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BACKGROUND: Time restricted feeding (TRF) involves deliberately restricting the times during which energy is ingested. Preliminary findings suggest that 8-10-h TRF improves sleep. However, the effects of shorter TRF windows (4-6 h) on sleep, remain unknown. AIMS: This study compared the effects of 4-h versus 6-h TRF on sleep quality, duration, insomnia severity and the risk of obstructive sleep apnea. METHODS: Adults with obesity (n = 49) were randomized into one of three groups: 4-h TRF (eating only between 3 and 7 p.m.), 6-h TRF (eating only between 1 and 7 p.m.), or a control group (no meal timing restrictions) for 8 weeks. RESULTS: After 8 weeks, body weight decreased (p < 0.001) similarly by 4-h TRF (-3.9 ± 0.4 kg) and 6-h TRF (-3.4 ± 0.4 kg), versus controls. Sleep quality, measured by the Pittsburgh Sleep Quality Index (PSQI), did not change by 4-h TRF (baseline: 5.9 ± 0.7; week 8: 4.8 ± 0.6) or 6-h TRF (baseline: 6.4 ± 0.8; week 8: 5.3 ± 0.9), versus controls. Wake time, bedtime, sleep duration and sleep onset latency also remained unchanged. Insomnia severity did not change by 4-h TRF (baseline: 4.4 ± 1.0; week 8: 4.7 ± 0.9) or 6-h TRF (baseline: 8.3 ± 1.2; week 8: 5.5 ± 1.1), versus controls. Percent of participants reporting obstructive sleep apnea symptoms did not change by 4-h TRF (baseline: 44%; week 8: 25%) or 6-h TRF (baseline: 47%; week 8: 20%), versus controls. CONCLUSION: These findings suggest that 4- and 6-h TRF have no effect on sleep quality, duration, insomnia severity, or the risk of obstructive sleep apnea.
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Apneia Obstrutiva do Sono , Distúrbios do Início e da Manutenção do Sono , Adulto , Jejum , Humanos , Obesidade/complicações , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/etiologia , Qualidade do SonoRESUMO
PURPOSE OF REVIEW: Time-restricted eating (TRE) is a form of intermittent fasting that involves confining the eating window to 4-10 h and fasting for the remaining hours of the day. The purpose of this review is to summarize the current literature pertaining to the effects of TRE on body weight and cardiovascular disease risk factors. RECENT FINDINGS: Human trial findings show that TRE reduces body weight by 1-4% after 1-16 weeks in individuals with obesity, relative to controls with no meal timing restrictions. This weight loss results from unintentional reductions in energy intake (~350-500 kcal/day) that occurs when participants confine their eating windows to 4-10 h/day. TRE is also effective in lowering fat mass, blood pressure, triglyceride levels, and markers of oxidative stress, versus controls. This fasting regimen is safe and produces few adverse events. These findings suggest that TRE is a safe diet therapy that produces mild reductions in body weight and also lowers several key indicators of cardiovascular disease in participants with obesity.
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Ingestão de Energia , Jejum , Peso Corporal , Humanos , Obesidade , Redução de PesoRESUMO
BACKGROUND AND AIMS: This study examined if the weight loss and metabolic benefits of alternate day fasting (ADF) varies according to sex and menopausal status in adults with obesity. METHODS AND RESULTS: This secondary analysis pooled the data of men and women (n = 75) who participated in three 12-week ADF studies (500 kcal fast day; alternated with an ad libitum intake feast day). Body weight decreased in premenopausal women (-4.6 ± 3.2%), postmenopausal women (-6.5 ± 3.2%) and men (-6.2 ± 4.4%) (main effect of time, P < 0.001), with no difference between groups (no group × time interaction). Energy intake on fast days was higher than prescribed in all groups (â¼400-500 excess kcal consumed), with no differences between groups. Fat mass, lean mass, fasting insulin, and insulin resistance, and blood pressure decreased similarly in all groups (main effect of time, P < 0.05 for all comparisons). LDL cholesterol decreased more in postmenopausal versus premenopausal women (group × time interaction, P = 0.01). Fasting glucose, HDL cholesterol, and triglycerides remained unchanged in all groups. CONCLUSION: These findings suggest that the weight loss and metabolic benefits of ADF do not generally vary according to sex or menopausal status in adults with obesity. TRIAL REGISTRATION: Clinicaltrials.gov, NCT00960505; NCT03528317.
