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1.
Surg Obes Relat Dis ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38862297

RESUMO

BACKGROUND: The stage of life at the onset of obesity is an important factor in assessing inflammatory state and cardiometabolic risk. OBJECTIVES: This study aimed to evaluate the relationship between the obesity onset and the inflammatory profile in women with severe obesity. SETTING: Public hospital, Brazil. METHODS: Forty-eight women with severe obesity (20-59 yr old) were evaluated according to weight, height, neck circumference (NC), waist circumference (WC), and hip circumference, as well blood metabolic and inflammatory parameters. The participants were grouped according to obesity onset stage of life (early group: ≤19 yr; late group: >19 yr). RESULTS: The demographic means of the participants were: age of 39.7 years, weight of 122.7 kg and body mass index (BMI) of 48.4 kg/m2. The late group presented significantly higher values of leptin (lep)/adiponectin (adipo) ratio and homeostatic model assessment for insulin resistance (HOMA-IR) than the early group. The late group also had a lower adipo/lep ratio. Moreover, the late group showed correlations between the lep/adipo ratio and BMI (r = .460, P = .021), NC (r = .478, P = .016), and WC (r = .535, P = .006). Adipo was also correlated with NC (r = -.418, P = .038), WC (r = -.437, P = .029), and glycated hemoglobin (HbA1C) (r = -.485, P = .019). By contrast, in the early group, the lep/adipo ratio showed correlations with insulin (r = .647, P = .004) and HOMA-B (r = .564, P = .015). CONCLUSIONS: The inflammatory profile is correlated with anthropometric values in women with late-onset obesity. Inflammatory markers seemed to correlate with the glycemic profile in women with early-onset obesity. Furthermore, inflammation was higher in women with late-onset obesity compared to those with early-onset obesity.

2.
Environ Monit Assess ; 196(6): 583, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806740

RESUMO

Agriculture is an essential economic activity in Brazil. However, it is also the main source of water quality degradation. Monitoring catchments with agricultural land use is a way to generate information on a scale to identify causes and sources of water quality degradation. This work used monitoring data derived from hydrology and the quality of surface and underground water in an intensive agricultural catchment in the Atlantic Forest biome. The Fortaleza River catchment is located in the western part of Santa Catarina state in southern Brazil and has 62 km2 of drainage area. Hydrological and water quality monitoring was conducted for 7 years at two fluviometric stations, three lysimeters, one meteorological station, and one piezometer. Data on precipitation, temperature, water flow, surface runoff, drainage, and water quality were used. Statistical analyses were also developed. Precipitation between 2013 and 2019 presented a homogeneous distribution in monthly and annual data, with January and July the months with the highest and lowest values, respectively. Statistical difference in the average and Q95 flows was found in upstream and downstream fluviometric sections. In terms of quality, statistical differences were identified for ammonium, nitrate, and potassium concentrations, which had higher concentrations in lysimeter runoff, indicating direct influence of agricultural activity on water quality. Principal component analysis (PCA) indicated that (i) surface water presented a positive relationship in Component 1 for the magnesium-calcium, sulphate-chloride, and acetate-bromide groups and a negative relationship for phosphate-nitrate; (ii) in lysimeters, the positive relationship occurred for Component 2 for the phosphate-chloride and sulphate-nitrate groups and was negative for ammonium-lithium and calcium-potassium-magnesium; and (iii) in piezometer, positive relationships were found for chloride-sodium and phosphate-nitrite pairs, while negative relationships were found for calcium-magnesium.


Assuntos
Agricultura , Monitoramento Ambiental , Florestas , Poluentes Químicos da Água , Brasil , Monitoramento Ambiental/métodos , Animais , Poluentes Químicos da Água/análise , Suínos , Rios/química , Qualidade da Água , Nitratos/análise
3.
Nutrition ; 124: 112449, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696907

