Eating time variation from weekdays to weekends and its association with dietary intake and BMI in different chronotypes: findings from National Health and Nutrition Examination Survey (NHANES) 2017-2018.

Evidence suggests that differences in meal timing between weekends and weekdays can disrupt the body's circadian rhythm, leading to a higher BMI. We aimed to investigate the associations between mealtime variation from weekdays to weekends (eating midpoint jetlag), dietary intake and anthropometric parameters, based on individuals' chronotype. The study utilised data from National Health and Nutrition Examination Survey 2017-2018. Food consumption was estimated by weighted average of participants' food intake on weekdays and weekends. Eating midpoint jetlag, defined as the difference between the midpoint of the first and last mealtimes on weekends and weekdays, was calculated. Chronotype was assessed by participants' mid-sleep time on weekends, adjusted for sleep debt. Linear regression analysis was conducted to investigate the associations between variables. The sample was categorised into chronotype tertiles. Among individuals in the third chronotype tertile, there was a positive association between eating midpoint jetlag and BMI (ß = 1·2; 95 % CI (1·13, 1·27)). Individuals in the first tertile showed a positive association between eating midpoint jetlag and energy (ß = 96·9; 95 % CI (92·9, 101·7)), carbohydrate (ß = 11·96; 95 % CI (11·2, 12·6)), fat (ß = 3·69; 95 % CI (3·4, 3·8)), cholesterol (ß = 32·75; 95 % CI (30·9, 34·6)) and sugar (ß = 8·84; 95 % CI (8·3, 9·3)) intake on weekends. Among individuals with an evening tendency, delaying meals on weekends appears to be linked to a higher BMI. Conversely, among individuals with a morning tendency, eating meals later on weekends is associated with higher energetic intake on weekends.

Association between sleep duration and quality with food intake, chrononutrition patterns, and weight gain during pregnancy.

To analyse the association between sleep duration and quality with food intake, chrononutrition patterns, and weight gain during pregnancy. A prospective cohort study was conducted with 100 pregnant women. Data collection occurred once during each gestational trimester. The assessment of sleep quality and duration was performed using the Pittsburgh Sleep Quality Index. Food intake was assessed using three 24-h recalls in each trimester. Body weight was measured during the three trimesters, and height was measured only once to calculate the BMI. Linear regression analyses were performed to associate sleep duration and quality with food consumption and weight gain variables. Longer sleep duration was associated with a later dinner in the first trimester (ß = 0·228, P = 0·025) and earlier in the third trimester (ß = -0·223, P = 0·026), in addition to a later morning snack in the second trimester (ß = 0·315, P = 0·026). Worse sleep quality was associated with higher total energy intake (ß = 0·243, P = 0·044), total fat (ß = 0·291, P = 0·015) and the chrononutrition variables such as a higher number of meals (ß = 0·252, P = 0·037), higher energetic midpoint (ß = 0·243, P = 0·044) and shorter fasting time (ß = -0·255, P = 0·034) in the third trimester. Sleep quality was also associated with a higher BMI in the first trimester of pregnancy (ß = 0·420, P = < 0·001). Most of the associations found in the present study show that poor sleep is associated with higher energy and fat intake and higher BMI. Longer sleep duration was associated with a later dinner in early pregnancy and an earlier dinner in late pregnancy, as well as with a later morning snack in the second trimester of pregnancy.

Meal timing variability of rotating shift workers throughout a complete shift cycle and its effect on daily energy and macronutrient intake: a field study.

