Effects of correcting metabolic acidosis on muscle mass and functionality in chronic kidney disease: a systematic review and meta-analysis.

Metabolic acidosis unfavourably influences the nutritional status of patients with non-dialysis dependent chronic kidney disease (CKD) including the loss of muscle mass and functionality, but the benefits of correction are uncertain. We investigated the effects of correcting metabolic acidosis on nutritional status in patients with CKD in a systematic review and meta-analysis. A search was conducted in MEDLINE and the Cochrane Library from inception to June 2023. Study selection, bias assessment, and data extraction were independently performed by two reviewers. The Cochrane risk of bias tool was used to assess the quality of individual studies. We applied random effects meta-analysis to obtain pooled standardized mean difference (SMD) and 95% confidence intervals (CIs). We retrieved data from 12 intervention studies including 1995 patients, with a mean age of 63.7 ± 11.7 years, a mean estimated glomerular filtration rate of 29.8 ± 8.8 mL/min per 1.73 m2 , and 58% were male. Eleven studies performed an intervention with oral sodium bicarbonate compared with either placebo or with standard care and one study compared veverimer, an oral HCl-binding polymer, with placebo. The mean change in serum bicarbonate was +3.6 mEq/L in the intervention group and +0.4 mEq/L in the control group. Correcting metabolic acidosis significantly improved muscle mass assessed by mid-arm muscle circumference (SMD 0.35 [95% CI 0.16 to 0.54], P < 0.001) and functionality assessed with the sit-to-stand test (SMD -0.31 [95% CI -0.52 to 0.11], P = 0.003). We found no statistically significant effects on dietary protein intake, handgrip strength, serum albumin and prealbumin concentrations, and blood urea nitrogen. Correcting metabolic acidosis in patients with CKD improves muscle mass and physical function. Correction of metabolic acidosis should be considered as part of the nutritional care for patients with CKD.

[Influence of environmental factors and polymorphic loci rs6580502 of the SPINK1 gene, rs10273639 of the PRSS1 gene, rs213950 of the CFTR gene on the risk of developing acute alcoholic-alimentary pancreatitis].

The study of genetic and environmental factors on the risk of acute alcoholic-alimentary pancreatitis (AАAР) is especially relevant to interpret individual links of pathogenesis, to reduce the incidence by eliminating the impact of harmful factors and improve the quality of life of the population through the introduction of optimal nutrition, and a healthy lifestyle, which is especially important for carriers of risk genotypes. The aim of the research was to study the influence of environmental factors and polymorphic loci rs6580502 of the SPINK1 gene, rs10273639 of the PRSS1 gene, rs213950 of the CFTR gene on the risk of АAР. Material and methods. Blood DNA samples obtained from 547 patients with AАAР and 573 healthy individuals were used as the material for the study. The groups were comparable by sex and age. All participants were assessed qualitatively and quantitatively for risk factors, smoking and alcohol consumption, the frequency, quantity and regularity of intake of various types of foods, as well as the size and number of portions eaten. Genomic DNA was isolated by the standard phenol-chloroform extraction method, multiplex genotyping of SNPs was performed on a MALDI-TOF MassARRAY-4 genetic analyzer. Results. It was found that the T/T genotype (p=0.0012) of the rs6580502 SPINK1 was associated with an increased risk of AAAP, and the T allele (p=0.0001) and C/T and T/T genotypes (p=0.0001) of the rs10273639 PRSS1, A allele (p=0.01) and A/G and A/A genotypes (p=0.0006) of the rs213950 CFTR were associated with an decreased risk of the disease. The revealed effects of polymorphic loci of candidate genes were enhanced by the effect of alcohol consumption. The risk of AAAP was reduced by fat intake of less than 89 g per day in carriers of the A/G-A/A CFTR genotypes (rs213950), consumption of fresh vegetables and fruits of more than 27 g per day in carriers of the T/C-T/T PRSS1 genotypes (rs10273639), protein intake of more 84 g per day in carriers of T/C-T/T PRSS1 rs10273639 and A/G-A/A CFTR rs213950. The most significant models of gene-environment interactions included risk factors: deficiency in the diet of protein, fresh vegetables and fruits, smoking, and polymorphic variants of the PRSS1 (rs10273639) and SPINK (rs6580502) genes. Conclusion. In order to prevent the development of AAAP, carriers of risk genotypes of candidate genes need not only to exclude or significantly reduce alcohol consumption (in terms of volume, frequency and duration); but also carriers of the A/G-A/A CFTR genotypes (rs213950) need to balance the diet by reducing fat intake to less than 89 g per day and increasing protein intake to more than 84 g per day; carriers of the T/C-T/T PRSS1 (rs10273639) genotypes should increase their intake of fresh vegetables and fruits over 27 g/day and protein over 84 g/day.

