Variability in Daily Eating Patterns and Eating Jetlag Are Associated With Worsened Cardiometabolic Risk Profiles in the American Heart Association Go Red for Women Strategically Focused Research Network

Irregular breakfast eating in type 2 diabetes mellitus is associated with greater social jetlag and poorer metabolic health

Circadian disruption, arising from conflict between internal circadian time and behavioural sleep-wake and fasting-feeding rhythms, may contribute to the prevalence of type 2 diabetes mellitus and disease severity. Previous studies have demonstrated a link between irregular breakfast eating and poorer metabolic health. We aimed to further explore the relationships between breakfast habits, circadian misalignment (social jetlag), and metabolic parameters in a cohort of adult participants with type 2 diabetes mellitus. A total of 330 adult participants with type 2 diabetes mellitus attending for routine clinical review completed structured questionnaires to assess habitual sleep timing, chronotype, and social jetlag. Statistical analysis was via inferential groupwise approaches and path analysis to establish interdependencies of effects of social jetlag, chronotype, and breakfast eating regularity on HbA1c. 22.7% of the participants reported eating breakfast five times or fewer a week, and were categorised as irregular breakfast eaters. Compared with those who ate breakfast six or seven times a week, irregular breakfast eaters had significantly higher HbA1c and diastolic blood pressure, were younger and had greater social jetlag. In the path analysis, irregular breakfast eating exerted a direct effect on HbA1c, whilst social jetlag exerted only an indirect effect on HbA1c through breakfast eating regularity. Chronotype did not exert any effect on HbA1c, but did exert an indirect effect on breakfast eating regularity via social jetlag. Our results showed that adult participants with type 2 diabetes mellitus, who ate breakfast irregularly had poorer metabolic health and greater social jetlag. The relationship between social jetlag and glycaemic control appears to be mediated through breakfast eating habits.

Advancing Chrononutrition for Cardiometabolic Health: A 2023 National Heart, Lung, and Blood Institute Workshop Report

The circadian system maintains optimal biological functions at the appropriate time of day, and the disruption of this organization can contribute to the pathogenesis of cardiometabolic disorders. The timing of eating is a prominent external time cue that influences the circadian system. "Chrononutrition" is an emerging dimension of nutrition and active area of research that examines how timing-related aspects of eating and nutrition impact circadian rhythms, biological processes, and disease pathogenesis. There is evidence to support chrononutrition as a form of chronotherapy, such that optimizing the timing of eating may serve as an actionable strategy to improve cardiometabolic health. This report summarizes key information from the National Heart, Lung, and Blood Institute's virtual workshop entitled "Chrononutrition: Elucidating the Role of Circadian Biology and Meal Timing in Cardiometabolic Health," which convened on May 2 to 3, 2023, to review current literature and identify critical knowledge gaps and research opportunities. The speakers presented evidence highlighting the impact on cardiometabolic health of earlier and shorter eating windows and more consistent day-to-day eating patterns. The multidimensionality of chrononutrition was a common theme, as it encompasses multiple facets of eating along with the timing of other behaviors including sleep and physical activity. Advancing the emerging field of chrononutrition will require: (1) standardization of terminology and metrics; (2) scalable and precise tools for real-world settings; (3) consideration of individual differences that may act as effect modifiers; and (4) deeper understanding of social, behavioral, and cultural influences. Ultimately, there is great potential for circadian-based dietary interventions to improve cardiometabolic health.

The effects of chrononutrition, chronotype and sleep behavior variabilities on adiposity traits and appetite sensations among students and staff of a Malaysian university

We investigated the association of chrononutrition, sleep behavior, and chronotype with adiposity and appetite sensations among 220 Malaysian adults (M/F = 57/163; aged 22.02   ±   5.19). Meal times, dietary intake, and appetite sensations (before and after meals) were recorded for two weekdays and one weekend. Sleep behavior was tracked objectively via activity wristband, chronotype was assessed by the Morningness-Eveningness Questionnaire, and anthropometrics/body compositions were measured. Overall participants had significantly later breakfast, lunch, eating midpoint, wake up time, sleep duration, compared to weekdays. Those who belonged to the delay eating jetlag group had significantly higher weekday, but lower weekend eating windows. Larger caloric intake later in the day was significantly associated with lower body mass and adiposity. Delay lunch jetlag class was significantly associated with higher waist-hip ratio. Delayed morning and afternoon chrononutrition behaviors were associated with higher hunger and eating thoughts, and lower fullness sensations pre- and post-meals. Morningness was associated with lower satisfaction and fullness sensations post-breakfast, but higher same sensations pre-dinner. In conclusion, larger caloric intake later in the day and advanced lunch jetlag led to lower adiposity, while delayed chrononutrition behaviours were associated with higher pre- and post-meal appetite sensations.

Chrononutrition behaviors in relation to diet quality and obesity: do dietary assessment methods and energy intake misreporting matter?

BACKGROUND

Inconsistent epidemiologic findings on the associations of chrononutrition behaviors with diet quality and adiposity measures may be due to the use of different dietary assessment methodologies and a lack of consideration of dietary misreporting. We aimed to investigate the associations by using questionnaires and diaries, with adjustment for energy intake (EI) misreporting.

