Timing of food intake and obesity: A novel association

Eating frequency, timing and duration in relation to cognitive performance and AD biomarkers in adults

BACKGROUND

The potential association between temporal dimensions of eating and cognition/cognitive declines has been poorly investigated so far.

OBJECTIVE

Aim of this study was to examine relationships between eating frequency, timing and time window and cognitive performance and novel Alzheimer's Disease (AD) biomarkers in cognitively healthy and mildly cognitively impaired middle-aged and older adults.

METHODS

Cross-sectional data were derived from the ALBION cohort study, including people ≥40-years old who have a positive family history of cognitive disorder or cognition-related concerns. Cognitive performance was assessed by a battery of neuropsychological tests. Amyloid beta (Αβ42), a biomarker of AD-related pathology, was measured in cerebrospinal fluid (CSF). Eating frequency, timing and the eating time window between the first and the last meal were estimated using time related information recorded in four 24-h recalls.

RESULTS

Study participants had, on average, 5.3±1.2 eating episodes per day, consumed at 8:20±1.3 and 21:14±1.3 hours their first and their last eating episode respectively while their eating time window was 12.9±1.6 hours. Eating frequency, but not eating time window, was positively associated with global cognition, executive and language performance even after controlling for age, sex, education, BMI and Mediterranean diet. Increasing eating frequency by 1 eating episode per day was associated with 0.169 higher global z-score. Furthermore, compared to ≤4, having 5-6 or >6 eating episodes per day was associated with better global and memory z-scores. Time of last eating episode was also positively associated with language performance. No associations were detected between eating frequency, timing and window and AD pathology.

CONCLUSIONS

An eating pattern characterized by less frequent eating and/or by earlier times is present in individuals with worse cognitive performance. Our results shed light on the relevance of temporal eating patterns as potential early markers of behavioral or metabolic changes related to AD pathology.

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 (β = 0·228, P = 0·025) and earlier in the third trimester (β = -0·223, P = 0·026), in addition to a later morning snack in the second trimester (β = 0·315, P = 0·026). Worse sleep quality was associated with higher total energy intake (β = 0·243, P = 0·044), total fat (β = 0·291, P = 0·015) and the chrononutrition variables such as a higher number of meals (β = 0·252, P = 0·037), higher energetic midpoint (β = 0·243, P = 0·044) and shorter fasting time (β = -0·255, P = 0·034) in the third trimester. Sleep quality was also associated with a higher BMI in the first trimester of pregnancy (β = 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.

Chronobiotics, satiety signaling, and clock gene expression interplay

The biological clock regulates the way our body works throughout the day, including releasing hormones and food intake. Disruption of the biological clock (chronodisruption) may deregulate satiety, which is strictly regulated by hormones and neurotransmitters, leading to health problems like obesity. Nowadays, using bioactive compounds as a coadjutant for several pathologies is a common practice. Phenolic compounds and short-chain fatty acids, called "chronobiotics," can modulate diverse mechanisms along the body to exert beneficial effects, including satiety regulation and circadian clock resynchronization; however, the evidence of the interplay between those processes is limited. This review compiles the evidence of natural chronobiotics, mainly polyphenols and short-chain fatty acids that affect the circadian clock mechanism and process modifications in genes or proteins resulting in a signaling chain that modulates satiety hormones or hunger pathways.

Changes in body mass index and its association with socio-demographic characteristics between 2010 and 2016 in Singapore

Background

Epidemiological studies have observed an increase in the prevalence of obesity in both western and Asian countries. This study aims to compare the distribution of body mass index (BMI) in the general population of Singapore between 2010 and 2016, and to explore the socio-demographic risk factors associated with it.

Methods

Data for this study were extracted from two national-wise studies in 2010 and 2016, two population-based, cross-sectional epidemiological studies. BMI cut-off scores were used as an indicator to assess obesity in this study, and the data included in the analysis was self-reported by the respondents.

Results

Overall, the study observed decreasing prevalence in underweight and normal weight categories; and an increasing prevalence in overweight and obesity categories in the Singapore adult population between 2010 and 2016. Age, gender, ethnicity, marital status, and educational level were found to be significantly associated with BMI categories.

Conclusion

The observed increase in the population's BMI between 2010 and 2016 may lead to an increase in the incidence of chronic diseases in Singapore. Our study findings add to the existing local literature and provides data for evidence-based policymaking on health-related interventions and program planning.

Meal timing and its role in obesity and associated diseases

Meal timing emerges as a crucial factor influencing metabolic health that can be explained by the tight interaction between the endogenous circadian clock and metabolic homeostasis. Mistimed food intake, such as delayed or nighttime consumption, leads to desynchronization of the internal circadian clock and is associated with an increased risk for obesity and associated metabolic disturbances such as type 2 diabetes and cardiovascular diseases. Conversely, meal timing aligned with cellular rhythms can optimize the performance of tissues and organs. In this review, we provide an overview of the metabolic effects of meal timing and discuss the underlying mechanisms. Additionally, we explore factors influencing meal timing, including internal determinants such as chronotype and genetics, as well as external influences like social factors, cultural aspects, and work schedules. This review could contribute to defining meal-timing-based recommendations for public health initiatives and developing guidelines for effective lifestyle modifications targeting the prevention and treatment of obesity and associated metabolic diseases. Furthermore, it sheds light on crucial factors that must be considered in the design of future food timing intervention trials.

Kairos study protocol: a multidisciplinary approach to the study of school timing and its effects on health, well-being and students' performance

Recent evidence from chronobiology, chssronomedicine and chronopsychology shows that the organisation of social time (e.g., school schedules) generally does not respect biological time. This raises concerns about the impact of the constant mismatch between students' social and internal body clocks on their health, well-being and academic performance. The present paper describes a protocol used to investigate the problem of (de) synchronisation of biological times (chronotypes) in childhood and youth in relation to school times. It studies the effects of student chronotype vs. school schedule matches/mismatches on health behaviours (e.g., how many hours students sleep, when they sleep, eat, do physical activity, spend time outdoors in daylight) and learning (verbal expression, spatial structuring, operations) and whether alert-fatigue levels mediate this effect alignments/misalignments on learning (verbal expression, spatial structuring, operations) and their mediation by alert-fatigue levels. The novelty of our protocol lies in its multidisciplinary and mixed methodology approach to a relevant and complex issue. It draws on up-to-date knowledge from the areas of biology, medicine, psychology, pedagogy and sociology. The methods employed include a varied repertoire of techniques from hormonal analysis (cortisol and melatonin), continuous activity and light monitoring, self-registration of food intake, sleep timings, exercise and exposure to screens, alongside with systematic application of cognitive performance tests (e.g., memory, reasoning, calculation, attention) and self-reported well-being. This comprehensive and interdisciplinary protocol should support evidence-based education policy measures related to school time organisation. Appropriate and healthier school timetables will contribute to social change, healthier students and with more efficient learning. The results of studies using a similar methodology in other countries would ensure replication and comparability of results and contribute to knowledge to support policy making.

Dietary taste patterns and diet quality of female nurses around the night shift

PURPOSE

Night shift workers are at risk of making poor food choices: e.g. sleep deprivation may lead to higher food intake with innate preferred tastes, such as sweet, savoury and fatty foods. Therefore, better insight in dietary taste patterns of night shift workers may improve the understanding of their food choices.

METHODS

This observational study assessed dietary taste patterns of 120 female night shift working nurses and compared them to 307 women of a reference population. Dietary intake, assessed with 24-h dietary recalls, was combined with a taste intensity database, including taste profiles of 557 foods. The contribution to the daily intake of 6 taste clusters was assessed: fat, neutral, sweet/fat, sweet/sour, salt/umami/fat and bitter.

RESULTS

During night shifts, nurses consumed a significantly higher energy percentage (en%) of 'neutral' (5.9 en%), 'sweet/sour' (8.1 en%) and 'sweet/fat' (6.5 en%) tasting foods and a lower en% of 'fat' (- 17.1 en%) and 'bitter' (- 2.1 en%) tasting foods than outside the night shift. They consumed a larger en% from foods with a 'sweet/sour' (1.9 en%) taste and a lower en% from foods with a 'bitter' (- 2.1 en%) taste than the reference population, irrespective of age, BMI and smoking status. A higher en% and gram% of 'fat' tasting foods and a higher gram% 'fat/salt/umami' tasting foods were associated with lower diet quality.