[Controversy 1: Assessing nutritional status and sarcopenia, and calculating protein requirements. Should these be specific?] / Controversia 1. ¿Cómo realizar la valoración nutricional y de la sarcopenia, y el cálculo de requerimientos de proteínas necesarias? ¿Deben ser específicas?

Introduction: Controversy 1: Assessing nutritional status and sarcopenia, and calculating protein requirements. Should these be specific?

Introducción: Controversia 1. ¿Cómo realizar la valoración nutricional y de la sarcopenia, y el cálculo de requerimientos de proteínas necesarias? ¿Deben ser específicas?

Poor Muscle Status, Dietary Protein Intake, Exercise Levels, Quality of Life and Physical Function in Women with Metastatic Breast Cancer at Chemotherapy Commencement and during Follow-Up.

This study aimed to investigate nutritional status, body composition, dietary protein intake, handgrip strength, 6 min or 4 m walk tests, self-reported physical activity, physical function, and quality of life (QoL-EORTC-QLQc30) at commencement of chemotherapy; to detect changes over time (from commencement of chemotherapy, and after 3, 6, 12, 26 and 52 weeks) in women with metastatic breast cancer (MBC); and to investigate the relationship between nutritional variables. 'Sarcopenia' was defined as low muscle mass and strength, 'myosteatosis' as muscle fat-infiltration (CT scan). Continuous variables were analysed using paired t-tests between baseline and follow-ups. Fifteen women (54y, 95% CI [46.3;61.2]) were recruited. At baseline, malnutrition was present in 3 (20%) participants, sarcopenia in 3 (20%) and myosteatosis in 7 (54%). Thirteen (87%) participants had low protein intake; low handgrip strength was observed in 0, and low walk test distance and physical activity in four (27%) participants. Physical function and QoL were low in 10 (67%) and 9 (60%), respectively. QoL between baseline and 52 weeks decreased by 11.7 (95% CI [2.4;20.9], p = 0.025). Other variables did not significantly change over time. In this small study sample, myosteatosis, low dietary protein intake, low exercise levels and impaired quality of life and physical function are common.

Reply to the letter to the editor: Effects of adequate dietary protein with whey protein, leucine, and vitamin D supplementation on sarcopenia in older adults: An open-label, parallel-group study.

This is a response to the comment on our published article "Effects of adequate dietary protein with whey protein, leucine, and vitamin D supplementation on sarcopenia in older adults: An open-label, parallel-group study". Safer et al., questioned about the procedure and consistency of bioelectrical impedance analysis (BIA) measurement at the baseline and follow up visits. Also, they wondered whether the BIA device we used is validated in Taiwanese older adults with sarcopenia. We followed the standard protocols and the procedures were consistent at each measurement. Magnetic resonance image (MRI) and dual energy X ray absorptiometry (DXA) are gold standards for quantifying muscle mass. According to the clinical trials performed in Taiwan, the BIA device we used showed a significant correlation with MRI and DXA and is validated in older adults with sarcopenia in Taiwan. Trial registration: ClinicalTrials.gov NCT03860194.