RESUMO

Chronic wounds are characterized by prolonged non-healing, significantly affecting patients' quality of life. Oral formulas may enhance the wound healing process and contribute to cost reduction in care. This review aimed to evaluate the effects of oral nutritional supplementation on chronic wound healing and provide insights into formula characteristics. A comprehensive search across Cinahl, Embase, PubMed, and Web of Science databases yielded nine studies from the past decade involving 741 patients ages 52 to 81.7 across various care settings: hospitals, long-term care facilities, and home care. Primary wound types included pressure injuries (58%), diabetic foot ulcers (40%), and venous ulcers (2%). The intervention duration ranged from 2 to 16 wk, with sample sizes varying from 24 to 270 patients. Notably, four studies reported a reduction in wound area and an increased healing rate with a hypercaloric, hyperproteic formula enriched with zinc and vitamins A, C, and E. However, two studies found no significant differences compared with control groups. Two other studies investigated a combination of arginine, glutamine, and ß-hydroxy-ß-methylbutyrate; however, they did not yield significant results, and one study favored a hyperproteic formula instead of a hyperproteic formula with arginine. This review provides evidence supporting the potential of oral nutritional supplementation to enhance the healing process of chronic wounds. Based on our findings, a desirable formula should be characterized by a high calorie and protein content and the inclusion of antioxidant micronutrients, including, but not limited to, vitamins A, E, C, and zinc.

4.
Eur J Case Rep Intern Med ; 10(12): 004119, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38077712

RESUMO

Drug-induced liver injury (DILI) is a liver condition caused by any drug or toxic substance. The spectrum of DILI manifestations can range from asymptomatic elevation of liver enzymes to acute liver failure. Antibiotics are one of the major causes of DILI. The authors report the case of a 37-year-old male with nausea, right hypochondrium pain and fever with history of bismuth subcitrate, metronidazole and tetracycline combination treatment in the previous five days. DILI was suspected and other aetiologies of acute hepatitis were excluded such as viral, autoimmune or even haemochromatosis and Wilson's disease. Liver biopsy was performed, being compatible with the diagnosis of DILI; DILI is a diagnosis of exclusion. Bismuth subcitrate, metronidazole and tetracycline combination treatment is a rare cause of DILI. LEARNING POINTS: Bismuth subcitrate, metronidazole and tetracycline in combination is a rare cause of drug-induced liver injury (DILI).DILI is an exclusion diagnosis.Liver biopsy has an important role in the diagnosis of DILI.

5.
Telemed Rep ; 4(1): 327-335, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37908625

RESUMO

Background: e-Health interventions can potentially improve health care. My Viva Plan® (MVP) is a web-based program that focuses on mindfulness, nutrition, and physical fitness. The aim of this study was to evaluate the effects of this platform on stress indicators and diet quality among first-year university students. Methods: Ninety-seven university students were enrolled in a randomized, controlled clinical trial. Participants were randomized into control (n = 49) and MVP (n = 48) groups. Perceived stress was measured using the self-report Stress Indicator Questionnaire. Diet quality was assessed by the nutrient-rich foods index, and body composition was assessed by a hand-to-foot, multifrequency, bioelectrical impedance analysis. Results: There were no differences in physical, sleep, behavioral, emotional, and personal habit indicators between groups. Diet quality and body composition were similar between groups, except among women in the MVP group with decreased body fat (-1.2 ± 2.6 kg, p < 0.05). Participant engagement was low: 50% of the MVP group did not access the platform. Conclusions: The MVP web-based intervention was not associated with improvements in stress indicators, diet quality, and body composition, likely due to the characteristics of our cohort of healthy young individuals. Future studies should focus on enhancing motivational approaches to explore the potential of e-health interventions that improve health behavior.Clinical Trial Registration number: NCT03579264A.

6.
Nutrients ; 15(14)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37513538

RESUMO

The ketogenic diet (KD) is, nowadays, considered an interesting nutritional approach for weight loss and improvement in insulin resistance. Nevertheless, most of the studies available in the literature do not allow a clear distinction between its effects on insulin sensitivity per se, and the effects of weight loss induced by KDs on insulin sensitivity. In this review, we discuss the scientific evidence on the direct and weight loss mediated effects of KDs on glycemic status in humans, describing the KD's biochemical background and the underlying mechanisms.


