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Current Nutrition Reports Dec 2019The purpose of this review is to provide background on the present literature regarding the utility and effectiveness of protein supplements, including protein source... (Review)
Review
PURPOSE OF REVIEW
The purpose of this review is to provide background on the present literature regarding the utility and effectiveness of protein supplements, including protein source and nutrient timing.
RECENT FINDINGS
In the setting of adequate dietary protein consumption, research suggests some benefit particularly in sport or exercise activities. Protein supplements command a multi-billion-dollar market with prevalent use in sports. Many individuals, including athletes, do not consume optimal dietary protein on a daily basis. High-protein diets are remarkably safe in healthy subjects, especially in the short term. Some objective outcomes are physiologic and may not translate to clinically relevant outcomes. Athletes should, however, consider long-term implications when consuming high quantities of protein in dietary or supplement form.
Topics: Athletes; Athletic Performance; Body Composition; Databases, Factual; Dietary Proteins; Dietary Supplements; Energy Metabolism; Humans; Nutrients; Physical Education and Training; Sports
PubMed: 31713177
DOI: 10.1007/s13668-019-00293-1 -
Food Chemistry Jul 2022Keratin derived protein (KDP) was extracted from sheep wool using high pressure microwave technology and food acids and investigated for its potential as a novel dietary...
Keratin derived protein (KDP) was extracted from sheep wool using high pressure microwave technology and food acids and investigated for its potential as a novel dietary protein. The proximate composition, amino acid profile, element profile, in vitro cytotoxicity and digestibility of KDP were evaluated. Nutritive effects of KDP at 50% dietary supplementation were compared with a casein-based diet in a growing rat model for 95 days. Results indicate KDP to be rich in protein (86%), amino acid cysteine (8.8 g/100 g) and element selenium (0.29 μg/g). KDP was non-cytotoxic in vitro at ≤ 2 mg/mL concentration. There were no differences in the rat's weight gain compared to the control group (P > 0.05). Overall, the inclusion of the KDP in the diet was an effective substitute for casein protein at 50% and KDP has the potential to be used in the food industry as a novel dietary protein, free of fat and carbohydrate.
Topics: Amino Acids; Animal Feed; Animals; Caseins; Diet; Dietary Proteins; Keratins; Nutritive Value; Rats; Sheep; Wool
PubMed: 35183955
DOI: 10.1016/j.foodchem.2022.132436 -
Nutrients Aug 2020High protein intake can increase glomerular filtration rate (GFR) in response to excretory overload, which may exacerbate the progression of kidney disease. However, the...
High protein intake can increase glomerular filtration rate (GFR) in response to excretory overload, which may exacerbate the progression of kidney disease. However, the direct association between glomerular hemodynamic response at the single-nephron level and dietary protein intake has not been fully elucidated in humans. In the present study, we evaluated nutritional indices associated with single-nephron GFR (SNGFR) calculated based on corrected creatinine clearance (SNGFR). We retrospectively identified 43 living kidney donors who underwent enhanced computed tomography and kidney biopsy at the time of donation at Jikei University Hospital in Tokyo from 2007 to 2018. Total nephron number was estimated with imaging-derived cortical volume and morphometry-derived glomerular density. SNGFR was calculated by dividing the corrected creatinine clearance by the number of non-sclerosed glomeruli (Nglom). The mean (± standard deviation) Nglom/kidney and SNGFR were 685,000 ± 242,000 and 61.0 ± 23.9 nL/min, respectively. SNGFR was directly associated with estimated protein intake/ideal body weight ( = 0.005) but not with body mass index, mean arterial pressure, albumin, or sodium intake. These findings indicate that greater protein intake may increase SNGFR and lead to glomerular hyperfiltration.
Topics: Cohort Studies; Dietary Proteins; Female; Glomerular Filtration Rate; Humans; Kidney; Living Donors; Male; Middle Aged; Nephrons; Retrospective Studies; Tokyo; Tomography, X-Ray Computed
PubMed: 32842498
DOI: 10.3390/nu12092549 -
Frontiers in Neuroendocrinology Oct 2018Restriction of dietary protein intake increases food intake and energy expenditure, reduces growth, and alters amino acid, lipid, and glucose metabolism. While these... (Review)
Review
Restriction of dietary protein intake increases food intake and energy expenditure, reduces growth, and alters amino acid, lipid, and glucose metabolism. While these responses suggest that animals 'sense' variations in amino acid consumption, the basic physiological mechanism mediating the adaptive response to protein restriction has been largely undescribed. In this review we make the case that the liver-derived metabolic hormone FGF21 is the key signal which communicates and coordinates the homeostatic response to dietary protein restriction. Support for this model centers on the evidence that FGF21 is induced by the restriction of dietary protein or amino acid intake and is required for adaptive changes in metabolism and behavior. FGF21 occupies a unique endocrine niche, being induced when energy intake is adequate but protein and carbohydrate are imbalanced. Collectively, the evidence thus suggests that FGF21 is the first known endocrine signal of dietary protein restriction.
