Food craving, cortisol and ghrelin responses in modeling highly palatable snack intake in the laboratory

Higher morning cortisol is associated with lower intuitive eating in midlife women

BACKGROUND

Stress is associated with negative health outcomes in adults, including increased adiposity. Eating behaviors to cope with stress can have a negative effect on adiposity. There is limited research on positive eating behaviors, such as intuitive eating (IE), and their relationship to stress and adiposity. Thus, this study aimed to examine the association between stress and adiposity and to assess whether IE is a mediator of that pathway.

METHODS

Data were analyzed from a cross-sectional study of 114 women between 40-64 years of age. Participants completed in-person visits and self-reported questionnaires, including the Intuitive Eating Scale and Perceived Stress Scale. Adiposity was assessed using dual energy x-ray absorptiometry. Measurements included total body fat percentage and android/gynoid (AG) ratio as a measure of abdominal adiposity. Participants provided ten salivary cortisol samples over two days, collected upon waking, 30-, 45-, and 60-minutes after waking, and prior to bed. Several methods were used to characterize cortisol secretion and exposure, including the diurnal cortisol slope and the cortisol area under the curve with respect to ground (AUCg). Linear regression was used to assess the associations between perceived stress and IE and between features of diurnal cortisol and IE. Mediation models were tested to examine the indirect effects of IE on the relationship between perceived stress and adiposity and to test the indirect effects of IE on the relationship between cortisol measures and adiposity.

RESULTS

Linear regression analyses indicated that higher cortisol AUCg was associated with lower scores on the eating for physical reasons subscale (β: -0.01, p = 0.008). After adjusting for covariates, neither higher perceived stress nor diurnal cortisol were associated with intuitive eating. There was no evidence of mediation of the association of stress on adiposity through IE.

CONCLUSION

Our findings demonstrate a relationship between higher overall morning cortisol and lower scores on the eating for physical reasons subscale of the Intuitive Eating Scale. Future research should seek to understand how intuitive eating may be used as a technique for individuals who engage in emotional eating to cope with stress, and to prevent excess adiposity resulting from stress in midlife women.

Factors increasing the risk for food addiction in Ecuadorian students

Background

Food addiction (FA) is a construct that has gained interest in recent years, but its relevance in the Ecuadorian population has not yet been explored. The aims of this study were to explore the differences in the psychological profile (including FA) between university students from Ecuador and to identify the underlying structure of the relationships of the FA severity level through a mediational model.

Methods

The sample consisted of 972 university students, women and men (mean age: 20.1 years old, SD = 2.6), recruited from four Ecuadorian regions. The assessment tools included a unidimensional scale of FA, eating-related measures, emotion regulation state, impulsivity, and psychopathology state. Path analysis modeled the direct and indirect effects explaining the FA severity level.

Results

The results indicated that higher psychopathological levels were associated with FA. Similarly, no differences in FA were observed between the Ecuadorian regions. The path analysis suggested that older age, female sex, and higher difficulties in emotional regulation, impulsivity, negative mood, and anxiety trigger disordered eating; subsequently, more impaired eating behavior impacted the FA level.

Conclusion

FA is a complex clinical entity that includes multiple components related to eating disorders (EDs) and other mental health problems. The results of this study provide empirical knowledge for designing evidence-based prevention and treatment strategies.

Prevalence of malnutrition and its associated factors among 18,503 Chinese children aged 3-14 years

Background

Child malnutrition places a major burden on global public health. We aimed to estimate the prevalence of child malnutrition and identify its potential factors among children aged 3-14 years from Beijing and Tangshan.

Methods

We cross-sectionally recruited 18,503 children aged 3-14 years from September 2020 to January 2022, according to a stratified cluster random sampling strategy. Child malnutrition was defined according to the World Health Organization criteria. Data were analyzed by STATA software and R language.