Assuntos
Dieta Cetogênica , Resistência à Insulina , Humanos , Redução de Peso
7.
Front Sports Act Living ; 5: 1192025, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37440875

RESUMO

Objective: The aim of this study was to assess the construct validity and reliability of the Portuguese Physical Literacy Assessment (PPLA) instruments (a questionnaire and a tool using teacher-reported data). We also investigated the conceptual and practical implications of reflective vs. formative measurement of Physical Literacy using the PPLA. Methods: Multiple Confirmatory Factor Analysis (CFA) and Confirmatory Composite Analysis (CCA) models were used complementarily to assess construct validity in a sample of 521 grade 10-12 Portuguese students from Lisbon, Portugal. Bifactor model-based indices (ω), Explained Common Variance (ECV), and Percentage of Uncontaminated Correlations (PUC) were used to assess score reliability and adequacy. Results: Using CFA, an asymmetrical bifactor model (S*1-1) provided the best fit to the data [Robust Comparative Fit Index = 97, Robust Root Mean Square Error Of Approximation = 0.05 (0.04-0.06), Standardized Root Mean Square Residual (SRMR) = 0.04], while CCA resulted in the best absolute fit for single first-order composite models (dG, dL, and SRMR below or borderline of their 95% critical value). Through a reflective paradigm, the total PL score should not be used in isolation (ECV = 0.49, ωH = 0.71, lower than recommended 0.80). Subscales for the Physical, Psychological, and Social domains attained acceptable reliability scores (ωs = 0.76, 0.82, 0.80, and 0.60). Conclusions: A general trait of PL accounts for considerable variance in all indicators. We advise calculation of a total summed PL score and domain scores, which should be interpreted conjointly in applied settings. Despite both paradigms being tenable, future research efforts should use a bifactor measurement model, which permits disentanglement of the variance attributed to the general PL trait and its domains. Overall, evidence supported the construct validity and reliability of the PPLA for its intended use as an integrated tool to measure PL as a multidimensional construct in 15- to 18-year-old Portuguese students in a physical education setting.

9.
Nutrients ; 15(7)2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37049529

RESUMO

This study aimed to investigate the effect of chemotherapy (CT) and its different types of regimens on the anthropometry and body composition of women with breast cancer. Three-hundred-and-four women with breast cancer were enrolled in this multicenter study. The participants were evaluated before the infusion of the first cycle of CT (pre-CT), and until two weeks after CT completion (post-CT), regarding body weight, body mass index (BMI); waist circumference (WC); waist-to-height ratio (WHtR); conicity index (C-index); fat mass index (FMI); and fat-free mass index (FFMI). CT regimens were classified as anthracycline-based (AC-doxorubicin or epirubicin); anthracyclines and taxane (ACT); cyclophosphamide, methotrexate, and 5-fluorouracil (CMF); or isolated taxanes (paclitaxel or docetaxel). Women significantly increased BMI and FMI post-CT (p < 0.001 and p = 0.007, respectively). The ACT regimen increased FMI (p < 0.001), while FFMI increased after AC (p = 0.007). It is concluded that the CT negatively impacted body composition and the type of regime had a strong influence. The ACT regimen promoted an increase in FMI compared to other regimens, and the AC increased FFMI. These findings reinforce the importance of nutritional monitoring of breast cancer patients throughout the entire CT treatment.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Brasil , Composição Corporal , Docetaxel/uso terapêutico , Ciclofosfamida/uso terapêutico , Fluoruracila/uso terapêutico , Índice de Massa Corporal , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
10.
Adv Nutr ; 14(4): 840-857, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37031749

RESUMO

The gut microbiome has a profound influence on host physiology, including energy metabolism, which is the process by which energy from nutrients is transformed into other forms of energy to be used by the body. However, mechanistic evidence for how the microbiome influences energy metabolism is derived from animal models. In this narrative review, we included human studies investigating the relationship between gut microbiome and energy metabolism -i.e., energy expenditure in humans and energy harvest by the gut microbiome. Studies have found no consistent gut microbiome patterns associated with energy metabolism, and most interventions were not effective in modulating the gut microbiome to influence energy metabolism. To date, cause-and-effect relationships and mechanistic evidence on the impact of the gut microbiome on energy expenditure have not been established in humans. Future longitudinal observational studies and randomized controlled trials utilizing robust methodologies and advanced statistical analysis are needed. Such knowledge would potentially inform the design of therapeutic avenues and specific dietary recommendations to improve energy metabolism through gut microbiome modulation.