CONCLUSION

Our results only partly support our hypothesis that nurses would select foods with more innate taste preferences. In addition, fat and savoury tasting foods were negatively associated with their diet quality.

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.

Chrononutrition in type 2 diabetes mellitus and obesity: A narrative review

Chrononutrition is a nutritional regimen that follows our biological clock, marked by the changes in metabolism that occur during the day. This regimen includes the distribution of energy, the regularity and frequency of meals, and the importance of these factors for metabolic health. A growing body of animal and human evidence indicates that the timing of food intake throughout the day can have a significant and beneficial impact on the metabolic health and well-being of individuals. In particular, both the timing and frequency of meals have been associated with obesity, type 2 diabetes mellitus (T2DM), cardiovascular disease, and other chronic conditions. Today's busy lifestyle makes many people skip breakfast and eat late at night. Eating late at night has been shown to cause a circadian misalignment, with the latter having a negative impact on weight control and glucose metabolism. Additionally, some studies have found a relatively strong association between skipping breakfast and insulin resistance, and T2DM. Against the backdrop of escalating obesity and T2DM rates, coupled with the recognized influence of food timing on disease evolution and control, this review aimed to synthesize insights from epidemiological and intervention studies of the interplay of timing of food intake and macronutrient consumption, reporting their impact on obesity and T2DM.

Temporal patterns of energy intake identified by the latent class analysis in relation to prevalence of overweight and obesity in Iranian adults

We aimed to identify temporal patterns of energy intake and investigate their association with adiposity. We performed a cross-sectional study of 775 adults in Iran. Information about eating occasions across the day was collected by three 24-h dietary recalls. Latent class analysis (LCA) was used to identify temporal eating patterns based on whether or not an eating occasion occurred within each hour of the day. We applied binary logistic regression to estimate the OR and 95 % CI of overweight and obesity (defined as BMI of 25-29·9 and ≥ 30 kg/m2, respectively) across temporal eating patterns while controlling for potential confounders. LCA grouped participants into three exclusive sub-groups named 'Conventional', 'Earlier breakfast' and 'Later lunch'. The 'Conventional' class was characterised by high probability of eating occasions at conventional meal times. 'Earlier breakfast' class was characterised by high probability of a breakfast eating occasion 1 h before the conventional pattern and a dinner eating occasion 1 h after the conventional pattern, and the 'Later lunch' class was characterised by a high probability of a lunch eating occasion 1 h after the conventional pattern. Participants in the 'Earlier breakfast' pattern had a lower likelihood of obesity (adjusted OR: 0·56, 95 % CI: 0·35, 0·95) as compared with the 'Conventional' pattern. There was no difference in the prevalence of obesity or overweight between participants in the 'Later lunch' and the 'Conventional' patterns. We found an inverse association between earlier eating pattern and the likelihood of obesity, but reverse causation may be a plausible explanation.

Chrononutrition and metabolic health in children and adolescents: a systematic review and meta-analysis

CONTEXT

Obesity has emerged as a global health issue for the pediatric population, increasing the need to investigate physiopathological aspects to prevent the appearance of its cardiometabolic complications. Chrononutrition is a field of research in nutritional sciences that investigates the health impact of 3 different dimensions of feeding behavior: regularity of meals, frequency, and timing of food intake.

OBJECTIVE

We carried out a systematic review and meta-analysis to investigate the association between chrononutrition in children and adolescents and the risk of overweight/obesity or a cluster of metabolic abnormalities related to glucose and lipid metabolism, blood pressure, and cardiovascular disease risk.

DATA EXTRACTION

A literature search was performed using PubMed, EMBASE, and The Cochrane Library for relevant articles published before August 2022.

DATA ANALYSIS

A total of 64 articles were included in the narrative synthesis (47 cross-sectional and 17 cohort studies), while 16 studies were included in the meta-analysis. Meta-analysis showed that non-daily breakfast consumers (≤6 d/wk) had a higher risk of overweight/obesity (odds ratio [OR], 1.45; 95% confidence interval [CI], 1.08-1.82] compared with daily breakfast eaters (7 d/wk). Similarly, irregular breakfast consumption (only 0-to-3 times/wk) increased the risk of abdominal obesity (waist-to-height ratio ≥ 0.5) compared with regular consumption (5-to-7 times/wk) (OR, 1.38; 95% CI, 1.26-1.49). There was evidence to suggest that a regular frequency of meal consumption (≥4 times/d) is preventive against overweight/obesity development compared with fewer meals (≤3 times/d) (OR, 0.83; 95% CI, 0.70-0.97). In the narrative synthesis, snacking habits showed controversial results, while food timing was the most understudied dimension.

CONCLUSION

Overall, our data indicate a potential implication of chrononutrition in affecting pediatric metabolic health; however, the evidence of this association is limited and heterogeneous. Further prospective and intervention studies with a consistent approach to categorize the exposure are needed to elucidate the importance of chrononutrition for pediatric metabolic health.

Chrononutrition behaviors, sugar-sweetened beverage consumption, sleep quality and the association with body mass index among Malaysian women

The present study aimed to determine the association between chrononutrition behaviors, sugar-sweetened beverage intake, and sleep quality among Malaysian women. A cross-sectional study using a validated, self-administered Chrononutrition Profile Questionnaire, Beverage Questionnaire and Sleep Quality Index were conducted among 934 Malaysian women. Multinomial logistic regression was performed to obtain odds ratios of being overweight/underweight and to test the association with poor sleep quality. 40% of Malaysian women were either overweight or obese and 65.4% had poor sleep quality. We found that breakfast skipping (OR: 4.101; CI: 2.378-7.070), poor evening eating (OR: 4.073; CI: 1.631-10.186), and eating the largest meal at night (OR: 6.970; CI: 1.944-24.994) increased the odds of being underweight. On the other hand, the daily consumption of 100% fruit juices (OR: 1.668; CI: 1.058-1.731), daily consumption of sweetened coffee or tea (OR: 1.707; CI: 1.162-2.508) and consumption of diet soft drinks by 6 times or fewer (OR: 1.484; CI: 1.066-2.064) are associated with increased odds of being overweight. However, when adjusted, only poor evening latency (AOR: 16.638; CI: 1.986-139.383) revealed an increased odd of being underweight. The highest odds predicting poor sleep quality were found for eating the largest meal during dinner (OR: 3.696; CI: 1.967-6.945) and (AOR: 2.194; CI: 1.119-4.304) when adjusted. Hence, the result indicates that multifactorial impacts on women's body weight and recommendations to adjust chrononutrition and sugar-sweetened beverages intake in lifestyle must be done carefully considering other parameters together.

Sweet treats before sleep disrupt the clock system and increase metabolic risk markers in healthy rats

AIM

Biological rhythms are endogenously generated natural cycles that act as pacemakers of different physiological mechanisms and homeostasis in the organism, and whose disruption increases metabolic risk. The circadian rhythm is not only reset by light but it is also regulated by behavioral cues such as timing of food intake. This study investigates whether the chronic consumption of a sweet treat before sleeping can disrupt diurnal rhythmicity and metabolism in healthy rats.

METHODS

For this, 32 Fischer rats were administered daily a low dose of sugar (160 mg/kg, equivalent to 2.5 g in humans) as a sweet treat at 8:00 a.m. or 8:00 p.m. (ZT0 and ZT12, respectively) for 4 weeks. To elucidate diurnal rhythmicity of clock gene expression and metabolic parameters, animals were sacrificed at different times, including 1, 7, 13, and 19 h after the last sugar dose (ZT1, ZT7, ZT13, and ZT19).

RESULTS

Increased body weight gain and higher cardiometabolic risk were observed when sweet treat was administered at the beginning of the resting period. Moreover, central clock and food intake signaling genes varied depending on snack time. Specifically, the hypothalamic expression of Nampt, Bmal1, Rev-erbα, and Cart showed prominent changes in their diurnal expression pattern, highlighting that sweet treat before bedtime disrupts hypothalamic control of energy homeostasis.

CONCLUSIONS

These results show that central clock genes and metabolic effects following a low dose of sugar are strongly time-dependent, causing higher circadian metabolic disruption when it is consumed at the beginning of the resting period, that is, with the late-night snack.

Association between dietary carbohydrate intake and risk of type 2 diabetes: a systematic review and meta-analysis of cohort studies

Background

Previous meta-analyses have assessed the relationship between carbohydrate intake and type 2 diabetes (T2D) risk; however, they included few studies of Asian populations who have a higher carbohydrate intake and lower insulin secretory capacity than non-Asians. Since the publication of the previous meta-analyses, three further studies of Asian populations have been conducted. Based on this background, the present study aimed to perform an updated systematically examine observational studies concerning the link between dietary carbohydrate intake and T2D risk.