METHODS

This cross-sectional study included 1047 Japanese adults aged 20-69 years. We used the Chrono-Nutrition Behavior Questionnaire (CNBQ) or 11-day diaries to assess chrononutrition behaviors (meal frequency, snack frequency, total eating frequency, timing of first eating occasion, timing of last eating occasion, duration of eating window, and eating midpoint) for workdays and non-workdays separately. Eating jetlag was defined as the eating midpoint difference between workdays and non-workdays. Diet quality was assessed using the Healthy Eating Index-2020, based on the Meal-based Diet History Questionnaire (MDHQ) or 4-day weighed food diaries. EI misreporting was evaluated using the Goldberg cut-off principle.

RESULTS

Using questionnaire data (CNBQ and MDHQ), we found inverse associations of snack and total eating frequencies, timing of last eating occasion, eating midpoint, and eating jetlag with diet quality (P < 0.05), irrespective of adjustment for EI misreporting. Also, we found positive associations of meal, snack, and total eating frequencies and duration of eating window with the prevalence of general obesity (body mass index ≥ 25 kg/m2), abdominal obesity (waist circumference ≥ 90 cm for males; ≥ 80 cm for females), or both; many of these associations were only evident (P < 0.05) after adjustment for EI misreporting. In contrast, using diary data, we found no associations between chrononutrition behaviors and diet quality, general obesity, or abdominal obesity, regardless of adjustment for EI misreporting (except for inverse associations of timings of first and last eating occasions and eating midpoint on workdays with diet quality).

CONCLUSIONS

The associations of chrononutrition behaviors with diet quality and obesity were dependent on the methodology used to assess these behaviors. Adjustment for EI misreporting radically changed only the associations with obesity in the questionnaire-based analysis. These findings suggest the importance of careful consideration of dietary assessment method selection and EI misreporting in chrononutrition research.

Associations of >1-h compared with 1-h meal timing variability (eating jetlag) with plasma glycemic parameters and continuous glucose monitoring measures among pregnant females: a prospective cohort study

BACKGROUND

Eating jetlag (EJL), the difference in eating times between weekdays and weekends, disrupts circadian alignment and may affect metabolic health. However, its influence on glucose tolerance and continuous glucose monitoring (CGM) during pregnancy remains unknown.

OBJECTIVES

We aimed to investigate the associations between EJL and glycemic parameters during pregnancy.

METHODS

This secondary analysis was conducted on a cohort of 248 healthy pregnant females from Singapore. EJL, derived from 4-d food diaries at 20 wk of gestation, was the absolute difference in average meal times between weekdays and weekends for the first (EJLfirst) and last (EJLlast) meals and categorized as ≤1 h (reference) or >1 h. Primary outcomes at 25 wk of gestation included results from the 75-g oral glucose tolerance test, fasting insulin, homeostasis model assessment of insulin resistance (HOMA2-IR), and β-cell function (HOMA2-%B). Secondary outcomes at 20 wk of gestation included glycemic control and variability measured over 10 d using CGM. Skewed glycemic variables were log-transformed for normality, and associations between EJL and glycemic outcomes were analyzed using multivariable regressions.

RESULTS

After adjusting for baseline sociodemographic, lifestyle, and dietary factors, EJLlast >1 h was associated with higher fasting insulin [geometric mean ratio (95% confidence intervals): 1.21 (1.05, 1.39)], HOMA2-IR [1.21 (1.05, 1.39)], HOMA2-%B [1.11 (1.01, 1.22)], and CGM-based measures, including mean glucose [1.05 (1.00, 1.09)], J-index [1.11 (1.01, 1.22)], and glucose management indicator [1.03 (1.00, 1.06)]. EJLfirst >1 h was associated with higher CGM-based mean amplitude of glycemic excursions (MAGE) [1.09 (1.01, 1.19)]. For CGM-based glycemic variability outcomes (standard deviation, coefficient of variation [CV], MAGE), there were interactions between EJLfirst and 1) diet quality [adherence to Dietary Approaches to Stop Hypertension (DASH)] (P-interactions = 0.06-0.09), and 2) prepregnancy body mass index (BMI) (P-interaction=0.07 for CV). In females with a prepregnancy BMI ≥23 kg/m2 and low diet quality (DASH score ≤median), EJLfirst >1 h was associated with higher CGM-based glycemic variability.

CONCLUSIONS

EJL was associated with unfavorable glycemic parameters during pregnancy. Dietary interventions could promote consistent meal timing, especially in higher risk groups with suboptimal nutritional status. This trial was registered at clinicaltrials.gov as NCT03803345.

Association between behavioral jet lag with subjective and objective circadian rhythm among Chinese young adults

BACKGROUND

Behavioral jet lags (social and eating jet lag), the difference in sleep and eating time between weekdays and weekends, are ubiquitous in modern society. However, evidence on the effects of behavioral jet lags on circadian rhythm is limited.

METHODS

Social jet lag was assessed using wrist-worn accelerometers. Eating jet lag was measured through Tencent online form with the method of ecological momentary assessment. Total jet lag was calculated as social jet lag plus eating jet lag. Participants were divided into 3 behavioral jet lag patterns: low (both social and eating jet lag < 1h), medium (social or eating jet lag ≥ 1h), and high (both social and eating jet lag ≥ 1h). Subjective and objective circadian rhythm were assessed by reduced Morningness-Eveningness Questionnaire (rMEQ)-based chronotype and the dim light melatonin onset (DLMO) time in 7 saliva samples, respectively.