Assuntos
Microbioma Gastrointestinal , Microbiota , Animais , Humanos , Microbioma Gastrointestinal/fisiologia , Dieta , Nutrientes , Metabolismo Energético/fisiologia
11.
Percept Mot Skills ; 130(3): 958-983, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36861939

RESUMO

We examined the construct validity and reliability of the previously developed Psychological and Social modules of the Portuguese Physical Literacy Assessment Questionnaire (PPLA-Q) using Mokken Scale Analysis in a sample of 508 Portuguese adolescents in public schools in Lisbon. We used a retest subsample (n = 73) to calculate the Intraclass Correlation Coefficient. Eight PPLA-Q scales can be interpreted as moderate-to-strong Mokken scales (H = .47-.66) with good total-score reliability (ρ = .83-.94), and moderate-to-excellent test-retest reliability (ICC95%CI = .51-.95); four scales had an interpretable invariant item ordering. All but the Physical Regulation scale functioned similarly across sex. Scale-scores correlated as expected, with low-to-moderate correlations across domains supporting convergent and discriminant validity. These results support the construct validity and reliability of the PPLA-Q to assess the psychological and social domains of physical literacy in Portuguese adolescents (15-18 years) enrolled in physical education.


Assuntos
Alfabetização , Instituições Acadêmicas , Humanos , Adolescente , Portugal , Reprodutibilidade dos Testes , Inquéritos e Questionários , Psicometria
12.
Clin Nutr ESPEN ; 53: 224-237, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36657917

RESUMO

BACKGROUND & AIMS: It is well known that dietary fiber positively impacts the microbiome and health as a whole. However, the health effects of ß-glucan, a dietary fiber extracted from oats, have been questioned when administered alone or incorporated into other foods. The purpose of this systematic review and meta-analysis was to evaluate the impact of oats or ß-glucan supplements on the lipid profile. METHODS: Randomized controlled trials with parallel-arm or crossover blinded interventions at least two weeks in duration, for hyperlipidemic or non-hyperlipidemic men and women ≥18 years of age were selected. Only single (participants blinded) or double-blinded studies that compared oat or isolated ß-glucan with a placebo/control group were considered for this review. The databases EMBASE, PubMed, Web of science and CINHAL were searched, from the earliest indexed year available online to the end of January 2022. Random-effects models were used to combine the estimated effects extracted from individual studies, and data were summarized as standardized mean difference (SMD) and 95% confidence interval (95%CI). RESULTS: A total of 811 articles were screened for eligibility, and relevant data were extracted from 28 studies, totaling 1494 subjects. Oat interventions TC (-0.61, 95%CI: -0.84;-0.39, p < 0.00001, and -0.70, 95%CI: -1.07;-0.34, p = 0.0002, respectively) and LDL (-0.51, 95%CI: -0.71;-0.31, p < 0.00001, and -0.38, 95%CI: -0.60;-0.15, p = 0.001, respectively). Moreover, isolated ß-glucan interventions from parallel-arm studies decreased TC (-0.73, 95%CI: -1.01;-0.45, p < 0.00001), LDL (-0.58, 95%CI: -0.85;-0.32, p < 0.0001) and triglycerides (-0.30, 95%CI: -0.49;-0.12, p = 0.001). HDL was not altered by either oat or isolated ß-glucan (p > 0.05). CONCLUSION: Overall, this review showed that both oat and isolated ß-glucan interventions improved lipid profiles. Furthermore, the ingestion of oats or isolated ß-glucan supplements are effective tools to combat dyslipidemia and should be considered in cardiovascular disease prevention.