Results

The prevalence of malnutrition among 18,503 children was 10.93%. After multivariable adjustment, seven factors significantly associated with child malnutrition were parental education (adjusted odds ratio, 95% confidence interval, p: 1.52, 1.40 to 1.67, <0.001), family income (1.23, 1.16 to 1.30, <0.001), fast food intake frequency (1.14, 1.06 to 1.21, <0.001), night meals intake frequency (1.09, 1.04 to 1.15, <0.001), eating speed (1.01, 1.01 to 1.02, <0.001), maternal obesity (0.97, 0.95 to 0.99, <0.001), and paternal obesity (0.97, 0.96 to 0.98, <0.001). The seven significant factors had better prediction performance (area under the receiver operating characteristic, 0.956) for child malnutrition.

Conclusion

Approximately 10% of Chinese children aged 3-14 years were in malnutrition status, and seven factors were found to be significant predictors for child malnutrition.

Motives and food craving: Associations with frequency of hyper-palatable food intake among college students

BACKGROUND

College food environments provide wide access to hyper-palatable foods (HPF). Palatable eating motives and craving are individual factors that may impact HPF intake. Nevertheless, no study to date has examined the relationship between these factors and frequency of HPF intake in a dormitory all-you-can-eat-style cafeteria meal, a typical college food setting.

METHODS

College students (N = 218) self-reported frequency of HPF intake at a college cafeteria meal and their frequency of HPF intake in the overall diet. Quasipoisson and logistic regression models tested whether palatable eating motives (assessed via the Palatable Eating Motives Scale) and craving (assessed via the Food Craving Inventory) were associated with the rate of HPF intake during the cafeteria meal and excess frequency of HPF intake in the overall diet.

RESULTS

Craving was associated with a 19% higher rate of HPF intake during the cafeteria meal (RR = 1.19; p = .015) and a >2-fold higher likelihood of excess frequency of HPF intake the overall diet (OR = 2.69; p < .001). Coping motive was associated with an 87% higher likelihood of excess frequency of HPF intake in the overall diet (OR = 1.87; p = .002), but not in the cafeteria meal. Reward enhancement, social and conformity motives were not significantly associated with the frequency of HPF intake in either setting.

CONCLUSIONS

Results highlight the role of craving and coping motive in the frequency of HPF intake among college students. Prevention efforts may consider targeting craving and eating to cope to potentially address frequency of HPF intake among college students.

Transcutaneous vagal nerve stimulation modulates stress-induced plasma ghrelin levels: A double-blind, randomized, sham-controlled trial

BACKGROUND

Transcutaneous cervical vagus nerve stimulation (tcVNS) has emerged as a potential treatment strategy for patients with stress-related psychiatric disorders. Ghrelin is a hormone that has been postulated to be a biomarker of stress. While the mechanisms of action of tcVNS are unclear, we hypothesized that tcVNS reduces the levels of ghrelin in response to stress.

METHODS

Using a randomized double-blind approach, we studied the effects of tcVNS on ghrelin levels in individuals with a history of exposure to traumatic stress. Participants received either sham (n = 29) or active tcVNS (n = 26) after exposure to acute personalized traumatic script stress and mental stress challenges (public speech, mental arithmetic) over a three day period.

RESULTS

There were no significant differences in the levels of ghrelin between the tcVNS and sham stimulation groups at either baseline or in the absence of trauma scripts. However, tcVNS in conjunction with personalized traumatic scripts resulted in lower ghrelin levels compared to the sham stimulation group (265.2 ± 143.6 pg/ml vs 478.7 ± 349.2 pg/ml, P = 0.01). Additionally, after completing the public speaking and mental arithmetic tests, ghrelin levels were found to be lower in the group receiving tcVNS compared to the sham group (293.3 ± 102.4 pg/ml vs 540.3 ± 203.9 pg/ml, P = 0.009).

LIMITATIONS

Timing of ghrelin measurements, and stimulation of only left vagus nerve.

CONCLUSION

tcVNS decreases ghrelin levels in response to various stressful stimuli. These findings are consistent with a growing literature that tcVNS modulates hormonal and autonomic responses to stress.

Chrononutrition and metabolic health in children and adolescents: a systematic review and meta-analysis

CONTEXT

Obesity has emerged as a global health issue for the pediatric population, increasing the need to investigate physiopathological aspects to prevent the appearance of its cardiometabolic complications. Chrononutrition is a field of research in nutritional sciences that investigates the health impact of 3 different dimensions of feeding behavior: regularity of meals, frequency, and timing of food intake.

