A person’s chronotype reflects individual variability in diurnal rhythms for preferred timing of sleep and daily activities such as exercise and food intake. The aim of this review is to provide an overview of the evidence around the influence of chronotype on eating behaviour and appetite control, as well as our perspectives and suggestions for future research. Increasing evidence demonstrates that late chronotype is associated with adverse health outcomes. A late chronotype may exacerbate the influence of greater evening energy intake on overweight/obesity risk and curtail weight management efforts. Furthermore, late chronotypes tend to have worse diet quality, with greater intake of fast foods, caffeine, and alcohol and lower intake of fruits and vegetables. Late chronotype is also associated with eating behaviour traits that increase the susceptibility to overconsumption such as disinhibition, food cravings, and binge eating. Whether an individual’s chronotype influences appetite in response to food intake and exercise is an area of recent interest that has largely been overlooked. Preliminary evidence suggests additive rather than interactive effects of chronotype and meal timing on appetite and food reward, but that hunger may decrease to a greater extent in response to morning exercise in early chronotypes and in response to evening exercise in late chronotypes. More studies examining the interplay between an individual’s chronotype, food intake/exercise timing and sleep are required as this could be of importance to inform personalised dietary and exercise prescriptions to promote better appetite control and weight management outcomes.

The lifestyle of the population has undergone significant changes due to the COVID-19 pandemic, which could have influenced alterations in dietary habits and overall well-being among workers. This study aimed to evaluate healthy eating practices and their relationship with the workers’ quality of life and physical activity during the COVID-19 pandemic. This was a cross-sectional investigation involving workers in the city of Curitiba, southern Brazil. The study was conducted through the application of an online questionnaire. The data were evaluated using non-parametric tests and fitting a logistic regression model. A total of 123 workers participated in the study, most of them male (53.2%), aged between 31 and 40 years (42.2%), with a predominance of workers with postgraduate degrees (62.6%, n = 77), and the majority of workers (68.2%, n = 84) were performing their professional activities remotely for at least one day during the week, and 73.2% (n = 90). It was observed that 52.8% had excellent healthy eating practices, and the older their age and the greater the practice of physical activity (time and frequency), the better the workers’ healthy eating practices. When assessing quality of life, the lowest average score for healthy eating practices was in the domain of social relationships. A direct relationship of older age, social relationships, and the practice of physical activity with the best individuals’ healthy eating practices was detected. Considering that remote work continues to be adopted post-pandemic, evaluating the dietary practices, physical activity, and quality of life of workers is necessary to understand this new labour phenomenon.

It is estimated that one-quarter of the world’s population has Metabolic Syndrome (MS)(1), a key driver of growth in healthcare expenditure. Traditional approaches to treating MS through the application of standard dietary recommendations and caloric restriction have had limited success. More recent evidence suggests that novel, anti-inflammatory approaches such as replacing refined carbohydrates and ultra-processed food with unprocessed or minimally processed, lower carbohydrate foods and adapting meal timing and frequency may be more effective(2). The aim of the study was twofold: 1) To determine the effectiveness of anti-inflammatory dietary strategies for long-term weight loss and improvement in metabolic health and 2) To examine the relationships between eating behaviours and long-term weight loss. Twelve-month audit data from a UK based 12-week lifestyle program that focuses the principles of consuming an anti-inflammatory diet was analysed using repeated-measures ANOVA to examine the effects of the program on changes in weight and waist circumference. A quantitative, survey-based research design was used to retrospectively identify relationships between eating behaviours and both anti-inflammatory and pro-inflammatory dietary patterns. Multivariate regression using stepwise method was used to examine differences in weight change based on eating patterns and behaviours. Six hundred and forty-two (N = 642) participants (age = 50.4 ± 12.5 years, female 63.6%, weight = 96.1 kg ± 22.1, BMI 35.2 kg/m2 ± 7.5) demonstrated a weight loss average of 4.49 kg ± 3.78 post-lifestyle program (12 weeks). Survey respondents (N = 64) reported a maximum long term weight loss of 13.9 kg ± 11.9. Weight loss and percentage weight loss after the program was significantly predicted by daily consumption of sweet drinks and grain-based foods. The model predicted one unit increase in daily serving consumption of these foods resulted in less weight lost [2.3 kg (4.5%)]. Seventy one percent of survey respondents had maintained most or all their weight loss for more than 6 months. The model predicted change in consumption of grain-based foods, TFEQ-emotional eating score, consumption of savoury ultra-processed foods, and following an alternative dietary approach after the program were statistically significant in predicting weight loss maintenance (R2 = 0.803, F(4, 20) = 20.376, p < 0.001). The preliminary findings suggest that anti-inflammatory dietary approaches are effective and sustainable for weight loss. Eating behaviour may both support and hinder long term changes in eating patterns and whilst there are significant relationships between eating behaviour and eating patterns, the extent to which dietary patterns drive eating behaviour remains unclear.