Ingesta proteica en mujeres posmenopáusicas residentes en la comunidad y su relación con la sarcopenia / Protein intake in community-dwelling postmenopausal women and its relationship with sarcopenia

Objetivos: el envejecimiento general de la población se encuentra relacionado con el aumento de la prevalencia de la enfermedad sarcopénica, especialmente entre las mujeres mayores. Esta patología se encuentra estrechamente relacionada con la nutrición y, concretamente, con el consumo proteico en los adultos mayores. El objetivo de nuestro estudio fue evaluar la posible relación entre un bajo consumo de proteínas y una mayor prevalencia de la enfermedad sarcopénica, un peor patrón dietético y un menor rendimiento físico en mujeres posmenopáusicas residentes en la comunidad. Material y métodos: el estudio se realizó en un total de 164 mujeres mayores de 65 años, independientes, reclutadas en un centro social municipal de Valencia (Benimaclet). La presencia de sarcopenia fue evaluada utilizando el último algoritmo publicado por el EWGSOP2, y la ingesta de nutrientes a través de un registro dietético de tres días. El rendimiento físico fue evaluado a través del cuestionario iPaq-e, así como el test SPPB y el test de velocidad de la marcha de 4 metros. Resultados: la muestra total comprendió un total de 164 participantes con una edad media de ± 72 años. Un 26,2 % de la muestra presentaban una ingesta de proteínas inferior a la recomendada por la FAO/OMS. El 25,6 % de las mujeres presentaban algún estadio de sarcopenia y, en cuanto a la prevalencia de la obesidad sarcopénica, un 12,2 % de la muestra se encontró afectada por dicha enfermedad. Se encontraron relaciones significativas entre el consumo de proteína y la prevalencia de la sarcopenia (p = 0,021) y la obesidad sarcopénica (p = 0,043). Se encontraron diferencias significativas relacionadas entre la mayoría de macronutrientes y micronutrientes a estudio y el consumo proteico. No se encontró ninguna relación entre la ingesta proteica y el rendimiento físico. (AU)

Objectives: the general aging of the population is related to the increase in the prevalence of sarcopenic disease; especially among older women, this pathology is closely related to nutrition and specifically to protein consumption in older adults. The aim of our study was to evaluate the possible relationship between a low protein intake and a higher prevalence of sarcopenic disease, a worse dietary pattern, and lower physical performance in postmenopausal women living in the community. Material and methods: the study was carried out in a total of 164 independent women over 65 years of age, recruited from a municipal social center in Valencia (Benimaclet). The presence of sarcopenic pathology was evaluated using the latest algorithm published by EWGSOP2, and the intake of nutrients through a three-day dietary record. Physical performance was evaluated through the iPaq-e questionnaire, as well as the SPPB test and the 4-meter gait speed test. Results: the total sample comprised 164 women with a mean age of ± 72 years; 26.2 % of the sample had a protein intake lower than recommended by the FAO/WHO; 25.6 % of the women presented some stage of sarcopenia; regarding the prevalence of sarcopenic obesity, 12.2 % of the sample was affected by this disease. Significant relationships were found between protein consumption and the prevalence of sarcopenia (p = 0.021) and sarcopenic obesity (p = 0.043). Significant related differences were found between the majority of macronutrients and micronutrients under study and protein consumption. No relationship was found between protein intake and physical performance. (AU)

[Protein intake in community-dwelling postmenopausal women and its relationship with sarcopenia]. / Ingesta proteica en mujeres posmenopáusicas residentes en la comunidad y su relación con la sarcopenia.