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Restrição Calórica , Jejum , Menopausa , Obesidade/dietoterapia , Redução de Peso , Adulto , Ensaios Clínicos como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/diagnóstico , Obesidade/fisiopatologia , Pós-Menopausa , Pré-Menopausa , Fatores Sexuais , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Time restricted feeding is a form of intermittent fasting where participants shorten the daily window in which they eat. AIM: This is the first study to examine the effects of intermittent fasting on changes in the gut microbiome. METHODS: Adults with obesity (n = 14) participated in a daily 8-hour time restricted feeding intervention (8-hour feeding window/16-hour fasting window) for 12 weeks. Fecal microbiota were determined by 16 S rRNA (ribosomal ribonucleic acid) gene sequencing of stool samples. RESULTS: Body weight decreased (P < 0.05) by -2 ± 1 kg. Gut microbiota phylogenetic diversity remained unchanged. The two most common phyla were Firmicutes and Bacteroidetes accounting for 61.2% and 26.9% of total abundance at baseline. No significant alterations in the abundance of Firmicutes, Bacteroidetes, or any other phyla were detected after 12 weeks of time restricted feeding. CONCLUSIONS: Time restricted feeding did not significantly alter the diversity or overall composition of the gut microbiome.
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Jejum , Microbioma Gastrointestinal , Obesidade/microbiologia , Adulto , Idoso , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Peso Corporal , Fezes/microbiologia , Comportamento Alimentar , Firmicutes/genética , Firmicutes/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Filogenia , Projetos Piloto , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Fatores de Tempo , Redução de PesoRESUMO
BACKGROUND: Alternate-day fasting (ADF) involves a 'famine day' (25% energy intake) and a 'feast day' (ad libitum intake). This secondary analysis examined changes in beverage intake in relation to energy intake and body weight during 12 months of ADF versus daily calorie restriction (CR). METHODS: Obese subjects (n = 100 enrolled, n = 69 completers) were randomized to one of three groups for 12 months: (a) ADF; (b) CR; or (c) control. RESULTS: At baseline, intakes of diet soda, caffeinated beverages, sugar-sweetened soda, alcohol, juice, and milk were similar between groups. There were no statistically significant changes in the intake of these beverages by month 6 or 12 between ADF (feast or famine day), CR, or control groups. Beverage intake was not related to energy intake or body weight at month 6 or 12 in any group. CONCLUSION: These pilot findings suggest that intermittent fasting does not impact beverage intake in a way that affects energy intake or body weight.