Methods

We conducted a systematic search for cohort studies that investigated the target association. For each analyzed study, parameter-adjusted risk ratios were used to compare the lowest and highest carbohydrate-intake groups in terms of their risk of incident T2D. The risk ratios were calculated using a random-effects model.

Results

Ten publications were analyzed. Overall, carbohydrate intake was found not to be associated with increased risk ratios of incident T2D (risk ratio [RR] = 1.07; 95% confidence interval [95% CI] = 0.94, 1.21; P < 0.01, I2 = 61.9%). However, studies of Asian populations reported that high carbohydrate intake is significantly associated with this risk (RR = 1.29; 95% CI 1.15, 1.45; P = 0.59, I2 = 0.0%).

Conclusions

This updated meta-analysis showed that, overall, carbohydrate intake is not associated with the risk of T2D; nevertheless, a significant association exists among Asian populations. To confirm the association between dietary carbohydrate intake and T2D risk observed in this study, further evidence from long-term observational studies of Asian populations is required.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-023-00642-0.

Higher energy consumption in the evening is associated with increased odds of obesity and metabolic syndrome: findings from the 2016-2018 Korea National Health and Nutrition Examination Survey (7th KNHANES)

OBJECTIVES

Chrono-nutrition emphasizes meal timing in preventing obesity and metabolic disorders. This study explores the impact of temporal dietary patterns (TDPs) on obesity and metabolic syndrome (MetS) in Korean adults aged 20 years to 65 years.

METHODS

We utilized dynamic time warping method and Kernel k-means clustering to investigate diet quality and the odds ratios (ORs) of obesity and MetS with different TDPs using data from the 7th Korea National Health and Nutrition Examination Survey.

RESULTS

Participants were divided into three groups based on relative energy intake over 24 hours. After adjusting for age and gender, Cluster 3 (with the highest proportion of energy intake in the evening) had the lowest Healthy Eating Index scores compared to other clusters. Following adjustment for key covariates, Cluster 3 showed the highest values for body mass index, waist circumference, blood pressure, total cholesterol, and triglycerides. Compared to Cluster 1 (with a lower proportion of energy intake in the evening), Cluster 2 and Cluster 3 had ORs for obesity of 1.12 (95% confidence interval [CI], 0.97 to 1.30) and 1.19 (95% CI, 1.03 to 1.37), respectively. For MetS, the ORs were 1.26 (95% CI, 1.08 to 1.48) and 1.37 (95% CI, 1.17 to 1.61) when comparing Cluster 2 and Cluster 3 to Cluster 1.

CONCLUSIONS

This study reveals that individuals with higher energy intake in the evening have increased odds of obesity and MetS, even after adjusting for major covariates, including age and total energy intake.

The effect of breakfast on childhood obesity: a systematic review and meta-analysis

Objective

Previous cohort trials have shown that skipping breakfast increases the risk of obesity or overweight in children. However, this finding remains controversial. Through a meta-analysis, this study systematically evaluated the effect of skipping breakfast on the prevalence of obesity or overweight in children.

Methods

We performed a literature search for studies published until March 19, 2023. using the Cochrane, PubMed, and Embase databases. Based on the inclusion and exclusion criteria, observational studies on the relationship between skipping breakfast and overweight/obesity in children and adolescents were analyzed. Three investigators independently screened the relevant literature, extracted the data, and assessed the risk of bias. The quality of the included studies was assessed using the Newcastle-Ottawa Scale (NOS). A random-effects model was used. The odds ratio (OR) with its 95% confidence interval (CI) was used to indicate the effect size.

Results

A total of 40 retrospective studies with 323,244 children ranging in age from 2 to 20 years were included in this study. The results of this meta-analysis showed that children and adolescents who skipped breakfast had a significantly higher prevalence of obesity or overweight than those who ate breakfast (OR, 1.59; 95% CI, 1.33-1.90; P < 0.001). Skipping breakfast was positively associated with overweight in children and adolescents (OR, 1.37; 95% CI, 1.23-1.54; P < 0.001). Similarly, skipping breakfast was positively associated with obesity in children and adolescents (OR, 1.51; 95% CI, 1.30-1.76; P < 0.001). The effect was also different by sex, with girls being the most affected (OR, 1.47; 95% CI, 1.23-1.76; P < 0.001). There was also a correlation between skipping breakfast and abdominal obesity in children (OR, 0.65; 95% CI, 0.55-0.77; P < 0.001).

Conclusion

This meta-analysis suggested that skipping breakfast is associated with an increased risk of overweight/obesity in children and adolescents. The findings provide support for a possible protective role of breakfast against excessive weight gain in children and adolescents. However, more rigorous study designs with validated and standardized measures of relevant variables are needed.

Relationship between eating habits, sleep patterns and physical activity and the degree of obesity in children and adolescents

INTRODUCTION

Childhood obesity is an extremely prevalent pathology and, in order to be able to address it, it is necessary to understand the factors that influence on its genesis and maintenance. We hypothesise that the timing of meals and sleep, the regularity of these throughout the week and a sedentary lifestyle influence the degree of obesity.

MATERIAL AND METHODS

We included children and adolescents with obesity who attended a first check-up visit at the Childhood Obesity Unit between January 2018 and February 2020. The data were obtained from a questionnaire on food (36-h intake, frequency of consumption, eating times and habits) and sleep.

RESULTS

The degree of obesity was influenced to a greater extent by later meal times and the distribution of calories throughout the day (less at breakfast, more at dinner) than by the total number of calories ingested. In addition, a lower consumption of vegetables was related to a higher degree of obesity. The difference between the hours of sleep at weekends and on weekdays correlated positively with a higher degree of obesity. Finally, the anthropometric data correlated negatively with the number of hours of physical activity. Almost half of the children did not exercise after school.

CONCLUSION

In the approach to childhood obesity, it is necessary to include recommendations on the regularity of meal and sleep times, as well as the distribution of calories throughout the day. Additionally, it is necessary to encourage the practice of physical exercise.

Association of meal timing of energy, macronutrients and foods with hypercholesterolaemia in the US adults

Few studies examined the association of energy, macronutrients and food consumption at dinner v. breakfast with hypercholesterolaemia. A total of 27 911 participants from the National Health and Nutrition Examination Survey (2003-2016) were included in the cross-sectional study. Energy, macronutrients and food consumption at breakfast, dinner and the difference at dinner v. breakfast (Δratio) were calculated. Multiple logistic regression models and substitution effects of foods at dinner with breakfast were also performed. After adjustment for potential covariates, compared with the lowest quintile, participants in the highest quintile of Δratio in terms of energy had a higher risk of prevalent hypercholesterolaemia (ORΔratio of energy 1·16, 95 % CI (1·01, 1·33)) mainly due to Δratio of low-quality carbohydrates and plant protein (ORΔratio of low-quality carbohydrates 1·19; 95 % CI (1·05, 1·35)); ORΔratio of plant protein 1·13; 95 % CI (1·01, 1·28)). ΔAdded sugars and Δnuts were associated with hypercholesterolaemia (ORΔadded sugars 1·01; 95 % CI (1·00, 1·02)); ORΔnuts 1·08; 95 % CI (1·01, 1·16)). Furthermore, the substitution of added sugars, nuts and processed meat at dinner with breakfast could reduce the OR of hypercholesterolaemia. This study indicated that among US adults, overconsumption of energy, macronutrients including low-quality carbohydrates and plant protein at dinner than breakfast was significantly associated with a higher risk of prevalent hypercholesterolaemia. The replacing of added sugar, nuts and processed meat at dinner with breakfast reduced the risk of prevalent hypercholesterolaemia. This study emphasised the importance of meal timing in the prevention of hypercholesterolaemia.