RESULTS

The mean age of the sample (n = 140) was 20.7 ± 0.8 years, and 60% were women. Compared to low behavioral jet lag group, medium and high behavioral jet lag group exhibited lower rMEQ score and later DLMO time. Each hour increase in social jet lag was associated with 2.27 point-decrease of rMEQ score, and 24 min-delay of DLMO time; each hour increase in eating jet lag was associated with 1.71 point-decrease of rMEQ score, and 28 min-delay of DLMO time; each hour increase in total jet lag was associated with 1.08 point-decrease of rMEQ score, and 17 min-delay of DLMO time (all P-values <0.05). Additionally, social jet lag explained 6.7% of the variance in the timing of DLMO, which was higher than eating jet lag (4.2%).

CONCLUSION

Higher behavioral jet lags were significantly associated with increased risk of circadian disruption among young adults. Maintaining consistency in daily behavioral cycles may be an effective intervention for the prevention of circadian disruption.

Habitual food consumption, eating behavior and meal-timing among Jordanian adults with elevated Blood pressure: a cross-sectional population-based study

BACKGROUND

The prevalence of elevated blood pressure (BP) has been raised worldwide. Food consumption, eating habits, and nutritional lifestyle related to meal timing, skipping meals, and meal contents have recently received more attention in studies on BP and metabolic syndrome. Purpose: This study evaluated the association between habitual food consumption, eating behavior, and meal timing with BP among Jordanian adults.

METHODS

A cross-sectional study included 771 Jordanian adults. A food frequency questionnaire was completed. Data about eating habits, meal timing, and emotional eating were collected. BP was measured.

RESULTS

The prevalence of less than recommended intake of vegetables, milk, protein, and fruits was higher in participants with elevated BP (69.2%, 90.2%, 58.9%, and 25.5%, respectively) as compared to the normal BP group (p < 0.001). Consuming vegetables and milk less than the recommended was reported to significantly increase the likelihood of elevated BP by OR= (1.60, and 2.75 (95%CI: 1.06-2.40; 1.62-4.66). Hence, consuming more than recommended fruit reduced the risk of elevated BP by OR = 0.56 (95%CI: 0.38-0.82). A 63.2% of elevated BP participants have three meals daily, a higher percentage of intake of one (23.5%) and two (45.7%) snacks. However, they had a higher percentage of morning eaters (50.7%), had lunch between 1:00-6:00 PM (92.7%), and had dinner between 6:00 and 9:00 PM (68.1%).

CONCLUSIONS

Although Jordanian adults with elevated BP appear to have healthy eating habits and meal timing and frequency, their habitual food consumption falls short of the daily recommendations for milk, fruits, vegetables, and protein.

Association between social jetlag and weight and fat reduction in dieting

Objectives: Social jetlag (SJL), the discrepancy between an individual's inherent circadian rhythm and external social schedule, is associated with obesity. This study aimed to investigate whether SJL also influences body weight and body fat loss during dieting. Methods: This was an observational study from 2015 to 2018 with participants who had joined an exercise and nutrition program at a private personal training gym. Data from 11,829 individuals provided by the gym along with their sleep logs were analyzed. Differences in change in body mass index (BMI) and body fat percentage (%body fat) were compared by the degree of SJL. Regression was conducted for the change in BMI and %body fat on SJL, adjusted for gender, age, engagement duration in the program, initial BMI, initial %body fat, chronotype, and dietary intakes. Results: The subjects comprised 3,696 men and 8,133 women with a mean age of 40.4 years. Greater SJL was associated with a lower efficacy of BMI and %body fat reduction. The change in BMI (+ 0.56 / hour: SJL) and %body fat (+ 1.40 / hour: SJL) was associated with SJL after adjusting for each variable including dietary intake. Conclusion: SJL was associated with the effect of exercise and nutrition instruction on BMI and body fat reduction, even after adjustment for covariates related to dietary intake. Maintaining consistent sleep-wake rhythms may be crucial for enhancing the efficacy of weight loss programs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41105-024-00539-8.

Associations between temporal eating patterns and body composition in young adults: a cross-sectional study

PURPOSE

The aim of this study was to examine the associations between body composition and temporal eating patterns, including time of first eating occasion, time of last eating occasion, eating window, and eating jet lag (the variability in meal timing between weekdays and weekends).

METHODS

A total of 131 participants were included in the study. Temporal eating pattern information was collected through consecutive 7-day eat timing questionnaires and photographic food records. Body composition was assessed by bioelectrical impedance analysis. Multiple linear regression models were used to evaluate the relationships of temporal eating patterns with body composition, and age was adjusted. Eating midpoint was additionally adjusted in the analysis of eating window.

RESULTS

On weekdays, both later first eating occasion and last eating occasion were associated with lower lean mass, and longer eating window was associated with lower body fat percentage. On weekends, both later first eating occasion and last eating occasion were associated with lower lean mass, and longer eating window was associated with higher FFMI. Longer first eating occasion jet lag was associated with lower lean mass.

CONCLUSION

Our study suggested that earlier and more regular eating patterns may have a benefit on body composition.