PURPOSE: To evaluate the meal timing variability of rotating shift workers throughout a complete shift schedule and its effect on daily energy and macronutrient intake. METHODS: Thirty male shift-workers from a mining company were evaluated in a complete rotation shift cycle over 240 consecutive hours (10 days; two days of morning shifts, two days of evening shifts, 24 h free, two days of night shifts and three days off). Food intake related variables [meal timing, energy (kcal) and macronutrient intake (%)] were assessed by 24 h recall by a trained nutritionist. Mixed models were used to analyze the variation in meal timing and energy and macronutrient intake throughout the shift cycle, as well as the interaction between shift and time ranges (00:00-03:59, 04:00-07:59, 08:00-11:59, 12:00-15:59, 16:00-19:59, 20:00-23:59). RESULTS: The first meal of the day was earlier on night shifts [D6 (3:44 ± 0:33) and D7 (5:52 ± 0:42)] compared to the other shifts (p < 0.001), except for D4 (evening shift; 5:51 ± 0:47) versus D7 (p = 0.999). Night shifts also showed a shorter night fasting (D5-D6, 9.3 h; D6-D7, 9.6 h) than most other nights (p < 0.05), except for the fasting between D1-D2 (11.3 h) and D3-D4 (11.2 h) (p > 0.05). There was no difference in 24 h energy intake throughout the shift cycle (p = 0.065). The analysis of interaction between shift and time ranges showed that night shift (D6) presented a higher intake of energy (441.5 ± 48.4 kcal), percentage of energy (D6: 17.8 ± 1.8%), fat (17.6 ± 2.0%), carbohydrate (17.0 ± 1.7%) and protein (16.4 ± 1.8%) between 00:00 and 03:59 compared with the other shift days (p < 0.05). CONCLUSION: Night shifts seem to contribute to a longer eating window than other shifts. Moreover, there is a higher energy and macronutrients intake during night shifts, which reduces the night fast period and could have implications for metabolic dysregulation.

Influence of fasting during the night shift on next day eating behavior, hunger, and glucose and insulin levels: a randomized, three-condition, crossover trial.

AIMS: To investigate the influence of fasting during the night shift on eating behavior, hunger, glucose and insulin levels the following day. METHODS: Study with 10 male police officers who have been working at night. Participants were tested under three different conditions separated by at least 6 days of washout in a randomized, crossover design: "Night Shift Fasting" (NSF)-two nights of fasting during the night shift; "Night Shift Eating" (NSE)-two nights with the consumption of a standardized meal during the night shift (678 ± 42 kcal consumed at ~ 0200 h); and "Nighttime Sleep" (NS)-two nights of sleep. The morning after, blood glucose and insulin and hunger ratings were assessed, and food intake was assessed with an ad libitum test meal. Food intake was also assessed throughout the remainder of the day using a food record. Generalized Estimating Equations were used to analyze the effect of experimental condition. RESULTS: Food intake during the test meal, especially of proteins and fats, was higher after fasting during the night shift compared to the other conditions (p < 0.05), whereas desire to eat scores were lower after the NSF compared to NSE condition (p = 0.043). Hunger levels were lower after the NSF compared to the NS condition (p = 0.012). Insulin and HOMA-IR were also lower in the morning after NSF (p < 0.001). CONCLUSION: Fasting during the night shift leads to not only a higher intake of energy and macronutrients both in the early morning after work and throughout the next day, but also lower insulin levels and HOMA-IR in the morning. REGISTRATION NUMBER OF CLINICAL TRIAL: NCT03800732. Initial release: 01/09/2019. Last release: 02/23/2022.

Eating Duration throughout a Rotating Shift Schedule: A Case Study.

OBJECTIVE: The impact of the rotation between different shifts and free days within a short period of time on the food consumption is poorly addressed in the literature. Our objective was to characterize the eating duration (ED) over 10 d of clockwise rotating and to associate it with the intake of energy and macronutrients. METHODS: Thirty male shift-workers from a mining company were evaluated over a complete rotation shift schedule of 10 consecutive days (2 d of morning shifts, 2 d of afternoon shifts, 24 h free-day, 2 d of night shifts, and three free days). ED was defined as the interval between the first meal after awaking and last meal before sleep onset. Sleep/wake periods and food intake were evaluated by actigraphy and 24 h recalls, respectively. Generalized models were used to analyze the variation in ED and its association with nutrient intake over the shift schedule. RESULTS: ED periods showed significant variations throughout shift rotation and were associated with energy intake. The highest energy intake (3410 ± 235 kcal) and longest ED (20.7 ± 1.2 h) were found on Day 5, the day between afternoon and night shifts, and a part of Day 6 (night shift), i.e., in the longest period of wakefulness and the shortest sleep duration (4.7 ± 0.3 h) (p < 0.05 for all). The lowest energy intake (1284 ± 125 kcal) and shortest ED (4.96 ± 0.7 h) (p < 0.05) occurred after the last night shift (Day 7). The balance between the percentage of macronutrients did not differ statistically between the ED periods. CONCLUSIONS: In general, longer periods of wakefulness showed greater energy intake, demonstrating the tendency of workers to eat around the clock during their shift. Even with the energy intake variation, the balance of macronutrients remained the same over the ED periods. Despite the need of confirmation in future studies, these results suggest that the management of ED period could be considered in the nutritional approach of shift workers.

