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1.
Nutrients ; 16(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38999799

RESUMO

The aim of this study was to evaluate the potential interplay between a carbohydrate diet and inflammation in atherosclerotic cardiovascular disease (ASCVD) development. ATTICA is a prospective observational study of 3042 adults free of cardiovascular disease (CVD) who were recruited in 2002 and followed for 20 years. Baseline data on carbohydrate intake and inflammatory biomarker levels were collected. Participants were stratified by carbohydrate intake (low vs. high: 190 g/day) and carbohydrate quality. At the 20-year follow-up in 2022, 1988 participants had complete data for CVD assessment. The overall quantity and quality of carbohydrate intake did not show a significant association with CVD incidence; inflammatory markers were positively correlated with an increased risk of CVD (p-values < 0.05). Chronic systemic inflammation seems to affect the CVD risk of participants who had a higher carbohydrate intake more substantially, as compared to those with low intake. Additionally, individuals with higher high carbohydrate/low fiber intake experienced a higher risk of inflammation-related CVD, compared to those with high carbohydrate/high fiber intake. The presented findings revealed that the effect of inflammation markers on the CVD risk is influenced both by the amount and quality of carbohydrate intake, irrespective of overall dietary habits and clinical and lifestyle characteristics.


Assuntos
Biomarcadores , Doenças Cardiovasculares , Carboidratos da Dieta , Inflamação , Humanos , Masculino , Feminino , Inflamação/sangue , Pessoa de Meia-Idade , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/epidemiologia , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/efeitos adversos , Estudos Prospectivos , Adulto , Biomarcadores/sangue , Fatores de Risco de Doenças Cardíacas , Fatores de Risco , Idoso , Comportamento Alimentar , Incidência , Dieta/efeitos adversos
2.
Nutrients ; 16(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38999832

RESUMO

BACKGROUND: The differential effects of pecans versus other popular snack foods on appetite and blood markers of metabolism and satiety have not been well studied. This study investigated the effects of a single mid-morning snack of pecans or tortilla chips on subjective appetite, food intake, blood measures of hormones and metabolites, and resting energy expenditure. METHODS: Twenty participants with overweight and obesity were enrolled in a within-participants, randomized crossover trial. Participants had indwelling catheters placed for blood sampling and were fed a standardized breakfast, followed two hours later by a 250 kcal snack of either pecans or tortilla chips, and then by a self-selected lunch. Visual analog scale (VAS) appetite measures, blood markers, and energy expenditure were taken at intervals after food consumption. RESULTS: VAS ratings, energy, food intake and macronutrient composition did not differ between treatment conditions, but glucose and insulin were significantly more elevated after tortilla chips. Free fatty acids (FFA), triglycerides (TG), peptide YY (PYY), and glucagon-like peptide-1 (GLP-1) were higher after consuming pecans compared to tortilla chips. CONCLUSIONS: Pecan consumption improves postprandial glucose and insulin profiles which would be beneficial to individuals at risk of developing type 2 diabetes. Further studies are needed to investigate whether increased relative secretion of PYY and GLP-1 after eating pecans versus tortilla chips may affect subjective appetite and energy intake if consumed chronically.


Assuntos
Apetite , Biomarcadores , Estudos Cross-Over , Metabolismo Energético , Insulina , Obesidade , Sobrepeso , Lanches , Humanos , Masculino , Feminino , Adulto , Obesidade/sangue , Biomarcadores/sangue , Sobrepeso/sangue , Insulina/sangue , Glicemia/metabolismo , Peptídeo 1 Semelhante ao Glucagon/sangue , Pessoa de Meia-Idade , Voluntários Saudáveis , Ingestão de Alimentos/fisiologia , Ingestão de Energia , Carboidratos da Dieta/administração & dosagem , Peptídeo YY/sangue , Período Pós-Prandial , Adulto Jovem
3.
Nutrients ; 16(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38999863

RESUMO

The emptying rate of specific nutrients in enteral formulas is poorly understood, despite the importance of controlling the emptying rate in tube-fed patients. Because of their viscosity, thickened formulas are widely used to avoid gastric reflux and reduce the burden on caregivers. This study examined how thickeners in enteral formulas affected the gastric emptying rates of proteins and carbohydrates. A semi-dynamic gastric model was used to prepare and digest test enteral formulas that contained either no thickeners or agar (0.2%). The amounts of protein and carbohydrates in each emptied aliquot were determined, and the emptying rate was calculated. We found that agar accelerated protein emptying, and an exploratory experiment with agar (0.5%) suggested the possibility of concentration dependence. Additionally, experiments using gellan gum (0.08%), guar gum (0.2%), or carrageenan (0.08%, 0.2%) suggested that protein emptying could vary depending on the thickener type and that carrageenan might slow it. These results could help with the appropriate selection of thickeners added to liquid foods based on the patient's metabolic profile to manage nutrition, not only for tube-fed patients but also for those with oropharyngeal dysphagia or diabetes.


