge and tools to provide nutrition guidance to women through their lifecycle.

OUTCOMES

Optimal nutrition through the female lifecycle was evaluated, with specific focus on adolescence, pre-conception, pregnancy, postpartum, menopause, and beyond. The guideline begins with an overview of guidance for all women, followed by chapters that examine the evidence and provide recommendations for the promotion of healthy nutrition and body weight at each life stage. Nutrients of special concern and other considerations unique to each life stage are discussed in each chapter.

EVIDENCE

Published literature, governmental and health agency reports, clinical practice guidelines, grey literature, and textbook sources were used in supporting the recommendations made in this document.

VALUES

The quality of evidence was rated using the criteria described in the report of the Canadian Task Force on Preventive Health Care. CHAPTER 2: GENERAL FEMALE NUTRITION: Summary Statements Recommendations CHAPTER 3: ADOLESCENCE NUTRITION: Summary Statements Recommendations CHAPTER 4: PRE-CONCEPTUAL NUTRITION: Summary Statement Recommendations CHAPTER 5: NUTRITION IN PREGNANCY: Summary Statements Recommendations CHAPTER 6: POSTPARTUM NUTRITION AND LACTATION: Summary Statements Recommendations CHAPTER 7: NUTRITION DURING MENOPAUSE AND BEYOND: Summary Statement Recommendations.

Protein and energy intake improved by breakfast intervention in hospital

BACKGROUND/AIM

Undernutrition affects about 40% of patients in hospitals. Ordinary food is recommended as the first choice to prevent and correct undernutrition. Meanwhile, sufficient intake, especially regarding protein, is difficult to reach, in patients at nutritional risk. The aim of this study was to improve protein intake at breakfast to at least 20% of total daily requirement or at least 20 g.

METHODS

A protein rich breakfast including 20 g of protein was served in the departments of heart and lung surgery and vascular surgery for three months. Nutrition intake was registered before and after intervention.

RESULTS

Food intake records were collected from 32 and 30 patients respectively, mean age 69 (SD 8) years. At breakfast, protein intake was improved from 14% of individual requirements to 22% (p<0.001) and energy intake was improved from 18% to 25% (p=0.01). Total amount of protein intake for breakfast was increased from 14 g to 20 g (p<0.002). Total daily protein intake increased from 64% to 77% (p=0.05) and total energy intake from 76% to 99% (p<0.01) of requirements.

CONCLUSION

Protein and energy intake for surgical patients at breakfast as well as total daily intake was significantly increased to meet recommended average level for minimum individually measured requirements.