Topics: Animals; Diet, Protein-Restricted; Dietary Carbohydrates; Dietary Proteins; Feeding Behavior; Fibroblast Growth Factors; Homeostasis
PubMed: 29890191
DOI: 10.1016/j.yfrne.2018.06.002 -
Critical Reviews in Food Science and... 2021Dietary proteins and phenolic compounds are commonly co-existing components that readily interact with each other to yield complexes in a wide range of food systems. The... (Review)
Review
Dietary proteins and phenolic compounds are commonly co-existing components that readily interact with each other to yield complexes in a wide range of food systems. The formed complexes play a critical role in the physiochemical characteristics of both reacting molecules, thereby impacting nutritional and quality profiles of related products. In this review, we provided the most updated knowledge on dietary protein-phenolic interactions related with food science and human nutrition, including their mechanisms of complexation, analytical technologies, and alterations in the functionality and nutraceutical properties of both reacting partners. Their potential applications in the industries regarding stability during food processing and storage, impacts on product quality, and fabrication of novel delivery systems for liable bioactives were also discussed. The interactions between dietary proteins and phenolics, either via non-covalent or covalent processes, are ubiquitous in food systems and are closely associated with chemical structures of both compounds and the surrounding conditions, mainly temperature, pH, and the presence of phenolic oxidases. Albeit in different ways, such intermolecular associations induced changes in protein conformational structures, which subsequently impacted their techno-functional properties, digestibility, and allergenic potentials; in turn, the bioaccessibility/bioavailability and health-protecting features of interacted phenolics were modified to various extents, as noticed by in vitro and in vivo evidence. Largely depending on the interaction molecules and preparation steps, those influences can be either favorable or unfavorable in different systems and therefore can be tailored to develop food products and nutraceuticals with maximized functionality and quality attributes.
Topics: Antioxidants; Dietary Proteins; Dietary Supplements; Food Handling; Humans; Phenols
PubMed: 32814438
DOI: 10.1080/10408398.2020.1803199 -
The American Journal of Clinical... Jul 2015
Topics: Dietary Proteins; Female; Humans; Kidney; Male; Maternal Nutritional Physiological Phenomena; Pregnancy; Pregnancy Trimester, First
PubMed: 26063690
DOI: 10.3945/ajcn.115.112672 -
Current Opinion in Clinical Nutrition... Jan 2021In this review, the latest evidence on the influence of dietary protein and plasma amino acids in the pathogenesis of nonalcoholic fatty liver disease (NAFLD) is... (Review)
Review
PURPOSE OF REVIEW
In this review, the latest evidence on the influence of dietary protein and plasma amino acids in the pathogenesis of nonalcoholic fatty liver disease (NAFLD) is discussed.
RECENT FINDINGS
Increasing protein consumption during weight loss and maintenance may help reduce liver fat content. Conversely, high protein intake characteristic of the unhealthy Western diet is associated with increased NAFLD prevalence and severity. Plasma concentration of several amino acids, including branched-chain (BCAA) and aromatic amino acids (AAA), is altered in NAFLD. Excess amino acid availability contributes to intrahepatic fat accumulation and may reflect poor dietary habits and dysregulation of amino acid metabolic processing in both liver and peripheral tissues. Specific amino acid patterns, characterized by increased BCAA, AAA, alanine, glutamate, lysine levels, and decreased glycine and serine levels, may be used for early detection of NAFLD and noninvasive assessment of its histological severity.
SUMMARY
Mechanistic studies in NAFLD have been mostly focused on carbohydrate and fat metabolism, while little is known about the influence of protein and amino acids. Moreover, intervention and observational studies on the relation between protein intake and NAFLD yielded conflicting results. Filling the current knowledge gaps would help define the optimal diet composition for NAFLD prevention and management. Furthermore, metabolomics studies may provide insight into the pathogenesis of NAFLD, identify useful diagnostic and prognostic biomarkers, and unravel novel pharmacological targets and treatment options.