Assuntos
Proteínas Alimentares , Nutrição Enteral , Alimentos Formulados , Galactanos , Esvaziamento Gástrico , Mananas , Gomas Vegetais , Esvaziamento Gástrico/efeitos dos fármacos , Nutrição Enteral/métodos , Humanos , Mananas/farmacologia , Mananas/administração & dosagem , Viscosidade , Galactanos/farmacologia , Proteínas Alimentares/administração & dosagem , Carboidratos da Dieta/administração & dosagem , Carragenina , Ágar , Polissacarídeos Bacterianos/farmacologia , Modelos Biológicos
4.
Nutrients ; 16(13)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38999884

RESUMO

BACKGROUND: The sleep-low method has been proposed as a way to sleep in a low-glycogen state, increase the duration of low glycogen availability and sleep and temporarily restrict carbohydrates to improve exercise performance. However, long-term dietary restriction may induce mental stress in athletes. Therefore, if it can be shown that the effects of the sleep-low method can be achieved by restricting the carbohydrate intake at night (the nighttime carbohydrate restriction method), innovative methods could be developed to reduce weight in individuals with obesity and enhance athletes' performance with reduced stress and in a shorter duration when compared with those of previous studies. With this background, we conducted a study with the purpose of examining the intervention effects of a short-term intensive nighttime carbohydrate restriction method. METHODS: A total of 22 participants were recruited among university students participating in sports club activities. The participants were assigned at random to groups, including a nighttime carbohydrate restriction group of 11 participants (6 males, 5 females; age 22.3 ± 1.23) who started a carbohydrate-restricted diet and a group of 11 participants (5 males, 6 females; age 21.9 ± 7.9) who continued with their usual diet. The present study had a two-group parallel design. In the first week, no dietary restrictions were imposed on either group, and the participants consumed their own habitual diets. In the second week, the total amount of calories and carbohydrate intake measured in the first week were divided by seven days, and the average values were calculated. These were used as the daily calorie and carbohydrate intakes in the second week. Only the nighttime carbohydrate restriction group was prohibited from consuming carbohydrates after 4:00 p.m. During the two-week study period, all participants ran for one hour each day before breakfast at a heart rate of 65% of their maximum heart rate. RESULTS: The results obtained from young adults participating in sports showed significant differences in peak oxygen consumption (V·O2peak), work rate max, respiratory quotient (RQ), body weight and lean body mass after the intervention when compared with before the intervention in the nighttime carbohydrate restriction group (p < 0.05). CONCLUSIONS: Our findings suggest that the nighttime carbohydrate restriction method markedly improves fat metabolism even when performed for a short period. This method can be used to reduce body weight in individuals with obesity and enhance athletes' performance. However, it is important to consider the intake of nutrition other than carbohydrates.


Assuntos
Dieta com Restrição de Carboidratos , Exercício Físico , Humanos , Masculino , Feminino , Adulto Jovem , Dieta com Restrição de Carboidratos/métodos , Adulto , Exercício Físico/fisiologia , Carboidratos da Dieta/administração & dosagem , Metabolismo dos Lipídeos/fisiologia , Sono/fisiologia , Desempenho Atlético/fisiologia , Adolescente , Ingestão de Energia , Fatores de Tempo
5.
J Int Soc Sports Nutr ; 21(1): 2377178, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39007897

RESUMO

BACKGROUND: Physique athletes are subjectively judged on their on-stage esthetic per their competition division criteria. To succeed, competitors look to acutely enhance their appearance by manipulating nutritional variables in the days leading up to competition, commonly referred to as peak week (PW). Despite their documented wide adoption, PW strategies lack experimental evidence. Further, the relationship between the specific strategies and the characteristics of the competitors who implement them are unknown. The aim of this research was to examine the effect of competitor characteristics on the specific nutritional peaking strategies implemented, the length of these strategies, and the range of daily carbohydrate (CHO) intakes during these strategies. METHODS: A 58-item survey was developed to gather information on peak week nutrition and training practices of physique athletes. A total of 160 respondents above the age of 18 who had competed in the last 5 years completed the nutrition section. The topics analyzed for this paper included competitor demographics, peaking strategies utilized, and PW CHO intakes. Competitor demographics are presented with the use of descriptive statistics. Associations between competitor demographics and peaking strategies implemented, peaking strategy length, and daily CHO intake ranges were assessed using multiple logistic regression, multiple ordinal logistic regression, and linear mixed models, respectively. RESULTS: From the sampled population, ages 24-39 years (71.2%), male (68.8%), natural (65%), and amateur (90%) were the most common characteristics from their respective categories, while mean competition preparation length was 20.35 ± 8.03 weeks (Males: 19.77 ± 7.56 weeks, Females: 21.62 ± 8.93 weeks), competition preparation body mass loss was 11.5 ± 5.56 kg (M: 12.7 ± 5.76 kg, F: 7.16 ± 3.99 kg), and competition body mass was 72.09 ± 15.74 kg (M: 80.15 ± 11.33 kg, F: 54.34 ± 7.16 kg). For males, the highest and lowest daily CHO intake during PW were 489.63 ± 224.03 g (6.22 ± 2.93 g/kg body mass) and 148.64 ± 152.01 g (1.94 ± 2.17 g/kg), respectively, while for females these values were 266.73 ± 131.23 g (5.06 ± 2.67 g/kg) and 94.42 ± 80.72 g (1.81 ± 1.57 g/kg), respectively. CHO back loading (45%) and water loading (40.6%) were the most popular peaking strategies, while the most prevalent peaking strategy length was 7 days (27.2%). None of the competitor characteristics predicted the use of CHO-based peaking strategies nor peaking strategy length. For non-CHO-based strategies, drug-enhanced competitors were more likely to restrict water than non-drug enhanced, while males and professional competitors had greater odds of loading sodium than females and amateurs, respectively. Finally, when comparing the disparity in highest and lowest CHO intakes during peak week, sex was the only significant factor. CONCLUSIONS: The results of this survey provide further information on the nutritional peaking strategies implemented by competitors. Certain characteristics were identified as predictors of sodium loading and water restriction, and the range of daily PW CHO intake. Contrastingly, no associations were found for CHO-based peaking strategies or peaking strategy length. While our analyses may be underpowered, and thus results should be interpreted with caution, it appears the nutritional peaking strategies implemented by physique competitors are seemingly complex and highly individual.