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Bebidas/estatística & dados numéricos , Peso Corporal/fisiologia , Ingestão de Energia/fisiologia , Jejum/fisiologia , Obesidade/dietoterapia , Adolescente , Adulto , Idoso , Bebidas Alcoólicas/estatística & dados numéricos , Animais , Restrição Calórica/métodos , Bebidas Gaseificadas/estatística & dados numéricos , Feminino , Seguimentos , Sucos de Frutas e Vegetais/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Leite/estatística & dados numéricos , Projetos Piloto , Bebidas Adoçadas com Açúcar/estatística & dados numéricos , Adulto JovemRESUMO
BACKGROUND: Preliminary evidence suggests that meal timing is associated with higher quality diets. Less is known about whether types of food consumed during specific eating episodes (i.e., day-level eating patterns) predict diet quality. OBJECTIVES: We investigated the association between day-level eating patterns and diet quality. METHODS: Decision tree models were built using 24-h dietary recall data from the National Health and Nutrition Examination Survey 2015 and 2017 cycles in a cross-sectional study. Sixteen food groups and 12 eating episodes (e.g., breakfast, lunch) were included as input parameters. Diet quality was scored using the Healthy Eating Index-2020 and categorized as higher or lower quality diets based on the median score. Mean decrease in impurity (MDI) ± standard deviation determined the relative contribution that day-level eating patterns had on diet quality; higher values represented greater contributions. RESULTS: We analyzed 12,597 dietary recalls from 9347 United States adults who were aged 18 y and older with ≥1 complete recall. Meals (breakfast, lunch, dinner) and respective snacking episodes had the greatest variety of dietary groups that contributed to the Healthy Eating Index-2020 score. Any whole-grain intake at breakfast predicted a higher quality diet (MDI = 0.08 ± 0.00), followed by lower solid fat intake (<8.94 g; MDI = 0.07 ± 0.00) and any plant protein intake at dinner (MDI = 0.05 ± 0.00). CONCLUSIONS: Day-level eating patterns were associated with diet quality, emphasizing the relevance of both food type and timing in relation to a high-quality diet. Future interventions should investigate the potential impact of targeting food type and timing to improve diet quality.
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The objectives were to discover the prevalence of disordered eating attitudes (EAs) among adolescent males and females, and the association of obesity with EA in seven Arab countries. A multistage stratified sampling technique was used to select secondary students aged 15-18 years from cities in Algeria, Jordan, Kuwait, Libya, Palestine, Syria and Sharijah Emirate (United Arab Emirates). The total sample was 4698 (2240 males and 2458 females). The Eating Attitudes Test (EAT-26) was used to measure those at risk of disordered EA. Obesity was calculated according to the International Obesity Taskforce criteria. Participants were grouped into two categories, non-obese and obese (overweight and obese). The risk of disordered EA was twice as high among females as in males in Jordan, Libya, Palestine and Syria. Kuwaiti adolescents (males and females) showed higher prevalence of disordered EA than their counterparts in other countries. The risk of disordered EA among obese adolescents was two to three times higher than that of non-obese adolescents, in both genders. Excepting Kuwaiti females and Palestinian males. The association of obesity with disordered EA was statistically significant. This study highlighted the magnitude of the risk of disordered eating attitudes among both male and female adolescents in Arab countries and identified the need for programmes to prevent and control these disorders in the Arab region.
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Comparação Transcultural , Comportamento Alimentar , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Obesidade/epidemiologia , Adolescente , Antropometria , Índice de Massa Corporal , Estudos Transversais , Transtornos da Alimentação e da Ingestão de Alimentos/complicações , Transtornos da Alimentação e da Ingestão de Alimentos/prevenção & controle , Feminino , Humanos , Masculino , Oriente Médio , Obesidade/complicações , Prevalência , Fatores Sexuais , Estudantes , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: To highlight the perceived personal, social, and environmental barriers to healthy eating and physical activity among Arab adolescents. METHOD: A multistage stratified sampling method was used to select 4698 students aged 15-18 years (2240 males and 2458 females) from public schools. Seven Arab counties were included in the study, namely, Algeria, Jordan, Kuwait, Libya, Palestine, Syria, and the United Arab Emirates. Self-reported questionnaire was used to list the barriers to healthy eating and physical activity facing these adolescents. RESULTS: It was found that lack of information on healthy eating, lack of motivation to eat a healthy diet, and not having time to prepare or eat healthy food were the main barriers to healthy eating among both genders. For physical activity, the main barriers selected were lack of motivation to do physical activity, less support from teachers, and lack of time to do physical activity. In general, females faced more barriers to physical activity than males in all countries included. There were significant differences between males and females within each country and among countries for most barriers. CONCLUSION: Intervention programmes to combat obesity and other chronic noncommunicable diseases in the Arab world should include solutions to overcome the barriers to weight maintenance, particularly the sociocultural barriers to practising physical activity.