INTRODUCTION: Objectives: the general aging of the population is related to the increase in the prevalence of sarcopenic disease; especially among older women, this pathology is closely related to nutrition and specifically to protein consumption in older adults. The aim of our study was to evaluate the possible relationship between a low protein intake and a higher prevalence of sarcopenic disease, a worse dietary pattern, and lower physical performance in postmenopausal women living in the community. Material and methods: the study was carried out in a total of 164 independent women over 65 years of age, recruited from a municipal social center in Valencia (Benimaclet). The presence of sarcopenic pathology was evaluated using the latest algorithm published by EWGSOP2, and the intake of nutrients through a three-day dietary record. Physical performance was evaluated through the iPaq-e questionnaire, as well as the SPPB test and the 4-meter gait speed test. Results: the total sample comprised 164 women with a mean age of ± 72 years; 26.2 % of the sample had a protein intake lower than recommended by the FAO/WHO; 25.6 % of the women presented some stage of sarcopenia; regarding the prevalence of sarcopenic obesity, 12.2 % of the sample was affected by this disease. Significant relationships were found between protein consumption and the prevalence of sarcopenia (p = 0.021) and sarcopenic obesity (p = 0.043). Significant related differences were found between the majority of macronutrients and micronutrients under study and protein consumption. No relationship was found between protein intake and physical performance. Conclusions: protein consumption in most of the women studied (73.8 %) was higher than the daily recommendations established by the FAO/WHO. There was a significant relationship between the prevalence of sarcopenia and sarcopenic obesity, and low protein intake. Higher protein intake was associated with a higher energy intake pattern. No relationship was found between protein intake and physical performance of the participants.

INTRODUCCIÓN: Objetivos: el envejecimiento general de la población se encuentra relacionado con el aumento de la prevalencia de la enfermedad sarcopénica, especialmente entre las mujeres mayores. Esta patología se encuentra estrechamente relacionada con la nutrición y, concretamente, con el consumo proteico en los adultos mayores. El objetivo de nuestro estudio fue evaluar la posible relación entre un bajo consumo de proteínas y una mayor prevalencia de la enfermedad sarcopénica, un peor patrón dietético y un menor rendimiento físico en mujeres posmenopáusicas residentes en la comunidad. Material y métodos: el estudio se realizó en un total de 164 mujeres mayores de 65 años, independientes, reclutadas en un centro social municipal de Valencia (Benimaclet). La presencia de sarcopenia fue evaluada utilizando el último algoritmo publicado por el EWGSOP2, y la ingesta de nutrientes a través de un registro dietético de tres días. El rendimiento físico fue evaluado a través del cuestionario iPaq-e, así como el test SPPB y el test de velocidad de la marcha de 4 metros. Resultados: la muestra total comprendió un total de 164 participantes con una edad media de ± 72 años. Un 26,2 % de la muestra presentaban una ingesta de proteínas inferior a la recomendada por la FAO/OMS. El 25,6 % de las mujeres presentaban algún estadio de sarcopenia y, en cuanto a la prevalencia de la obesidad sarcopénica, un 12,2 % de la muestra se encontró afectada por dicha enfermedad. Se encontraron relaciones significativas entre el consumo de proteína y la prevalencia de la sarcopenia (p = 0,021) y la obesidad sarcopénica (p = 0,043). Se encontraron diferencias significativas relacionadas entre la mayoría de macronutrientes y micronutrientes a estudio y el consumo proteico. No se encontró ninguna relación entre la ingesta proteica y el rendimiento físico. Conclusiones: el consumo de proteínas en la mayoría de las mujeres estudiadas (73,8 %) fue superior a las recomendaciones diarias establecidas por la FAO/OMS. Existió una relación significativa entre la prevalencia de la sarcopenia y de la obesidad sarcopénica y un consumo bajo de proteínas. Un mayor consumo de proteínas se asoció con un patrón de ingesta energética superior. No se encontró relación alguna entre la ingesta proteica y el rendimiento físico de las participantes.

Effect of dietary sources of calcium and protein on hip fractures and falls in older adults in residential care: cluster randomised controlled trial.