OBJECTIVE

We carried out a systematic review and meta-analysis to investigate the association between chrononutrition in children and adolescents and the risk of overweight/obesity or a cluster of metabolic abnormalities related to glucose and lipid metabolism, blood pressure, and cardiovascular disease risk.

DATA EXTRACTION

A literature search was performed using PubMed, EMBASE, and The Cochrane Library for relevant articles published before August 2022.

DATA ANALYSIS

A total of 64 articles were included in the narrative synthesis (47 cross-sectional and 17 cohort studies), while 16 studies were included in the meta-analysis. Meta-analysis showed that non-daily breakfast consumers (≤6 d/wk) had a higher risk of overweight/obesity (odds ratio [OR], 1.45; 95% confidence interval [CI], 1.08-1.82] compared with daily breakfast eaters (7 d/wk). Similarly, irregular breakfast consumption (only 0-to-3 times/wk) increased the risk of abdominal obesity (waist-to-height ratio ≥ 0.5) compared with regular consumption (5-to-7 times/wk) (OR, 1.38; 95% CI, 1.26-1.49). There was evidence to suggest that a regular frequency of meal consumption (≥4 times/d) is preventive against overweight/obesity development compared with fewer meals (≤3 times/d) (OR, 0.83; 95% CI, 0.70-0.97). In the narrative synthesis, snacking habits showed controversial results, while food timing was the most understudied dimension.

CONCLUSION

Overall, our data indicate a potential implication of chrononutrition in affecting pediatric metabolic health; however, the evidence of this association is limited and heterogeneous. Further prospective and intervention studies with a consistent approach to categorize the exposure are needed to elucidate the importance of chrononutrition for pediatric metabolic health.

Mechanisms of improved body composition among perimenopausal women practicing Meditative Movement: a proposed biobehavioral model

OBJECTIVES

Weight gain and unfavorable body composition are prevalent among midlife/older women throughout menopause. These shifts may negatively impact health, well-being, and longevity. Efforts to attenuate weight and body composition changes are traditionally driven by manipulation of diet and/or exercise; however, sustained results are limited, possibly because the full spectrum of biobehavioral systems is not addressed by diet and exercise alone. We propose a biobehavioral model detailing mechanisms of body composition decline among perimenopausal women and the associated components of Meditative Movement (ie, tai chi, qigong, yoga) that address each of these factors.

METHODS

Based on our previous work and extensive review of the literature, we developed a multifactorial and multidimensional biobehavioral model including factors that most directly relate to body composition among perimenopausal women: 1) psychological (ie, stress and mood, mindfulness and self-compassion, body awareness), 2) behavioral (ie, sleep, physical activity, eating behaviors), and 3) physiological (ie, cortisol, estrogen). Relationships between each factor, Meditative Movement practice components, and predicted effects on body composition were explored in detail.

RESULTS

Our model describes select psychological, behavioral, and physiological factors, and potential mechanistic pathways of Meditative Movement practice driving improved changes in body composition and weight outcomes for perimenopausal women.

CONCLUSIONS

The proposed model details a novel, evidence-supported means to reduce the risk of deleterious shifts in body composition throughout perimenopause and menopause thereafter. We suggest that these changes may occur directly and/or indirectly through psychological, behavioral, and physiological mechanisms that facilitate the desired changes in body composition.

Temporal dynamics of mental imagery, craving and consumption of craved foods: an experience sampling study

Objective: According to the elaborated intrusion theory of desire, an initial thought about a wanted substance is elaborated with mental imagery, which increases craving and the probability of consuming the substance. We used an app-assisted experience sampling approach to test this theory in the context of food craving and eating.Design: Overall, 221 females (mean age = 21 years; mean body mass index = 22) reported craving, mental imagery, and food consumption six times per day (2 h intervals) for seven consecutive days. Additionally, two traits (general food craving and imagery ability) were assessed.Main outcome measures: craving intensity, food consumption.Results: The probability of eating a craved food increased if the vividness of the mental food image and craving intensity increased two hours before - independent of trait food craving and trait imagery ability. We also found evidence of controlled eating behavior, with participants consuming the food they craved in only 38% of the cases.Conclusion: Mental imagery vividness and craving intensity predict consumption of craved food. The association between craving and eating might be stronger in individuals who struggle with controlling their eating behavior. Therefore, future studies should examine these relationships in overweight/obese samples or patients with eating disorders.