Effects of timing of food intake on eating patterns, diet quality and weight gain during pregnancy.

Studies have suggested that meal timing plays a role in nutritional health, but this subject has not been sufficiently studied in pregnant women. We analysed the effect that timing of food intake has on eating patterns, diet quality and weight gain in a prospective cohort study with 100 pregnant women. Data were collected once per trimester: 4th-12th, 20th-26th and 30th-37th weeks. Food intake was evaluated using three 24-h dietary recalls, which were used to assess eating patterns and diet quality. Distribution of energy and macronutrient intake throughout the day was considered eating patterns. Diet quality was assessed using the Brazilian Healthy Eating Index-Revised. Weight gain was evaluated during each trimester. Women were classified as early or late timing of the first and last eating episodes if these values were below or above the median of the population, respectively (first eating episode = 08.38 hours; last eating episode = 20.20 hours). Generalised estimating equation models adjusted for confounders were used to determine the effects of timing of the first and last eating episodes (groups) and gestational trimesters (time) (independent variable) on eating patterns, diet quality and weight gain (dependent variables). Early eaters of the first eating episode have a higher percentage of energy and carbohydrate intake in morning and a lower at evening meals. They also have a better diet quality for fruit components when compared with late eaters of the first eating episode. Our results emphasise the importance of considering meal timing in the nutritional antenatal guidelines to promote maternal-fetal health.

The impact of a higher eating frequency on the diet quality and nutritional status of women with breast cancer undergoing chemotherapy.

The present study investigated the association between eating frequency (EF), diet quality and nutritional status of fifty-five women with breast cancer (BC) undergoing chemotherapy (CT), with three follow-ups, before the first cycle (T0), after the intermediate cycle (T1) and after the last cycle of CT (T2). Dietary data were obtained by nine 24-h dietary recalls (24HR), and the Brazilian Healthy Eating Index Revised (BHEI-R) was used for qualitative analysis of diet. The average EF was established by adding the number of daily eating episodes in the three 24HR of each time. Anthropometric variables were obtained at three times. Women who reported higher EF (equal to or above median value (T0 and T1: 4·67; T2: 4·33 eating episodes)) presented better anthropometric parameters, in T0 and T1, as well as higher scores for BHEI-R specific groups and BHEI-R Total score in T1 and T2. In generalised linear models, the continuous variable EF was negatively associated with all the anthropometric variables in T0 and with the waist:height ratio in T1. There were positive associations for the BHEI-R groups at the three times: Total Fruit; Whole Fruit; Total Vegetables; Dark Green and Orange Vegetables and Legumes. At T1 and T2 the EF was positively associated with the BHEI-R Total score, and also with Whole Grains in T1. The results suggest that a higher EF was associated with a better diet quality during CT in women with BC. In contrast, an inverse association was observed between EF and anthropometric parameters before the first cycle of treatment.

The association between anxiety, hunger, the enjoyment of eating foods and the satiety after food intake in individuals working a night shift compared with after taking a nocturnal sleep: A prospective and observational study.

