Chronotype: Implications for Epidemiologic Studies on Chrono-Nutrition and Cardiometabolic Health

In the paper

“In epidemiology, such research is currently hindered by the fact that few cross-sectional surveys or longitudinal cohorts assess chronotype or use dietary assessment methods that permit assessment of the timing of dietary intake.”

In the paper

“There was a gap in the research concerning the association between chronotype and the 3 dimensions of chrono-nutrition.”

In the paper

“Limited research was found on the association between chronotype and dietary intake in infants, children, and older adults.”

In the paper

“To date, few studies have investigated how an individual's circadian typology, i.e., one's chronotype, affects the association between chrono-nutrition and cardiometabolic health.”

In the paper

“To our knowledge, such correlations have as yet not been investigated in larger samples of the population (26).”

What the sources say

• Not checked yetcites [26] Kantermann, 2015, Comparing the Morningness-Eveningness Questionnaire and Munich ChronoType Questionnaire to the Dim Light Melatonin Onset, J Biol Rhythms source

In the paper

“Other variations of the MEQ have been proposed but remain to be validated in large-scale studies (35).”

What the sources say

• Not checked yetcites [35] Turco, 2015, The self-morningness/eveningness (Self-ME): an extremely concise and totally subjective assessment of diurnal preference, Chronobiol Int source

In the paper

“Accordingly, country-specific differences in chronotype have been reported by several studies (46, 56–58).”

What the sources say

• Not checked yetcites [46] Malone, 2016, Ethnic differences in sleep duration and morning-evening type in a population sample, Chronobiol Int source
• Not checked yetcites [56] Randler, 2008, Morningness-eveningness comparison in adolescents from different countries around the world, Chronobiol Int source
• Not checked yetcites [57] Randler, 2015, Cross-cultural comparison of seven morningness and sleep-wake measures from Germany, India and Slovakia, Int J Psychol source
• Not checked yetcites [58] Horzum, 2015, Morningness–eveningness and the environment hypothesis – a cross-cultural comparison of Turkish and German adolescents, Chronobiol Int source

In the paper

“These findings have been replicated in other populations and countries (68, 69).”

What the sources say

• Not checked yetcites [68] Yadav, 2014, Relationship of chronotype to sleep pattern in a cohort of college students during work days and vacation days, Indian J Exp Biol
• Not checked yetcites [69] Kabrita, 2014, Predictors of poor sleep quality among Lebanese university students: association between evening typology, lifestyle behaviors, and sleep habits, Nat Sci Sleep source

In the paper

“To date, there are limited studies that have investigated the association between chronotype and diet in infants and young children.”

In the paper

“The few studies that have investigated chronotype in young children, through the use of the Children's Chronotype Questionnaire or DLMO, all have repeatedly observed a greater prevalence of morning chronotype in young children (5, 94, 95).”

What the sources say

• Not checked yetcites [5] Roenneberg, 2004, A marker for the end of adolescence, Curr Biol source
• Not checked yetcites [94] Simpkin, 2014, Chronotype is associated with the timing of the circadian clock and sleep in toddlers, J Sleep Res source
• Not checked yetcites [95] Werner, 2009, Assessment of chronotype in four- to eleven-year-old children: reliability and validity of the Children's Chronotype Questionnaire (CCTQ), Chronobiol Int source

In the paper

“It is not clear based on the currently available literature whether or not chronotype is a determinant (causal factor) of eating patterns or food intake or merely a reflection of a complex set of behaviors that also affect diet (associated to diet owing to confounding factors).”

In the paper

“The resulting misalignment between the sleep-awake, fasting-feeding cycles, and the light-dark cycle subsequently disrupts the natural oscillations of physiologic processes such as glucose, lipid metabolism, and blood pressure, eventually manifesting itself as heightened risk of developing type 2 diabetes and cardiovascular disease (1–4).”