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Exercício Físico , Comportamento Alimentar , Adolescente , Comparação Transcultural , Feminino , Humanos , Masculino , Oriente Médio , Inquéritos e QuestionáriosRESUMO
Objective: This study investigated how alternate-day fasting (ADF) combined with aerobic exercise impacts body weight and sleep in adults with non-alcoholic fatty liver disease (NAFLD). Methods: Adults with obesity and NAFLD (n = 80) were randomized into one of four groups for 3 months: combination of ADF (600 kcal "fast day," alternated with an ad libitum intake "feast day") and moderate-intensity aerobic exercise (five sessions per week, 60 min/session); ADF alone; exercise alone; or a no-intervention control group. Results: By month 3, body weight and intrahepatic triglyceride content decreased (p < 0.001, group × time interaction) in the combination group versus the exercise group and control group, but not versus the ADF group. Sleep quality, measured by the Pittsburgh Sleep Quality Inventory (PSQI), did not change in the combination group (baseline: 6.0 ± 0.7; month 3: 5.6 ± 0.7), ADF group (baseline: 8.9 ± 1.0; month 3: 7.5 ± 0.8), or exercise group (baseline: 6.4 ± 0.6; month 3: 6.7 ± 0.6), versus controls (baseline: 5.5 ± 0.7; month 3: 4.6 ± 0.5). Wake time, bedtime, sleep duration, and insomnia severity did not change (no group x time interaction) over the course of the study in any group. Risk for obstructive sleep apnea was present in 30% of combination subjects, 75% of ADF subjects, 40% of exercise subjects, and 75% of controls, and did not change in the intervention groups, versus controls, by month 3. No associations were observed between changes in body weight, intrahepatic triglyceride content, and any sleep outcome. Conclusions: The weight loss induced by ADF combined with exercise does not improve sleep quality, duration, insomnia severity, or risk of obstructive sleep apnea in individuals with NAFLD.
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Hepatopatia Gordurosa não Alcoólica , Apneia Obstrutiva do Sono , Distúrbios do Início e da Manutenção do Sono , Humanos , Adulto , Jejum , Obesidade/complicações , Obesidade/terapia , Peso Corporal , Exercício Físico , Triglicerídeos , SonoRESUMO
Innovative non-pharmacological lifestyle strategies to treat non-alcoholic fatty liver disease (NAFLD) are critically needed. This study compared the effects of alternate day fasting (ADF) combined with exercise to fasting alone, or exercise alone, on intrahepatic triglyceride (IHTG) content. Adults with obesity and NAFLD (n = 80, 81% female, age: 23-65 years) were randomized to 1 of 4 groups for 3 months: combination of ADF (600 kcal/2,500 kJ "fast day" alternated with an ad libitum intake "feast day") and moderate-intensity aerobic exercise (5 session per week, 60 min/session); ADF alone; exercise alone; or a no-intervention control group. By month 3, IHTG content was significantly reduced in the combination group (-5.48%; 95% CI, -7.77% to -3.18%), compared with the exercise group (-1.30%; 95% CI, -3.80% to 1.20%; p = 0.02) and the control group (-0.17%; 95% CI, -2.17% to 1.83%; p < 0.01) but was not significantly different versus the ADF group (-2.25%; 95% CI, -4.46% to -0.04%; p = 0.05). Body weight, fat mass, waist circumference, and alanine transaminase (ALT) levels significantly decreased, while insulin sensitivity significantly increased in the combination group compared with the control group. Lean mass, aspartate transaminase (AST), HbA1c, blood pressure, plasma lipids, liver fibrosis score, and hepatokines (fetuin-A, FGF-21, and selenoprotein P) did not differ between groups. Combining intermittent fasting with exercise is effective for reducing hepatic steatosis in patients with NAFLD but may offer no additional benefit versus fasting alone.