The Longitudinal Interplay between Sleep, Anthropometric Indices, Eating Behaviors, and Nutritional Aspects: A Systematic Review and Meta-Analysis

Sleep is fundamental for adolescents' healthy development but undergoes dramatic changes in quantity and quality due to the conflict between biological and social rhythms. Insufficient sleep has been associated with worse physical health status and irregular eating behaviors in adolescents. This review aims to systematically synthesize the longitudinal associations between adolescents' sleep dimensions (i.e., duration, timing, quality, and insomnia symptoms) and physical health indicators (i.e., anthropometric indices, fat percentage, and risk of obesity), eating behaviors, and nutritional aspects (i.e., type of diet related to the intake of specific foods and nutrients, amount and timing of food consumption, energy expenditure). A total of 28 longitudinal studies were included. The meta-analytic results showed that longer sleep duration, better sleep quality, and lower insomnia symptoms were associated with lower BMI and fat percentage and that shorter sleep duration (<7 h) and lower sleep quality were associated with a higher risk of obesity. Conversely, anthropometric indices were not related to sleep over time. Limited literature examined the bidirectional association between adolescents' sleep and their eating behaviors and nutritional aspects. Such knowledge sheds new light on the role of sleep for adolescents' health, highlighting the need to examine further the interplay between these variables.

Introduction to the dietary management of obesity in adults

Obesity is a multifaceted and complex condition that requires holistic management. It currently affects nearly one in four adults in the UK, with the UK ranked 10th globally for the highest obesity rates. Obesity is projected to have an economic burden of ∼£2 billion per year by 2030 in the UK.1 Excess weight gain can coincide with myriad health concerns and multiple health conditions, which can be physical, metabolic or psychosocial. This includes type 2 diabetes mellitus (T2DM), hypertension, coronary heart disease, osteoarthritis, obstructive sleep apnoea, reproductive disorders, depression and cancer2; hence, there has been a significant emphasis on obesity prevention. Obesity is often associated with weight stigma, impacting psychological wellbeing and quality of life. This can influence an individual's likelihood of seeking support, delaying appropriate input from healthcare professionals, with a knock-on effect on pre-existing health conditions. This review explores the management of obesity from a nutritional perspective, because modifying dietary intake is essential to reduce the risk of non-communicable diseases, including those associated with obesity.

Stressful Life Events, Unhealthy Eating Behaviors and Obesity among Chinese Government Employees: A Follow-Up Study

Background: The underlying mechanisms of the relationship between stressful life events and obesity among Chinese workers are unclear. Objective: This study aimed to understand the processes and mechanisms involved in stressful life events, unhealthy eating behavior, and obesity among Chinese workers. Methods: From January 2018 to December 2019, a total of 15,921 government employees were included at baseline and they were followed-up until May 2021. Stressful life events were assessed using the Life Events Scale, and unhealthy eating behavior was assessed using four items. BMI was calculated as weight (kg) divided by height (m²) using physically measured data. Results: Overeating at each mealtime (OR = 2.21, 95%CI: 1.78-2.71) at baseline led to reports of higher risk of obesity at follow up. Eating before going to bed at night sometimes (OR = 1.51, 95%CI: 1.31-1.73) or often (OR = 3.04, 95%CI: 2.28-4.05) at baseline led to reports of higher risk of obesity at follow-up. Eating out sometimes (OR = 1.74, 95%CI: 1.47-2.07) or often (OR = 1.59, 95%CI: 1.07-2.36) at baseline led to reports of higher risk of obesity at follow-up. Stressful life events were not directly associated with obesity, but unhealthy eating behaviors, including overeating at each mealtime (β = 0.010, 95%CI: 0.007-0.014; β = 0.002, 95%CI: 0.001-0.004, respectively) and irregular meal timing (β = -0.011, 95%CI: -0.015--0.008; β = -0.004, 95%CI: -0.006--0.001, respectively), significantly mediated the associations between stressful life events at baseline and obesity at both baseline and follow-up. Conclusions: Unhealthy eating behaviors mediated the relationship between stressful life events and obesity. Interventions should be provided to workers who have experienced stressful life events and unhealthy eating behaviors.

Circadian PER1 controls daily fat absorption with the regulation of PER1-PKA on phosphorylation of bile acid synthetase

Several epidemiological studies suggest a correlation between eating time and obesity. Night eating syndrome characterized by a time-delayed eating pattern is positively associated with obesity in humans as well as in experimental animals. Here, we show that oil intake at night significantly makes more fat than that at day in wild-type mice, and circadian Period 1 (Per1) contributes to this day-night difference. Per1-knockout mice are protected from high-fat diet-induced obesity, which is accompanied by a reduction in the size of the bile acid pool, and the oral administration of bile acids restores fat absorption and accumulation. We identify that PER1 directly binds to the major hepatic enzymes involved in bile acid synthesis such as cholesterol 7alpha-hydroxylase and sterol 12alpha-hydroxylase. A biosynthesis rhythm of bile acids is accompanied by the activity and instability of bile acid synthases with PER1/PKA-mediated phosphorylation pathways. Both fasting and high fat stress enhance Per1 expression, increasing the fat absorption and accumulation. Our findings reveal that Per1 is an energy regulator and controls daily fat absorption and accumulation. Circadian Per1 controls daily fat absorption and accumulation, suggesting Per1 is a potential candidate of a key regulator in stress response and the relevant obesity risk.

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.

Associations of timing of food intake with energy intake, eating behaviour traits and psychosocial factors in adults with overweight and obesity

Introduction

Whether a late distribution of food intake impacts obesity through increased energy intake remains uncertain and the behavioural characterization of late eating needs to be further investigated. The first objective of this study was to assess the associations between late eating and body mass index (BMI) and total energy intake (TEI), and whether TEI mediates the association between late eating and BMI. The second objective was to assess the associations between late eating and eating behaviour traits or psychosocial factors and whether eating behaviour traits mediate the association between late eating and TEI.

Methods

Baseline data from 301 individuals (56% women, age = 38.7 ± 8.5 years; BMI = 33.2 ± 3.4 kg/m²), who participated in four weight loss studies were used in this cross-sectional study. Total energy intake was assessed using a three-day food record from which the percentage of TEI after 17:00 and after 20:00 was calculated. Eating behaviour traits and psychosocial factors were assessed with questionnaires. Pearson correlations and mediation analyses adjusted for age, sex, underreporting of energy intake, sleep duration and bedtime were performed.

Results

Percent TEI after 17:00 and after 20:00 were associated with TEI (r = 0.13, p = 0.03 for both), and TEI mediated the association between percent TEI after 17:00 and BMI (β = 0.01 ± 0.01, 95% CI: 0.001, 0.02). Percent TEI after 17:00 was associated with disinhibition (r = 0.13, p = 0.03) and percent TEI after 20:00 was associated with susceptibility to hunger (r = 0.13, p = 0.03), stress (r = 0.24, p = 0.002) and anxiety (r = 0.28, p = 0.0004). In women, disinhibition mediated the association between percent TEI after 17:00 and TEI (β = 3.41 ± 1.43, 95% CI: 0.92, 6.47). Susceptibility to hunger mediated the association between percent TEI after 20:00 and TEI (β = 0.96 ± 0.59, 95% CI: 0.02, 2.34) in men and women.

Conclusion

Late eating is associated with TEI and suboptimal eating behaviours which could contribute to explaining the association between timing of food intake and obesity.

Relationship between the Biological Clock and Inflammatory Bowel Disease

The biological clock is a molecular oscillator that generates a 24-hour rhythm in accordance with the earth's rotation. Physiological functions and pathophysiological processes such as inflammatory bowel diseases (IBD) are closely linked to the molecular clock. This review summarizes 14 studies in humans and mice on the interactions between the biological clock and IBD. It provides evidence that IBD negatively affect core clock gene expression, metabolism and immune functions. On the other hand, disruption of the clock promotes inflammation. Overexpression of clock genes can lead to inhibition of inflammatory processes, while silencing of clock genes can lead to irreversible disease activity. In both human and mouse studies, IBD and circadian rhythms have been shown to influence each other. Further research is needed to understand the exact mechanisms and to develop potential rhythm-related therapies to improve IBD.

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.