Microbes, oxytocin and stress: Converging players regulating eating behavior

Oxytocin is a peptide-hormone extensively studied for its multifaceted biological functions and has recently gained attention for its role in eating behavior, through its action as an anorexigenic neuropeptide. Moreover, the gut microbiota is involved in oxytocinergic signaling through the brain-gut axis, specifically in the regulation of social behavior. The gut microbiota is also implicated in appetite regulation and is postulated to play a role in central regulation of hedonic eating. In this review, we provide an overview on oxytocin and its individual links with the microbiome, the homeostatic and non-homeostatic regulation of eating behavior as well as social behavior and stress.

Effect of COVID-19 pandemic on eating habits and lifestyle of college students in Tabriz, Iran: a cross-sectional study

Background

The pandemic of coronavirus disease (COVID-19) has influenced lifestyle behaviors and the health of populations worldwide. The purpose of this study was to determine the effects of the COVID-19 pandemic on the eating habits and lifestyle behaviors of Tabriz University of Medical Sciences students in Tabriz, Iran.

Methods

This cross-sectional study was conducted on 220 college students selected using a convenience sampling method in May-June 2022. Data were collected by the questionnaire, which included information on eating habits, physical activity, smoking, watching television, social media use, sleep, anxiety and stress, and smoking before and during the pandemic. The Chi-square test was used to analyze the association of COVID-19 with lifestyle behaviors.

Results

The median age of participants was 22.00 (IQR: 3.00) years old. The median BMI was 21.69 (IQR: 3.82) kg/m2, and 74.5% of participants had a BMI of 18.5 to 25 kg/m2. Around 34.5% of participants reported a weight gain during the pandemic. During the pandemic, students' eating habits improved by maintaining a regular meal pattern, eating a balanced diet, consuming 2-3 servings of milk or its products, consuming one or more servings of pulses, eggs, or meat per day, decreasing consumption of fast food, fried, and junk foods, adding less sugar to meals and beverages, and consuming fewer sugar-sweetened beverages and foods with high sugar (all p = 0.000). They also reported less physical activity and more sitting and screen time. Sleep time and poorer quality of sleep increased during the pandemic (p = 0.000). Feeling stress or anxiety in a day increased, and 2.2% of our participants decided to smoke. The biggest reasons for eating habits changes were less eating out, fear of coronavirus spreading through food, preferring home-cooked food, and improved knowledge about nutrition.

Conclusion

The results indicated that the eating habits of university students improved; however, participants stated increased weight gain, screen, sitting, and sleep time, declined physical activity, worse sleep quality, and feeling stress or anxiety during the COVID-19 pandemic. The findings can help to develop nutritional and behavioral recommendations for maintaining adults' health during and after the pandemic.

The Gut Microbiome and Residential Surrounding Greenness: a Systematic Review of Epidemiological Evidence

PURPOSE OF REVIEW

A healthy indigenous intestinal microbiome is essential for human health. Well-established gut microbiome determinants only explain 16% of the inter-individual variation in gut microbiome composition. Recent studies have focused on green space as a potential determinant of the intestinal microbiome. We systematically summarize all evidence concerning the association between green space and intestinal bacterial diversity, evenness, and richness indices, specific bacterial taxa, and potential underlying mechanisms.

RECENT FINDINGS

Seven epidemiological studies were included in this review. The majority of the included studies (n = 4) reported a positive association between green space and intestinal bacterial diversity, evenness, and richness, while two reported the opposite. There was little overlap between the publications regarding the association between green space and the relative abundance of specific bacterial taxa. Only a decrease in the relative abundance of Bacteroidetes, Bacteroides, and Anaerostipes and an increase in Lachnospiraceae and Ruminococcaceae were reported in multiple studies, predominantly suggesting that green space is positively associated with the intestinal microbiome composition, and subsequently with human health. Lastly, the only examined mechanism was a reduction in perceived psychosocial stress. Mechanisms indicated in blue and white represent tested or hypothesized mechanisms, respectively. The graphical abstract was created with illustrations from BioRender, Noun Project, and Pngtree.