What the sources say

• Not checked yetcites [1] Almoosawi, 2016, Chrono-nutrition: a review of current evidence from observational studies on global trends in time-of-day of energy intake and its association with obesity, Proc Nutr Soc source
• Not checked yetcites [2] Johnston, 2016, Circadian rhythms, metabolism, and chrononutrition in rodents and humans, Adv Nutr source
• Not checked yetcites [3] Bedrosian, 2016, Endocrine effects of circadian disruption, Annu Rev Physiol source
• Not checked yetcites [4] St-Onge, 2017, Meal timing and frequency: implications for cardiovascular disease prevention: a scientific statement from the American Heart Association, Circulation source

In the paper

“Such sampling procedures may be burdensome in the context of large-scale studies, because they require a large set of resources and participant supervision (26).”

What the sources say

• Not checked yetcites [26] Kantermann, 2015, Comparing the Morningness-Eveningness Questionnaire and Munich ChronoType Questionnaire to the Dim Light Melatonin Onset, J Biol Rhythms source

In the paper

“there is evidence to suggest that the underlying distribution of chronotypes follows a normal bell shape, with tail ends reflecting extreme morning and evening chronotypes (6).”

What the sources say

• Not checked yetcites [6] Allebrandt, 2008, The search for circadian clock components in humans: new perspectives for association studies, Braz J Med Biol Res source

In the paper

“Currently, the most reliable measure of circadian phase in the human master clock is DLMO (26).”

What the sources say

• Not checked yetcites [26] Kantermann, 2015, Comparing the Morningness-Eveningness Questionnaire and Munich ChronoType Questionnaire to the Dim Light Melatonin Onset, J Biol Rhythms source

In the paper

“This, in turn, may result in a redistribution of energy and macronutrient intake towards later in the day.”

In the paper

“To this end, factors such as cost, participant burden, and misreporting continue to affect the scalability of the few epidemiologic studies that deploy traditional paper-based 24-h recalls or food records to capture the 3 time dimensions of eating (23).”

What the sources say

• Not checked yetcites [23] Amoutzopoulos, 2018, J Nutr Sci source

In the paper

“Food intake and eating patterns likewise exhibit diurnal rhythms (14, 17)”

What the sources say

• Not checked yetcites [14] Stephan, 2002, The “other” circadian system: food as a Zeitgeber, J Biol Rhythms source
• Not checked yetcites [17] Mendoza, 2007, Circadian clocks: setting time by food, J Neuroendocrinol source

In the paper

“there is emerging evidence suggesting that the timing of dietary intake, so-called chrono-nutrition, may be influenced by an individual's chronotype (18–21).”

What the sources say

• Not checked yetcites [18] Bravo, 2013, Tryptophan-enriched cereal intake improves nocturnal sleep, melatonin, serotonin, and total antioxidant capacity levels and mood in elderly humans, Age source
• Not checked yetcites [19] Meule, 2012, Skipping breakfast: morningness-eveningness preference is differentially related to state and trait food cravings, Eat Weight Disord
• Not checked yetcites [20] Randler, 2010, Morningness-eveningness, habitual sleep-wake variables and cortisol level, Biol Psychol source
• Not checked yetcites [21] Reutrakul, 2014, The relationship between breakfast skipping, chronotype, and glycemic control in type 2 diabetes, Chronobiol Int source

In the paper

“Indeed, the role of social factors as key modifiable determinants of an individual's chronotype is increasingly recognized (64, 65).”

What the sources say

• Not checked yetcites [64] Levandovski, 2011, Depression scores associate with chronotype and social jetlag in a rural population, Chronobiol Int source
• Not checked yetcites [65] Carvalho, 2014, Differences in circadian patterns between rural and urban populations: an epidemiological study in countryside, Chronobiol Int source

In the paper

“More recently, genome-wide association studies that used questionnaire-based evaluations of individual chronotypes have characterized important polymorphisms in regions containing known clock genes as well as other loci (40–43).”

What the sources say

• Not checked yetcites [40] Hu, 2016, GWAS of 89,283 individuals identifies genetic variants associated with self-reporting of being a morning person, Nat Commun source
• Not checked yetcites [41] Allebrandt, 2010, CLOCK gene variants associate with sleep duration in two independent populations, Biol Psychiatry source
• Not checked yetcites [42] Jones, 2016, Genome-wide association analyses in 128,266 individuals identifies new morningness and sleep duration loci, PLoS Genet source
• Not checked yetcites [43] Lane, 2016, Genome-wide association analysis identifies novel loci for chronotype in 100,420 individuals from the UK Biobank, Nat Commun source

In the paper

“For instance, boys whose parents did not enforce a bedtime routine during childhood were more likely to have an evening chronotype during adolescence (53).”