Snacking behavior is associated with snack quality, overall diet quality, and body weight among US college students

Snacking behavior may affect snack quality, overall diet quality, and body weight; however, the associations between these variables have not been studied among college students. The objective of this study was to associate snacking behaviors with snack quality, diet quality, and weight status among college students with overweight and obesity. We hypothesized that a higher snacking frequency, accessibility and availability of unhealthy snacks, and lack of knowledge would be associated with lower snack and diet quality, and higher weight. Participants (n = 140) completed a snack behavior questionnaire, three 24-hour dietary recalls to assess diet quality using Healthy Eating Index 2015 (HEI-2015), and snack score using an algorithm based on the US DA Smart Snack guidelines and reported weight and height to calculate body mass index (BMI). Analysis of variance and Pearson correlation was used in the analyses. After adjusting for confounders, snack frequency was not associated with snack score, HEI-2015 score, or BMI, but evening snacks had a significantly lower snack score compared with late afternoon snacks (P = .017). Also, those with more accessibility and availability of unhealthy snacks had a lower snack score (P = .001), lower HEI-2015 score (P = .006), and higher BMI (P = .019). Snacking for pleasure was significantly associated with a lower snack score (P = .037). Snack score was positively correlated with HEI-2015 score but not with BMI. In conclusion, late snacking, unhealthy snack environment, and snacking for pleasure were associated with lower snack and diet quality. These findings could be used in future intervention strategies to improve snacking behaviors and the food environment.

A hypothetical intervention of the timing of dietary intake on weight and body composition after initial weight loss

OBJECTIVE

This study estimated the effect of hypothetical interventions of higher and lower frequency of breakfast and post-dinner snack consumption (breakfast consumption 0-4 vs. 5-7 times/week and post-dinner snack consumption 0-2 vs. 3-7 times/week) on changes in body weight and composition over 18 months after a successful 6-month standard behavioral weight-loss program.

METHODS

The study analyzed data from the Innovative Approaches to Diet, Exercise and Activity (IDEA) study.

RESULTS

If all participants consumed a breakfast meal 5 to 7 times/week over 18 months, they would have regained 2.95 kg of body weight on average (95% CI: 2.01 to 3.96), which is 0.59 kg (95% CI: -0.86 to -0.32) lower than if all participants consumed breakfast 0 to 4 times/week. If all participants consumed a post-dinner snack 0 to 2 times/week, they would have regained 2.86 kg of body weight on average (95% CI: 0.99 to 5.25), which is 0.83 kg (95% CI: -1.06 to -0.59) lower than if all consumed a post-dinner snack 3 to 7 times/week.

CONCLUSIONS

Regular breakfast consumption and minimizing post-dinner snacking may modestly mitigate weight and body fat regain over 18 months after initial weight loss.

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.

Effect of feeding regimen on circadian activity rhythms of food anticipatory by ghrelin hormone in a pig model

Increasingly diverse meal patterns affect the internal body clock. Ghrelin secretion is closely associated with the anticipation of a regularly scheduled mealtime, leading ghrelin to be a putative candidate for food-related entraining signals that drive activity rhythms. Here, growing pigs with different meal frequencies were used to construct an irregular eating pattern model. We found that irregular eating patterns changed central ghrelin levels of pigs, affected the circadian entrainment and circadian rhythm pathways in hypothalamus tissue, and altered the daily behavior and food anticipatory activity (FAA). To determine whether ghrelin exerts an effect, growing pigs were intravenously injected with ghrelin antagonist [D-Lys3]-GHRP-6 for 7 days. We showed here that [D-Lys3]-GHRP-6 administration decreased locomotor activity of growing pigs in the 4-h window preceding onset of food availability. In addition, we also confirmed that the direct role of ghrelin in molecular mechanism of regulating clock genes expression via calcium mobilization through intracellular PKC/PLC and AC/PKA pathways in vitro. Collectively, irregular eating patterns affect the central circadian system by ghrelin, supporting ghrelin as a temporal messenger of food-entrainment in hypothalamic circadian functions.

Association between Late-Eating Pattern and Higher Consumption of Ultra-Processed Food among Italian Adults: Findings from the INHES Study

Late eating is reportedly associated with adverse metabolic health, possibly through poor diet quality. We tested the hypothesis that meal timing could also be linked to food processing, an independent predictor of health outcomes. We analysed data on 8688 Italians (aged > 19years) from the Italian Nutrition & HEalth Survey (INHES) established in 2010-2013 throughout Italy. Dietary data were collected through a single 24 h dietary recall, and the NOVA classification was used to categorize foods according to increasing levels of processing: (1) minimally processed foods (e.g., fruits); (2) culinary ingredients (e.g., butter); (3) processed foods (e.g., canned fish); (4) ultra-processed foods (UPFs; e.g., carbonated drinks, processed meat). We then calculated the proportion (%) of each NOVA group on the total weight of food eaten (g/d) by creating a weight ratio. Subjects were classified as early or late eaters based on the population's median timing for breakfast, lunch and dinner. In multivariable-adjusted regression models, late eaters reported a lower intake of minimally processed food (β = -1.23; 95% CI -1.75 to -0.71), a higher intake of UPF (β = 0.93; 0.60 to 1.25) and reduced adherence to a Mediterranean Diet (β = -0.07; -0.12 to -0.03) as compared to early eaters. Future studies are warranted to examine whether increased UPF consumption may underpin the associations of late eating with adverse metabolic health reported in prior cohorts.

Unhealthy lifestyle associated with increased risk of macro- and micro-vascular comorbidities in patients with long-duration type 2 diabetes: results from the Taiwan Diabetes Registry

BACKGROUND

Unhealthy lifestyle has been associated with obesity and type 2 diabetes. Whereas its association with vascular complications in patients with long-duration of type 2 diabetes is still uncertain.

METHODS

A total of 1188 patients with long-duration of type 2 diabetes from the Taiwan Diabetes Registry (TDR) data were analyzed. We stratified the severity of unhealthy lifestyle via scoring three factors (sleep duration <7 or >9 h, sit duration ≥ 8h, and meal numbers ≥ with night snack) and analyzed their associations with the development of vascular complications using logistic regression analysis. Besides, we also included 3285 patients with newly diagnosed type 2 diabetes as the comparison.

RESULTS

Increased numbers of factors that stand for unhealthy lifestyle were significantly associated with the development of cardiovascular disease, peripheral arterial occlusion disease (PAOD) and nephropathy in patients with long-duration of type 2 diabetes. After adjusting multiple covariables, having ≥ 2 factors of unhealthy lifestyle remained significant associations with cardiovascular disease and PAOD, with an odds ratio (OR) of 2.09 (95% confidence interval [CI] 1.18-3.69) and 2.68 (95% CI 1.21-5.90), respectively. Among individual factor for unhealthy lifestyle behaviors, we revealed that eating ≥ 4 meals per day with night snack increased the risk of cardiovascular disease and nephropathy after multivariable adjustment (OR of 2.60, 95% CI 1.28-5.30; OR of 2.54, 95% CI 1.52-4.26, respectively). Whereas sit duration for ≥ 8 h per day increased the risk of PAOD (OR of 4.32, 95% CI 2.38-7.84).

CONCLUSION

Unhealthy lifestyle is associated with increased prevalence of macro- and micro-vascular comorbidities in Taiwanese patients with long-duration type 2 diabetes.

Associations between Timing and Duration of Eating and Glucose Metabolism: A Nationally Representative Study in the U.S

Diabetes is highly prevalent and is associated with dietary behaviors. Time-restricted eating, which consolidates caloric intake to a shortened eating duration, has demonstrated improvement in metabolic health. Timing of eating could also impact metabolism. Our objective was to examine whether the timing of eating was associated with metabolic health independently of eating duration. Data (n = 7619) are from four cycles (2005-2012) of the National Health and Nutrition Examination Survey (NHANES), a nationally representative U.S. survey that included surveys, physical examinations, and dietary recalls. The primary exposures are eating duration and eating start time estimated from two non-consecutive dietary recalls. Primary outcomes were fasting glucose and estimated insulin resistance using the homeostatic model assessment method (HOMA-IR). The mean (95% CI) eating duration was 12.0 h (11.9-12.0) and the mean (95% CI) start time was 8:21 (8:15-8:26). Earlier eating start time was significantly associated with lower fasting glucose and estimated insulin resistance but eating interval duration was not. Every hour later that eating commenced was associated with approximately 0.6% higher glucose level and 3% higher HOMA-IR (both p < 0.001). In this cross-sectional study, earlier eating start time was associated with more favorable metabolic measures, indicating that meal timing is another important characteristic of dietary patterns that may influence metabolism.

Daily Energy Intake Distribution and Cognitive Performance in Non-Demented Individuals

Cognitive disorders have become important public health issues around the world. Studies evaluating the association between cognitive decline and food timing are lacking. The objective of this study was to examine the potential association between energy intake distribution during the day and cognitive performance in cognitively healthy and mildly cognitive impaired individuals. Data were derived from the ongoing Albion study which includes people aged 40 years or older who have a positive family history of cognitive disorder or concern about their cognitive status. A thorough dietary and cognitive assessment was performed. Participants consuming low energy intake at the beginning of the day or high energy at the end of the day had higher cognitive function compared to participants characterized by the opposite pattern. This trend remained statistically significant even after adjustment for potential confounders (p = 0.043). This study suggests that individuals with worse cognitive function may choose to eat earlier during the day, when cognitive performance is better, and it might be hypothesized that a meal pattern characterized by high energy consumption at the beginning of the day or low energy at the end of the day could be a marker of cognitive impairment.