Assuntos
beta-Glucanas , Masculino , Humanos , Feminino , beta-Glucanas/farmacologia , Avena , Ensaios Clínicos Controlados Aleatórios como Assunto , Triglicerídeos , Suplementos Nutricionais , Grão Comestível , Fibras na Dieta/farmacologia
13.
Nutr Rev ; 81(2): 153-167, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35950956

RESUMO

CONTEXT: Strenuous exercise may lead to negative acute physiological effects that can impair athletic performance. Some recent studies suggest that probiotic supplementation can curtail these effects by reducing the permeability of the intestinal barrier, yet results are inconsistent. OBJECTIVE: The aim of this systematic review is to assess the effects of probiotic supplementation on athletic performance. DATA SOURCES: The PubMed/MEDLINE, Cochrane, and Scopus databases were searched for articles that assessed the effects of probiotic supplementation on athletic performance. DATA EXTRACTION THIS SYSTEMATIC REVIEW IS REPORTED ACCORDING TO: PRISMA guidelines. Risk of bias was assessed through the Cochrane RoB 2.0 tool. Seventeen randomized clinical trials assessing athletic performance as the primary outcome were included. In total, 496 individuals (73% male) comprising athletes, recreationally trained individuals, and untrained healthy individuals aged 18 to 40 years were investigated. DATA ANALYSIS: Three studies showed an increase or an attenuation of aerobic performance (decline in time to exhaustion on the treadmill) after supplementation with probiotics, while 3 found an increase in strength. However, most studies (n = 11) showed no effect of probiotic consumption on aerobic performance (n = 9) or muscular strength (n = 2). The most frequently used strain was Lactobacillus acidophilus, used in 2 studies that observed positive results on performance. Studies that used Lactobacillus plantarum TK10 and Lactobacillus plantarum PS128 also demonstrated positive effects on aerobic performance and strength, but they had high risk of bias, which implies low confidence about the actual effect of treatment. CONCLUSION: There is not enough evidence to support the hypothesis that probiotics can improve performance in resistance and aerobic exercises. Further well-controlled studies are warranted.


Assuntos
Desempenho Atlético , Probióticos , Humanos , Masculino , Feminino , Probióticos/uso terapêutico , Exercício Físico , Desempenho Atlético/fisiologia , Atletas , Força Muscular
14.
Foods ; 12(23)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38231704

RESUMO

Health-promoting compounds in wine and wine-related products are important due to their potential benefits to human health. Through an extensive literature review, this study explores the presence of these compounds in wine and wine-related products, examining their relationship with terroir and their impact on the aromatic and flavor properties that are perceived orally: sunlight exposure, rainfall patterns, and soil composition impact grapevines' synthesis and accumulation of health-promoting compounds. Enzymes, pH, and the oral microbiome are crucial in sensory evaluation and perception of health promotion. Moreover, their analysis of health-promoting compounds in wine and wine-related products relies on considerations such as the specific target compound, selectivity, sensitivity, and the complexity of the matrix.

15.
J Clin Med ; 11(19)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36233551

RESUMO

Background: The dosage and safety of nutritional supplements for patients with venous ulcers are still not well established. Aim: To evaluate the effects of a high calorie, high protein, arginine-, zinc-, and vitamins A, C, and E-enriched nutritional supplement on the biochemical profile, dietary intake, anthropometry, muscle strength, and characteristics of lesions of patients with venous ulcers. Methods: A controlled before−after clinical trial with a four-week follow-up involved 27 patients with venous ulcers under outpatient treatment in Brazil. It was administered in two to three doses per day (200 mL each) of a high-calorie and high-protein supplement enriched with arginine, zinc, and vitamins A, C, and E. Patients were assessed for anthropometric parameters, dietary intake, biochemical tests, and healing conditions according to the Pressure Ulcer Scale for Healing (PUSH). Results: It was observed that an increase in energy and protein supply led to an adequate intake of immunonutrients (zinc and vitamins A, C, and E), increased body weight, increased body mass index, and stronger handgrip strength. The injury area and the score on the PUSH notably decreased after the intervention (p < 0.001). Conclusions: The administered supplement, at the tested dosage, improved the nutritional status and characteristics of lesions in patients with venous ulcers.