Association between specific types of parent stressors and fast-food consumption among parents and children

INTRODUCTION

Although stress has been associated with eating behaviors, such as overeating and eating less healthy foods, the relationships between specific types of parent stressors and fast-food consumption in parents and young children have not been well studied. We hypothesized that parent perceived stress, parenting stress, and household chaos would be positively associated with fast-food consumption for parents and their young children.

METHODS

Parents of 2-5 year olds and with Body Mass Index >27 kg/m2 (N = 234, parent mean age: 34.3 (±5.7); child age: 44.9 (±13.8) months; 65.8 % from two parent households) completed surveys on parent perceived stress, parenting stress, household chaos, and their fast-food intake and that of their child.

RESULTS

In separate regression models, controlling for covariates, parent perceived stress (β = 0.21, p < 0.01; R2 = 0.10, p < 0.01), parenting stress (β = 0.26, p < 0.01; R2 = 0.13, p < 0.01), and household chaos (β = 0.25, p < 0.01; R2 = 0.12, p < 0.01) were each significantly associated with parent fast-food consumption, and separately with child fast-food consumption [Parent perceived stress (β = 0.05, p = 0.02; R2 = 0.14, p < 0.01); parenting stress (β = 0.14, p = 0.03; R2 = 0.14, p < 0.01); parent fast-food consumption (β = 0.40, p < 0.01; R2 = 0.27, p < 0.01)]. However, combined final models showed parenting stress (p < 0.01) as the only significant predictor of parent fast-food consumption, which in turn was the only significant predictor of child fast-food consumption (p < 0.01).

DISCUSSION

The findings support the inclusion of parenting stress interventions that target fast-food eating behaviors in parents, which may in turn, reduce fast-food intake in their young children.

Exploring the pathways from the power of food to food cravings in a sample of Brazilian young adults

The present study has three main objectives: a) to analyse, for the first time, the factor structure of the Control of Eating Questionnaire (CoEQ) in a Brazilian sample; b) to explore, through in-depth interviews, motivators and consequences of food cravings among participants with high scores on the CoEQ; and c) to analyse whether and how the power of food is related to food cravings. The study involved 335 young adults aged 18-30 years, balanced for sex. The CoEQ and the Power of Food Scale (PFS) were used in an online survey. The CoEQ and PFS were subjected to confirmatory factor analysis. Semi-structured interviews were also conducted with a subsample (n = 20) with high CoEQ scores. The Socratic questioning method was used for the interviews. The interviews were transcribed and analysed according to thematic content analysis. The PFS and the CoEQ showed adequate factor structure with reliable factors. The results of the qualitative analysis showed that both food availability and seeking relief from stressors serve as motives for food cravings. Concern for health and weight gain were cited as consequences of cravings, as was seeking distraction to cope with these cravings. It was found that the PFS aggregate factor was a significant influencing factor for craving control (β = 0.604; p < 0.001), craving for savoury (β = 0.382; p < 0.001), craving for sweet (β = 0.414; p < 0.001) and positive mood (β = -0.198; p < 0.001). The findings suggest that the relationship between food cravings and the power of food is significant in today's obesogenic environment.

The association between anxiety sensitivity and food cravings among individuals seeking treatment for weight-related behaviors

BACKGROUND

A better understanding of risk-factors associated with state-like food cravings may be one clinically relevant component in an effort to better understand obesity. Existing work has shown anxiety sensitivity (AS) to be a significant risk factor for increased cravings across a variety of health behaviors (e.g., smoking, alcohol use). Yet, no work has examined the relationship between AS and state-like food cravings. Therefore, the current study sought to examine the association between AS and a variety of state-like food cravings, including: (1) an intense desire to eat, (2) anticipation of relief from negative states and feelings/improvement in mood that may result from eating, (3) obsessive preoccupation with food or lack of control over eating, and (4) craving as a physiological state.

METHODS

Participants included 161 (Mage = 31.58, SD = 10.71; 60.9 % female) individuals seeking treatment for weight-related behaviors.

RESULTS

Results indicated that elevated AS was associated with reinforcement-based and physiological food cravings.