Chrononutrition and Cardiometabolic Health: An Overview of Epidemiological Evidence and Key Future Research Directions

Chrononutrition is a rapidly evolving field of nutritional epidemiology that addresses the complex relationship between temporal eating patterns, circadian rhythms, and metabolic health, but most prior research has focused on the cardiometabolic consequences of time-restricted feeding and intermittent fasting. The purpose of this topical review is to summarize epidemiological evidence from observational and intervention studies regarding the role of chrononutrition metrics related to eating timing and regularity in cardiometabolic health preservation and cardiovascular disease prevention. Observational studies are limited due to the lack of time-stamped diet data in most population-based studies. Findings from cohort studies generally indicate that breakfast skipping or the later timing of the first eating occasion, a later lunch and dinner, and a greater proportion of caloric intake consumed in the evening are associated with adverse cardiometabolic outcomes, including higher risk for coronary heart disease, hypertension, type 2 diabetes, obesity, dyslipidemia, and systemic inflammation. Randomized controlled trials are also limited, as most in the field of chrononutrition focus on the cardiometabolic consequences of time-restricted feeding. Overall, interventions that shift eating timing patterns to earlier in the day and that restrict evening caloric intake tend to have protective effects on cardiometabolic health, but small sample sizes and short follow-up are notable limitations. Innovation in dietary assessment approaches, to develop low-cost validated tools with acceptable participant burden that reliably capture chrononutrition metrics, is needed for advancing observational evidence. Culturally responsive pragmatic intervention studies with sufficiently large and representative samples are needed to understand the impact of fixed and earlier eating timing schedules on cardiometabolic health. Additional research is warranted to understand the modifiable determinants of temporal eating patterns, to investigate the role of chrononutrition in the context of other dimensions of diet (quantity, quality, and food and nutrition security) in achieving cardiometabolic health equity, and to elucidate underlying physiological mechanisms.

The association between diet quality and chrononutritional patterns in young adults

PURPOSE

Young adults eat erratically and later in the day which may impact weight and cardiometabolic health. This cross-sectional study examined relationships between chrononutritional patterns and diet quality in two young adult populations: a university and community sample.

METHODS

Three days of dietary data were collected including food images captured using wearable cameras. Chrononutritional variables were extracted: time of first and last eating occasions, caloric midpoint (time at which 50% of daily energy was consumed), number of eating occasions per day, eating window, day-to-day variability of the above metrics, and evening eating (≥20:00h). The Healthy Eating Index for Australian Adults scored diet quality. Statistical analyses controlled for gender, body mass index, and socio-economic status.

RESULTS

No significant associations between chrononutritional patterns and diet quality were found for all participants (n = 95). However, differences in diet quality were found between university (n = 54) and community (n = 41) samples with average diet quality scores of 59.1 (SD 9.7) and 47.3 (SD 14.4), respectively. Of those who extended eating ≥20:00 h, university participants had better diet quality (62.9±SE 2.5 vs. 44.3±SE 2.3, p < 0.001) and discretionary scores (7.9±SE 0.9 vs. 1.6±SE 0.6, p < 0.001) than community participants. University participants consumed predominately healthful dinners and fruit ≥20:00h whereas community participants consumed predominately discretionary foods.

CONCLUSION

For the general young adult population, meal timing needs to be considered. Food choices made by this cohort may be poorer during evenings when the desire for energy-dense nutrient-poor foods is stronger. However, meal timing may be less relevant for young adults who already engage in healthy dietary patterns.

Effects of time-restricted eating on intrahepatic fat and metabolic health among patients with nonalcoholic fatty liver disease

OBJECTIVE

The study's objective was to explore whether early time-restricted eating (eTRE) and late time-restricted eating (lTRE) have different impacts on intrahepatic fat and metabolic health among patients with nonalcoholic fatty liver disease (NAFLD).

METHODS

This is an 8-week, randomized, parallel-arm, open-label trial. Forty eligible patients were randomly assigned to eTRE (eating between 8:00 a.m. and 4:00 p.m.) or lTRE (eating between 12:00 p.m. and 8:00 p.m.). The primary outcome was the change of intrahepatic fat measured by magnetic resonance image-derived proton density fat fraction. Secondary outcomes included changes in weight, body composition, liver function, and cardiometabolic factors.

RESULTS

Forty participants who underwent randomization completed the trial (mean age: 38.25 years). The eTRE group had a -3.24% absolute reduction of intrahepatic fat (95% CI: -4.55% to -1.92%) and there was a -3.51% absolute reduction for the lTRE group (95% CI: -5.10% to -1.92%). Changes in intrahepatic fat were not statistically different between the two groups. Both the eTRE and lTRE groups had similar and significant reductions in weight, visceral fat, subcutaneous fat, liver enzymes, and glucose regulatory indicators.

CONCLUSIONS

Among patients with NAFLD, both eTRE and lTRE induced significant reductions in intrahepatic fat and improvements in body composition, liver function, and metabolic health with similar magnitude. These findings suggest that eTRE and lTRE are comparable and feasible strategies for NAFLD management.

Lifestyle factors, dietary patterns, and social determinants of social and eating jetlag: A cross-sectional survey

Social jetlag (SJL) and, more recently, eating jetlag have been linked with an increased risk of non-communicable diseases. Here we aim to investigate lifestyle factors (diet, eating behavior, smoking, perceived stress, time spent sedentary/day) and social determinants (education level, employment status, and place of residence) associated with SJL corrected for sleep duration (SJLsc) and eating jetlag. Self-declared data on age, gender, lifestyle, and eating behavior were collected online from March 2021 to February 2022 of 432 adults. Principal component analysis was used to extract three dietary patterns (Prudent, Western, and Risky). Prevalence of SJLsc was 35.2%, with no significant difference between men and women (p = 0.558). Adults with SJLsc had significantly larger eating jetlag (56.0 min vs 41.2 min, p = 0.001). Increasing SJLsc duration was associated with an increased adherence to a Risky dietary pattern (standardized β coefficient = .165, p = 0.012); increasing eating jetlag duration was associated with an increased adherence to a Western dietary pattern (standardized β coefficient = .127, p = 0.039) and a shorter sleep duration (standardized βcoefficient = -0.147, p = 0.011). Among social determinants analyzed, only being a student or employed was associated with eating jetlag (standardized β coefficient = 0.125, p = 0.044), while none displayed any relationship with SJLsc. Our survey provides evidence on a risky behavior among young persons with SJLsc and eating jetlag, characterized by a higher alcohol consumption, and a diet rich in processed meat and high-fat food, eating during nights, and shorter sleep duration with potential long-term negative health outcomes.