Subjective responses to meals are altered by shortened sleep time and anxiety state, but this effect has been poorly studied in shift workers - who act as a typical model concerning sleep restriction and present high levels of anxiety. The objective of this study was to compare subjective perceptions of meals and the levels of anxiety in the same subjects after working night shifts and after taking a nocturnal sleep, and to investigate associations between the responses to meals and the levels of anxiety under these two conditions. The study evaluated 34 male permanent night-shift workers who worked a 12-h shift followed by a 36-h rest period. Evaluations included: sleep pattern (on three days after working night shifts and after sleeping at night); hunger, enjoyment of eating foods and satiety after a meal (evaluated by visual analogue scales on three non-consecutive days after working night shifts and after nocturnal sleeps); and state of anxiety (on a day after working a night shift and a day after a nocturnal sleep). In the days following a night shift, workers had higher mean hunger scores before lunch and higher anxiety scores than when they had slept at night (p = 0.007 and 0.001, respectively). Linear regression indicated that, after a night shift, anxiety scores were negatively associated with hunger before breakfast (p = 0.04) and lunch (p = 0.03), the enjoyment of eating foods (p = 0.03) and the number of meals eaten during the course of the 24 h (p = 0.03). It is concluded that night shifts increase mean hunger and anxiety scores. Anxiety levels seem to interfere with the responses associated with food consumption.

Obesity and sleepiness in women with fibromyalgia.

Fibromyalgia (FM) is associated with a number of comorbidities, including chronic widespread pain, fatigue and non-restorative sleep. Evidence has shown that FM is closely associated with overweight and obesity. The objective of the present study was to investigate the relationship between obesity and sleepiness in women with FM. A total of 100 adult female patients with a prior medical diagnosis of FM participated in the study. Body mass, height and waist circumference were measured, and body mass index (BMI) was calculated. The diet quality was evaluated by the Healthy Eating Index. Subjective analyses of daytime sleepiness [Epworth Sleepiness Scale (ESS)] and sleep quality (Pittsburgh Sleep Quality) were performed. An obesity rate of 41 % was found in all women (56.1 % were sleepy and 43.9 % were not, p = 0.04). Obese women showed a greater level of sleepiness when compared with non-obese (10.2 and 7.0, respectively, p = 0.004). Sleepy women showed a greater weight gain after the diagnosis of FM when compared with non-sleepy women (11.7 and 6.4 kg, respectively, p = 0.04). A positive and significant correlation between BMI and sleepiness (r = 0.35, p = 0.02) was also found. In multivariate logistic regression, moderate or severe sleepiness (ESS >12) was associated with obesity (odds ratio 3.44, 95 % CI 1.31-9.01, p = 0.04). These results demonstrate an important association between sleepiness and FM, suggesting that the occurrence of obesity may be involved with sleepiness in these patients.

Is the Caloric Midpoint Associated with Food Cravings and Food Intake in Pregnant Women?

Objective: The field of chrononutrition suggests that mealtime can influence food intake. Previous studies have linked the caloric midpoint - defined as the time at which 50% of the daily energy is consumed - with different aspects of food consumption. However, its relationship with food craving remains unexplored. This cross-sectional study aimed to investigate the association between caloric midpoint, food craving, and food consumption in pregnant women.Methods: The study comprised 233 pregnant women classified as early eaters (caloric midpoint ≤ 1:00pm) and late eaters (caloric midpoint >1:00pm). Food craving were assessed using Food Craving Trait and State Questionnaires. Energy and nutrient intake, as well as mealtimes, were assessed using a 24-h food recall.Results: No association between caloric midpoint and food craving was found. However, late eaters consumed more calories (2039.47 kcal vs 1843.44 kcal; p < 0.001), carbohydrates (255.06 g vs 211.12 g; p = 0.002), total fat (73.1 g vs 64.8 g; p = 0.003), monounsaturated fat (21.33 mg vs 18.59 mg; p = 0.002) and saturated fat (24.37 mg vs 22.21 mh; p = 0.01) and had higher consumption of calories and macronutrients in the first (calories: 275.63 vs 213.41, p = 0.007; carbohydrate: 170.42 vs 142.54, p = 0.01; total fat: 56.49 vs 50.17, p = 0.04) and second (calories: 213.21 vs 151.59, p = 0.04; carbohydrate: 130.44 vs 96.6, p = 0.04; protein: 15.17 vs 13.71, p = 0.03) afternoon snack, dinner (calories: 576.89 vs 412.4, p < 0.001; carbohydrate: 230.76 vs 169.45, p < 0.001; protein: 80.48 vs 68.9, p = 0.02; total fat: 212.77 vs 147.12, p < 0.001) and late-night snack (calories: 135.75 vs 68.3, p = 0.04; total fat: 13.23 vs 22.45, p = 0.04) than early eaters.Conclusion: Pregnant women who concentrate their meals at later times consumed more calories, macro and micronutrients throughout the day and in the night meals when compared to early eaters.