Assuntos
Carboidratos da Dieta , Fenômenos Fisiológicos da Nutrição Esportiva , Humanos , Feminino , Masculino , Adulto , Adulto Jovem , Carboidratos da Dieta/administração & dosagem , Atletas , Comportamento Competitivo/fisiologia , Inquéritos e Questionários , Desempenho Atlético/fisiologia
7.
Nutrients ; 16(11)2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38892551

RESUMO

The care needs of children and adolescents with type 1 diabetes and their families are frequently approached as if they were identical to those of adults, overlooking the distinct challenges young people may face. It has been stated that children and adolescents often find conventional conversations with diabetes specialists tiresome and unpleasant. The present study focuses on familial experiences of an advanced carbohydrate counting program tailored to children and adolescents. The data encompass semi-structured interviews with families who participated in a group-based child-centered advanced carbohydrate counting program. The analysis revealed five themes: (1) peer-to-peer interaction is an essential determinant of sharing and learning; (2) illness perception significantly influences dietary intake; (3) normalization of diabetes in everyday life eases the disease burden; (4) repetition of dietary knowledge is important for retention; and (5) creating a safe and playful learning environment is crucial to engaging children and adolescents in their own treatment. The present findings suggest that it would be beneficial to explore and consider alternative teaching approaches that are adapted to a more interactive and engaging learning environment that is specifically tailored to children and adolescents. This entails moving away from traditional individual approaches.


Assuntos
Diabetes Mellitus Tipo 1 , Educação de Pacientes como Assunto , Pesquisa Qualitativa , Humanos , Diabetes Mellitus Tipo 1/psicologia , Adolescente , Criança , Feminino , Masculino , Educação de Pacientes como Assunto/métodos , Carboidratos da Dieta/administração & dosagem , Conhecimentos, Atitudes e Prática em Saúde , Família/psicologia , Adulto
8.
Nutrients ; 16(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38892591

RESUMO

The nutrient intake of persons with diabetes placed on a low-carbohydrate diet remains unclear. This study aimed to assess nutrient intake in persons with type 2 diabetes mellitus treated with a low-carbohydrate diet. The brief-type self-administered diet history questionnaire was used to collect the dietary information of 335 outpatients at Kitasato Institute Hospital, while their clinical characteristics were collected from their electronic medical records. The median age, HbA1c level, and body mass index of the participants were 68 (60-74) years, 49 (45-55) mmol/mol [6.7 (6.3-7.2)%], and 24.0 (21.8-26.7) kg/m2, respectively; median energy intake was 1457 (1153-1786) kcal/day; and protein-energy, fat-energy, and available carbohydrate-energy ratios were 18.6 (15.7-21.4)%E, 36.8 (31.6-43.2)%E, and 34.6 (26.0-42.4)%E, respectively. As the available carbohydrate-energy ratio decreased, the fat-energy ratio increased significantly. The total dietary fibre and salt intake were 7.1 (5.6-8.4) g/1000 kcal and 6.5 (5.6-7.5) g/1000 kcal, respectively. Japanese individuals with type 2 diabetes mellitus placed on a low-carbohydrate diet had a fat-to-energy ratio exceeding 30%, while the fat-energy ratio increased as the carbohydrate-energy ratio decreased.