What the sources say

• Not checked yetcites [53] Takeuchi, 2001, Parental enforcement of bedtime during childhood modulates preference of Japanese junior high school students for eveningness chronotype, Chronobiol Int source

In the paper

“For instance, in women, but not in men, having children was found to be the strongest determinant of morningness.”

What the sources say

• Not checked yetcites [49] Leonhard, 2009, In sync with the family: children and partners influence the sleep-wake circadian rhythm and social habits of women, Chronobiol Int source

In the paper

“In relation to ethnicity, data from the UK Biobank Study have demonstrated that individuals with a British black ethnicity are 1.4 times more likely to have a morning chronotype compared with white British (46).”

What the sources say

• Not checked yetcites [46] Malone, 2016, Ethnic differences in sleep duration and morning-evening type in a population sample, Chronobiol Int source

In the paper

“One particular study found that the distribution of chronotype in urban Sao Pãulo in Brazil was similar to that in London, despite differences in latitude (61).”

What the sources say

• Not checked yetcites [61] von Schantz, 2015, Distribution and heritability of diurnal preference (chronotype) in a rural Brazilian family-based cohort, the Baependi study, Sci Rep source

In the paper

“In a cross-country comparison, Germans were found to have a greater prevalence of evening chronotype than were Indians and Slovakians (57).”

What the sources say

• Not checked yetcites [57] Randler, 2015, Cross-cultural comparison of seven morningness and sleep-wake measures from Germany, India and Slovakia, Int J Psychol source

In the paper

“individuals with a black ethnicity are more likely to undertake shift work according to some studies (46, 47).”

What the sources say

• Not checked yetcites [46] Malone, 2016, Ethnic differences in sleep duration and morning-evening type in a population sample, Chronobiol Int source
• Not checked yetcites [47] Jackson, 2014, Racial/ethnic disparities in short sleep duration by occupation: the contribution of immigrant status, Soc Sci Med source

In the paper

“In relation to older adults, disruptions in circadian biology arising from the aging process are believed to underlie the change in chronotype (54)”

What the sources say

• Not checked yetcites [54] Chen, 2016, Effects of aging on circadian patterns of gene expression in the human prefrontal cortex, Proc Natl Acad Sci USA source

In the paper

“In a comparable study, Turkish adolescents were more likely to have a morning chronotype than were German adolescents (58).”

What the sources say

• Not checked yetcites [58] Horzum, 2015, Morningness–eveningness and the environment hypothesis – a cross-cultural comparison of Turkish and German adolescents, Chronobiol Int source

In the paper

“Both genetic variations and environmental factors influence the distribution of chronotypes in a given population (24) (Figure 1).”

What the sources say

• Not checked yetcites [24] Wittmann, 2006, Social jetlag: misalignment of biological and social time, Chronobiol Int source

In the paper

“Such genetic variants may underlie some of the interindividual (44) and interethnic differences (45) in the period (or τ) of the endogenous circadian cycle that manifest themselves as differences in chronotype.”

What the sources say

• Not checked yetcites [44] Goel, 2013, Circadian rhythms, sleep deprivation, and human performance, Prog Mol Biol Transl Sci source
• Not checked yetcites [45] Smith, 2009, Racial differences in the human endogenous circadian period, PLoS One source

In the paper

“Overall, the MCTQ provides the advantage of collecting detailed information on sleep-wake behavior that allows for the assessment of phenomena such as social jet lag (difference in mid-sleep timing between school and work days and school- and work-free days) (24, 33).”

What the sources say

• Not checked yetcites [24] Wittmann, 2006, Social jetlag: misalignment of biological and social time, Chronobiol Int source
• Not checked yetcites [33] Zavada, 2005, Comparison of the Munich Chronotype Questionnaire with the Horne-Östberg's Morningness-Eveningness Score, Chronobiol Int source

In the paper

“Children who drank milk at breakfast more than once a week and who ate breakfast 4 times/wk were more likely to shift from an evening to a morning chronotype (99).”