Dietary circadian rhythms and cardiovascular disease risk in the prospective NutriNet-Santé cohort

Daily eating/fasting cycles synchronise circadian peripheral clocks, involved in the regulation of the cardiovascular system. However, the associations of daily meal and fasting timing with cardiovascular disease (CVD) incidence remain unclear. We used data from 103,389 adults in the NutriNet-Santé study. Meal timing and number of eating occasions were estimated from repeated 24 h dietary records. We built multivariable Cox proportional-hazards models to examine their association with the risk of CVD, coronary heart disease and cerebrovascular disease. In this study, having a later first meal (later than 9AM compared to earlier than 8AM) and last meal of the day (later than 9PM compared to earlier than 8PM) was associated with a higher risk of cardiovascular outcomes, especially among women. Our results suggest a potential benefit of adopting earlier eating timing patterns, and coupling a longer nighttime fasting period with an early last meal, rather than breakfast skipping, in CVD prevention.

Changes in eating patterns in response to chronic insufficient sleep and their associations with diet quality: a randomized trial

STUDY OBJECTIVES

Insufficient sleep leads to overconsumption, but the factors contributing to this effect are poorly understood. Therefore, we assessed the influence of prolonged curtailment of sleep on free-living eating patterns linked with overconsumption and explored associations of these eating patterns with diet quality under different sleep conditions.

METHODS

Sixty-five adults (47 females) participated in outpatient randomized crossover studies with two 6-week conditions: adequate sleep (7-9 h/night) and sleep restriction (-1.5 h/night relative to screening). Food records were collected over 3 nonconsecutive days, from which we ascertained data on eating frequency, midpoint, and window and intakes of energy and nutrients. Linear mixed models were used to assess the impact of sleep condition on change in eating pattern (sleep × week interaction) and the relation between eating patterns and dietary intakes (sleep × eating pattern interaction).

RESULTS

Sleep condition impacted the change in eating frequency across weeks, with eating frequency increasing in sleep restriction relative to adequate sleep (β = 0.3 ± 0.1; P = .046). Across conditions, eating more frequently tended to relate to higher energy intakes (β = 60.5 ± 34.6; P = .082). Sleep also influenced the relation of variability in eating midpoint with intakes of saturated fat (β = 6.0 ± 2.1; P = .005), polyunsaturated fat (β = -3.9 ± 2.0; P = .051), and added sugar (β = 17.3 ± 6.2; P = .006), with greater midpoint variability associated with more adverse changes in these diet quality components in sleep restriction vs adequate sleep.

CONCLUSIONS

Chronic short sleep increases eating frequency and adversely influences associations of variability in meal timing with components of diet quality. These findings help to explain how short sleep leads to overconsumption and obesity.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Impact of Sleep Restriction in Women; URL: https://clinicaltrials.gov/ct2/show/NCT02835261; Identifier: NCT02835261 and Name: Impact of Sleep Restriction on Performance in Adults; URL: https://clinicaltrials.gov/ct2/show/NCT02960776; Identifier: NCT02960776.

CITATION

Barragán R, Zuraikat FM, Tam V, RoyChoudhury A, St-Onge M-P. Changes in eating patterns in response to chronic insufficient sleep and their associations with diet quality: a randomized trial. J Clin Sleep Med. 2023;19(11):1867-1875.

Association of Chrononutrition Indices with Anthropometric Parameters, Academic Performance, and Psychoemotional State of Adolescents: A Cross-Sectional Study

Adolescents are an at-risk group for circadian misalignment. The contribution of sleep-wake rhythm instability to the psychoemotional, cognitive, and weight disorders of adolescents has been studied in sufficient detail. At the same time, there is insufficient information about the association between chrononutrition indices and the well-being of adolescents. The aim of this study is to investigate the relationship between chrononutrition indices and academic achievement, psychoemotional state, and anthropometric indicators in adolescents. The study involved 12,759 students in grades 6-11 of secondary schools, aged 14.2 ± 1.7 years old; 57.2% of whom were girls. Participants provided personal data, frequency and time of meals during the day and at night, on weekdays and weekends, and completed the Zung Self-Rating Depression Scale and the Yale Food Addiction Scale. There is a U-shaped association between eating mid-phase (EPFc), eating jetlag (EJL), and eating window (EW) with GPA, ZSDSI, and FA. At the same time, the frequency of night eating (NE) is linearly associated with the studied parameters. NE is the strongest predictor of ZSDSI (β = 0.24), FA (β = 0.04), and GPA (β = -0.22). EPFc, EJL, and EW practically do not differ in the strength of their association with the studied indicators. ZSDSI is most closely associated with the chrononutrition indices. There is a weak negative association between BMI and EW (β = -0.03) and NE (β = -0.04). Thus, circadian eating disorders are more often observed in adolescents with poor academic performance, high levels of depression, and food addiction.