The impact of experimentally shortened sleep on timing of eating occasions in adolescents: A brief report

Short sleep increases the risk for obesity in adolescents. One potential mechanism relates to when eating occurs in the day. This study investigated the impact of shortened sleep on eating occasion timing in adolescents. Ninety-three healthy 14- to 17-year-olds (62% female) completed a within-subject experimental sleep manipulation, engaging in 5-night spans of Short Sleep (6.5-hr sleep opportunity) or Healthy Sleep (9.5-hr sleep opportunity), with order randomized. During each condition, adolescents completed three 24-hr diet recall interviews. Repeated-measure t-tests assessed the sleep manipulation effect on each adolescent's number of meals, first and last eating occasion (relative to the clock and time since sleep onset/offset), feeding window (timespan from first to last eating), and the midpoint of feeding. The timing of the first eating occasion was similar across conditions, relative to the clock (Short = 08:51, Healthy = 08:52) and to time since waking (Short = 2.0 hr, Healthy = 2.2 hr). The timing of the last eating occasion was later relative to the clock (Short = 20:34, Healthy = 19:39; p < 0.001), resulting in a longer feeding window (Short = 11.7 hr, Healthy = 10.8 hr, p < 0.001) and a later midpoint in the feeding window (Short = 14:41, Healthy = 14:18, p = 0.002). The gap between last eating occasion and sleep onset was larger in Short (4.2 hr) than Healthy Sleep (2.9 hr; p < 0.001), though the last eating occasion was much earlier than when they fell asleep during either condition. Shortened sleep resulted in adolescents eating later and lengthening the daily feeding window. These findings may help explain the link between shortened sleep and increased obesity risk in adolescents.

Infusion timing and sleep habits of adults receiving home parenteral and enteral nutrition: A patient-oriented survey study

BACKGROUND

The emerging field of chrononutrition investigates the effects of the timing of nutritional intake on human physiology and disease pathology. It remains largely unknown when patients receiving home nutrition support routinely administer home parenteral nutrition (HPN) and/or home enteral nutrition (HEN).

METHODS

The present descriptive study included data collected from a patient-oriented survey designed to assess the timing of infusions and sleep habits of patients receiving HPN and HEN in the United States.

RESULTS

A total of 100 patients were included. Patients had a mean age of 44.1 years and 81% were female. Among 73 patients supported with HPN and 27 patients supported with HEN, 86% and 44% reported overnight infusions, respectively. The median start and end times of overnight infusions were 2100 (interquartile range [IQR] = 1900-2200) and 0800 (IQR = 0700-1000), respectively, for HPN and 2000 (IQR = 1845-2137) and 0845 (IQR = 0723-1000), respectively, for HEN. Overnight infusions started 2.0 h (IQR = 1.1-3.0) and 2.0 h (IQR = 0.6-3.3) before bedtime for HPN and HEN, respectively, and stopped 12.9 min (IQR = -21.3 to 29.1) and 30.0 min (IQR = -17.1 to 79.3) after wake time for HPN and HEN, respectively. Sleep disruption because of nutrition support or urination was most common among patients receiving infusions overnight compared with those receiving infusions continuously or during the daytime.

CONCLUSIONS

Our survey study focusing on a novel and medically relevant dimension of nutrition found that most HPN-dependent and HEN-dependent patients receive infusions overnight while asleep. Our findings suggest that overnight infusions coinciding with sleep may result in sleep and circadian disruption.

The association of energy and macronutrient intake at breakfast and cardiovascular disease in Chinese adults: From a 14-year follow-up cohort study

Background

We aimed to examine the associations between energy and macronutrient intakes at breakfast and the incidence of cardiovascular events among Chinese adults.

Methods

There were 12,937 participants from the China Health and Nutrition Survey who met the study criteria and completed six rounds of questionnaires in 1997, 2000, 2004, 2006, 2009, and 2011. Combined weighing methods with 24-h dietary recall were used to measure dietary intake throughout the day. Intakes of macronutrients at breakfast were calculated using energy provided by nutrients as a percentage of breakfast energy. We calculated hazard ratios using a multivariable Cox frailty model with random intercepts to account for household clustering.

Results

During follow-up, we documented 453 (3.6 per 1,000 person-years) major cardiovascular events, 195 (1.5 per 1,000 person-years) myocardial infarctions, and 293 (2.3 per 1,000 person-years) strokes. In Chinese adults, more breakfast carbohydrates or less proteins intake was associated with the reduced risk of cardiovascular diseases. Especially for women, higher intake of breakfast carbohydrates was associated with a lower risk of major cardiovascular events (quintile 5 vs. quintile 1, HR 0.47 [95%CI 0.30-0.74]; p _trend = 0.0008) and stroke (quintile 5 vs. quintile 1, HR 0.48 [95%CI 0.26-0.88]; p _trend = 0.0006). Higher intake of breakfast proteins was associated with a higher risk of major cardiovascular events (quintile 5 vs. quintile 1, HR 1.77 [95%CI 1.12-2.79]; p _trend = 0.1162), myocardial infarction (quintile 5 vs. quintile 1, HR 2.49 [95%CI 1.21-5.11]; p _trend = 0.2641). There was a significant association between breakfast fat intake and cardiovascular diseases in the adult population, but less significant correlation was found in Chinese men or women. Breakfast fat intake was positively associated with the risk of major cardiovascular events (quintile 5 vs. quintile 1, HR 1.74 [95%CI 1.27-2.36]; p _trend = 0.0070), myocardial infarction (quintile 5 vs. quintile 1, HR 2.03 [95%CI 1.23-3.37]; p _trend = 0.0168), and stroke (quintile 5 vs. quintile 1, HR 1.64 [95%CI 1.12-2.41]; p _trend = 0.0732). There was a significant reduction in major cardiovascular events and stroke when breakfast energy intake was moderated, even if the independence of skipping breakfast.

Conclusion

High carbohydrate intake and low protein and fat intake at breakfast may contribute to cardiovascular health while maintaining a moderate energy intake.

Sex differences and indications of metabolic compensation in within-day energy balance in elite Division 1 swimmers

To determine whether mismatched energy intake and expenditure across the day and associated sex differences may be related with metabolic compensation and/or negative health outcomes, we assessed total-day and hourly energy balance (TDEB and EB), total-day and hourly energy intake (TDEI and EI), total-day and hourly energy expenditure (TDEE and EE) and within-day energy balance (WDEB) in elite male and female swimmers (n = 25; 18-22 years). Total triiodothyronine (TT₃), resting metabolic rate (RMR), and the ratio of actual-to-predicted RMR were determined. Males exhibited higher TDEB (+758 ± 702 kcal vs +52 ± 505 kcal, t-test; p = 0.007) than females. Males exhibited a more positive hourly EB, driven by greater hourly EI at 11:00, 13:00, 16:00, and 19:00 h (ANOVA, p < 0.05), while EE did not differ. TT₃ was negatively correlated with consecutive hours of negative EB (R = -0.604, p = 0.049) and positively correlated to hours in EB (R = 0.740, p = 0.009) in those exhibiting metabolic suppression (n = 12). In individuals in TDEB (n = 21), "backloaders" (consumption of ≥50% daily kcals at or after 1700 h) had lower TT₃ (79.3 ng/dL vs 92.9 ng/dL, p = 0.009) than "nonbackloaders" (n = 12). WDEB analyses indicate a greater risk of energy deficiency in females and may capture indices of metabolic compensation not evident with EB analyses alone.

Anti-COVID-19 measures threaten our healthy body weight: Changes in sleep and external synchronizers of circadian clocks during confinement

BACKGROUND & AIMS

Emergency measures in the face of the recent COVID-19 pandemic have been different among countries, although most have opted for confinement and restrictions on social contact. These measures have generated lifestyle changes with potential effects on individuals' health. The disturbances in daily routines due to confinement and remote work have impacted circadian rhythms and energy balance; however, the consequences of these disruptions have not been studied in depth. The objective was to evaluate the impact of 12-week confinement on body weight, considering changes in several external synchronizers of the biological clock.