Topics: Amino Acids; Dietary Proteins; Humans; Lipid Metabolism; Liver; Non-alcoholic Fatty Liver Disease
PubMed: 33060460
DOI: 10.1097/MCO.0000000000000706 -
Current Protein & Peptide Science 2019As a major component of biologically active compounds in the body, proteins contribute to the synthesis of body tissues for the renewal and growth of the body. The high... (Review)
Review
As a major component of biologically active compounds in the body, proteins contribute to the synthesis of body tissues for the renewal and growth of the body. The high level of dietary protein and the imbalance of amino acid (AA) composition in mammals result in metabolic disorders, inefficient utilization of protein resources and increased nitrogen excretion. Fortunately, nutritional interventions can be an effective way of attenuating the nitrogen excretion and increasing protein utilization, which include, but are not limited to, formulating the AA balance and protein-restricted diet supplementing with essential AAs, and adding probiotics in the diet. This review highlights recent advances in the turnover of dietary proteins and mammal's metabolism for health, in order to improve protein bioavailability through nutritional approach.
Topics: Animals; Biological Availability; Dietary Proteins; Humans; Nutrients
PubMed: 30678625
DOI: 10.2174/1389203720666190125111235 -
Critical Reviews in Food Science and... Nov 2017Protein oxidation has become a topic of great scientific interest in the field of food science and nutrition. Food proteins are known to be preferential targets of... (Review)
Review
Protein oxidation has become a topic of great scientific interest in the field of food science and nutrition. Food proteins are known to be preferential targets of radical species, and protein oxidation has relevant consequences on protein functionality and food quality. Current trends in this field call attention to the nutritional and health dimensions of oxidized foods. Both lipid and protein oxidation products are accumulated in food during processing and storage and also upon food intake during the subsequent digestion phases. The gastrointestinal tract and internal organs are exposed to the cytotoxic and mutagenic potential of these species. While the molecular basis of the pathogenesis of particular dietary lipid oxidation products is well known, the impact of dietary oxidized proteins on human health has been largely ignored. The well-established association between in vivo protein oxidation and aging and age-related diseases urges scientists to investigate the contribution of dietary protein oxidation to particular pathological conditions. Recent reports indicate the involvement of dietary protein oxidation species on particular health disorders, which emphasizes the link between dietary and in vivo protein oxidation.
Topics: Antioxidants; Diet; Dietary Proteins; Food Quality; Humans; Oxidation-Reduction
PubMed: 27128327
DOI: 10.1080/10408398.2016.1165182 -
Scientific Reports Mar 2015It is still debate of the relationship between the dietary protein consumption and risk of fracture. We searched Medline and Embase to assess the effects of dietary... (Meta-Analysis)
Meta-Analysis Review
It is still debate of the relationship between the dietary protein consumption and risk of fracture. We searched Medline and Embase to assess the effects of dietary protein consumption on risk of fracture. Twelve prospective cohort studies with 407,104 participants were included, higher total protein consumption may be decrease 11% risk of hip fractures, with adj. RR of 0.89 (0.82, 0.97), no significant difference was found for total protein and risk of all fractures and limb fracture; for animal protein consumption and risk of all fractures and hip fracture, with adj.RR of 0.79 (032, 1.96) and 1.04 (0.70, 1.54); for vegetable protein consumption and risk of all fractures, hip fracture and limb fractures with adj.RR of 0.77 (0.52, 1.12), 1.00 (0.53, 1.91), and 0.94 (0.40, 2.22), the subgroup of vegetable protein consumption and risk of all fractures of postmenopausal women with adj.RR of 0.78(0.52,1.16). Dose-response meta-analysis the relationship of total/animal/vegetable protein and hip fracture was consistent to the results of forest plot, the line of total protein and hip fracture was below the Y = 1.0 line. This meta-analysis showed that total dietary protein consumption may be decrease the risk of hip fracture, but not for animal or vegetable protein.
Topics: Animals; Cohort Studies; Diet; Dietary Proteins; Fractures, Bone; Humans; Odds Ratio; Prospective Studies; Publication Bias; Risk
PubMed: 25779888
DOI: 10.1038/srep09151