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Annals of the New York Academy of... Mar 1993
Review
Topics: Animals; Arginine; Arteriosclerosis; Caseins; Dietary Proteins; Lysine; Rabbits
PubMed: 8489130
DOI: 10.1111/j.1749-6632.1993.tb38733.x -
Current Opinion in Clinical Nutrition... Jul 2006Despite the proven efficacy of the established high-carbohydrate diets for treatment and prevention of obesity and type 2 diabetes, alternative diets including... (Review)
Review
PURPOSE OF REVIEW
Despite the proven efficacy of the established high-carbohydrate diets for treatment and prevention of obesity and type 2 diabetes, alternative diets including high-protein, high-fat, low-carbohydrate diets have become increasingly popular. The purpose of this review is to discuss potential effects of increased protein intake on glucose metabolism and body weight.
RECENT FINDINGS
Recent intervention trials revealed that, in the short-term, the intake of proteins at the expense of carbohydrates increases satiety and thereby lowers intake of calories. High protein intake augments prandial insulin secretion and might thereby improve glycaemic control in type 2 diabetic patients. On the other hand, epidemiological studies suggest that chronic high dietary protein intake is associated with increased incidence of type 2 diabetes. Furthermore, a short-term increase in plasma amino acid concentrations has been shown to directly induce insulin resistance in skeletal muscle and stimulate endogenous glucose production.
SUMMARY
Dietary proteins and amino acids are potent modulators of glucose metabolism and might also affect satiety and energy intake. However, due to the lack of well-controlled long-term studies the optimal macronutrient composition for treatment and prevention of obesity and type 2 diabetes is not known.
Topics: Blood Glucose; Dietary Proteins; Energy Intake; Energy Metabolism; Homeostasis; Humans; Obesity; Satiation
PubMed: 16778578
DOI: 10.1097/01.mco.0000232909.84483.a9 -
The Journal of Nutrition Jan 1990
Review
Topics: Adult; Calcium; Dietary Proteins; Female; Humans; Kidney; Male; Phosphorus
PubMed: 2406396
DOI: 10.1093/jn/120.1.134 -
International Journal of Sport Nutrition Dec 1998This paper reviews the factors (exercise intensity, carbohydrate availability, exercise type, energy balance, gender, exercise training, age, and timing of nutrient... (Review)
Review
This paper reviews the factors (exercise intensity, carbohydrate availability, exercise type, energy balance, gender, exercise training, age, and timing of nutrient intake or subsequent exercise sessions) thought to influence protein need. Although there remains some debate, recent evidence suggests that dietary protein need increases with rigorous physical exercise. Those involved in strength training might need to consume as much as 1.6 to 1.7 g protein x kg(-1) x day(-1) (approximately twice the current RDA) while those undergoing endurance training might need about 1.2 to 1.6 g x kg(-1) x day(-1) (approximately 1.5 times the current RDA). Future longitudinal studies are needed to confirm these recommendations and asses whether these protein intakes can enhance exercise performance. Despite the frequently expressed concern about adverse effects of high protein intake, there is no evidence that protein intakes in the range suggested will have adverse effects in healthy individuals.
Topics: Dietary Proteins; Energy Intake; Exercise; Female; Humans; Male; Muscle, Skeletal; Nutritional Requirements; Sex Factors
PubMed: 9841962
DOI: 10.1123/ijsn.8.4.426 -
Rapid Communications in Mass... Jun 2021Ecologists increasingly determine the δ N values of amino acids (AA) in animal tissue; "source" AA typically exhibit minor variation between diet and consumer, while... (Comparative Study)
Comparative Study
RATIONALE
Ecologists increasingly determine the δ N values of amino acids (AA) in animal tissue; "source" AA typically exhibit minor variation between diet and consumer, while "trophic" AA have increased δ N values in consumers. Thus, trophic-source δ N offsets (i.e., Δ N ) reflect trophic position in a food web. However, even minor variations in δ N values may influence the magnitude of offset that represents a trophic step, known as the trophic discrimination factor (i.e., TDF ). Diet digestibility and protein content can influence the δ N values of bulk animal tissue, but the effects of these factors on AA Δ N and TDF in mammals are unknown.
METHODS
We fed captive mice (Mus musculus) either (A) a low-fat, high-fiber diet with low, intermediate, or high protein; or (B) a high-fat, low-fiber diet with low or intermediate protein. Mouse muscle and dietary protein were analyzed for bulk tissue δ N using elemental analyzer-isotope ratio mass spectrometry (EA-IRMS), and were also hydrolyzed into free AA that were analyzed for δ N using gas chromatography-combustion-IRMS.
RESULTS
As dietary protein increased, Δ N slightly declined for bulk muscle tissue in both experiments; increased for AA in the low-fat, high-fiber diet (A); and remained the same or decreased for AA in the high-fat, low-fiber diet (B). The effects of dietary protein on Δ N and on TDF varied by AA but were consistent between variables.