Lifestyle, meal times, and sleep patterns changes in higher education professors during COVID-19: Association with non-communicable chronic diseases.

BACKGROUND: In response to the COVID-19 pandemic, educational institutions had to swiftly adapt and transition to remote teaching in order to maintain academic activities. However, these changes presented a number of challenges for professors, which could have negative effects on their health. OBJECTIVE: To analyze the association between changes in dietary and sleep habits, physical activity level, and sedentary behavior with the development of non-communicable diseases (NCDs) among Brazilian higher education professors during the pandemic period. METHODS: This is a cross-sectional and retrospective study conducted using an online form. Generalized linear models, adjusted for age, sex, and body mass index, were used to verify the difference between pre-pandemic and pandemic periods. Logistic regression models were used to predict the odds ratio (OR) for the development of NCDs according to physical activity time, sedentary behavior time, dietary and sleep patterns. RESULTS: A total of 936 professors residing across Brazil participated in the survey. The duration of sedentary behavior increased, sleep duration slightly decreased, and meal times shifted to earlier during the pandemic. A total of 22.9%of the participants reported the diagnosis of some NCDs during this period. Physical activity practice was associated with a lower risk of diseases during the pandemic, regardless of the intensity performed. On the other hand, late eating habits and excessive food consumption during the pandemic were associated with a higher risk. CONCLUSION: The results provide data that can help in the development of public policies that promote health actions to minimize the consequences associated with the pandemic period.

Seasonal and Regional Differences in Eating Times in a Representative Sample of the Brazilian Population.

Human food intake and its timing are a complex behavior that can be influenced by a variety of factors, some of which may vary from season to season or from region to region. In this study, our aim was to investigate the seasonal variation in food intake times, with a particular focus on how these may vary across different regions of a country. We conducted an analysis of data from 20,622 adults from the National Household Budget Survey (POF-IBGE), encompassing complete food diaries collected from individuals residing in Brazil, and thereby ensuring representation across different latitudes. Each participant's daily food intake was reported for two non-consecutive days at different times in the same week using food diaries. An ANOVA revealed a later food intake time in the evening in high-latitude regions compared to low-latitude regions. The Sidak post-hoc test showed a significant interaction effect between region and season, demonstrating a pattern of early First Intake Time and Eating Midpoint in the Northeast region during spring/summer. Additionally, we observed an independent effect of the region, as early food intake times were found in low-latitude regions. These findings offer a basis for discussing food intake times among individuals living in different regions located on distinct latitudes.

Is Evening Carbohydrate Intake in Healthy Individuals Associated with Higher Postprandial Glycemia and Insulinemia When Compared to Morning Intake? A Systematic Review and Meta-Analysis of Randomized Crossover Studies.