METHODS

The participants, 521 university students (16-35 years), responded to 52 questions oriented to determine light exposure, sleep patterns, sedentary lifestyle, and eating times.

RESULTS

We found a reduction in sunlight exposure and sleep duration, an increment in sedentarism and screen exposure, and a delay in the timing of the main meals and sleep in the whole cohort. These behavioral changes were associated with a twofold increase in obesity. Subjects who increased their sedentary hours and shortened their sleep to a higher degree were those who gained more bodyweight. The most influential factors in body weight variation during confinement were sleep duration, physical activity (sedentarism), and light (timing of screen exposure). The mediation model explained 6% of the total body weight variation.

CONCLUSIONS

Results support a significant impact of confinement on several external synchronizers of the biological clock and on body weight. Health-related recommendations during the pandemic must include behavioral recommendations to mitigate the adverse effects on the biological clock.

Effects of Time-Restricted Feeding and Ramadan Fasting on Body Weight, Body Composition, Glucose Responses, and Insulin Resistance: A Systematic Review of Randomized Controlled Trials

Time-restricted feeding (TRF) and Ramadan fasting (RF) have been recently associated with several health outcomes. However, it is not yet clear if they are superior to existing treatments in terms of glucose metabolism, insulin action, and weight loss. This review aims to summarize the current data on the effects of these regimes on body weight, body composition, and glycemia. An electronic search was conducted in PUBMED and SCOPUS databases up to August 2022. Twenty-four records met the inclusion criteria and underwent a risk-of-bias assessment. The main outcomes were: (a) TRF may result in moderate weight loss in individuals with overweight/obesity; when TRF is combined with caloric restriction, weight loss is >5% of the initial body weight, (b) 14 h of fasting may be as effective as 16 h in terms of weight loss, and (c) TRF may lead to improved insulin sensitivity and glycemic responses/variability throughout the day in individuals with overweight/obesity. Concerning RF, only two studies were available and thus, conclusions were not drawn. TRF may be an effective nutritional approach for weight loss, and the amelioration of glycemic control and insulin sensitivity in individuals with overweight/obesity. However, more long-term, well-designed studies are needed.

Relationship between energy balance-related behaviors and personal and family factors in overweight/obese primary school students aged 10-12 years in China: a cross-sectional study

Background

Increasing rates of childhood obesity worldwide are a serious threat to the health of school-aged children. Unhealthy behavioral habits are modifiable factors in the control of childhood obesity, and personal and family factors are key influencing factors of behavioral habits in school-aged children. This study assessed the relationship between overweight/obesity, energy balance-related behaviors (EBRB), and their influencing factors in school-aged children.

Methods

This cross-sectional survey included 4412 primary school-aged (10–12 years) students who underwent body tests and were selected through stratified sampling in the Northeast, North, Northwest, and Southwest regions of China from March to July 2021. Independent sample t test was used to compare differences between behaviors and influencing factors of energy balance among overweight/obesity and normal weight students. Logistic regression analysis was used to assess the influence of EBRB on body shape. Multiple linear regression was used to assess the influence of personal and family factors on EBRB effects.

Results

Compared with normal-weight students, number of breakfasts consumed per week by overweight/obese students was significantly lower (p < 0.01), and weekly screen-viewing time was significantly longer (p < 0.01). Overweight/obese students’ health beliefs, parental subjective norms, parental modelling, parental practices, and home availability scores increased significantly in terms of beverage consumption behavior (p < 0.01 or p < 0.05). Attitude, health beliefs, self-efficacy, parental subjective norms, and parental support scores decreased significantly in terms of breakfast consumption (p < 0.01 or p < 0.05). Health belief scores on physical activity increased significantly (p < 0.01), while preference and autonomy scores decreased significantly (p < 0.01). Health beliefs, parental subjective norms, and parental practices scores of screen-viewing activities increased significantly (p < 0.01 or p < 0.05). Breakfast consumption (odds ratio [OR]: 0.911; 95% confidence interval [CI]: 0.870–0.954) and screen-viewing activities (OR:1.055; 95% CI: 1.030–1.080) correlated negatively and positively with overweight/obesity, respectively. The main influencing factors of breakfast behavior in overweight/obese students were self-efficacy (0.14), preference (0.11), attitude (0.07), home availability (0.18), and parent modelling (0.09); those for screen-viewing behavior were preference (0.19), self-efficacy (− 0.15), parental practices (0.13), and parental subjective norm (0.12).

Conclusions

Irregular breakfast consumption and excessive screen-viewing time are key EBRB associated with overweight/obesity among these Chinese participants. Their unhealthy breakfast consumption and screen-viewing activities result from a combination of personal and family factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-14238-x.

Timing of daily calorie loading affects appetite and hunger responses without changes in energy metabolism in healthy subjects with obesity

Morning loaded calorie intake in humans has been advocated as a dietary strategy to improve weight loss. This is also supported by animal studies suggesting time of eating can prevent weight gain. However, the underlying mechanisms through which timing of eating could promote weight loss in humans are unclear. In a randomized crossover trial (NCT03305237), 30 subjects with obesity/overweight underwent two 4-week calorie-restricted but isoenergetic weight loss diets, with morning loaded or evening loaded calories (45%:35%:20% versus 20%:35%:45% calories at breakfast, lunch, and dinner, respectively). We demonstrate no differences in total daily energy expenditure or resting metabolic rate related to the timing of calorie distribution, and no difference in weight loss. Participants consuming the morning loaded diet reported significantly lower hunger. Thus, morning loaded intake (big breakfast) may assist with compliance to weight loss regime through a greater suppression of appetite.

Ultra-processed food consumption and dietary, lifestyle and social determinants: a path analysis in Brazilian graduates (CUME project)

OBJECTIVE

To explore the relationship between ultra-processed foods (UPF) consumption and dietary, lifestyle and social determinants using pathway analysis in the baseline of the Cohort of Universities of Minas Gerais (CUME project).

DESIGN

Cross-sectional study, in which path analysis was used to estimate direct and indirect effects of dietary practices, sleep, time on the computer and professional status on UPF consumption.

SETTING

Data were collected in 2016, through an online questionnaire composed of sociodemographic, anthropometric, lifestyle and dietary practices questions, and a FFQ.

PARTICIPANTS

Baseline participants from the CUME Project (n 2826), adults who graduated from Universidade Federal de Viçosa or Universidade Federal de Minas Gerais, Brazil.

RESULTS

Being employed (P = 0·024), the time spent on the computer (P = 0·031) and the frequency of fried food intake (P < 0·001) were positively and directly associated with UPF consumption, whereas the sleep duration (P = 0·007) and the number of meals per d (P < 0·001) were negatively and directly associated with UPF consumption. Indirect effects were observed between being employed, mediated by the sleep duration (P = 0·032) and fried food intake (P = 0·005), whereas being a student is mediated by the time on the computer (P = 0·048).

CONCLUSION

The time spent on the computer, sleep duration and fried food consumption showed direct effects on UPF consumption. They also acted as mediators on the relationship between professional status and UPF consumption. Besides, the number of meals eaten each day also was directly associated with UPF consumption.

Timed restricted feeding cycles drive daily rhythms in female rats maintained in constant light but only partially restore the estrous cycle

Light at night is an emergent problem for modern society. Rodents exposed to light at night develop a loss of circadian rhythms, which leads to increased adiposity, altered immune response, and increased growth of tumors. In female rats, constant light (LL) eliminates the estrous cycle leading to a state of persistent estrus. The suprachiasmatic nucleus (SCN) drives circadian rhythms, and it interacts with the neuroendocrine network necessary for reproductive function. Timed restricted feeding (RF) exerts a powerful entraining influence on the circadian system, and it can influence the SCN activity and can restore rhythmicity or accelerate re-entrainment in experimental conditions of shift work or jet lag. The present study explored RF in female rats exposed to LL, with the hypothesis that this cyclic condition can rescue or prevent the loss of daily rhythms and benefit the expression of the estrous cycle. Two different feeding schedules were explored: 1. A 12-h food/12-h fasting schedule applied to arrhythmic rats after 3 weeks in LL, visualized as a rescue strategy (LL + RFR, 3 weeks), or applied simultaneously with the first day of LL as a preventive strategy (LL + RFP, 6 weeks). 2. A 12-h window of food intake with food given in four distributed pulses (every 3 h), applied after 3 weeks in LL, as a rescue strategy (LL + PR, 3 weeks) or applied simultaneously with the first day of LL as a preventive strategy (LL + PP, 6 weeks). Here, we present evidence that scheduled feeding can drive daily rhythms of activity and temperature in rats exposed to LL. However, the protocol of distributed feeding pulses was more efficient to restore the day–night activity and core temperature as well as the c-Fos day–night change in the SCN. Likewise, the distributed feeding partially restored the estrous cycle and the ovary morphology under LL condition. Data here provided indicate that the 12-h feeding/12-h fasting window determines the rest-activity cycle and can benefit directly the circadian and reproductive function. Moreover, this effect is stronger when food is distributed along the 12 h of subjective night.