Accumulating evidence shows associations between rapid eating and overweight. Modifying eating rate might be a potential weight management strategy without imposing additional dietary restrictions. A comprehensive understanding of factors associated with eating speed will help with designing effective interventions. The aim of this review was to synthesise the current state of knowledge on the factors associated with eating rate. The socio-ecological model (SEM) was utilised to scaffold the identified factors. A comprehensive literature search of eleven databases was conducted to identify factors associated with eating rate. The 104 studies that met the inclusion criteria were heterogeneous in design and methods of eating rate measurement. We identified thirty-nine factors that were independently linked to eating speed and mapped them onto the individual, social and environmental levels of the SEM. The majority of the reported factors pertained to the individual characteristics (n = 20) including demographics, cognitive/psychological factors and habitual food oral processing behaviours. Social factors (n = 11) included eating companions, social and cultural norms, and family structure. Environmental factors (n = 8) included food texture and presentation, methods of consumption or background sounds. Measures of body weight, food form and characteristics, food oral processing behaviours and gender, age and ethnicity were the most researched and consistent factors associated with eating rate. A number of other novel and underresearched factors emerged, but these require replication and further research. We highlight directions for further research in this space and potential evidence-based candidates for interventions targeting eating rate.

In dairy production, high feed efficiency (FE) is important to reduce feed costs and negative impacts of milk production on the climate and environment, yet little is known about the relationship between FE, eating behaviour and activity. This research communication describes how cows differing in FE, expressed as daily energy corrected milk production per unit of feed intake, differed in eating behaviour and activity. We used data from a study of 253 lactations obtained from 97 Holstein and 91 Jersey cows milked in an automatic milking system. Automated feed troughs recorded feed intake behaviour and cows wore a sensor that recorded activity from 5 to 200 d in milk (DIM). We used a mixed linear model to estimate random solutions for individual cows for traits of steps, lying and eating behaviour and calculated their correlation with FE during four periods (5–35, 36–75, 76–120 and 121–200 DIM). Separate analyses were performed for each breed and period. We found that individual level correlations between FE and behaviour traits were stronger in Jersey than in Holstein cows. Eating rate correlated weakly negatively to FE in Holstein cows and more strongly so in Jersey cows, such that efficient Jerseys were slower eaters. The physical activity of Jersey cows was weakly and negatively correlated to FE, but this was not the case in Holstein cows. We conclude that eating rate was consistently negatively associated with FE throughout lactation for Jersey cows, but not for Holstein cows.

Intuitive eating (IE) is a concept based on mind–body integration of instinct, emotion and rational thought, to improve eating behaviours, physical and mental health. Several attempts were developed to teach IE principles including text-messaging interventions given that they are easy to implement and low cost.

Mexico is going through an environmental and nutritional crisis related to unsustainable dietary behaviours. Sustainable diets could solve both problems together. This study protocol aims to develop a three-stage, 15-week mHealth randomised controlled trial of a sustainable-psycho-nutritional intervention programme to promote Mexican population adherence to a sustainable diet and to evaluate its effects on health and environmental outcomes. In stage 1, the programme will be designed using the sustainable diets, behaviour change wheel and capability, opportunity, motivation, and behaviour (COM-B) models. A sustainable food guide, recipes, meal plans and a mobile application will be developed. In stage 2, the intervention will be implemented for 7 weeks, and a 7-week follow-up period in a young Mexican adults (18–35 years) sample, randomly divided (1:1 ratio) into a control group (n 50) and an experimental group (n 50), will be divided into two arms at week 8. Outcomes will include health, nutrition, environment, behaviour and nutritional-sustainable knowledge. Additionally, socio-economics and culture will be considered. Thirteen behavioural objectives will be included using successive approaches in online workshops twice a week. The population will be monitored using the mobile application consisting of behavioural change techniques. In stage 3, the effects of the intervention will be assessed using mixed-effects models on dietary intake and quality, nutritional status, physical activity, metabolic biomarkers (serum glucose and lipid profile), gut microbiota composition and dietary water and carbon footprints of the evaluated population. Improvements in health outcomes and a decrease in dietary water and carbon footprints are expected.