This systematic review aimed to summarize randomized clinical trials that compared the postprandial glycemic and insulinemic metabolic response after eating isocaloric and standardized carbohydrate meals consumed at two moments: morning versus night, in healthy individuals who were not shift workers. The search strategy consisted of an electronic search using the following electronic databases: MEDLINE (via PubMed), EMBASE (via Elsevier), LILACs (Virtual Health Library - VHL), Cochrane Registers of Clinical Trials (CENTRAL, via Wiley) and gray literature (Opengray.eu). The PICO strategy was used to define the search terms (P: healthy adults, I: nocturnal intake, C: morning intake, O: area under the curve (AUC) of the postprandial glucose and insulin response). This review was reported according to the PRISMA statement. From the 3757 articles found, 412 were duplicates and excluded, totaling 3345 that had their titles and abstracts read. A total of 42 articles met the inclusion criteria and were read in full, and eight studies were included in the systematic review. The certainty of the evidence was assessed using GRADE. The results showed, with moderate quality of evidence, a postprandial response with higher glycemic values in the evening compared to the morning (SMD = 1.30; 95% CI, 1.01 to 1.59; I2 = 0%; p < 0.00001; 8 studies and 116 participants). No differences were found between insulin values at night and in the morning (SMD = 0.19; 95% CI, -0.10 to 0.49; 6 studies and 90 participants). We concluded that the intake of carbohydrates at night leads to higher glycemic, but not insulinemic, postprandial values. Revision Record: PROSPERO number CRD42019137862 available at: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42019137862 Key teaching points and nutritional relevanceThis systematic review summarized randomized clinical trials that compared the postprandial glycemic and insulinemic response after eating carbohydrate meals in the morning versus at night.A total of eight studies were included in the systematic review; the results showed a postprandial response with higher glycemic values in the evening compared to the morning.No differences were found between insulin values at night and in the morning;• The intake of carbohydrates at night leads to higher glycemic, but not insulinemic, postprandial values.

Late meal intake is associated with abdominal obesity and metabolic disorders related to metabolic syndrome: A chrononutrition approach using data from NHANES 2015-2018.

BACKGROUND & AIMS: Chrononutrition is an emerging area that suggests that late eating time is associated with poor nutritional and metabolic outcomes. However, epidemiological studies are scarce on this topic. The aim of this study was to characterize the chrononutrition patterns in a large and representative US population (NHANES 2015-2016 and 2017-2018) of adults and elderly and investigate their association with obesity and metabolic disorders that make up the metabolic syndrome. METHODS: A total of 7379 adults and elderly individuals were included in the analysis. Meal timing data were collected through two 24-h dietary recalls in both cycles. Poisson regression adjusted for confounders was used to evaluate the association between chrononutrition variables (eating duration and tertiles of first and last meal timing, eating midpoint and eating occasions) and obesity, abdominal obesity and metabolic parameters from metabolic syndrome. RESULTS: Adults with a longer eating duration (>12 h) had a higher prevalence of abdominal obesity (IRR, 1.15; 95% CI, 1.03-1.28) when compared with those who ate their meals in a shorter eating duration (≤12 h). In addition, adults in the third tertile of the time of the last meal (mean 22:03) had a higher prevalence of abdominal obesity (IRR, 1.12; 95% CI, 1.01-1.25) compared to first tertile. Adults with later eating midpoints (second and third tertile) had a higher prevalence of elevated fasting glucose (IRR, 1.30; 95% CI, 1.07-1.59 and IRR, 1.65; 95% CI, 1.22-2.22, respectively). Among the elderly, participants with a longer eating duration (>12 h) had a higher prevalence of elevated triglycerides (IRR, 2.74; 95% CI, 1.25-5.96) when compared with those elderly who ate their meals in a shorter eating duration (≤12 h). CONCLUSION: These findings suggest that a long eating duration and late first and last meal timing are chrononutrition patterns associated with cardiometabolic risks in free-living Americans.

Impact of Nighttime Food Consumption and Feasibility of Fasting during Night Work: A Narrative Review.

Shift work has been associated with an increased risk of developing chronic non-communicable diseases, such as obesity. The reduction in overnight fasting and its physiological consequences seem to affect the metabolic health of shift workers, but little has been discussed regarding the feasibility and implications of maintaining a night-long fast during work. This narrative review aims to discuss the impact of eating behavior on the reduction of overnight fasting in shift workers, as well as possible nutritional strategies involving fasting that have been tested for shift workers, to contribute to the establishment of nutritional guidelines for them. We used various databases and search engines to retrieve relevant articles, reviews, and investigations. Despite the potential benefits of overnight fasting for other groups, few studies have investigated this approach in the context of shift work. Generally, it seems to be a feasible and metabolically beneficial strategy for shift workers. However, it is essential to investigate the potential risks and benefits of reducing the fasting time for shift workers, considering social, hedonic, and stress-related factors. Furthermore, randomized clinical trials are necessary to establish safe and feasible strategies for shift workers to practice different fasting windows.