What the sources say

• Not checked yetcites [99] Kawada, 2016, Questionnaire and intervention study on effects of drinking cows' milk at breakfast on the circadian typology and mental health of Japanese infants aged 1 - 6 years, Nat Sci

In the paper

“In another study, individuals with an evening chronotype likewise had inadequate intakes of several minerals and vitamins including calcium, magnesium, zinc, and vitamin D, riboflavin, and vitamin B-6 (82).”

What the sources say

• Not checked yetcites [82] Sato-Mito, 2011, Dietary intake is associated with human chronotype as assessed by both morningness-eveningness score and preferred midpoint of sleep in young Japanese women, Int J Food Sci Nutr source

In the paper

“Accordingly, in a sample of the general population in Switzerland and Germany, it was observed that individuals with an evening chronotype accumulate sleep debt during the work week, which they compensate for by sleeping longer on weekends (66).”

What the sources say

• Not checked yetcites [66] Roenneberg, 2003, Life between clocks: daily temporal patterns of human chronotypes, J Biol Rhythms source

In the paper

“This irregularity in timing of eating based on an individual's chronotype has also been reported in relation to timing of lunch (76, 81).”

What the sources say

• Not checked yetcites [76] Silva, 2016, Chronotype, social jetlag and sleep debt are associated with dietary intake among Brazilian undergraduate students, Chronobiol Int source
• Not checked yetcites [81] Sato-Mito, 2011, The midpoint of sleep is associated with dietary intake and dietary behavior among young Japanese women, Sleep Med source

In the paper

“Several other studies have reported cross-sectional associations between an evening chronotype and higher consumption of stimulants such as caffeine, energy drinks, sugar-sweetened beverages, and alcohol in adolescents (24) and in college or university students (49, 78, 79, 84).”

What the sources say

• Not checked yetcites [24] Wittmann, 2006, Social jetlag: misalignment of biological and social time, Chronobiol Int source
• Not checked yetcites [49] Leonhard, 2009, In sync with the family: children and partners influence the sleep-wake circadian rhythm and social habits of women, Chronobiol Int source
• Not checked yetcites [78] Tran, 2014, Daytime sleepiness, circadian preference, caffeine consumption and use of other stimulants among Thai college students, J Public Health Epidemiol source

In the paper

“Besides dietary intake, studies suggest that individuals with a morning chronotype exhibit more regular eating behavior than individuals with an evening chronotype (83, 85).”

What the sources say

• Not checked yetcites [83] Fleig, 2009, Association between chronotype and diet in adolescents based on food logs, Eat Behav source
• Not checked yetcites [85] Monk, 2004, Morningness-eveningness and lifestyle regularity, Chronobiol Int source

In the paper

“Considering that dietary habits persist from adolescence into adulthood (101), and that cardiometabolic disease risk factors are often formed in childhood and adolescence (102), understanding how chronotype influences diet quality and eating patterns in childhood and adolescence is essential in guiding the development of dietary strategies to prevent chronic disease development.”

What the sources say

• Not checked yetcites [102] Matthews, 2016, Sleep characteristics and cardiovascular risk in children and adolescents: an enumerative review, Sleep Med source

In the paper

“Considering that dietary habits persist from adolescence into adulthood (101), and that cardiometabolic disease risk factors are often formed in childhood and adolescence (102), understanding how chronotype influences diet quality and eating patterns in childhood and adolescence is essential in guiding the development of dietary strategies to prevent chronic disease development.”

What the sources say

• Not checked yetcites [101] Leech, 2014, The clustering of diet, physical activity and sedentary behavior in children and adolescents: a review, Int J Behav Nutr Phys Act source

In the paper

“However, in the latter study, the circadian typology was only assessed via a subjective questionnaire with no objective biological measures such as DLMO.”

What the sources say

• Not checked yetcites [99] Kawada, 2016, Questionnaire and intervention study on effects of drinking cows' milk at breakfast on the circadian typology and mental health of Japanese infants aged 1 - 6 years, Nat Sci

In the paper

“More recently, Diederichs et al. (100) defined the term “eveningness in energy intake” and found that it was associated with greater total energy intake over the day in the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) study and may be potentially linked to the shift in chronotype between childhood and adolescence.”