Assuntos
Diabetes Mellitus Tipo 2 , Dieta com Restrição de Carboidratos , Ingestão de Energia , Humanos , Diabetes Mellitus Tipo 2/dietoterapia , Dieta com Restrição de Carboidratos/métodos , Masculino , Pessoa de Meia-Idade , Feminino , Idoso , Japão , Inquéritos sobre Dietas , Fibras na Dieta/administração & dosagem , Carboidratos da Dieta/administração & dosagem , Hemoglobinas Glicadas/metabolismo , Hemoglobinas Glicadas/análise , Índice de Massa Corporal , População do Leste Asiático
9.
Nutrients ; 16(11)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38892623

RESUMO

INTRODUCTION: Type 1 Diabetes (T1D) presents self-management challenges, requiring an additional 180 daily decisions to regulate blood glucose (BG) levels. Despite the potential, T1D-focused applications have a 43% attrition rate. This work delves into the willingness of people living with T1D (PwT1D) to use technology. METHOD: An online questionnaire investigated the current practices for carbohydrate estimation, nutritional tracking, and attitudes towards technology engagement, along with hypothetical scenarios and preferences regarding technology use. RESULTS: Thirty-nine responses were collected from PwT1D (n = 33) and caregivers (n = 6). Nutrition reporting preferences varied, with 50% favoring 'type and scroll' while 30% preferred meal photographing. Concerning the timing of reporting, 33% reported before meals, 55% after, and 12% at a later time. Improved Time in Range (TIR) was a strong motivator for app use, with 78% expressing readiness to adjust insulin doses based on app suggestions for optimizing TIR. Meal descriptions varied; a single word was used in 42% of cases, 23% used a simple description (i.e., "Sunday dinner"), 30% included portion sizes, and 8% provided full recipes. CONCLUSION: PwT1D shows interest in using technology to reduce the diabetes burden when it leads to an improved TIR. For such technology to be ecologically valid, it needs to strike a balance between requiring minimal user input and providing significant data, such as meal tags, to ensure accurate blood glucose management without overwhelming users with reporting tasks.


Assuntos
Diabetes Mellitus Tipo 1 , Humanos , Diabetes Mellitus Tipo 1/sangue , Feminino , Masculino , Adulto , Inquéritos e Questionários , Pessoa de Meia-Idade , Refeições , Aplicativos Móveis , Glicemia/metabolismo , Adulto Jovem , Estado Nutricional , Automonitorização da Glicemia , Insulina , Carboidratos da Dieta/administração & dosagem
10.
Bull Exp Biol Med ; 176(6): 722-726, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38888650

RESUMO

We studied the effect of separate and combined influence of chronic forced physical activity reduction and high-fat and high-carbohydrate diet containing cholesterol on some indicators of carbohydrate, lipid, and cholesterol metabolism in growing male Wistar rats. Used combination of factors simulating a sedentary lifestyle and unhealthy diet did not have a synergistic effect on the selected biomarkers. On the contrary, the effect was antagonistic: body weight and appetite decreased and insulin resistance increased. The obtained results indicate certain prospects of hypercholesterolemia model using in preclinical studies of specialized food products to optimize the diet of individuals with disorders of carbohydrate and lipid metabolism.


Assuntos
Colesterol , Dieta Hiperlipídica , Metabolismo dos Lipídeos , Ratos Wistar , Animais , Masculino , Ratos , Dieta Hiperlipídica/efeitos adversos , Metabolismo dos Lipídeos/efeitos dos fármacos , Colesterol/metabolismo , Colesterol/sangue , Resistência à Insulina , Peso Corporal/efeitos dos fármacos , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/farmacologia , Hipercolesterolemia/metabolismo , Hipercolesterolemia/dietoterapia , Imobilização , Colesterol na Dieta/administração & dosagem , Apetite/efeitos dos fármacos , Apetite/fisiologia , Condicionamento Físico Animal/fisiologia
11.
Nutrients ; 16(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38931241

RESUMO

It is a common belief amongst strength and power athletes that nutritional supplementation strategies aid recovery by shifting the anabolic/catabolic profile toward anabolism. Factors such as nutrient quantity, nutrient quality, and nutrient timing significantly impact upon the effectiveness of nutritional strategies in optimizing the acute responses to resistance exercise and the adaptive response to resistance training (i.e., muscle growth and strength expression). Specifically, the aim of this review is to address carbohydrates (CHOs), protein (PRO), and/or amino acids (AAs) supplementation strategies, as there is growing evidence suggesting a link between nutrient signaling and the initiation of protein synthesis, muscle glycogen resynthesis, and the attenuation of myofibrillar protein degradation following resistance exercise. Collectively, the current scientific literature indicates that nutritional supplementation strategies utilizing CHO, PRO, and/or AA represents an important approach aimed at enhancing muscular responses for strength and power athletes, primarily increased muscular hypertrophy and enhanced strength expression. There appears to be a critical interaction between resistance exercise and nutrient-cell signaling associated with the principle of nutrient timing (i.e., pre-exercise, during, and post-exercise). Recommendations for nutritional supplementation strategies to promote muscular responses for strength and athletes are provided.