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Hepatopatia Gordurosa não Alcoólica , Adulto , Humanos , Feminino , Adulto Jovem , Pessoa de Meia-Idade , Idoso , Masculino , Hepatopatia Gordurosa não Alcoólica/terapia , Fígado , Exercício Físico , Peso Corporal , Triglicerídeos , JejumRESUMO
OBJECTIVE: Concerns have been raised regarding the impact of time-restricted eating (TRE) on sex hormones in females. This study examined how TRE affects sex steroids in premenopausal and postmenopausal females. METHODS: This is a secondary analysis of an 8-week TRE study (4- to 6-hour eating window) conducted in adults with obesity. Men and perimenopausal females were excluded. Females were classified into two groups based on menstrual status: premenopausal (n = 12) or postmenopausal (n = 11). RESULTS: After 8 weeks, body weight decreased in premenopausal females (-3% ± 2%) and postmenopausal females (-4% ± 2%) (main effect of time, p < 0.001), with no difference between groups (no group × time interaction). Circulating levels of testosterone, androstenedione, and sex hormone binding globulin (SHBG) did not change in either group (no group × time interaction). Dehydroepiandrosterone (DHEA) concentrations decreased (p < 0.05) in premenopausal (-14% ± 32%) and postmenopausal females (-13% ± 34%; main effect of time, p = 0.03), with no difference between groups. Estradiol, estrone, and progesterone were measured only in postmenopausal females, and they remained unchanged. CONCLUSIONS: In premenopausal females, androgens and SHBG remained unchanged during TRE, whereas DHEA decreased. In postmenopausal females, estrogens, progesterone, androgens, and SHBG did not change, but DHEA was reduced.
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Jejum Intermitente , Pós-Menopausa , Progesterona , Adulto , Feminino , Humanos , Androgênios , Desidroepiandrosterona , Estradiol , Hormônios Esteroides Gonadais , Globulina de Ligação a Hormônio Sexual/metabolismo , TestosteronaRESUMO
Intermittent fasting entails restricting food intake during specific times of day, days of the week, religious practice, or surrounding clinically important events. Herein, the metabolic and circadian rhythm mechanisms underlying the proposed benefits of intermittent fasting for the cancer population are described. We summarize epidemiological, preclinical, and clinical studies in cancer published between January 2020 and August 2022 and propose avenues for future research. An outstanding concern regarding the use of intermittent fasting among cancer patients is that fasting often results in caloric restriction, which can put patients already prone to malnutrition, cachexia, or sarcopenia at risk. Although clinical trials do not yet provide sufficient data to support the general use of intermittent fasting in clinical practice, this summary may be useful for patients, caregivers, and clinicians who are exploring intermittent fasting as part of their cancer journey for clinical outcomes and symptom management.
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Neoplasias , Obesidade , Humanos , Jejum Intermitente , Restrição Calórica/efeitos adversos , Dieta Redutora/efeitos adversos , Dieta Redutora/métodos , Ritmo Circadiano , Neoplasias/diagnóstico , Neoplasias/epidemiologia , Neoplasias/terapiaRESUMO
Body composition assessment (ie, the measurement of muscle and adiposity) impacts several cancer-related outcomes including treatment-related toxicities, treatment responses, complications, and prognosis. Traditional modalities for body composition measurement include body mass index, body circumference, skinfold thickness, and bioelectrical impedance analysis; advanced imaging modalities include dual energy x-ray absorptiometry, computerized tomography, magnetic resonance imaging, and positron emission tomography. Each modality has its advantages and disadvantages, thus requiring an individualized approach in identifying the most appropriate measure for specific clinical or research situations. Advancements in imaging approaches have led to an abundance of available data, however, the lack of standardized thresholds for classification of abnormal muscle mass or adiposity has been a barrier to adopting these measurements widely in research and clinical care. In this review, we discuss the different modalities in detail and provide guidance on their unique opportunities and challenges.