What the sources say

• Not checked yetcites [100] Diederichs, 2018, In adolescence a higher ‘eveningness in ene rgy intake' is associated with higher total daily energy intake, Appetite source

In the paper

“Strokes, for instance, follow a circadian rhythm with a major morning peak and a secondary early evening peak.”

What the sources say

• Not checked yetcites [116] Manfredini, 2005, Circadian variation in stroke onset: identical temporal pattern in ischemic and hemorrhagic events, Chronobiol Int source

In the paper

“An adverse impact of time transitions on sleep has also been reported in adolescents with an evening chronotype (115).”

What the sources say

• Not checked yetcites [115] Schneider, 2009, Daytime sleepiness during transition into daylight saving time in adolescents: are owls higher at risk?, Sleep Med source

In the paper

“It is known that cerebrovascular and cardiovascular events exhibit a bimodal pattern (116).”

What the sources say

• Not checked yetcites [116] Manfredini, 2005, Circadian variation in stroke onset: identical temporal pattern in ischemic and hemorrhagic events, Chronobiol Int source

In the paper

“This is particularly true considering that irregularity of meal patterns has been identified as a novel risk factor for cardiometabolic disorders (103).”

What the sources say

• Not checked yetcites [103] Pot, 2016, Meal irregularity and cardiometabolic consequences: results from observational and intervention studies, Proc Nutr Soc source

In the paper

“For instance, data from the German MONICA/KORA Myocardial Infarction Registry indicated that specific high-risk subgroups of the population, particularly men, experience a higher risk of acute myocardial infarction during transitions to and from daylight saving time (114).”

What the sources say

• Not checked yetcites [114] Kirchberger, 2015, Are daylight saving time transitions associated with changes in myocardial infarction incidence? Results from the German MONICA/KORA Myocardial Infarction Registry, BMC Public Health source

In the paper

“Comparable with findings in adolescents and young adults, data from the UK Biobank project demonstrate that adults with a morning chronotype consume a mean of 0.25 more servings of fruit and 0.13 more servings of vegetables/d, as assessed through the use of 24-h recalls, than do adults with an evening chronotype (75).”

What the sources say

• Not checked yetcites [75] Patterson, 2016, Smoking, screen-based sedentary behavior, and diet associated with habitual sleep duration and chronotype: data from the UK Biobank, Ann Behav Med source

In the paper

“This circadian rhythmicity of glucose metabolism arises as a consequence of changes in glucose utilization, insulin sensitivity, and insulin secretion based on the time of day (119).”

What the sources say

• Not checked yetcites [119] Van Cauter, 1997, Roles of circadian rhythmicity and sleep in human glucose regulation 1, Endocr Rev

In the paper

“Severe circadian misalignment has long been recognized to be a risk factor for the development of cardiovascular diseases (108).”

What the sources say

• Not checked yetcites [108] Baron, 2014, Circadian misalignment and health, Int Rev Psychiatry source

In the paper

“In humans, glucose tolerance generally declines over the course of the day, reaching a nadir in the evening.”

What the sources say

• Not checked yetcites [119] Van Cauter, 1997, Roles of circadian rhythmicity and sleep in human glucose regulation 1, Endocr Rev

In the paper

“More recent research findings suggest that mild circadian misalignment, experienced as minor shifts between the sleep-awake cycle in non–shift workers, is also detrimental to health (50, 113).”

What the sources say

• Not checked yetcites [50] Roenneberg, 2012, Social jetlag and obesity, Curr Biol source
• Not checked yetcites [113] Roenneberg, 2013, Light and the human circadian clock

In the paper

“These associations occurred independently of sleep duration and sufficiency (13).”

What the sources say

• Not checked yetcites [13] Merikanto, 2013, Associations of chronotype and sleep with cardiovascular diseases and type 2 diabetes, Chronobiol Int source

In the paper

“Most of this evidence is derived from studies on different models of shift work, which found that shift workers working during their circadian night are more likely to develop metabolic disturbances (109).”

What the sources say

• Not checked yetcites [109] Canuto, 2013, Metabolic syndrome and shift work: a systematic review, Sleep Med Rev source

In the paper

“By contrast, in the evening, evening types reported higher intakes of energy, sucrose, fat, and saturated fatty acids than did morning types.”