Time-Related Eating Patterns Are Associated with the Total Daily Intake of Calories and Macronutrients in Day and Night Shift Workers.

The aim of the study was to investigate whether time-related eating patterns are associated with the daily intake of calories and macronutrients in Brazilian male military police officers (n = 81; 29-day and 52-night workers; mean age: 36.4 ± 0.9 and 38.5 ± 0.7 years, respectively). Energy and macronutrient intake were determined by a non-consecutive 3-day food recall. Time-related eating patterns, such as the time of the first and the last meals, eating duration, and caloric midpoint, were evaluated. Individuals were classified as "early" or "late" eaters according to the median caloric midpoint. Night shift workers showed a later eating time for the last meal (p < 0.001), longer eating duration (p < 0.001), and later caloric midpoint (p = 0.037) than day workers. Late eaters from both workgroups consumed more 24 h energy (p = 0.028), fat in calories (p = 0.006) and protein (calories: p < 0.001; percentage of total calories: p = 0.042), and less carbohydrates in calories (p = 0.010) intake than early eaters. The time of the first meal was negatively correlated with 24 h energy (p = 0.024) and carbohydrate (p = 0.031) intake only in day workers. The time of the last meal was positively correlated with 24 h energy (day workers: ß = 0.352; p = 0.044; night workers: ß = 0.424; p = 0.002) and protein (day workers: ß = 0.451; p = 0.013; night workers: ß = 0.536; p < 0.001) intake for both shift workers, and with carbohydrate (ß = 0.346; p = 0.016) and fat (ß = 0.286; p = 0.042) intake only in night workers. Eating duration was positively correlated with energy (day workers: ß = 0.473; p = 0.004; night workers: ß = 0.320; p = 0.023) and carbohydrate (day workers: ß = 0.418; p = 0.011; night workers: ß = 0.364; p = 0.010) intake in both groups. Thus, time-related eating patterns indicative of intake later at night are associated with increased daily energy and macronutrient intake.

Is self-reported short sleep duration associated with obesity? A systematic review and meta-analysis of cohort studies.

CONTEXT: A possible association between self-reported short sleep duration and risk of obesity has been studied. OBJECTIVE: To analyze the association between sleep duration and obesity. METHODS: The LILACS, Medline, Central, Embase, and OpenGrey databases were searched from inception until July 2020. Two authors screened the studies independently according to the PECO strategy, as follows: participants: > 18 years old; exposure: short sleep duration; control: regular sleep; outcome: obesity). Only cohort studies were included. A total of 3286 studies were retrieved with the search strategy, but only 36 were included. Disagreements were resolved by a third author. The quality of studies was assessed with Newcastle-Ottawa Quality Assessment Form for Cohort Studies. The certainty of the evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation. RESULTS: Thirty-six studies were included, and 22 contributed quantitative data. Most of the studies (n = 27) assessed sleep by self-report. The meta-analysis showed a significant association between self-reported short sleep and development of obesity, and the chances of developing obesity increased when self-reported sleep duration decreased. CONCLUSIONS: Self-reported short sleep was significantly associated with a higher incidence of obesity, with moderate quality of evidence. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42019130143.

The Effect of Exogenous Melatonin on Eating Habits of Female Night Workers with Excessive Weight.

BACKGROUND AND AIMS: Melatonin is a pineal hormone that plays an important role as an endogenous synchronizer of circadian rhythms and energy metabolism. As this circadian component has been closely related to eating behavior, an important question on this topic would be whether melatonin administration could influence eating habits. However, this topic has been rarely studied in the literature in individuals with excessive weight and chronic circadian misalignment, such as shift workers. Therefore, the present study aims to evaluate the effects of exogenous melatonin administration on the quali/quantitative aspects and temporal distribution of food intake in female night workers with excessive weight (overweight and obesity). An additional aim is to evaluate the association of the referred outcomes with circadian misalignment and chronotype. METHODS: A randomized, double-blind, placebo-controlled, crossover clinical trial was conducted with 27 female nursing professionals with excessive weight who worked permanent night shifts. The protocol was implemented under real-life conditions for 24 weeks, in two randomly allocated conditions (12 weeks of melatonin and 12 weeks of placebo). The quali/quantitative aspects of food intake (NOVA classification, total energy intake and the proportion of calories from macronutrients) and meal timing were assessed using food diaries. Timing for every meal recorded in the diaries was assessed to evaluate the temporal distribution of food intake. Generalized estimating equations were performed for each dependent variable. RESULTS: No significant modifications in total energy intake, macronutrient distribution, types of foods consumed, and meal timing were observed after melatonin administration. Different levels of circadian misalignment and chronotype did not interfere with these results. CONCLUSION: Eating habits of female night workers with excessive weight remained unchanged after melatonin administration, and no association of these results with circadian misalignment and chronotype was found. These results suggest that the metabolic effects of melatonin may occur independently of food intake.

