Timing of food intake is an emerging aspect of nutrition; however, there is a lack of research accurately assessing food timing in the context of the circadian system. The study aimed to investigate the relation between food timing relative to clock time and endogenous circadian timing with adiposity and further explore sex differences in these associations among 151 young adults aged 18–25 years. Participants wore wrist actigraphy and documented sleep and food schedules in real time for 7 consecutive days. Circadian timing was determined by dim-light melatonin onset (DLMO). The duration between last eating occasion and DLMO (last EO-DLMO) was used to calculate the circadian timing of food intake. Adiposity was assessed using bioelectrical impedance analysis. Of the 151 participants, 133 were included in the statistical analysis finally. The results demonstrated that associations of adiposity with food timing relative to circadian timing rather than clock time among young adults living in real-world settings. Sex-stratified analyses revealed that associations between last EO-DLMO and adiposity were significant in females but not males. For females, each hour increase in last EO-DLMO was associated with higher BMI by 0·51 kg/m2 (P = 0·01), higher percent body fat by 1·05 % (P = 0·007), higher fat mass by 0·99 kg (P = 0·01) and higher visceral fat area by 4·75 cm2 (P = 0·02), whereas non-significant associations were present among males. The findings highlight the importance of considering the timing of food intake relative to endogenous circadian timing instead of only as clock time.

Later timing of eating has been associated with higher adiposity among adults and children in several studies, but not all. Moreover, studies in younger children are scarce. Hence, this study investigated the associations of the timing of evening eating with BMI Z-score and waist-to-height ratio (WHtR), and whether these associations were moderated by chronotype among 627 preschoolers (3–6-year-olds) from the cross-sectional DAGIS survey in Finland. Food intake was measured with 3-d food records, and sleep was measured with hip-worn actigraphy. Three variables were formed to describe the timing of evening eating: (1) clock time of the last eating occasion (EO); (2) time between the last EO and sleep onset; and (3) percentage of total daily energy intake (%TDEI) consumed 2 h before sleep onset or later. Chronotype was assessed as a sleep debt-corrected midpoint of sleep on the weekend (actigraphy data). The data were analysed with adjusted linear mixed effects models. After adjusting for several confounders, the last EO occurring closer to sleep onset (estimate = −0·006, 95 % CI (−0·010, −0·001)) and higher %TDEI consumed before sleep onset (estimate = 0·0004, 95 % CI (0·00003, 0·0007)) were associated with higher WHtR. No associations with BMI Z-score were found after adjustments. Clock time of the last EO was not significantly associated with the outcomes, and no interactions with chronotype emerged. The results highlight the importance of studying the timing of eating relative to sleep timing instead of only as clock time.

This study examined differences in food groups consumed at eating occasions by the level of adherence to dietary guidelines in Australian adults (≤19 years) and whether consumption differed with respect to age, sex and education levels. Secondary analysis of the 2011–2012 National Nutrition and Physical Activity Survey (n 9054) was performed, using one 24-h dietary recall with self-reported eating occasions. Dietary Guideline Index scores were used to assess adherence to the 2013 Australian Dietary Guidelines. Mean differences (95 % CI) in servings of the five food groups and discretionary foods at eating occasions were estimated for adults with higher and lower diet quality, stratified by sex, age group and education. Using survey-based t-tests, differences of at least half a serving with P values < 0·05 were considered meaningful. Compared with adults with lower diet quality, women and men aged 19–50 years with higher diet quality consumed more serves of vegetables at dinner (mean difference (95 % CI), women; 1·0; 95 % CI (0·7, 1·2); men: 0·9; 95 % CI (0·6, 1·3)) and fewer serves of discretionary foods at snacks (women: −0·7; 95 % CI (−0·9, −0·5); men: −1·0; 95 % CI (−1·4, −0·7). Other food groups, such as grains, dairy products and alternatives, meats and alternatives, were not significantly different between adults with lower and higher diet quality, across any eating occasions and age groups. Discretionary food intake at lunch, dinner and snacks was consistently greater among adults with lower diet quality, regardless of education level. Our findings identify dinner and snacks as opportunities to increase vegetable intake and reduce discretionary food intake, respectively.

This paper investigates the prevalence and interaction of overweight/obesity-related lifestyles (specifically, examining whether subjects meet the recommended criteria), in a representative sample of university students. This study is part of the project EHU12/24, an observational cross-sectional study, designed to assess the prevalence of excess body fat (BF) and major risk of developing overweight/obesity, according to a standardised protocol. In a cohort of 603 students, aged between 18 and 28 years, of the University of the Basque Country, information about meal patterns, diet quality, physical activity, sitting time, sleeping time, toxic habits and anthropometric measurements were collected. Sampling took place from February 2014 to May 2017. Binary logistic regression models adjusted for the covariates were utilised to test the association between lifestyles and risk of excess adiposity. The prevalence of overweight/obesity, according to BF percentage, was 14·4 %. The variables analysed related to meal pattern were associated with diet quality, and less healthy food habits were associated with other less health-related behaviours. Among men, moderate/low physical activity, breakfast skipping, non-adequate breakfast duration, number of eating occasions and eating breakfast alone/depending on the occasion were associated with excess BF, while among women, low MedDietScore, moderate/high alcohol consumption, non-adequate sleep duration, eating breakfast and lunch alone/depending on the occasion. Results suggest that certain unhealthy lifestyle behaviours coexist, interact with one another and increase the risk of overweight/obesity in this population. Sex-specific differences in risk factors of obesity have implications for interventions for primary prevention of obesity within this environment.

Children’s vegetable consumption is generally below national recommendations in the UK. This study examined predictors of vegetable intake by children aged 1·5–18 years using counts and portion sizes derived from 4-d UK National Diet and Nutrition Survey food diaries. Data from 6548 children were examined using linear and logit multilevel models. Specifically, we examined whether demographic variables predicted vegetable consumption, whether environmental context influenced portion sizes of vegetables consumed and which food groups predicted the presence (or absence) of vegetables at an eating occasion (EO). Larger average daily intake of vegetables (g) was predicted by age, ethnicity, equivalised income, variety of vegetables eaten and average energy intake per d (R2 0·549). At a single EO, vegetables were consumed in larger portion sizes at home, with family members and at evening mealtimes (Conditional R2 0·308). Within EO, certain configurations of food groups such as carbohydrates and protein predicted higher odds of vegetables being present (OR 12·85, 95 % CI 9·42, 17·54), whereas foods high in fats, sugars and salt predicted a lower likelihood of vegetable presence (OR 0·03, 95 % CI 0·02, 0·04). Vegetables were rarely eaten alone without other food groups. These findings demonstrate that only one portion of vegetables was eaten per d (median) and this was consumed at a single EO, therefore falling below recommendations. Future research should investigate ways to encourage vegetable intake at times when vegetables are not regularly eaten, such as for breakfast and as snacks, whilst considering which other, potentially competing, foods are presented alongside vegetables.