CONCLUSION

Our findings indicate that there may be clinical utility in screening for AS among individuals seeking treatment for weight-related behaviors in efforts to better understand specific types of food craving.

The Barriers to Sustainable Nutrition for Sustainable Health among Zayed University Students in the UAE

Unhealthy and unsustainable nutrition is a major concern globally, including in the United Arab Emirates. Although many education programs have been conducted, diet-related illnesses remain prevalent. This study aims to identify the barriers between knowledge and practice of sustainable healthy diets to achieve long-term health, among students of Zayed University in the United Arab Emirates. An online questionnaire was sent to Zayed University (ZU) students over 18 years of age, using snowball sampling. The participants achieved a mean score of 5.6 out of 11 in nutritional knowledge, and a mean score of 3.4 out of 6 in healthy habits. The only barrier that significantly affected dietary habits was not knowing how to plan a diet (p = 0.025). Accordingly, having good nutritional knowledge was significantly related to improved dietary habits (p < 0.001). In addition, school curriculums (p = 0.004), doing one’s own research (p < 0.001), and social media (p < 0.001) were significantly related to improved nutritional knowledge. The most commonly reported motivators for a healthier diet were “to keep their body healthy for a long time” and “to maintain a healthy weight” (72.6% and 70.1%, respectively). Overall, among ZU students the most significant barrier to achieving sustainable healthy nutrition was lack of knowledge. Education methods such as school curriculums, individual research, and social media were effective. Topics such as how to plan a diet, how to keep the body healthy, and how to maintain a healthy weight are of general interest.

Neuropeptide Y interaction with dopaminergic and serotonergic pathways: interlinked neurocircuits modulating hedonic eating behaviours

Independent from homeostatic needs, the consumption of foods originating from hyperpalatable diets is defined as hedonic eating. Hedonic eating can be observed in many forms of eating phenotypes, such as compulsive eating and stress-eating, heightening the risk of obesity development. For instance, stress can trigger the consumption of palatable foods as a type of coping strategy, which can become compulsive, particularly when developed as a habit. Although eating for pleasure is observed in multiple maladaptive eating behaviours, the current understanding of the neurobiology underlying hedonic eating remains deficient. Intriguingly, the combined orexigenic, anxiolytic and reward-seeking properties of Neuropeptide Y (NPY) ignited great interest and has positioned NPY as one of the core neuromodulators operating hedonic eating behaviours. While extensive literature exists exploring the homeostatic orexigenic and anxiolytic properties of NPY, the rewarding effects of NPY continue to be investigated. As deduced from a series of behavioural and molecular-based studies, NPY appears to motivate the consumption and enhancement of food-rewards. As a possible mechanism, NPY may modulate reward-associated monoaminergic pathways, such as the dopaminergic and serotoninergic neural networks, to modulate hedonic eating behaviours. Furthermore, potential direct and indirect NPYergic neurocircuitries connecting classical homeostatic and hedonic neuropathways may also exist involving the anti-reward centre the lateral habenula. Therefore, this review investigates the participation of NPY in orchestrating hedonic eating behaviours through the modulation of monoaminergic pathways.

A Longitudinal Study of Life Trauma, Chronic Stress and Body Mass Index on Weight Gain over a 2-Year Period

The United States is facing an alarming and increasing obesity epidemic. Stress is associated with obesity, but specific longitudinal effects of life trauma on weight gain have not been assessed. Here we examined if life trauma and chronic stress predicted weight gain while also measuring the impact of body mass index (BMI). Life trauma and chronic stress were assessed with the Cumulative Adversity Interview (CAI). Weight and BMI were captured repeatedly over a two-year period. Results show significant increases in weight gain over time. Individuals with obesity (IOb) reported significantly higher levels of life trauma at the onset compared to overweight (IOw) and lean individuals (Il). Greater numbers of trauma events were associated with increased weight gain for both IOb and IOw but not for Il. Increased chronic stress was not consistently associated with weight gain over time. Current findings suggest the need to address trauma coping, especially in vulnerable individuals to prevent greater weight gain and curb obesity-related health outcomes.