16.
Cell Host Microbe ; 30(6): 764-785, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35679823

RESUMO

Given the worldwide epidemic of diet-related chronic diseases, evidence-based dietary recommendations are fundamentally important for health promotion. Despite the importance of the human gut microbiota for the physiological effects of diet and chronic disease etiology, national dietary guidelines around the world are just beginning to capitalize on scientific breakthroughs in the microbiome field. In this review, we discuss contemporary nutritional recommendations from a microbiome science perspective, focusing on mechanistic evidence that established host-microbe interactions as mediators of the physiological effects of diet. We apply this knowledge to inform discussions of nutrition controversies, advance innovative dietary strategies, and propose an experimental framework that integrates the microbiome into nutrition research. The congruence of key paradigms in the nutrition and microbiome disciplines validates current recommendations in dietary guidelines, and the systematic incorporation of microbiome science into nutrition research has the potential to further improve and innovate healthy eating.


Assuntos
Microbioma Gastrointestinal , Dieta , Dieta Saudável , Microbioma Gastrointestinal/fisiologia , Humanos , Estado Nutricional
17.
Clin Nutr ; 41(6): 1328-1334, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35576845

RESUMO

BACKGROUND & AIMS: Muscle quality index (MQI) is used to measure the quality of the muscles. It is defined as the ratio of muscle strength per unit of muscle mass, but since this might vary by rage and ethnicity, we aimed to develop sex, and population-specific normative data and cutoff values for MQI (extremally low and low) using the arm or appendicular skeletal muscle mass (ASM) obtained from a population-representative sample. METHODS: This cross-sectional analysis included data from 4849 volunteers (aged 20-59 years) from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. Measures of handgrip strength (HGS) were performed using a hand dynamometer. ASM was assessed by dual-energy X-ray absorptiometry (DXA). Arm ASM mass was used to calculate MQIArm [dominant HGS/dominant arm ASM (kg/kg)]; ASM was used to calculate MQIApp [dominant HGS/ASM (kg/kg)]; and the sum of the non-dominant hand and dominant hand were used to calculate MQItotal [HGS sum/ASM (kg/kg)]. Cutoff values were derived from a young reference subgroup (n = 1625 aged, 20-39 years), with low and extremely low MQI defined as 1 and 2 sex-specific standard deviations below the mean, respectively. RESULTS: MQIArm, MQIApp, and MQITotal differed by sex and population studied. Overall, using the proposed cutoffs, men showed lower values of MQIArm than women, and higher MQIApp, and MQITotal values. Compared to non-Hispanic Whites, non-Hispanic Asians had higher values of MQI while non-Hispanic Black people had lower values. CONCLUSION: MQIs cutoffs were established for both sexes and different populations studied. MQIArm, MQIApp, and MQITotal values were lower after the fifth-decade in men, but not in women.


Assuntos
Força da Mão , Sarcopenia , Absorciometria de Fóton , Estudos Transversais , Feminino , Força da Mão/fisiologia , Humanos , Masculino , Força Muscular , Músculo Esquelético/fisiologia , Inquéritos Nutricionais , Sarcopenia/diagnóstico
18.
Adv Nutr ; 13(5): 1866-1881, 2022 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-35580578

RESUMO

To identify how variables such as exercise condition, supplementation strategy, participant characteristics and demographics, and practices that control oral microbiota diversity could modify the effect of inorganic nitrate ingestion (as nitrate salt supplements, beetroot juice, and nitrate-rich vegetables) on exercise performance, we conducted a systematic review with meta-analysis. Studies were identified in PubMed, Embase, and Cochrane databases. Eligibility criteria included randomized controlled trials assessing the effect of inorganic nitrate on exercise performance in healthy adults. To assess the variation in effect size, we used meta-regression models for continuous variables and subgroup analysis for categorical variables. A total of 123 studies were included in this meta-analysis, comprising 1705 participants. Nitrate was effective for improving exercise performance (standardized mean difference [SMD]: 0.101; 95% CI: 0.051, 0.151, P <0.001, I2 = 0%), although nitrate salts supplementation was not as effective (P = 0.629) as ingestion via beetroot juice (P <0.001) or a high-nitrate diet (P = 0.005). Practices that control oral microbiota diversity influenced the nitrate effect, with practices harmful to oral bacteria decreasing the ergogenic effect of nitrate. The ingestion of nitrate was most effective for exercise lasting between 2 and 10 min (P <0.001). An inverse dose-response relation between the fraction of inspired oxygen and the effect size (coefficient: -0.045, 95% CI: -0.085, -0.005, P = 0.028) suggests that nitrate was more effective in increasingly hypoxic conditions. There was a dose-response relation for acute administration (P = 0.049). The most effective acute dose was between 5 and 14.9 mmol provided ≥150 min prior to exercise (P <0.001). An inverse dose-response for protocols ≥2 d was observed (P = 0.025), with the optimal dose between 5 and 9.9 mmol·d-1 (P <0.001). Nitrate, via beetroot juice or a high-nitrate diet, improved exercise performance, in particular, in sessions lasting between 2 and 10 min. Ingestion of 5-14.9 mmol⋅d-1 taken ≥150 min prior to exercise appears optimal for performance gains and athletes should be aware that practices controlling oral microbiota diversity may decrease the effect of nitrate.


