This study aimed to investigate the relationship between meal frequency and obesity in Chinese adults aged 18 to 59 years. The data came from the 2015 Chinese Adult Chronic Disease and Nutrition Surveillance (CACDNS 2015) and provincial dietary environment data from the 2015 National Statistical Yearbook. A total of 34,206 adults aged 18 to 59 who took part in the diet survey were selected as the study participants. A two-level multivariate logistic regression model was used to adjust for the socioeconomic and nutritional status of individuals. For parameter estimation, a numerical integral approach was used to analyze the relationship between meal frequency (including meals at home, the workplace or school dining halls, and eating away from home) and obesity. A two-level “provincial–individual” logistic multivariate regression analysis was performed with obesity as the dependent variable. The two-level multivariate analysis of variance model fitting results showed that after adjusting for the effects of gender, age, occupation, education, marital status, family per capita annual income, provincial gross domestic product (GDP), restaurant industry turnover, consumer price index of EAFH food, and energy intake, the frequency of eating at home was not associated with obesity (all p > 0.05); the frequency of eating at dining halls ≥1 to <2 times per day (OR = 0.784, p = 0.0122) showed a negative association with obesity; the frequency of eating away from home < 1 times per day and ≥1 to <2 times per day were positively correlated with obesity (<1 time per day: OR = 1.123, p = 0.0419; ≥1 to <2 times per day: OR = 1.249, p = 0.0022). The results of the two-level random-intercept logistic multivariate mixed-effects prediction model for obesity in adults aged 18 to 59 years showed that no statistical association was noticed between the frequency of eating at home and obesity in adults aged 18 to 59 years. However, adults who ate out < 1 time and ≥1 to <2 times a day showed higher risks of obesity than those who did not eat out, with OR = 1.131 (95% CI 1.012–1.264) and OR = 1.258 (95% CI 1.099–1.440), while adults who ate at school and workplace dining halls ≥1 to <2 times a day may have a reduced risk of obesity, with OR = 0.790 (95% CI 0.656–0.951). This result could not be found based on the definition of eating out in previous studies. Therefore, it is recommended to exclude nonprofit collective canteens such as school and workplace dining halls from the definition of eating away from home, and to redefine eating out in terms of health effects. At the same time, it is also recommended to strengthen collective nutritional interventions around canteens, improve the nutritious meal system in school and workplace canteens, and create healthy canteens. Full article

We aim to describe temporal eating patterns in a population of adults with overweight or obesity. In this cross-sectional analysis, data were combined from two separate pilot studies during which participants entered the timing of all eating occasions (>0 kcals) for 10–14 days. Data were aggregated to determine total eating occasions, local time of the first and last eating occasions, eating window, eating midpoint, and within-person variability of eating patterns. Eating patterns were compared between sexes, as well as between weekday and weekends. Participants (n = 85) had a median age of 56 ± 19 years, were mostly female (>70%), white (56.5%), and had a BMI of 31.8 ± 8.0 kg/m². The median eating window was 14 h 04 min [12 h 57 min–15 h 21 min], which was significantly shorter on the weekend compared to weekdays (p < 0.0001). Only 13.1% of participants had an eating window <12 h/d. Additionally, there was greater irregularity with the first eating occasion during the week when compared to the weekend (p = 0.0002). In conclusion, adults with overweight or obesity have prolonged eating windows (>14 h/d). Future trials should examine the contribution of a prolonged eating window on adiposity independent of energy intake. Full article

Unusual meal timing has been associated with a higher prevalence of chronic disease. Those at greater risk include shift workers and evening chronotypes. This study aimed to validate the content of a Chrononutrition Questionnaire for shift and non-shift workers to identify temporal patterns of eating in relation to chronotype. Content validity was determined using a Delphi study of three rounds. Experts rated the relevance of, and provided feedback on, 46 items across seven outcomes: meal regularity, times of first eating occasion, last eating occasion, largest meal, main meals/snacks, wake, and sleep, which were edited in response. Items with greater than 70% consensus of relevance were accepted. Rounds one, two, and three had 28, 26, and 24 experts, respectively. Across three rounds, no outcomes were irrelevant, but seven were merged into three for ease of usage, and two sections were added for experts to rate and comment on. In the final round, all but one of 29 items achieved greater than 70% consensus of relevance with no further changes. The Chrononutrition Questionnaire was deemed relevant to experts in circadian biology and chrononutrition, and could represent a convenient tool to assess temporal patterns of eating in relation to chronotype in future studies. Full article