What the sources say

• Not checked yetcites [72] Mirkka, 2017, Chronotype differences in timing of energy and macronutrient intakes: a population‐based study in adults, Obesity source

In the paper

“A recent meta-analysis of 12 observational studies found that among different types of shift work, rotating shift work is associated with increased risk of type 2 diabetes (123).”

What the sources say

• Not checked yetcites [123] Gan, 2015, Shift work and diabetes mellitus: a meta-analysis of observational studies, Occup Environ Med source

In the paper

“Evening chronotype has also been related to lower HDL-cholesterol concentrations (118).”

What the sources say

• Not checked yetcites [118] Wong, 2015, Social jetlag, chronotype, and cardiometabolic risk, J Clin Endocrinol Metab source

In the paper

“a recent study in Finland investigating the relation between chronotype and chrono-nutrition found that evening types reported lower energy and macronutrient intakes in the morning compared with morning types according to data collected through the use of 48-h food recalls (72).”

What the sources say

• Not checked yetcites [72] Mirkka, 2017, Chronotype differences in timing of energy and macronutrient intakes: a population‐based study in adults, Obesity source

In the paper

“Taken together, this evidence implies that chronotype may modulate physiologic processes linked to cardiovascular health, including heart rate, blood pressure, and blood lipid concentrations.”

In the paper

“Inverse associations between later bedtime, wake time, or midpoint of sleep and time spent in moderate-to-vigorous physical activity or sedentary behavior have been noted in other studies (73, 105).”

What the sources say

• Not checked yetcites [73] Maukonen, 2016, The associations between chronotype, a healthy diet and obesity, Chronobiol Int source
• Not checked yetcites [105] Shechter, 2014, Delayed sleep timing is associated with low levels of free-living physical activity in normal sleeping adults, Sleep Med source

In the paper

“Studies were also limited by the unrepresentativeness of the samples, mainly due to the small sample size, by selection bias, and by other inherent biases of observational studies.”

In the paper

“A limited number of observational studies also demonstrate that evening chronotype is potentially related to changes in timing of food intake, irregular eating, and meal skipping, particularly breakfast skipping.”

In the paper

“A similar point emerges in epidemiologic evidence, wherein most of the evidence of the association between chronotype and diet, or chronotype and cardiometabolic health, is based on cross-sectional studies that do not permit identification of cause and effect or temporality of associations.”

In the paper

“This is not to mention the limited evidence in specific population subgroups such as infants, older adults, and those at risk of developing cardiovascular diseases or type 2 diabetes.”

In the paper

“In one particular study, circadian misalignment led some subjects to exhibit postprandial glucose responses akin to the range observed in prediabetes (111).”

What the sources say

• Not checked yetcites [111] Scheer, 2009, Adverse metabolic and cardiovascular consequences of circadian misalignment, Proc Natl Acad Sci USA source

In the paper

“More recently, variants of circadian clock genes associated with chronotype and sleep homeostasis have been linked to glucose metabolism (132), potentially pointing towards the existence of an underlying network between circadian clocks, chronotype, and glucose homeostasis.”

What the sources say

• Not checked yetcites [132] Kalsbeek, 2014, Circadian control of glucose metabolism, Mol Metab source

In the paper

“Breakfast skipping was related to higher HbA1c values, even after adjusting for age, sex, race, BMI, number of diabetes complications, insulin use, depressive symptoms, perceived sleep debt, and percentage of daily caloric intake at dinner.”

What the sources say

• Not checked yetcites [21] Reutrakul, 2014, The relationship between breakfast skipping, chronotype, and glycemic control in type 2 diabetes, Chronobiol Int source

In the paper

“Together, such findings imply that circadian misalignment may predispose individuals to the development of type 2 diabetes.”

In the paper

“A further limitation is that none of the studies cited herein assessed the context within which foods are consumed at different time points, to identify if there are associations between the socioenvironmental factors and consumption of specific nutrients at a given eating occasion.”

In the paper

“Indeed, in the FINRISK 2007 study, individuals with an evening chronotype had 2.5-fold greater odds of type 2 diabetes than individuals with a morning chronotype (13).”

What the sources say

• Not checked yetcites [13] Merikanto, 2013, Associations of chronotype and sleep with cardiovascular diseases and type 2 diabetes, Chronobiol Int source