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Composição Corporal , Neoplasias , Humanos , Neoplasias/diagnóstico por imagem , Índice de Massa Corporal , Dobras Cutâneas , Impedância Elétrica , Absorciometria de Fóton , Tomógrafos Computadorizados , Imageamento por Ressonância Magnética , Tomografia por Emissão de PósitronsRESUMO
CONTEXT: Ramadan fasting (RF) is associated with various physiological and metabolic changes among fasting Muslims. However, it remains unclear whether these effects are attributable to changes in meal timing or changes in dietary energy and macronutrient intakes. Furthermore, the literature on the associations between RF, meal timing, and energy and macronutrient intakes is inconclusive. OBJECTIVES: This systematic review aimed to estimate the effect sizes of RF on energy and macronutrient intakes (carbohydrates, protein, fats, dietary fiber, and water) and determine the effect of different moderators on the examined outcomes. DATA SOURCES: The Cochrane, CINAHL, EMBASE, EBSCOhost, Google Scholar, PubMed/MEDLINE, ProQuest Medical, Scopus, ScienceDirect, and Web of Science databases were searched from inception to January 31, 2022. DATA EXTRACTION: The studies that assessed energy, carbohydrate, protein, fat, fiber, and water intakes pre- and post-fasting were extracted. DATA ANALYSIS: Of the 4776 identified studies, 85 relevant studies (n = 4594 participants aged 9-85 y) were selected. The effect sizes for the studied variables were as follows: energy (number of studies [K] = 80, n = 3343 participants; mean difference [MD]: -142.45; 95% confidence interval [CI]: -215.19, -69.71), carbohydrates (K = 75, n = 3111; MD: -23.90; 95% CI: -36.42, -11.38), protein (K = 74, n = 3108; MD: -4.21; 95% CI: -7.34, -1.07), fats (K = 73, n = 3058; MD: -2.03; 95% CI: -5.73, 1.67), fiber (K = 16, n = 1198; MD: 0.47; 95% CI: -1.44, 2.39), and water (K = 17, n = 772; MD: -350.80; 95% CI: -618.09, 83.50). Subgroup analyses showed age significantly moderated the 6 dietary outcomes, and physical activity significantly moderated water intake. There were significant reductions in energy, carbohydrate, and protein intakes during RF. CONCLUSIONS: The change in meal timing rather than quantitative dietary intake may explain various physiological and health effects associated with RF.
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Importance: Consuming a whole food plant-based diet (WFPBD) is a promising, low-risk strategy for reducing risk of prevalent chronic disease and certain cancers, with synergistic benefits for climate and environment. However, few US adults report consuming a WFPBD. Understanding the reasons for this inconsistency is important for developing and implementing interventions for promoting a WFPBD. However, no research to elucidate decisional balance driving current consumption patterns in the US exists. Objective: This research aims to validate an online survey to assess decisional balance for the consumption of a WFPBD, describe attitudes and beliefs toward adopting a WFPBD, and evaluate socio-demographic differences in decisional balance for consuming a WFPBD among a convenience sample of US adults. Design: Online cross-sectional data collection followed by confirmatory factor analysis (CFA), validation of internal consistency, and examination of invariance across socio-demographic variables. Sensitivity analysis of full vs. truncated survey to predict self-reported dietary patterns and consumption behaviors were evaluated. Results of the survey and significant differences by socio-demographics were assessed. Setting: Online survey based on previous research, created via Qualtrics, and administered through MTurk. Participants: A total of 412 US adults, majority female (66%), White (75%), 30-60 years old (54%), ≥ Bachelor's degree (85%), and earning ≥ $45K (68%). Main outcomes and measures: Factor loadings, covariance of survey items, associations with self-reported dietary pattern and consumption measures, and differences in pros, cons, and decisional balance across socio-demographic variables. Results: CFA reduced the survey from 49 to 12 items and demonstrated invariance across socio-demographic variables. Pros and cons varied inversely and significantly (cov = -0.59), as expected. Cronbach's α 's for subscales in the final, reduced model were high (>0.80). Pros, cons, and decisional balance in both the full and the reduced model were significantly (p < 0.05) associated with self-reported dietary pattern and consumption. Conclusion and relevance: Our analyses indicate the WFPBD Survey is a parsimonious and psychometrically sound instrument for evaluation of decisional balance to consume a WFPBD diet among our sample of US adults. These results may be instrumental for development and deployment of interventions intended to promote consumption of a WFPBD in the US.