OBJECTIVE: To assess the antifracture efficacy and safety of a nutritional intervention in institutionalised older adults replete in vitamin D but with mean intakes of 600 mg/day calcium and <1 g/kg body weight protein/day. DESIGN: Two year cluster randomised controlled trial. SETTING: 60 accredited residential aged care facilities in Australia housing predominantly ambulant residents. PARTICIPANTS: 7195 permanent residents (4920 (68%) female; mean age 86.0 (SD 8.2) years). INTERVENTION: Facilities were stratified by location and organisation, with 30 facilities randomised to provide residents with additional milk, yoghurt, and cheese that contained 562 (166) mg/day calcium and 12 (6) g/day protein achieving a total intake of 1142 (353) mg calcium/day and 69 (15) g/day protein (1.1 g/kg body weight). The 30 control facilities maintained their usual menus, with residents consuming 700 (247) mg/day calcium and 58 (14) g/day protein (0.9 g/kg body weight). MAIN OUTCOME MEASURES: Group differences in incidence of fractures, falls, and all cause mortality. RESULTS: Data from 27 intervention facilities and 29 control facilities were analysed. A total of 324 fractures (135 hip fractures), 4302 falls, and 1974 deaths were observed. The intervention was associated with risk reductions of 33% for all fractures (121 v 203; hazard ratio 0.67, 95% confidence interval 0.48 to 0.93; P=0.02), 46% for hip fractures (42 v 93; 0.54, 0.35 to 0.83; P=0.005), and 11% for falls (1879 v 2423; 0.89, 0.78 to 0.98; P=0.04). The risk reduction for hip fractures and falls achieved significance at five months (P=0.02) and three months (P=0.004), respectively. Mortality was unchanged (900 v 1074; hazard ratio 1.01, 0.43 to 3.08). CONCLUSIONS: Improving calcium and protein intakes by using dairy foods is a readily accessible intervention that reduces the risk of falls and fractures commonly occurring in aged care residents. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12613000228785.

The effect of higher versus lower protein delivery in critically ill patients: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: The optimal protein dose in critical illness is unknown. We aim to conduct a systematic review of randomized controlled trials (RCTs) to compare the effect of higher versus lower protein delivery (with similar energy delivery between groups) on clinical and patient-centered outcomes in critically ill patients. METHODS: We searched MEDLINE, EMBASE, CENTRAL and CINAHL from database inception through April 1, 2021.We included RCTs of (1) adult (age ≥ 18) critically ill patients that (2) compared higher vs lower protein with (3) similar energy intake between groups, and (4) reported clinical and/or patient-centered outcomes. We excluded studies on immunonutrition. Two authors screened and conducted quality assessment independently and in duplicate. Random-effect meta-analyses were conducted to estimate the pooled risk ratio (dichotomized outcomes) or mean difference (continuous outcomes). RESULTS: Nineteen RCTs were included (n = 1731). Sixteen studies used primarily the enteral route to deliver protein. Intervention was started within 72 h of ICU admission in sixteen studies. The intervention lasted between 3 and 28 days. In 11 studies that reported weight-based nutrition delivery, the pooled mean protein and energy received in higher and lower protein groups were 1.31 ± 0.48 vs 0.90 ± 0.30 g/kg and 19.9 ± 6.9 versus 20.1 ± 7.1 kcal/kg, respectively. Higher vs lower protein did not significantly affect overall mortality [risk ratio 0.91, 95% confidence interval (CI) 0.75-1.10, p = 0.34] or other clinical or patient-centered outcomes. In 5 small studies, higher protein significantly attenuated muscle loss (MD -3.44% per week, 95% CI -4.99 to -1.90; p < 0.0001). CONCLUSION: In critically ill patients, a higher daily protein delivery was not associated with any improvement in clinical or patient-centered outcomes. Larger, and more definitive RCTs are needed to confirm the effect of muscle loss attenuation associated with higher protein delivery. PROSPERO registration number: CRD42021237530.

The 2020 Updated KDOQI Clinical Practice Guidelines for Nutrition in Chronic Kidney Disease.

Over the last 2 decades, there has been a great accumulation of new evidence regarding the management of nutritional and metabolic aspects of kidney disease. The 2020 update to the KDOQI Clinical Practice Guideline for Nutrition in CKD provides a comprehensive up-to-date information on the understanding and care of patients with CKD. It provides updated information on nutritional aspects of kidney disease for the practicing clinician and allied health-care workers. The current manuscript provides an overview of the updated guideline statements on major subjects including nutritional assessment, dietary protein and energy intake, nutritional supplementation, micronutrients, and electrolytes. The guidelines are focused on dietary management rather than all possible nutritional interventions.