CONCLUSIONS
Diets were less digestible and included more protein in Experiment A than in Experiment B. As a result, the mice in Experiment A probably oxidized more AA, resulting in greater Δ N values. However, the similar responses of Δ N and of TDF to diet variation suggest that if diet samples are available, Δ N accurately tracks trophic position. If diet samples are not available, the patterns presented here provide a basis to interpret Δ N values. The trophic-source offset of Pro-Lys did not vary across diets, and therefore may be more reliable for omnivores than other offsets (e.g., Glu-Phe).
Topics: Amino Acids; Animal Feed; Animals; Body Weight; Dietary Fats; Dietary Fiber; Dietary Proteins; Metabolism; Mice; Muscle, Skeletal; Nitrogen Isotopes; Oxidation-Reduction; Proteolysis
PubMed: 33634533
DOI: 10.1002/rcm.9073 -
Canadian Journal of Diabetes Apr 2013Evidence shows that the metabolism of protein is altered in type 2 diabetes mellitus and insulin resistance not only applies to glucose and lipid but protein metabolism... (Review)
Review
Evidence shows that the metabolism of protein is altered in type 2 diabetes mellitus and insulin resistance not only applies to glucose and lipid but protein metabolism as well. Population surveys report greater susceptibility to loss of lean tissue and muscle strength with aging in diabetes. Prevention of sarcopenia requires that protein receives more attention in dietary prescriptions. Protein intake of 1-1.2 g/kg of body weight (with weight at a body mass index of 25 kg/m(2))/day may be distributed equally among 3 meals a day, including breakfast, to optimize anabolism. Adopting a dietary pattern that provides a high plant-to-animal ratio and greater food volume favouring consumption of vegetables, legumes, fruits, complemented with fish, low fat dairy and meat (preferably cooked slowly in moisture), soy and nuts may assist with metabolic and weight control. Depending on the magnitude of energy restriction, usual protein intake should be maintained or increased, and the caloric deficit taken from fat and carbohydrate foods. Exercise before protein-rich meals improves skeletal muscle protein anabolism. Because high levels of amino acids lower glucose uptake in individuals without diabetes, the challenge remains to define the optimal protein intake and exercise regimen to protect from losses of muscle mass and strength while maintaining adequate glucose control in type 2 diabetes.
Topics: Adult; Age Factors; Diabetes Mellitus, Type 2; Diet; Dietary Proteins; Female; Humans; Insulin Resistance; Male; Middle Aged; Young Adult
PubMed: 24070802
DOI: 10.1016/j.jcjd.2013.01.007 -
Nutrition Reviews Mar 1982
Review
Topics: Adipose Tissue; Adult; Animals; Child; Dietary Proteins; Energy Metabolism; Female; Humans; Male; Nutritional Requirements; Obesity; Rats
PubMed: 7050777
DOI: 10.1111/j.1753-4887.1982.tb05276.x -
Nutrition Reviews Jan 1987
Review
Topics: Adolescent; Adult; Animals; Dietary Proteins; Humans; Nutritional Requirements; Pyridoxine
PubMed: 3547195
DOI: 10.1111/j.1753-4887.1987.tb06070.x -
Annual Review of Medicine 1990Dietary protein is normally assimilated in an efficient manner following the action of gastrointestinal proteases. A number of pathological conditions can alter this... (Review)
Review
Dietary protein is normally assimilated in an efficient manner following the action of gastrointestinal proteases. A number of pathological conditions can alter this process, with deleterious nutritional consequences.
Topics: Adult; Dietary Proteins; Digestion; Humans; Intestinal Absorption; Reference Values
PubMed: 2184718
DOI: 10.1146/annurev.me.41.020190.001025 -
The Journal of Nutrition Jul 2001This article examines the proposition that dietary protein in pre- and early postnatal life influences the development of adiposity in later life. In rodents, low... (Review)
Review
This article examines the proposition that dietary protein in pre- and early postnatal life influences the development of adiposity in later life. In rodents, low protein intake during gestation can result in low birth weight and subsequently leads to various metabolic disturbances in adulthood, such as high blood pressure, impaired glucose tolerance and insulin resistance. The few controlled studies conducted in animals suggest that high protein or energy intake during gestation leads to low birth weights. Observational studies in humans have been inconclusive in establishing a relationship between dietary protein intake in pregnancy and effects on birth weight and adiposity of the offspring later in life. There is only weak epidemiological evidence linking high protein intake during early childhood and the development of obesity. By contrast, studies in domestic animals have found that higher levels of protein intake are often associated with lower rates of fat accretion. Additional studies are proposed to explore claims linking protein nutrition in early life to the postnatal development of obesity and disease in humans.
Topics: Adipose Tissue; Aging; Animals; Birth Weight; Body Composition; Dietary Proteins; Female; Fetus; Growth; Humans; Infant; Infant Nutritional Physiological Phenomena; Infant, Newborn; Male; Nutritional Physiological Phenomena; Obesity; Pregnancy; Rodentia
PubMed: 11435530
DOI: 10.1093/jn/131.7.2062