Food neophobia is defined as the unwillingness to taste new foods and the avoidance of unfamiliar foods. This eating behaviour is a complex issue, and both genetic and environmental factors play a role in it. The aim of this review is to understand its relationships with dietary behaviours throughout the lifespan and to examine the impact of interventions on food neophobia. A literature search was performed using the PubMed, Web of Science, Cochrane Library and ScienceDirect databases. As a result of the screening, a total of 139 studies, seven of which were intervention studies, were included in this review. According to current evidence, food neophobia is negatively associated with the acceptance of not only novel/unfamiliar foods but also familiar foods. Many studies have shown that food neophobia is negatively associated with the hedonics and consumption of core foods, especially vegetables and fruits. Individuals with higher levels of food neophobia are less familiar with many foods, but familiarity is a prominent motivator in food choices for these individuals. Therefore, it may be considered a barrier limiting diet quality and this trend is similar for both children and adults. However, food neophobia is not an unchangeable personality trait. Intervention studies have pointed out that educational programmes and food-related activities that increase familiarity and exposure to foods and create positive attitudes towards and positive experiences with foods can reduce food neophobia. The results highlight that people with high food neophobia need more support to improve their diets and the quality of dietary behaviour.

We examined cross-sectional and longitudinal associations of dietary factors with caries experience in a population sample of 487 children aged 6–9 years at baseline examinations of the Physical Activity and Nutrition in Children (PANIC) Study. Altogether, 406 of these children attended 2-year follow-up examinations. Food consumption and eating frequency were assessed using 4-day food records, diet quality using the Baltic Sea Diet Score (BSDS) and eating behaviour using the Children’s Eating Behavior Questionnaire. Caries experience was examined clinically. The cross-sectional associations of dietary factors with caries experience at baseline were analysed using linear regression and the longitudinal associations of dietary factors with a change in caries experience over follow-up using generalised mixed-effects regression adjusted for other risk factors. A higher consumption of high-fibre grain products (standardised regression coefficient β = −0·16, P = 0·003) and milk (β = −0·11, P = 0·025) and higher BSDS (β = −0·15, P = 0·007) were associated with lower caries experience, whereas a higher consumption of potatoes (β = 0·11, P = 0·048) and emotional overeating (β = 0·12, P = 0·025) were associated with higher caries experience. Higher snacking frequency (fixed coefficient β = 0·07, P = 0·033), desire to drink (β = 0·10, P = 0·046), slowness in eating (β = 0·12, P = 0·027) and food fussiness (β = 0·12, P = 0·018) were associated with higher caries experience, whereas enjoyment of food (β = −0·12, P = 0·034) and higher BSDS (β = −0·02, P = 0·051) were associated with lower caries experience.

We aimed to evaluate the association of overweight/obesity based in BMI and purgative behaviours with body image (BI). Methods: Cross-sectional study, with probabilistic sample of 976 adolescents, aged 11–14 years, from the city of Florianópolis, Brazil. Multivariate analyses were performed. Overweight (including obesity) and four variables related to purgative methods for body weight control or eating behaviour were evaluated as outcomes, while BI satisfaction was the primary independent variable in each model. Models were controlled for age, sex, type of school (public or private), intake of fruit and vegetables, number of daily meals, and physical activity scores levels. A total of 31·4 % of adolescents wanted to enlarge their silhouette and 45·6 % wanted to reduce it. Among overweight/obese adolescents, 9·6 % were satisfied with their bodies, while 89·8 % wanted to reduce it, while among the not overweight/obese adolescents, 45·4 % wanted to enlarge their silhouette (P < 0·001). Multivariate analysis showed that the odds for overweight/obesity is higher among adolescents who wanted to reduce their silhouette (OR = 11·20; 95 % CI = 5·55, 22·58). Adolescents who want to reduce their silhouette are more likely to use diuretics (OR = 3·08; CI = 1·78, 5·32) and to use laxatives (OR = 2·10; CI = 1·20, 3·68). A significant association was also found between dissatisfaction with BI and overeating (among those who want to enlarge their silhouette: OR = 1·78; CI = 1·12, 2·85 and among those who want to reduce their silhouette: OR = 1·81; CI = 1·03, 3·19). Conclusion: BI dissatisfaction was associated with overweight/obesity, as well with overeating, and the use of purgative methods.

The Winter Conference 2021 focused on the theme of obesity and the brain, with symposia on the consequences of obesity on brain function, developments in behavioural change interventions, neurobiology of appetite regulation and obesity treatment, and personalised medicine for obesity prevention and treatment. The first plenary lecture discussed sweetness perceptions and how non-nutritive sweeteners may lead to a mismatch between metabolic signals and reward systems in the brain, and the second plenary lecture presented novel approaches to the treatment of binge-eating disorders. This short report summarises the content of these scientific sessions.