Assuntos
Aminoácidos , Atletas , Carboidratos da Dieta , Proteínas Alimentares , Suplementos Nutricionais , Força Muscular , Músculo Esquelético , Treinamento Resistido , Fenômenos Fisiológicos da Nutrição Esportiva , Humanos , Proteínas Alimentares/administração & dosagem , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/metabolismo , Aminoácidos/metabolismo , Aminoácidos/administração & dosagem , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Força Muscular/efeitos dos fármacos
12.
Nutrients ; 16(12)2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38931251

RESUMO

BACKGROUND: Testing and evaluating athletes is necessary and should include performance, body composition, and nutrition. The purpose of this study was to report assessments of dietary intake, V˙O2max, and body composition in D1 collegiate athletes and examine relationships between these assessments. METHODS: Dietary intake was assessed with 3-day recalls and compared to recommendations, and body composition was assessed via bioelectrical impedance analysis (BIA) (n = 48). V˙O2max was evaluated using a graded exercise test (GXT) with a verification bout (n = 35). Reliability between "true" V˙O2max and verification was determined. Correlations and regressions were performed. RESULTS: Energy, carbohydrate, and micronutrient intake was lower than recommendations. Mean V˙O2max was 47.3 and 47.4 mL·kg-1·min-1 for GXT and verification, respectively. While correlations were apparent among dietary intake, V˙O2max, and body composition, percent fat-free mass (%FFM) predicted 36% of V˙O2max. CONCLUSIONS: Collegiate athletes are not meeting energy and carbohydrate recommendations and exceed fat recommendations. Vitamin D and magnesium were low in all sports, and iron and calcium were low in females. V˙O2max ranged from 35.6 to 63.0 mL·kg-1·min-1, with females below average and males meeting typical values for their designated sport. Assessing D1 athletes can provide guidance for sports dietitians, coaches, and strength and conditioning specialists to track and monitor nutrition in athletes.


Assuntos
Atletas , Composição Corporal , Estado Nutricional , Humanos , Feminino , Masculino , Adulto Jovem , Desempenho Atlético/fisiologia , Ingestão de Energia , Consumo de Oxigênio/fisiologia , Universidades , Adolescente , Impedância Elétrica , Carboidratos da Dieta/administração & dosagem , Avaliação Nutricional , Teste de Esforço/métodos , Dieta , Fenômenos Fisiológicos da Nutrição Esportiva
13.
Nutrients ; 16(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38931324

RESUMO

Global increases in metabolic disorders such as type 2 diabetes (T2D), especially within Asian populations, highlight the need for novel approaches to dietary intervention. The Tu Ora study previously evaluated the effects on metabolic health of including a nut product into the diet of a New Zealand cohort of Chinese participants with overweight and normoglycaemia or prediabetes through a 12-week randomised, parallel-group clinical trial. In this current study, we compared the impact of this higher-protein nut bar (HP-NB) versus a higher-carbohydrate cereal bar (HC-CB) on the faecal microbiome by employing both 16S rRNA gene amplicon and shotgun metagenomic sequencing of pre- and post-intervention pairs from 84 participants. Despite the higher fibre, protein, and unsaturated fat content of nuts, there was little difference between dietary groups in gut microbiome composition or functional potential, with the bacterial phylum Firmicutes dominating irrespective of diet. The lack of observed change suggests the dietary impact of the bars may have been insufficient to affect the gut microbiome. Manipulating the interplay between the diet, microbiome, and metabolic health may require a more substantial and/or prolonged dietary perturbation to generate an impactful modification of the gut ecosystem and its functional potential to aid in T2D risk reduction.


Assuntos
Carboidratos da Dieta , Grão Comestível , Microbioma Gastrointestinal , Nozes , Sobrepeso , Estado Pré-Diabético , Humanos , Estado Pré-Diabético/dietoterapia , Estado Pré-Diabético/microbiologia , Masculino , Sobrepeso/microbiologia , Feminino , Carboidratos da Dieta/administração & dosagem , Pessoa de Meia-Idade , Nova Zelândia , Adulto , Fezes/microbiologia , Povo Asiático , China , RNA Ribossômico 16S/genética , Diabetes Mellitus Tipo 2/microbiologia , Dieta Rica em Proteínas , Proteínas Alimentares/administração & dosagem , População do Leste Asiático
14.
J Int Soc Sports Nutr ; 21(1): 2368167, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38934469

RESUMO

POSITION STATEMENT: The International Society of Sports Nutrition (ISSN) provides an objective and critical review of the use of a ketogenic diet in healthy exercising adults, with a focus on exercise performance and body composition. However, this review does not address the use of exogenous ketone supplements. The following points summarize the position of the ISSN.1. A ketogenic diet induces a state of nutritional ketosis, which is generally defined as serum ketone levels above 0.5 mM. While many factors can impact what amount of daily carbohydrate intake will result in these levels, a broad guideline is a daily dietary carbohydrate intake of less than 50 grams per day.2. Nutritional ketosis achieved through carbohydrate restriction and a high dietary fat intake is not intrinsically harmful and should not be confused with ketoacidosis, a life-threatening condition most commonly seen in clinical populations and metabolic dysregulation.3. A ketogenic diet has largely neutral or detrimental effects on athletic performance compared to a diet higher in carbohydrates and lower in fat, despite achieving significantly elevated levels of fat oxidation during exercise (~1.5 g/min).4. The endurance effects of a ketogenic diet may be influenced by both training status and duration of the dietary intervention, but further research is necessary to elucidate these possibilities. All studies involving elite athletes showed a performance decrement from a ketogenic diet, all lasting six weeks or less. Of the two studies lasting more than six weeks, only one reported a statistically significant benefit of a ketogenic diet.5. A ketogenic diet tends to have similar effects on maximal strength or strength gains from a resistance training program compared to a diet higher in carbohydrates. However, a minority of studies show superior effects of non-ketogenic comparators.6. When compared to a diet higher in carbohydrates and lower in fat, a ketogenic diet may cause greater losses in body weight, fat mass, and fat-free mass, but may also heighten losses of lean tissue. However, this is likely due to differences in calorie and protein intake, as well as shifts in fluid balance.7. There is insufficient evidence to determine if a ketogenic diet affects males and females differently. However, there is a strong mechanistic basis for sex differences to exist in response to a ketogenic diet.