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Intermittent fasting is a popular diet for weight loss, but concerns have been raised regarding the effects of fasting on the reproductive health of women and men. Accordingly, we conducted this literature review to clarify the effects of fasting on reproductive hormone levels in humans. Our results suggest that intermittent fasting decreases androgen markers (i.e., testosterone and the free androgen index (FAI)) while increasing sex hormone-binding globulin (SHBG) levels in premenopausal females with obesity. This effect was more likely to occur when food consumption was confined to earlier in the day (eating all food before 4 pm). In contrast, fasting did not have any effect on estrogen, gonadotropins, or prolactin levels in women. As for men, intermittent fasting reduced testosterone levels in lean, physically active, young males, but it did not affect SHBG concentrations. Interestingly, muscle mass and muscular strength were not negatively affected by these reductions in testosterone. In interpreting these findings, it is important to note that very few studies have been conducted on this topic. Thus, it is difficult to draw solid conclusions at present. From the limited data presented here, it is possible that intermittent fasting may decrease androgen markers in both genders. If this is the case, these results would have varied health implications. On the one hand, fasting may prove to be a valuable tool for treating hyperandrogenism in females with polycystic ovarian syndrome (PCOS) by improving menstruation and fertility. On the other hand, fasting may be shown to decrease androgens among males, which could negatively affect metabolic health and libido. More research is warranted to confirm these preliminary findings.
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Hiperandrogenismo , Síndrome do Ovário Policístico , Androgênios , Índice de Massa Corporal , Jejum , Feminino , Humanos , Masculino , Síndrome do Ovário Policístico/metabolismo , TestosteronaRESUMO
BACKGROUND: Time restricted feeding (TRF) involves confining the eating window to a specific number of hours, and fasting for the remaining hours of the day. OBJECTIVE: This study examined if changes in body weight and metabolic risk factors during TRF, differ between premenopausal and postmenopausal women. METHODS: This is a secondary analysis of an 8-week TRF study (4-6 h eating window, 18-20 h fasting window daily) conducted in adults with obesity. Male participants were excluded, and female subjects were classified in two groups based on menstrual status: premenopausal (n = 13), or postmenopausal (n = 19). Perimenopausal women were excluded from the original study. RESULTS: Body weight decreased by week 8 in premenopausal women (-3.3 ± 0.4%) and postmenopausal women (-3.3 ± 0.5%) (main effect of time, P < 0.001), with no difference between groups (no group × time interaction). Adherence was excellent in both groups, with premenopausal women adhering to their prescribed eating window on 6.2 ± 0.1 d/week, and postmenopausal women adhering to their window on 6.2 ± 0.2 d/week. Fat mass, lean mass, fasting insulin, insulin resistance, and 8-isoprostane (marker of oxidative stress) were reduced similarly in both groups (main effect of time, P < 0.05 for all comparisons). Visceral fat mass, relative skeletal muscle index (RSMI), blood pressure, LDL cholesterol, HDL cholesterol, triglycerides, fasting glucose, HbA1c, TNF-alpha and IL-6 remained unchanged in both groups by week 8. CONCLUSION: These findings suggest that the weight loss and metabolic benefits of TRF do not differ between premenopausal and postmenopausal women with obesity.