A cross-sectional study compared feeding difficulties in children aged 2–5 years fed a cows’ milk elimination diet due to food allergy with a control group on an unrestricted diet. All data were obtained online. Specific questionnaires evaluated three types of feeding difficulties: avoidant eating, picky eating and feeding problems. The median scores of feeding difficulties in the elimination diet (n 146) and control (n 109) groups were, respectively: picky eating (31 v. 27; P = 0·148), avoidant eating (3 v. 3; P = 0·508) and feeding problems (38 v. 34, P = 0·032). Picky eating was more frequent in the elimination diet (35·4 %) than in the controls (23·3 %; P = 0·042), but no difference was observed for avoidant eating (23·9 % v. 20·4 %, P = 0·508) and feeding problems (32·1 % v. 28·4 %, P = 0·541). Picky eating was associated with lower values of weight-for-age z-scores in both groups. Multivariate analyses identified associations of the three feeding difficulties with previous food refusal and/or inappetence in the elimination diet group. Current constipation and anticipatory gagging were associated with feeding difficulties in both groups. In conclusion, children on an elimination diet presented higher frequency of picky eating and higher scores of feeding problems. Picky eating was associated with lower values of weight-for-age z-scores. Food refusal and/or inappetence as clinical manifestations of food allergy were associated with feeding difficulties at the moment of the survey. Current constipation and anticipatory gagging were associated with picky eating, avoidant eating and feeding problems.

This study determined the validity, reproducibility and usability of a smartphone app – APPetite – for the measure of free-living, subjective appetite. Validity was assessed compared with the criterion tool of pen-and-paper visual analogue scale (VAS) (n 22). Appetite was recorded using APPetite and VAS, one immediately after the other, upon waking and every hour thereafter for 12 h. This was repeated the next day with the order of tool reversed. Agreement between tools was assessed using Bland–Altman analysis. Reproducibility and usability were assessed in a separate experiment (n 22) of two trials (APPetite v. VAS), separated by 7 d. Appetite was recorded in duplicate upon waking and every hour for 12 h using APPetite or VAS. Agreement between duplicate measures was assessed using Bland–Altman analysis and CV was compared between tools. Usability was assessed by comparing compliance and by qualitative evaluation. APPetite demonstrated good criterion validity with trivial bias of 1·65 units/mm·h–1 between APPetite- and VAS-derived AUC appetite scores. Limits of agreement were within a maximum allowed difference of 10 %. However, proportional bias was observed. APPetite demonstrated high reproducibility, with minimal bias (–0·578 units·h–1) and no difference in CV between APPetite and VAS (1·29 ± 1·42 % v. 1·54 ± 2·36 %, P = 0·64). Compliance was high with APPetite (92·7 ± 8·0 %) and VAS (91·6 ± 20·4 %, P = 0·81). Ninety percent of participants preferred APPetite, citing greater accessibility, simplified process and easier/quicker use. While proportional bias precludes using APPetite and VAS interchangeably, APPetite appears a valid, reproducible and highly usable tool for measuring free-living appetite in young-to-middle-aged adults.

Energy deficit is common during prolonged periods of strenuous physical activity and limited sleep, but the extent to which appetite suppression contributes is unclear. The aim of this randomised crossover study was to determine the effects of energy balance on appetite and physiological mediators of appetite during a 72-h period of high physical activity energy expenditure (about 9·6 MJ/d (2300 kcal/d)) and limited sleep designed to simulate military operations (SUSOPS). Ten men consumed an energy-balanced diet while sedentary for 1 d (REST) followed by energy-balanced (BAL) and energy-deficient (DEF) controlled diets during SUSOPS. Appetite ratings, gastric emptying time (GET) and appetite-mediating hormone concentrations were measured. Energy balance was positive during BAL (18 (sd 20) %) and negative during DEF (–43 (sd 9) %). Relative to REST, hunger, desire to eat and prospective consumption ratings were all higher during DEF (26 (sd 40) %, 56 (sd 71) %, 28 (sd 34) %, respectively) and lower during BAL (–55 (sd 25) %, −52 (sd 27) %, −54 (sd 21) %, respectively; P condition < 0·05). Fullness ratings did not differ from REST during DEF, but were 65 (sd 61) % higher during BAL (P condition < 0·05). Regression analyses predicted hunger and prospective consumption would be reduced and fullness increased if energy balance was maintained during SUSOPS, and energy deficits of ≥25 % would be required to elicit increases in appetite. Between-condition differences in GET and appetite-mediating hormones identified slowed gastric emptying, increased anorexigenic hormone concentrations and decreased fasting acylated ghrelin concentrations as potential mechanisms of appetite suppression. Findings suggest that physiological responses that suppress appetite may deter energy balance from being achieved during prolonged periods of strenuous activity and limited sleep.