Assuntos
Desempenho Atlético , Dieta Cetogênica , Fenômenos Fisiológicos da Nutrição Esportiva , Humanos , Desempenho Atlético/fisiologia , Composição Corporal , Cetose , Ciências da Nutrição e do Esporte , Carboidratos da Dieta/administração & dosagem , Exercício Físico/fisiologia , Resistência Física/fisiologia
15.
Nutr Diabetes ; 14(1): 47, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937460

RESUMO

BACKGROUND: Clinical guidelines recommend basic carbohydrate counting (BCC), or similar methods to improve carbohydrate estimation skills and to strive for higher consistency in carbohydrate intake potentially improving glycaemic control. However, evidence for this approach in type 2 diabetes (T2D) is limited. OBJECTIVE: To examine the efficacy of a structured education program in BCC as add-on to standard dietary care on glycaemic control in individuals with T2D. METHODS: The BCC Study was a randomized, controlled, open-label, parallel-group trial. Individuals with T2D aged 18-75 years with glycated haemoglobin A1c (HbA1c) 53-97 mmol/mol (7.0-11.0%) were randomly assigned (1:1) to BCC or standard dietary care. The primary outcomes were differences in changes in HbA1c or glycaemic variability (calculated as mean amplitude of glycaemic excursions [MAGE]) between groups after six months of intervention. RESULTS: Between September 2018 and July 2021, 48 participants were randomly assigned, 23 to BCC and 25 to standard dietary care. Seven participants did not receive the allocated intervention. From a baseline-adjusted mean of 65 mmol/mol (95% CI 62-68 [8.1%, 7.8-8.4]), HbA1c changed by -5 mmol/mol (-8 to -1 [-0.5%, -0.7 to -0.1]) in BCC and -3 mmol/mol (-7 to 1 [-0.3%, -0.6 to 0.1]) in standard care with an estimated treatment effect of -2 mmol/mol (-7 to 4 [-0.2%, -0.6 to 0.4]); p = 0.554. From a baseline-adjusted mean of 4.2 mmol/l (3.7 to 4.8), MAGE changed by -16% (-33 to 5) in BCC and by -3% (-21 to 20) in standard care with an estimated treatment effect of -14% (-36 to 16); p = 0.319. Only median carbohydrate estimation error in favour of BCC (estimated treatment difference -55% (-70 to -32); p < 0.001) remained significant after multiple testing adjustment. CONCLUSIONS: No glycaemic effects were found but incorporating BCC as a supplementary component to standard dietary care led to improved skills in estimating carbohydrate intake among individuals with T2D.


Assuntos
Glicemia , Diabetes Mellitus Tipo 2 , Hemoglobinas Glicadas , Controle Glicêmico , Humanos , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/terapia , Pessoa de Meia-Idade , Masculino , Feminino , Controle Glicêmico/métodos , Hemoglobinas Glicadas/análise , Idoso , Glicemia/análise , Glicemia/metabolismo , Adulto , Carboidratos da Dieta/administração & dosagem , Educação de Pacientes como Assunto/métodos , Adolescente , Adulto Jovem , Dieta com Restrição de Carboidratos/métodos , Resultado do Tratamento
16.
Lancet Digit Health ; 6(7): e489-e499, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38906614