Sleep Variability, Eating Timing Variability, and Carotid Intima-Media Thickness in Early Adulthood

Background Day-to-day variability in sleep patterns and eating timing may disrupt circadian rhythms and has been linked with various adverse cardiometabolic outcomes. However, the extent to which variability in sleep patterns and eating timing relate to atherosclerotic development in subclinical stages remains unclear. Methods and Results Generally healthy adults (N=62, 29.3±7.3 years, 66% female) completed 14 days of sleep and dietary assessments via wrist accelerometry and photo-assisted diet records, respectively. Variability in sleep duration, sleep onset, eating onset (time of first caloric consumption), eating offset (time of last caloric consumption), and caloric midpoint (time at which 50% of total daily calories are consumed) were operationalized as the SD across 14 days for each variable. Separate regression models evaluated the cross-sectional associations between sleep and eating variability metrics with end-diastolic carotid intima-media thickness (CIMT) measured via ultrasonography. Models adjusted for age, sex, systolic blood pressure, sleep duration, and total energy intake. Each 60-minute increase in sleep duration SD and sleep onset SD were associated with a 0.049±0.016 mm (P=0.003) and 0.048±0.017 mm (P=0.007) greater CIMT, respectively. Variability in eating onset and offset were not associated with CIMT; however, each 60-minute increase in caloric midpoint SD was associated with a 0.033±0.015 mm greater CIMT (P=0.029). Exploratory post hoc analyses suggested that sleep duration SD and sleep onset SD were stronger correlates of CIMT than caloric midpoint SD. Conclusions Variability in sleep patterns and eating timing are positively associated with clinically relevant increases in CIMT, a biomarker of subclinical atherosclerosis, in early adulthood.

Association of Eating Pattern, Chronotype, and Social Jetlag: A Cross-Sectional Study Using Data Accumulated in a Japanese Food-Logging Mobile Health Application

Chronotype (morningness-eveningness) and social jetlag (SJL; discrepancy in the sleep pattern between the weekday and weekend) are related to eating behavior and health. The association between sleep behavior and the daily macro- and micronutrient eating pattern of each meal (breakfast, lunch, and dinner) have not been discussed well and need more evidence. Here, meal pattern datasets of Japanese participants aged 20-59 years were obtained as averages over 1 month from the data stored in the food-logging app "Asken". We allocated three groups for each chronotype and SJL. Multiple regression analyses revealed that morning chronotype and small SJL were associated with higher total daily intake of potassium, fiber, magnesium, phosphorus, and vitamin K. Breakfast energy intake and consumption of nutrients, including protein, lipid, carbohydrate, and minerals, were higher in the morning chronotype or small SJL. Lunch intake of potassium, cholesterol, fiber, magnesium, and vitamin K was also higher in the morning chronotype or small SJL. Dinner energy intake and nutrient intake of proteins, lipids, carbohydrates, sodium, and saturated fatty acids were lower in the morning chronotype or small SJL. The current data would help to establish a detailed reference for dietary intake which considers eating patterns over a day.

Weight status of working adults: The effects of eating misalignment, chronotype, and eating jetlag during mandatory confinement

This study aimed to examine the association between chronotype, eating jetlag, and eating misalignment with weight status among Malaysian adults during the COVID-19 restriction. This online cross-sectional study included 175 working adults recruited from March to July 2020. The chronotype was assessed using Morningness Eveningness Questionnaire (MEQ) while eating jetlag and mealtime variability were measured using Chrononutrition Profile Questionnaire (CPQ). Multiple linear regression demonstrated that lower breakfast frequency (β=-0.258, p = .002) and longer eating duration (β = 0.393, p < .001) were associated with later first eating events on workfree days. Both intermediate (β = 0.543, p < .001) and evening chronotypes (β = 0.523, p = .001) tend to eat their first meals later compared to morning person. Similar patterns were observed for overall eating jetlaggers in which lower breakfast frequency (β=-0.022, p = .011), longer eating duration (β = 0.293, p < .001), intermediate chronotype (β = 0.512, p < .001), and evening chronotype (β = 0.495, p = .003) were associated with eating later meals on workfree days. Additionally, higher BMI was also associated with eating later meals on workfree days (β = 0.181, p = .025). During movement restriction, discrepancies of mealtimes during work and workfree days offer new insight into modern eating habits that can influence weight status and general eating habits such as breakfast skipping and total daily eating duration. Population meal timing variability was affected during movement restrictions, and it was closely related to weight status.

Time-restricted eating improves measures of daily glycaemic control in people with type 2 diabetes

AIMS

Examine the effect of 5 d/wk, 9-h time-restricted eating (TRE) protocol on 24-h glycaemic control in adults with type 2 diabetes (T2D).

METHODS

Nineteen adults with T2D (10 F/9 M; 50 ± 9 y, HbA1c 7.6% (60 mmol/mol), BMI ∼34 kg/m²) completed a pre-post non-randomised trial comprising of a 2-wk Habitual monitoring period followed by 9-h (10:00-19:00 h) TRE for 4-wk. Glycaemic control was assessed via continuous glucose monitoring (CGM; for mean 24-h glucose concentrations, 24-h total area under the curve (AUC) and glucose variability metrics), with dietary records and physical activity monitoring. Changes in CGM measures, dietary intake and physical activity were assessed with linear mixed-effects models.

RESULTS

TRE did not alter dietary energy intake, macronutrient composition or physical activity, but reduced the daily eating window (-2 h 35 min, P < 0.001). Compared to the Habitual period, 24-h glucose concentrations (mean, SD) and AUC decreased in the 4-wk TRE period (mean: -0.7 ± 1.2 mmol/L, P = 0.02; SD: -0.2 ± 0.3 mmol/L, P = 0.01; 24-h AUC: -0.9 ± 1.4 mmol/L⋅h^-1 P = 0.01). During TRE, participants spent 10% more time in range (3.9-10.0 mmol/L; P = 0.02) and 10% less time above range (>10.0 mmol/L; P = 0.02).