Circadian mechanism disruption is associated with dysregulation of inflammatory and immune responses: a systematic review

The circadian rhythms are regulated by the circadian clock which is under the control of suprachiasmatic nucleus of hypothalamus. The central and peripheral clocks on different tissue together synchronize to form circadian system. Factors disrupt the circadian rhythm, such as irregular eating patterns, sleep/wake time, night shift work and temperature. Due to the misalignment of central clock components, it has been recognized as the pathophysiology of lifestyle-related diseases mediated by the inflammation such as diabetes, obesity, neurological disorder and hormonal imbalance. Also we discuss the therapeutic effect of time-restricted feeding over diabetes and obesity caused by miscommunication between central and peripheral clock. The genetic and epigenetic changes involve due to the deregulation of circadian system. The aim of the present review is to discuss the circadian mechanisms that are involved in the complex interaction between host and external factors and its disruption is associated with deregulation of inflammatory and immune responses. Hence, we need to understand the mechanism of functioning of our biological clocks so that it helps us treat health-related problems such as jet lags, sleep disorders due to night-time shift work, obesity and mental disturbances. We hope minimal cost behavioural and lifestyle changes can improve circadian rhythms and presumably provide a better health.

Changes in dietary intake, chronotype and sleep pattern upon Ramadan among healthy adults in Jeddah, Saudi Arabia: A prospective study

Background

Notable lifestyle changes can occur in Ramadan due to the sudden shift in eating routine with fasting during daylight hours. This study aimed to examine the changes in dietary intakes, chronotype, sleep pattern, and physical activity level before and during Ramadan in healthy adults.

Methods

This study was conducted in Jeddah city, Saudi Arabia, and convenience sampling was used. To compare dietary, chronotype and sleep pattern changes before and during Ramadan, data were collected in two separate periods: the first period was 2 months before Ramadan, and the second period was during the last 3 weeks of Ramadan. Dietary intake was assessed using 24-h food recall and chronotype using Morningness-Eveningness Questionnaire. Daytime sleepiness and sleep duration were assessed using the Epworth sleepiness scale and a sleep diary for seven consecutive days, respectively. Anthropometric measurements were also taken across the study periods.

Results

A total of 115 adults (96 females and 19 males) were included in the study. Significant increases in daily calorie and carbohydrate intakes during Ramadan than before Ramadan were noted (calorie intake: 1,482.9 ± 536.4 kcal/day before Ramdan vs. 1,635.5 ± 635.1 kcal/day during Ramadan; carbohydrate intake: 180.8 ± 72.1 g/day before Ramadan vs. 202.6 ± 88.7 g/day during Ramadan; p < 0.05). Chronotypes and daytime sleepiness were also associated significantly with Ramadan fasting. A significant slight reduction in body weight during Ramadan was observed (66.4 ± 18.1 kg before Ramdan vs. 66.1 ± 17.8 kg before Ramadan and during Ramadan, respectively; p < 0.05).

Conclusion

This study indicates that Ramadan diurnal fasting was associated with greater calorie and carbohydrate intake, changes in chronotype, and daytime sleepiness. The study also suggests that Ramadan diurnal fasting model may be a promising weight loss strategy.

Application of a composite scoring protocol to identify factors that contribute to the risk of overweight and obesity in Irish children

BACKGROUND

Investigations into the main drivers of childhood obesity are vital to implement effective interventions to halt the global rise in levels. The use of a composite score may help to identify children most at risk of overweight/obesity.

OBJECTIVES

To investigate the cumulative impact of factors associated with overweight/obesity risk in children.

METHODS

Data were analysed from the Irish National Children's Food Survey II which included 600 children, aged 5-12-years. The risk factors examined included social class, parental, early life, lifestyle, and dietary components. A composite score was calculated which ranged from 0 (no risk factors for overweight/obesity) to 4 (4 risk factors for overweight/obesity).

RESULTS

In model 1 (%BF) the four factors associated with overweight/obesity risk were having a parent with overweight/obesity (odds ratio 3.1; 95% confidence interval 1.9-4.8), having a high birth weight of ≥4 kg (2.5; 1.6-3.9), being from a low social class (2.3; 1.4-3.8) and low physical activity (1.9; 1.2-2.8). Children who scored 3-4 points on the composite score had a 10-fold (10.0; 4.2-23.9) increased risk of overweight/obesity compared to those with 0 points, a sevenfold (7.2; 3.9-13.5) increased risk compared to those with 1 point and a threefold (2.6; 1.4-4.8) increased risk compared to those with 2 points, with similar results observed in model 2 (BMI).

CONCLUSION

The use of a composite score is a beneficial means of identifying children at risk of overweight/obesity and may prove useful in the development of effective interventions to tackle childhood obesity.

Relationship among chrononutrition, sleep, and glycemic control in women with gestational diabetes mellitus: a randomized controlled trial

BACKGROUND

Gestational diabetes mellitus is associated with an increased risk of maternal, fetal, and neonatal morbidities. Chronobiological disorders have recently been identified as risk factors for those morbidities. The disorders include chrononutritional disorders related to meal frequency and content according to the sleep-wake cycle, sleep disorders related to sleep quality, and chrono-obesity disorders, such as abnormal weight gain because of sleep deprivation and time of eating.

OBJECTIVE

This study aimed to assess whether a chrononutritional and sleep hygiene intervention can improve maternal glycemic control and reduce the proportion of large-for-gestational-age newborns among women with gestational diabetes mellitus.

STUDY DESIGN

This randomized controlled trial included 103 women with gestational diabetes mellitus who were carrying a singleton fetus and assigned to either the intervention group (n=33) or the control group (n=70). The intervention group was assigned to a chrononutrition and sleep hygiene program, in addition to the usual care for gestational diabetes mellitus, from the time of diabetes mellitus diagnosis to birth, whereas the control group received the usual gestational diabetes mellitus care.

RESULTS

The chrononutritional and sleep hygiene intervention significantly reduced the proportion of women with suboptimal glycemic control (<80% of the plasma glucose values at target), after adjustment for maternal age, prepregnancy body mass index, gravidity, history of gestational diabetes mellitus, and large for gestational age (relative risk, 0.28; 95% confidence interval, 0.18-0.81). The effect of the intervention on balancing maternal glycemic control was mainly because of the decreased carbohydrate intake in the evening interval of the day (relative risk, 0.8; 95% confidence interval, 0.64-0.99). However, the intervention had no effect on the proportion of large-for-gestational-age newborns.

CONCLUSION

The chrononutritional and sleep hygiene intervention can improve maternal glycemic control.

Influence of CLOCK Gene Variants on Weight Response after Bariatric Surgery

The Circadian Locomotor Output Cycles Kaput (CLOCK) gene has been linked to metabolic dysfunction and obesity. The purpose of this study was to analyze the association between single nucleotide polymorphisms (SNPs) of CLOCK gene with obesity and with long-term weight response after different bariatric surgery (BS) techniques. The cohort includes 375 patients with morbid obesity (MO) and 230 controls. In the association study of SNPs with weight response we combined several variables as phenotype at 6 years after surgery. The study protocol was registered in ISRCTN (ID80961259). The analysis of the selected SNPs was performed by allelic discrimination using Taqman^® probes. The genotype association study was performed using the SNPStats program, with comparisons adjusted for sex, age, initial Body Mass Index, type 2 diabetes and hypertension diagnosis, and type of surgery. In the case-control study two of three SNPs were significantly associated with MO. The variant rs1801260 had a protective effect for MO whereas the TT genotype of rs3749474 variant had the strongest association with MO (OR = 2.25 (1.39–3.66); p = 0.0006). In the linear regression analysis both variants showed significant association with long-term weight loss and weight regain after BS, independently of the pre-surgery patient profile.