The effect of vitamin D plus protein supplementation on sarcopenia: A systematic review and meta-analysis of randomized controlled trials.

PURPOSE: The exact effect of vitamin D supplementation, either as monotherapy or in combination with protein, on musculoskeletal health in patients with sarcopenia is currently unknown. This study aimed to determine the effect of vitamin D alone or with protein supplementation on muscle strength, mass, and performance in this population. METHODS: A comprehensive search was conducted in Medline, Cochrane Central and Scopus databases, up to March 31st, 2020. Data were expressed as standardized mean difference (SMD) with 95 % confidence intervals (CI). I2 index was employed for heterogeneity. RESULTS: The initial search identified 1164 studies, eight of which met the eligibility criteria for qualitative and quantitative analysis, yielding a total of 776 patients. Vitamin D (100-1600 IU/day) plus protein (10-44 g/day) supplementation exhibited a beneficial effect on muscle strength, as demonstrated by an improvement in handgrip strength (SMD 0.38 ± 0.07, 95 % CI 0.18-0.47, p = 0.04; I2 76.2 %) and a decrease in the sit-to-stand time (SMD 0.25 ± 0.09, 95 % CI 0.06-0.43, p = 0.007; I2 0%) compared with placebo. However, the effect on muscle mass, assessed by skeletal muscle index, was marginally non-significant (SMD 0.25 ± 0.13, 95 % CI -0.006-0.51, p = 0.05; I2 0%). No effect on appendicular skeletal muscle mass or muscle performance (assessed by walking speed) was observed with vitamin D plus protein. CONCLUSIONS: Vitamin D supplementation, combined with protein, improves muscle strength in patients with sarcopenia, but has no effect on muscle mass or performance.

High protein prescription in methylmalonic and propionic acidemia patients and its negative association with long-term outcome.

BACKGROUND AND OBJECTIVE: Methylmalonic acidemia (MMA) and propionic acidemia (PA) are inborn errors of metabolism. While survival of MMA and PA patients has improved in recent decades, long-term outcome is still unsatisfactory. A protein restricted diet is the mainstay for treatment. Additional amino acid mixtures (AAM) can be prescribed if natural protein is insufficient. It is unknown if dietary treatment can have an impact on outcome. DESIGN: We performed a nationwide retrospective cohort study and evaluated both longitudinal dietary treatment and clinical course of Dutch MMA and PA patients. Protein prescription was compared to the recommended daily allowances (RDA); the safe level of protein intake as provided by the World Health Organization. The association of longitudinal dietary treatment with long-term outcome was evaluated. RESULTS: The cohort included 76 patients with a median retrospective follow-up period of 15 years (min-max: 0-48 years) and a total of 1063 patient years on a protein restricted diet. Natural protein prescription exceeded the RDA in 37% (470/1287) of all prescriptions and due to AAM prescription, the total protein prescription exceeded RDA in 84% (1070/1277). Higher protein prescriptions were associated with adverse outcomes in severely affected patients. In PA early onset patients a higher natural protein prescription was associated with more frequent AMD. In MMA vitamin B12 unresponsive patients, both a higher total protein prescription and AAM protein prescription were associated with more mitochondrial complications. A higher AAM protein prescription was associated with an increased frequency of cognitive impairment in the entire. CONCLUSION: Protein intake in excess of recommendations is frequent and is associated with poor outcome.

Pre-Digested Protein Enteral Nutritional Supplementation Enhances Recovery of CD4+ T Cells and Repair of Intestinal Barrier in HIV-Infected Immunological Non-Responders.