RESUMO

BACKGROUND: In type 1 diabetes, carbohydrate counting is the standard of care to determine prandial insulin needs, but it can negatively affect quality of life. We developed a novel insulin-and-pramlintide closed-loop system that replaces carbohydrate counting with simple meal announcements. METHODS: We performed a randomised crossover trial assessing 14 days of (1) insulin-and-pramlintide closed-loop system with simple meal announcements, (2) insulin-and-placebo closed-loop system with carbohydrate counting, and (3) insulin-and-placebo closed-loop system with simple meal announcements. Participants were recruited at McGill University Health Centre (Montreal, QC, Canada). Eligible participants were adults (aged ≥18 years) and adolescents (aged 12-17 years) with type 1 diabetes for at least 1 year. Participants were randomly assigned in a 1:1:1:1:1:1 ratio to a sequence of the three interventions, with faster insulin aspart used in all interventions. Each intervention was separated by a 14-45-day wash-out period, during which participants reverted to their usual insulin. During simple meal announcement interventions, participants triggered a prandial bolus at mealtimes based on a programmed fixed meal size, whereas during carbohydrate counting interventions, participants manually entered the carbohydrate content of the meal and an algorithm calculated the prandial bolus based on insulin-to-carbohydrate ratio. Two primary comparisons were predefined: the percentage of time in range (glucose 3·9-10·0 mmol/L) with a non-inferiority margin of 6·25% (non-inferiority comparison); and the mean Emotional Burden subscale score of the Diabetes Distress Scale (superiority comparison), comparing the insulin-and-placebo system with carbohydrate counting minus the insulin-and-pramlintide system with simple meal announcements. Analyses were performed on a modified intention-to-treat basis, excluding participants who did not complete all interventions. Serious adverse events were assessed in all participants. This trial is registered on ClinicalTrials.gov, NCT04163874. FINDINGS: 32 participants were enrolled between Feb 14, 2020, and Oct 5, 2021; two participants withdrew before study completion. 30 participants were analysed, including 15 adults (nine female, mean age 39·4 years [SD 13·8]) and 15 adolescents (eight female, mean age 15·7 years [1·3]). Non-inferiority of the insulin-and-pramlintide system with simple meal announcements relative to the insulin-and-placebo system with carbohydrate counting was reached (difference -5% [95% CI -9·0 to -0·7], non-inferiority p<0·0001). No statistically significant difference was found in the mean Emotional Burden score between the insulin-and-pramlintide system with simple meal announcements and the insulin-and-placebo system with carbohydrate counting (difference 0·01 [SD 0·82], p=0·93). With the insulin-and-pramlintide system with simple meal announcements, 14 (47%) participants reported mild gastrointestinal symptoms and two (7%) reported moderate symptoms, compared with two (7%) participants reporting mild gastrointestinal symptoms on the insulin-and-placebo system with carbohydrate counting. No serious adverse events occurred. INTERPRETATION: The insulin-and-pramlintide system with simple meal announcements alleviated carbohydrate counting without degrading glucose control, although quality of life as measured by the Emotional Burden score was not improved. Longer and larger studies with this novel approach are warranted. FUNDING: Juvenile Diabetes Research Foundation.


Assuntos
Estudos Cross-Over , Diabetes Mellitus Tipo 1 , Hipoglicemiantes , Insulina Aspart , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Refeições , Humanos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Feminino , Masculino , Adolescente , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/administração & dosagem , Polipeptídeo Amiloide das Ilhotas Pancreáticas/administração & dosagem , Polipeptídeo Amiloide das Ilhotas Pancreáticas/uso terapêutico , Criança , Adulto , Insulina Aspart/uso terapêutico , Insulina Aspart/administração & dosagem , Glicemia/análise , Sistemas de Infusão de Insulina , Canadá , Adulto Jovem , Insulina/análogos & derivados , Insulina/uso terapêutico , Insulina/administração & dosagem , Carboidratos da Dieta/administração & dosagem , Quebeque , Pessoa de Meia-Idade
17.
J Neuroinflammation ; 21(1): 151, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840215

RESUMO

BACKGROUND: Mounting evidence links glucose intolerance and diabetes as aspects of metabolic dysregulation that are associated with an increased risk of developing dementia. Inflammation and inflammasome activation have emerged as a potential link between these disparate pathologies. As diet is a key factor in both the development of metabolic disorders and inflammation, we hypothesize that long term changes in dietary factors can influence nervous system function by regulating inflammasome activity and that this phenotype would be sex-dependent, as sex hormones are known to regulate metabolism and immune processes. METHODS: 5-week-old male and female transgenic mice expressing a caspase-1 bioluminescent reporter underwent cranial window surgeries and were fed control (65% complex carbohydrates, 15% fat), high glycemic index (65% carbohydrates from sucrose, 15% fat), or ketogenic (1% complex carbohydrates, 79% fat) diet from 6 to 26 weeks of age. Glucose regulation was assessed with a glucose tolerance test following a 4-h morning fast. Bioluminescence in the brain was quantified using IVIS in vivo imaging. Blood cytokine levels were measured using cytokine bead array. 16S ribosomal RNA gene amplicon sequencing of mouse feces was performed to assess alterations in the gut microbiome. Behavior associated with these dietary changes was also evaluated. RESULTS: The ketogenic diet caused weight gain and glucose intolerance in both male and female mice. In male mice, the high glycemic diet led to increased caspase-1 biosensor activation over the course of the study, while in females the ketogenic diet drove an increase in biosensor activation compared to their respective controls. These changes correlated with an increase in inflammatory cytokines present in the serum of test mice and the emergence of anxiety-like behavior. The microbiome composition differed significantly between diets; however no significant link between diet, glucose tolerance, or caspase-1 signal was established. CONCLUSIONS: Our findings suggest that diet composition, specifically the source and quantity of carbohydrates, has sex-specific effects on inflammasome activation in the central nervous system and behavior. This phenotype manifested as increased anxiety in male mice, and future studies are needed to determine if this phenotype is linked to alterations in microbiome composition.