CONCLUSIONS

Adhering 5 d/wk. to 9-h TRE improved glycaemic control in adults with T2D, independent of changes in physical activity or dietary intake.

CLINICAL TRIAL REGISTRATION

Australia New Zealand Clinical Trial Registry, ACTRN12618000938202.

Variable Eating Patterns: A Potential Novel Risk Factor for Systemic Inflammation in Women

BACKGROUND

The timing and regularity of eating patterns could play a role in systemic inflammation, as circadian clocks responsible for daily rhythms of inflammatory signaling are entrained by food intake.

PURPOSE

To evaluate associations of intra-weekly and weekday-weekend differences in eating timing patterns with high-sensitivity C-reactive protein (hsCRP).

METHODS

A community-based sample of 103 U.S. women from the American Heart Association Go Red for Women Strategically Focused Research Network completed a meal-timing questionnaire and provided a blood sample for measurement of hsCRP. Differences in weekday versus weekend eating start time, eating end time, and nightly fasting duration were calculated as eating jetlag metrics. Intra-weekly variability in eating timing patterns was defined by the standard deviation (SD) of these variables. Multivariable linear regression models were used to evaluate cross-sectional associations of eating timing variability metrics with hsCRP.

RESULTS

Each additional 30-min difference in weekday-weekend eating end time was related to 13% higher hsCRP (p = .023). Similarly, every 30-min increase in eating end time SD, reflecting greater variability in timing of last eating occasion, was associated with 29% higher hsCRP. Per 1-hr weekday-weekend difference in nightly fasting duration, there was a 45% elevation in hsCRP (p = .003). Every 30-min increase in nightly fasting duration SD, representing greater variability in span of the daily fasting/eating periods, was associated with 46% higher hsCRP.

CONCLUSIONS

Variable eating timing patterns were associated with higher hsCRP. Intervention studies are needed to determine whether stabilizing the timing of eating occasions may represent a novel strategy to reduce chronic inflammation.

Associations of chronotype and social jetlag with eating jetlag and their changes among German students during the first COVID-19 lockdown. The Chronotype and Nutrition study

Due to their biologically later chronotype, young students are vulnerable to a discrepant sleeping pattern between work- and free days, coined social jetlag (SJL). This study examined whether a later chronotype and/or a larger SJL are related to an analogous discrepancy in meal timing defined as eating jetlag (EJL) and whether chronotype and/or changes in SJL during the first COVID-19 related lockdown in Germany associated with changes in EJL. Baseline data were collected from September 2019-January 2020 among 317 students (58% females) aged 18-25 years of which a total of 156 students (67% females) completed an online follow-up survey in June-July 2020 (1st lockdown). Data were collected on daily routines, timing of meals/snacks, and physical activity. Chronotype was determined using the Munich ChronoType Questionnaire; SJL and EJL correspond to the difference in the daily midpoint of sleep/eating duration between work- and free days. Multivariable linear regression revealed that students with a later chronotype or a larger SJL experienced a larger EJL (p_adjusted = 0.0124 and p_adjusted<0.0001). A later chronotype at baseline and reductions in SJL during lockdown associated with concurrent reductions in EJL (p_adjusted = 0.027 and p_adjusted<0.0001). In conclusion, students with a later chronotype exhibit a more erratic meal pattern, which associates with SJL. During lockdown, flexible daily schedules allowed students to align the meal timing with their inner clock.

Multidimensional self-rating biological rhythm disorder and its association with depression and anxiety symptoms among adolescents aged 11-23 years: a school-based cross-sectional study from China

BACKGROUND

Depression and anxiety are topical concerns worldwide, especially among adolescents. Besides, biological rhythm disorder as a candidate mechanism for mood disorders is highly prevalent, but relevant research among adolescents in China is presently limited. We conducted the present study to investigate the distribution of multi-dimensional self-rating biological rhythm disorder and the association of self-rating biological rhythm disorders with depression and anxiety symptoms among Chinese adolescents in different academic stages.

METHODS

In the cross-sectional study, 3693 students aged 11-23 from Zhengzhou City, Henan Province, China were included. The Patient Health Questionnaire (PHQ-9) and General Anxiety Disorder (GAD-7) were used to evaluate symptoms of depression and anxiety, respectively. Additionally, the Self-Rating of Biological Rhythm Disorder for Adolescents (SBRDA) was used to assess status of biological rhythm disorders. Multivariate logistic regression was developed to explore factors potentially associated with symptoms of depression and anxiety stratified by academic stages.

RESULTS

Among all participants, 44.14 and 36.15% suffered from depression and anxiety symptoms, respectively. On average, participants scored 74.66 ± 19.37 on the measure of total biological rhythm disorder. Adjusted for demographic confounding factors, the logistic regression analysis showed higher scores of total biological rhythm disorder were associated with more severe depression (OR = 14.38, 95%CI: 11.38-18.16) and anxiety symptoms (OR = 11.63, 95%CI: 9.14-14.81). The similar results were also found in the stratified analysis by academic stages.

CONCLUSIONS

Self-rating biological rhythm disorders are significantly associated with depression and anxiety symptoms among adolescents. Discrepancy across academic stages should also be taken into account in establishing public health strategies.