Assuntos
Beta vulgaris , Substâncias para Melhoria do Desempenho , Adulto , Suplementos Nutricionais , Ingestão de Alimentos , Humanos , Nitratos/farmacologia , Oxigênio , Sais
19.
Am J Clin Nutr ; 115(4): 991-1004, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34978321

RESUMO

Chronobiology plays a crucial role in modulating many physiologic systems in which there is nutritional synergism with meal timing. Given that intermittent fasting (IF) has grown as a flexible dietary method consisting of delayed or early eating windows, this scoping review addresses the effects of IF protocols on metabolism as they relate to clinical nutrition and the circadian system. Although nocturnal habits are associated with circadian misalignments and impaired cardiometabolic profile-and nutritional physiology is better orchestrated during the day-most findings are based on animal experiments or human studies with observational designs or acute meal tests. Well-controlled randomized clinical trials employing IF protocols of delayed or early eating windows have sometimes demonstrated clinical benefits, such as improved glycemic and lipid profiles, as well as weight loss. However, IF does not appear to be more effective than traditional diets at the group level, and its effects largely depend on energy restriction. Thus, efforts must be made to identify patient biological rhythms, preferences, routines, and medical conditions before individual dietary prescription in clinical practice.


Assuntos
Jejum , Redução de Peso , Animais , Glicemia , Ritmo Circadiano , Dieta , Humanos , Refeições/fisiologia , Redução de Peso/fisiologia
20.
Eur J Clin Nutr ; 76(2): 212-219, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33986493

RESUMO

BACKGROUND: Bioelectrical impedance analysis (BIA) is a widely used method for estimating body composition. Avoiding foods/beverages containing caffeine is a frequently enforced pre-test protocol to ensure reliability of BIA measurements. However, few studies have evaluated whether this is necessary, with conflicting results. We aimed to determine whether the coffee consumption differing in caffeine content influences BIA parameters in healthy adults. METHODS: Twenty-five healthy adults were enrolled in a randomized, double-blind cross-over trial. Three amounts of caffeine were given with 200 mL of coffee: 0 mg (11 g of decaffeinated), 200 mg (5.5 g of caffeinated plus 5.5 g of decaffeinated), and 400 mg of caffeine (11 g of caffeinated). BIA measurements were conducted at 6 different times, and coefficient variations (CV) explored. RESULTS: No differences were observed for group × time interaction on impedance, resistance, or reactance (p > 0.05). Values of BIA parameters increased after 30-min of coffee consumption, independently of the caffeine dosage (all p < 0.001). Body fat percentage followed the same pattern and increased after 45-min (p < 0.05). Median CV for consecutive impedance, resistance, and reactance measurements were >95%CI of expected device measurement error over 70-min, without difference between groups. Urine output volume was not different between groups (decaffeinated: 440.45 ± 197.57 mL; 200 mg: 471.80 ± 171.88 mL; 400 mg: 489.30 ± 204.10 mL, p > 0.05). CONCLUSION: Coffee consumption influenced BIA-derived results after 70-min but was not related to caffeine content, likely due to water intake.


Assuntos
Cafeína , Café , Adulto , Estudos Cross-Over , Método Duplo-Cego , Impedância Elétrica , Humanos , Reprodutibilidade dos Testes
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