Assuntos
Caspase 1 , Dieta Cetogênica , Camundongos Transgênicos , Caracteres Sexuais , Animais , Feminino , Masculino , Camundongos , Caspase 1/metabolismo , Dieta Cetogênica/efeitos adversos , Carboidratos da Dieta/efeitos adversos , Carboidratos da Dieta/farmacologia , Sistema Nervoso Central/metabolismo , Microbioma Gastrointestinal/fisiologia , Camundongos Endogâmicos C57BL
18.
J Int Soc Sports Nutr ; 21(1): 2365307, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38860870

RESUMO

BACKGROUND: Sports nutrition is an impactful component to sports performance. The purpose of the current study was to investigate the sports nutrition knowledge of National Collegiate Athletic Association collegiate athletes and assess self-reported perceived requirements for energy and macronutrient intake. A secondary aim was to evaluate the awareness of physical and emotional perceptions associated with mindful eating. METHODS: Participants included NCAA Division I (DI, n = 45), II (DII, n = 31), and III (DIII, n = 47) athletes. Athletes completed a validated questionnaire designed to assess sports nutrition knowledge and were asked questions about their perceived dietary energy and macronutrient requirements. Daily energy intake values were calculated using a recommended relative energy intake value of 40, 50, and 60 kcal/kg/day for low, moderate, and high activity levels, respectively. Carbohydrate recommendations were calculated using 4, 6, and 8 g/kg/day, protein recommendations were calculated using relative intakes of 1.4, 1.6, and 1.8 g/kg/day, and fat recommendations were calculated from a relative percentage of total predicted daily energy requirements, equating to 15, 25, and 30% of daily energy. Additionally, athletes completed a questionnaire to assess mindfulness regarding eating habits. RESULTS: Overall, athletes answered 45.5 ± 13.5% of questions correctly on the nutrition questionnaire with significant differences observed between male (48.6 ± 13.6%) and female athletes (43.6 ± 13.2%; p = 0.044), as well as significant differences observed between DI athlete scores (38.8 ± 14.1%) and DII athletes (47.7 ± 11.4%; p = 0.002), and DI athletes and DIII athletes (51.71 ± 11.83%; p = <0.001). All athletes significantly (p < 0.001) underestimated daily energy intake requirements (female, 2,112 ± 575 kcal/day; male, 3,283 ± 538 kcal/day). The mindfulness eating habits total score was significantly higher in male athletes (65.1 ± 6.5) compared to female athletes (60.9 ± 9.5; p = 0.009). CONCLUSIONS: Division I, II, and III collegiate athletes have poor sports nutrition knowledge, with Division I athletes having exhibited lower scores compared to Division II and III athletes on the sports nutrition knowledge questionnaire. Athletes from all levels of collegiate sports underestimated their energy and macronutrient requirements. Differences in mindful eating habits among female and male athletes were also evident.


Assuntos
Atletas , Ingestão de Energia , Comportamento Alimentar , Conhecimentos, Atitudes e Prática em Saúde , Necessidades Nutricionais , Fenômenos Fisiológicos da Nutrição Esportiva , Humanos , Feminino , Masculino , Adulto Jovem , Atletas/psicologia , Inquéritos e Questionários , Nutrientes/administração & dosagem , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Adolescente , Gorduras na Dieta/administração & dosagem , Atenção Plena , Autorrelato
19.
An Pediatr (Engl Ed) ; 101(1): 36-45, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38906802

RESUMO

In this article we present a protocol for the use of the low-FODMAP diet in paediatric patients and review of the current evidence on its efficacy. These short-chain carbohydrates, which can be fermented by the intestinal microbiota, are found in a wide variety of foods, mainly of plant origin. The low-FODMAP diet is a therapeutic tool used for the management of gastrointestinal disorders such as irritable bowel syndrome. The sources we used were PubMed, Web of Science, Google Scholar and institutional websites. Following consumption of FODMAP-rich foods, a series of end products are generated that are not absorbed, giving rise to symptoms. Before starting a low-FODMAP diet, it is important to carry out a diagnostic evaluation including any applicable tests. Treatment is structured in 3 phases: elimination, reintroduction and personalization phase. In the first phase, FODMAP-rich foods are eliminated for 2-3 weeks. In the second phase, lasting 8 weeks, FODMAP-rich foods are gradually reintroduced. The last phase consists in customizing the diet according to individual tolerance. This article details which foods contain FODMAPs and possible substitutes. In addition, specific food diary/intake tracking and educational materials are provided in a series of appendices to facilitate adherence to the diet. Although most studies have been conducted in adults, there is also some evidence on the beneficial effects in the paediatric age group, with a reduction of symptoms, especially in patients with functional gastrointestinal disorders. Nevertheless, more research is required on the subject.


Assuntos
Gastroenteropatias , Humanos , Criança , Gastroenteropatias/dietoterapia , Gastroenteropatias/diagnóstico , Gastroenteropatias/terapia , Dieta com Restrição de Carboidratos/métodos , Síndrome do Intestino Irritável/dietoterapia , Síndrome do Intestino Irritável/diagnóstico , Carboidratos da Dieta/administração & dosagem , Dieta FODMAP
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