AIDS patients with immune non-response are prone to malnutrition, intestinal barrier damage, thus aggravating chronic immune activation and inflammation. However, nutritional interventions targeting malnutrition may be beneficial to restore immune function, improve clinical outcomes, and reduce mortality remains largely unclear. This work aimed to evaluate the efficacy of a nutritional supplement in HIV-infected immune non-responders (INRs). The subjects received oral supplementation of a pre-digested protein nutrition formula for three months. We show that the CD4+ T and CD8+ T cell counts were significantly increased after supplementation of the pre-digested enteral nutritional supplement. Among all pro-inflammatory cytokines in the serum, only IL-1ß level was significantly decreased, while TNF-ß was significantly increased (P < 0.05). The levels of intestinal mucosal damage markers, diamine oxidase (DAO), D-lactic acid (D-lactate), and lipopolysaccharide (LPS), decreased significantly (P < 0.05) after the nutritional intervention. Moreover, at month 3 after the intervention, the body weight, body mass index, albumin, and hemoglobin of all subjects were significantly increased (P < 0.05). The correlation analysis demonstrated a significantly negative correlation of CD4+ T cell count with levels of DAO (r = -0.343, P = 0.004), D-lactate (r = -0.250, P = 0.037), respectively, and a significantly positive correlation of IL-1ß level with levels of DAO (r = 0.445, P < 0.001), D-lactate (r = 0.523, P < 0.001), and LPS (r = 0.622, P < 0.001). We conclude that the pre-digested enteral nutrition supplement is effective for HIV-infected INRs.

Fighting Sarcopenia in Ageing European Adults: The Importance of the Amount and Source of Dietary Proteins.

While an adequate protein intake is important for the maintenance of muscle mass during ageing, the amount and source of protein necessary for optimal prevention of sarcopenia remains to be determined. The present study aimed to investigate the influence of the amount and source of dietary proteins on sarcopenia risk in a cohort of 65-79-year-old European adults within the frame of the NU-AGE study. A total of 986 participants were included in the analysis. Skeletal muscle index (SMI), assessed by dual-energy X-ray absorptiometry (DXA), and handgrip strength (HG) were employed to create a continuous sex-specific sarcopenia risk score (SRS). Total amount together with animal- and plant-derived sources of proteins were obtained from a 7-day food record. Differences in SRS were analysed across groups of total protein intake (<0.8 g/body weight (BW); 0.8-<1.0 g/BW; 1.0-<1.2 g/BW; and ≥1.2 g/BW). The association between SRS and the different sources of protein was assessed using isocaloric substitution models adjusted by demographic, medical, and lifestyle factors. A significant linear dose-response relationship was observed, with a lower SRS linked to higher protein intakes. Based on the isocaloric substitution modelling, a reduced SRS was observed when increasing plant protein to the detriment of animal protein, while holding total protein intake constant. Further, this result remained significant after stratifying the analysis by adherence to different levels of protein intake. Our findings suggest that older adults may benefit from increasing protein intakes above current recommendations. Besides total amount, protein source should be considered when promoting health dietary habits in older adults for the prevention of sarcopenia.

Protein, amino acids and obesity treatment.

Dietary proteins have been used for years to treat obesity. Body weight loss is beneficial when it concerns fat mass, but loss of fat free mass - especially muscle might be detrimental. This occurs because protein breakdown predominates over synthesis, thus administering anabolic dietary compounds like proteins might counter fat free mass loss while allowing for fat mass loss.Indeed, varying the quantity of proteins will decrease muscle anabolic response and increase hyperphagia in rodents fed a low protein diet; but it will favor lean mass maintenance and promote satiety, in certain age groups of humans fed a high protein diet. Beyond protein quantity, protein source is an important metabolic regulator: whey protein and plant based diets exercize favorable effects on the risk of developing obesity, body composition, metabolic parameters or fat free mass preservation of obese patients. Specific amino-acids like branched chain amino acids (BCAA), methionine, tryptophan and its metabolites, and glutamate can also positively influence parameters and complications of obesity especially in rodent models, with less studies translating this in humans.Tuning the quality and quantity of proteins or even specific amino-acids can thus be seen as a potential therapeutic intervention on the body composition, metabolic syndrome parameters and appetite regulation of obese patients. Since these effects vary across age groups and much of the data comes from murine models, long-term prospective studies modulating proteins and amino acids in the human diet are needed.