Wearable Cameras Reveal Large Intra-Individual Variability in Timing of Eating among Young Adults

Studies have shown that young adults follow less structured eating patterns compared with older cohorts. This may have implications for dietary assessment methods which rely on memory and structured meal patterns. Our aim was to describe the intra-individual variation of eating times in young adults aged 18−30 years. Participants (n = 41) wore an Autographer camera that captured first-person perspective images every 30 s for three consecutive days. All images were timestamped and those showing food consumption were used to extract data such as the timing of the first and last eating occasions (EOs), number of EOs per day, and length of eating window. Intra-individual variability was calculated from these data using composite phase deviation (CPD) and coefficient of variation (CV). The number of individuals with high or very high variability was 28 and 18 for timing of first and last EOs, respectively (CPD > 1.70), and 27 and 17 for number of EOs and eating window, respectively (CV > 20%). In this sample of young adults, the lack of regularity in eating patterns should be considered when selecting a dietary assessment method.

Circadian clocks of the kidney: function, mechanism, and regulation

An intrinsic cellular circadian clock is located in nearly every cell of the body. The peripheral circadian clocks within the cells of the kidney contribute to the regulation of a variety of renal processes. In this review, we summarize what is currently known regarding the function, mechanism, and regulation of kidney clocks. Additionally, the effect of extrarenal physiological processes, such as endocrine and neuronal signals, on kidney function is also reviewed. Circadian rhythms in renal function are an integral part of kidney physiology, underscoring the importance of considering time of day as a key biological variable. The field of circadian renal physiology is of tremendous relevance, but with limited physiological and mechanistic information on the kidney clocks this is an area in need of extensive investigation.

Early Childhood Diet in Relation to Toddler Nighttime Sleep Duration Trajectories

The objective of this study was to evaluate whether dietary habits at age 2 associate with sleep duration trajectories through age 5 in children from north and central Appalachia. A total of 559 children from the Center for Oral Health Research in Appalachia (COHRA) cohort 2 were followed via caregiver phone interviews up to six times between ages 2 and 5. Exposures included data from the year 2 interview: sleep habits, household and demographic characteristics, meal patterns and consumption frequencies of fruits, vegetables, water, juice, milk, and soda. Sleep duration trajectories were identified using group-based trajectory models from ages 2 to 5. Three distinct nightly sleep duration trajectories were identified: short, increasing duration (4.5% of the study population); steady, 9 h of sleep (37.3%); and longer, slightly decreasing sleep duration (58.2%). Using multinomial logistic models that accounted for confounders, children with consistent meal patterns (i.e., meals and snacks at same time every day) and with higher fruit and vegetable consumption were more likely to follow the longer duration sleep trajectory compared to the steady sleep trajectory. In contrast, children who drank milk more frequently at age 2 were less likely to be in the longer duration sleep trajectory than the steady sleep trajectory.

A Time to Rest, a Time to Dine: Sleep, Time-Restricted Eating, and Cardiometabolic Health

Cardiovascular disease (CVD) poses a serious health and economic burden worldwide. Modifiable lifestyle factors are a focus of research into reducing the burden of CVD, with diet as one of the most investigated factors. Specifically, the timing and regularity of food intake is an emerging research area, with approaches such as time-restricted eating (TRE) receiving much attention. TRE involves shortening the time available to eat across the day and is associated with improved CVD outcomes compared with longer eating windows. However, studies that have examined TRE have not considered the impact of sleep on CVD outcomes despite recent evidence showing that sleep duration can influence the timing and amount of food eaten. In this article, we argue that as TRE and sleep influence each other, and influence the same cardiometabolic parameters, experiencing inadequate sleep may attenuate any positive impact TRE has on CVD. We examine the relationship between TRE and CVD, with sleep as a potential mediator in this relationship, and propose a research agenda to investigate this relationship. This will provide necessary evidence to inform future interventions aimed at reducing the burden of CVD.

Life before and after COVID-19: The 'New Normal' Benefits the Regularity of Daily Sleep and Eating Routines among College Students

After the COVID-19 lockdown, a 'new normal' was established, involving a hybrid lifestyle that combined face-to-face with virtual activity. We investigated, in a case-control study, the impact of the 'new normal' on daily sleep and eating routines, compared with pre-pandemic conditions. To do this, we propose using social and eating jet lag as markers of the regularity in daily routines. Additionally, we studied whether the 'new normal' had an impact on the body mass index (BMI), diet quality, and other health-related variables. This study included 71 subjects in the pre-pandemic group, and 68 in the 'new normal' group (20-30 years). For all participants, we evaluated social and eating jet lag, BMI, diet and sleep quality, eating behaviors, physical activity, and well-being. General linear models were used to compare outcome variables between pre-pandemic and 'new normal' groups. The results revealed that the 'new normal' was associated with greater regularity in daily sleep and eating routines (-0.7 h of social jet lag (95% CI: -1.0, -0.4), and -0.3 h of eating jet lag (95% CI: -0.5, -0.1)), longer sleep duration on weekdays (1.8 h (95% CI: 1.5, 2.2)), and lower sleep debt (-1.3 h (95% CI: -1.7, -0.9)). Regarding BMI and other health-related variables, we observed that these variables were similar between 'new normal' and pre-pandemic groups. These findings indicate that the 'new normal' had a positive impact on daily sleep and eating routines. Additionally, our results indicated that the 'new normal' offered college students a more sustainable lifestyle, which was associated with more hours of sleep during the week and lower sleep debt. This, in the long run, could have a positive impact on BMI and overall health.