Is chronotype associated with dietary intake and weight gain during pregnancy? A prospective and longitudinal study.

OBJECTIVES: The effects of chronotype on dietary intake and weight gain during pregnancy have not been addressed in the literature. The aim of this study was to analyze the effect of chronotype on eating patterns, energy, and macronutrient intake and distribution, as well as weight gain during pregnancy. METHODS: This was a prospective cohort study carried out with 100 pregnant women in the first, second, and third gestational trimesters. Dietary intake was assessed by three 24-h dietary recalls in each trimester, totaling nine recalls. Energy and macronutrient intake and distribution were evaluated at meals throughout the day. Chronotype was derived from midsleep time on free days, and the scores obtained were categorized into tertiles. Recommendations from the Institute of Medicine were used to assess the adequacy of weight gain. Generalized estimating equation models were used to determine the effects of chronotype and gestational trimester on eating patterns, daily energy, macronutrient distribution, and weight gain. RESULTS: Pregnant women with values for midsleep time on free days indicative of eveningness have breakfast later and also have higher energy and carbohydrate intake at dinner than "morning" women. Pregnant "morning" women showed better diet quality in terms of milk and dairy and saturated fat. Also, despite the tendency for all tertiles to gain excess weight during pregnancy, we found that pregnant women with a tendency to eveningness had worse adequacy of gestational weight gain in the third trimester than "morning" women (2.24 ± 0.25 versus 1.22 ± 0.14, P < 0.001). CONCLUSION: Pregnant women with a tendency to eveningness consume breakfast later in the day and exhibit greater consumption of energy and carbohydrates in the evening, as well as a worse standard of gestational weight gain in the third trimester. Our results emphasize the importance of considering chrononutrition variables in prenatal nutritional guidelines to promote maternal and fetal health.

Social Jetlag Is Associated With Impaired Metabolic Control During a 1-Year Follow-Up.

Previous studies have identified social jetlag (SJL) as a risk factor for non-communicable chronic diseases (NCCDs), but its association with metabolic control over time is unclear in the literature. Therefore, we examined the influence of SJL on metabolic parameters and blood pressure (BP) in patients with NCCDs over a 1-year follow-up. This retrospective, longitudinal study included 625 individuals (age: 56.0 +12.0 years; 76% female) with NCCDs [type 2 diabetes mellitus (TD2), systemic arterial hypertension (SHA), obesity, or dyslipidemia]. SJL was calculated based on the absolute difference between mid-sleep time on weekends and weekdays. Current metabolic parameters and BP of the patients were compared with data from a year prior. Generalized estimating equations (GEE) and multiple linear regression analyses were used to examine the association among SJL, metabolic parameters, and BP. Multiple linear regression analyses adjusted for confounders showed that SJL was positively associated with the delta difference of fasting glucose (ß = 0.11, p = 0.02) and triglyceride levels (ß = 0.09, p = 0.04) among all subjects with NCCDs, and with fasting glucose (ß = 0.30, p = 0.0001) and triglyceride levels (ß = 0.22, p = 0.01) in the TD2 group. GEE analysis demonstrated an isolated effect of SJL on diastolic BP. High SJL impaired clinical and metabolic control in individuals with NCCDs, leading to a worse profile after a 1-year follow-up, particularly among type II diabetics.