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Jejum , Resistência à Insulina , Índice de Massa Corporal , Peso Corporal , Feminino , Humanos , Masculino , Pós-Menopausa , Pré-MenopausaRESUMO
Background: Alternate day fasting combined with a low carbohydrate diet (ADF-LC) is an effective weight loss regimen. Whether the weight loss induced by ADF-LC can improve sleep, remains unknown. Objective: This study examined the effect an ADF-LC diet on sleep quality, duration, insomnia severity and the risk of obstructive sleep apnea. Methods: Adults with obesity (n = 31) participated in ADF (600 kcal "fast day"; ad libitum intake "feast day") with a low-carbohydrate diet (30% carbohydrates, 35% protein, and 35% fat). The 6-month trial consisted of a 3-month weight loss period followed by a 3-month weight maintenance period. Results: Reductions in body weight (-5 ± 1 kg, p < 0.001) and fat mass (-4 ± 1 kg, p < 0.01) were noted during the weight loss period, and these reductions were sustained during the weight maintenance period. Lean mass and visceral fat remained unchanged. The Pittsburgh Sleep Quality Index (PSQI) score indicated poor sleep quality at baseline (6.4 ± 0.7) with no change by month 3 or 6, versus baseline. ISI score indicated subthreshold insomnia at baseline (8.5 ± 1.0), with no change by month 3 or 6, versus baseline. The percent of subjects with high risk of obstructive sleep apnea at baseline was 45%, with no change by month 3 or 6. Wake time, bedtime, and sleep duration remained unchanged. Conclusion: The ADF-LC diet does not impact sleep quality, duration, insomnia severity or the risk of obstructive sleep apnea in adults with obesity.
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Dieta com Restrição de Carboidratos , Jejum , Obesidade/complicações , Apneia Obstrutiva do Sono/etiologia , Distúrbios do Início e da Manutenção do Sono/etiologia , Sono , Adolescente , Adulto , Idoso , Composição Corporal , Peso Corporal , Suscetibilidade a Doenças , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Medição de Risco , Fatores de Risco , Apneia Obstrutiva do Sono/metabolismo , Distúrbios do Início e da Manutenção do Sono/metabolismo , Fatores de Tempo , Redução de Peso , Adulto JovemRESUMO
OBJECTIVE: Alternate day fasting (ADF) has been shown to lower body weight and improve subjective appetite by increasing fullness. What remains unknown, however, is whether carbohydrate restriction during ADF would provide additional weight loss benefits by helping to lower hunger as well. Accordingly, this study examined the effect of 6-months of ADF combined with a low carbohydrate diet on fasting and postprandial appetite ratings. METHODS: Adults with obesity (n = 31) participated in ADF (600 kcal "fast day" alternated with an ad libitum "feast day") with a low-carbohydrate background diet (30% carbohydrates, 35% protein, and 35% fat). The 6-month trial consisted of a 3-month weight loss period followed by a 3-month weight maintenance period. RESULTS: After 6-months of an ADF-low carbohydrate diet, body weight decreased (P < 0.01) by 6.2 ± 1.0 kg, relative to baseline. Subjective hunger and fullness did not change throughout the study. Fasting insulin decreased (P < 0.05) by 3.3 ± 1.3 µlU/mL by month 6, relative to baseline. Fasting glucose and insulin resistance, remained unchanged over the course of the study. Hunger and fullness were not related to body weight, glucoregulatory factors or energy intake. CONCLUSIONS: These findings suggest that ADF combined with a low carbohydrate diet is not associated with any changes in appetite, relative to baseline. TRIAL REGISTRATION: Clinicaltrials.gov, NCT03528317.
Assuntos
Apetite , Jejum , Adulto , Dieta com Restrição de Carboidratos , Humanos , Obesidade , Redução de PesoRESUMO
This study compared the weight loss efficacy of alternate-day fasting (ADF) versus daily calorie restriction (CR) in adults with subclinical hypothyroidism. After 6 months, body weight decreased (P < 0.001) similarly by ADF (-7% ± 1%) and CR (-8% ± 2%). Insulin resistance decreased (P < 0.05) more by ADF versus CR. Free thyroxin and thyroid-stimulating hormone remained unchanged. Thus, ADF and CR produce similar weight loss in this population, without affecting thyroid hormone levels. Novelty Intermittent fasting and daily restriction produce similar reductions in body weight in subjects with subclinical hypothyroidism.