Chronotype

BackgroundA later chronotype has been found to be associated with unhealthy habits and diseases, such as an unhealthy diet and metabolic syndrome in adults. Little is known about the association between chronotype, eating habits, physical activity and obesity. Thus, this study aimed to explore the relationships between chronotype, eating behaviors, physical activity, and overweight in Chinese school-aged children.MethodsData from this study was based on 952 schoolchildren (10-12 y) from six primary schools that participated in China. Anthropometric measurements of height and body weight were performed. Information about sleeping habits, dietary behaviors, and other lifestyle behaviors was gathered using a self-administered questionnaire. Multiple linear regression analysis or multivariable logistic regression model was performed to assess the associations between chronotype, eating behaviors, physical activity, and overweight.ResultsNearly 70% (69.9%) of the participants had a self-reported morning chronotype. Multiple linear regression analysis revealed chronotype score was positively associated with physical activities (all P values ConclusionsThis study indicates that early chronotype children are more active, have healthier dietary habits, get more sleep, have shorter social jet lag, and are less likely to be overweight than non-early chronotype children. Our findings suggest that later chronotype may be a potential indicator in the early detection of overweight, unhealthy eating, and physical inactivity behaviors. Chronotype has been found to have an important impact on individual's health. In the present study, we conducted a cross-sectional study to investigate the association between chronotype, eating behaviors, physical activity, and overweight in school-aged children. The findings showed that children with early chronotype is associated with more active, healthier dietary behaviors, longer sleep duration, short social jet lag, and a lower risk of overweight.

Purpose of reviewThis review primarily provides an overview of the current evidence on chronotype (which reflects an individual's preference for the timing of sleeping, eating, and activity in a 24-h period) and sleep quality changes in obesity in postmenopausal women. It also explores possible nutritional strategies to manage these changes in this phase of a woman's life.Recent findingsMenopause is a life stage frequently associated with sleep disturbances and changes in circadian rhythms. Sleep disturbances are one of the main symptoms of menopause and are caused by several factors such as hormonal changes, obesity, and melatonin reduction. In addition, the chronotype also changes following menopause. Nutritional strategies are essential because they could help manage menopausal sleep disturbances and circadian misalignment, particularly by tackling obesity and overweight. In the management of postmenopausal women, especially those experiencing obesity, careful assessment of sleep disturbances and chronotype and subsequent development of the most appropriate treatment, including nutritional management, should be part of the treatment routine.

AimsThe aim of the study was to evaluate the association between evening chronotype and social jetlag (SJL) with obesity, blood glucose and lipid levels in non-shift working adults.MethodsThe databases of MEDLINE, EMBASE and Cochrane Reviews were searched for studies analyzing the metabolic parameters among groups of different chronotypes or SJL until Feb 2022. Weighted mean difference (WMD) and 95% confidence intervals (CI) were used to analyze the association between these parameters and chronotypes or SJL.ResultsA total of 27 studies were included in this meta-analysis. Compared with morning chronotype, the participants with evening chronotype had higher body mass index (BMI) (WMD= 0.44 kg/m2, 95%CI, 0.30 to 0.57 kg/m2, pConclusionsEvening chronotype and SJL were associated with obesity and unfavorable metabolic parameters of glucose and lipid metabolism.Systematic review registrationhttps://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022303401.

PURPOSE OF REVIEW: This review explores the integration of chronobiology and chronotype-specific factors into the Mediterranean Diet (MD) framework. While the MD is widely recognized for its cardiometabolic and neuroprotective effects, current guidelines do not address the timing of food intake or the influence of individual chronotype. Given the growing evidence linking circadian alignment, meal timing, and metabolic health, we propose a revised Mediterranean Diet pyramid tailored to chronotype and lifestyle determinants, herein referred to as the chronotype-based Mediterranean Diet Pyramid of the Italian Society of Endocrinology (SIE) and the Italian Society of Dietetics and Clinical Nutrition (ADI). RECENT FINDINGS: Chrononutrition emphasizes the timing, frequency, and regularity of meals as key elements for metabolic regulation. Early-day energy intake, time-restricted eating, and alignment with circadian rhythms improve glycemic control, weight management, and cardiovascular outcomes. Morning chronotypes tend to show higher adherence to the MD, whereas evening chronotypes more frequently delay meals, skip breakfast, and consume energy-dense foods at night, contributing to poorer metabolic profiles. Sleep duration and quality further modulate appetite regulation and dietary adherence. Building on these insights, the proposed pyramid integrates circadian cues, represented by sun and moon symbols, to guide nutrient timing. Foods rich in carbohydrates and fiber (whole grains, legumes, fruits) are emphasized earlier in the day, while protein- and vegetable-based meals are prioritized in the evening, alongside sleep-promoting foods such as dairy, nuts, and seeds. Lifestyle pillars, including physical activity, adequate sleep, and the alignment of eating schedules with chronotype, form the foundation of the pyramid. The integration of chronobiological principles into the MD offers a novel paradigm that couples dietary quality with circadian alignment. A chronotype-oriented MD pyramid may enhance adherence, optimize metabolic flexibility, and reinforce the MD as a holistic model encompassing nutrition, lifestyle, and sustainability.