Effect of low-protein intake on all-cause mortality in subjects with an estimated glomerular filtration rate higher than 60 mL/min/1.73 m2 with or without albuminuria.

BACKGROUND: We aimed to investigate the effect of a low-protein intake on all-cause mortality in subjects with an estimated glomerular filtration rate (eGFR) ≧60 mL/min/1.73 m2 with or without albuminuria using data from the National Health and Nutrition Examination Survey (NHANES). METHODS: We analysed participants in the NHANES from 2003 to 2010. We excluded participants with an eGFR less than 60 mL/min/1.73 m2 from the analyses. Low-protein intake was defined as a protein intake of less than 0.8 g/kg/day. The Healthy Eating Index 2010 was used to assess diet quality. The vital status of all participants in the NHANES was determined by linking to the National Death Index through the end of 2011. The hazard ratios (HRs) for the association of low-protein intake and mortality were determined using weighted Cox proportional hazards regression models. RESULTS: A total of 7730 participants were included in the analyses. After a median follow up of 4.7 years, 462 participants died. A low-protein intake was associated with a higher risk of mortality (HRs 1.394, 95% CI 1.121-1.734, P = .004) with adjustment for diet quality and relevant risk factors. The higher risk of mortality associated with a low-protein intake was consistent in subjects with or without albuminuria (P interaction .280). CONCLUSION: A protein intake of less than 0.8 g/kg/day was associated with a higher risk of mortality in subjects with an eGFR ≧60 mL/min/1.73 m2 , irrespective of whether they had albuminuria.

Association between Dietary Protein Intake and Cognitive Function in Adults Aged 60 Years and Older.

OBJECTIVES: The aim of this study was to examine the association of dietary protein intake and protein sources with cognitive function in population aged 60 years and older. DESIGN: Cross-sectional study. SETTING: The National Health and Nutrition Examination Survey (NHANES) 2011-2014. PARTICIPANTS: Non-institutionalized US adults aged 60 years and older. MEASUREMENTS: Cognitive functions were assessed by a series of cognitive tests. Dietary protein intake was assessed by two 24-hour dietary recall interviews. Linear regression analyses were used to assess the associations between quartiles of dietary protein intake and cognitive function. RESULTS: Protein intake was positively associated with cognitive function. In full-adjusted model, the significant association between dietary protein intake and Recall Test score was observed (quartile (Q) 2 versus Q1, ß=0.24, 95%CI: 0.01 to 0.47); the association between protein intake and Animal Fluency test was significant (Q2 versus Q1, ß=1.40, 95%CI: 0.51 to 2.29; Q4 versus Q1, ß=1.42, 95%CI: 0.37 to 2.48); the positive associations with DSST score and Composite z-score were observed both in Q2 versus Q1 and Q3 versus Q1 of protein intake. Protein intake from total animal, total meat, eggs and legumes were associated with a better performance on certain cognitive tests. However, an adverse association between higher protein intake from milk and milk products and cognitive function was observed. CONCLUSIONS: We found the positive associations of dietary protein intake and protein intake from total animal, total meat, eggs and legumes with cognitive function in adults aged 60 years and older, while higher milk and milk products were negatively associated with cognitive function.

Protein Nutrition in Autism.

Autism is a developmental disorder that affects communication and behavior. Although autism can be diagnosed at any age, it is said to be a "developmental disorder" because symptoms generally appear in the first 2 years of life. The primary cause of autism is still not clear and therapy is currently restricted to controlling behavioral abnormalities. However, emerging studies have shown a link between mitochondrial dysfunction and autism. Dietary supplements that promote mitochondrial biogenesis and inhibit the production of oxidative stress have been used to treat autism patients. Dietary adjustments in treating autism is a novel approach to suppress autistic symptoms. Supplementation with antioxidants has been found to not only inhibit cognitive decline but also improve behavioral symptoms in autism. Dietary supplements fortified with vitamins should only be given under the supervision of a physician. A wide range of nutraceuticals are under clinical trials to understand whether they physiologically target mitochondrial pathways and improve the quality of life in autism.