Chrono-communication and cardiometabolic health: The intrinsic relationship and therapeutic nutritional promises

Circadian rhythm, an innate 24-h biological clock, regulates several mammalian physiological activities anticipating daily environmental variations and optimizing available energetic resources. The circadian machinery is a complex neuronal and endocrinological network primarily organized into a central clock, suprachiasmatic nucleus (SCN), and peripheral clocks. Several small molecules generate daily circadian fluctuations ensuring inter-organ communication and coordination between external stimuli, i.e., light, food, and exercise, and body metabolism. As an orchestra, this complex network can be out of tone. Circadian disruption is often associated with obesity development and, above all, with diabetes and cardiovascular disease onset. Moreover, accumulating data highlight a bidirectional relationship between circadian misalignment and cardiometabolic disease severity. Food intake abnormalities, especially timing and composition of meal, are crucial cause of circadian disruption, but evidence from preclinical and clinical studies has shown that food could represent a unique therapeutic approach to promote circadian resynchronization. In this review, we briefly summarize the structure of circadian system and discuss the role playing by different molecules [from leptin to ghrelin, incretins, fibroblast growth factor 21 (FGF-21), growth differentiation factor 15 (GDF15)] to guarantee circadian homeostasis. Based on the recent data, we discuss the innovative nutritional interventions aimed at circadian re-synchronization and, consequently, improvement of cardiometabolic health.

Changes in fast food intake in Iranian households during the lockdown period caused by COVID-19 virus emergency, National Food and Nutrition Surveillance

Background

Fast foods, though very popular, are commonly known as unhealthy foods. However, coronavirus pandemic may have influenced on food choices of the general population. This study investigated the changes in fast food consumption during epidemic lockdown 2020.

Materials and Methods

This study was part of a nationwide survey having been conducted using a web‐based electronic self‐administered questionnaire. The questionnaire link was extensively distributed among the whole population both through popular social media platforms and by nutrition and health workers of health offices and medical universities of all provinces. The questionnaire included questions about socio‐demographic characteristics, changes in frequency of fast food consumption as compared with before pandemic, and the reasons for these changes.

Results

A total of 21,290 households took part in the study of whom 89.8% were male‐headed, and almost 74% were from urban areas. Decrease in fast food consumption was reported by 74.8%, while increase in fast food consumption was reported by 2% of the households during the COVID‐19 quarantine. Among those who decreased their fast food consumption, about 82% had completely omitted them from their food baskets. Fear of contamination of fast foods by coronavirus and increase in the number of people at home were the most and the least frequent reasons for decreasing fast food consumption, respectively.

Conclusion

Fast food consumption has dramatically decreased during the lockdown period in Iranian households. Though it may be considered a pleasant offshoot of disastrous COVID‐19 epidemic, the foods replaced fast foods in Iranian households and the overall health consequences warrant further studies.

Assessing the role of ghrelin and the enzyme ghrelin O-acyltransferase (GOAT) system in food reward, food motivation, and binge eating behavior

The peripheral peptide hormone ghrelin is a powerful stimulator of food intake, which leads to body weight gain and adiposity in both rodents and humans. The hormone, thus, increases the vulnerability to obesity and binge eating behavior. Several studies have revealed that ghrelin's functions are due to its interaction with the growth hormone secretagogue receptor type 1a (GHSR1a) in the hypothalamic area; besides, ghrelin also promotes the reinforcing properties of hedonic food, acting at extra-hypothalamic sites and interacting with dopaminergic, cannabinoid, opioid, and orexin signaling. The hormone is primarily present in two forms in the plasma and the enzyme ghrelin O-acyltransferase (GOAT) allows the acylation reaction which causes the transformation of des-acyl-ghrelin (DAG) to the active form acyl-ghrelin (AG). DAG has been demonstrated to show antagonist properties; it is metabolically active, and counteracts the effects of AG on glucose metabolism and lipolysis, and reduces food consumption, body weight, and hedonic feeding response. Both peptides seem to influence the hypothalamic-pituitary-adrenal (HPA) axis and the corticosterone/cortisol level that drive the urge to eat under stressful conditions. These findings suggest that DAG and inhibition of GOAT may be targets for obesity and bingeing-related eating disorders and that AG/DAG ratio may be an important potential biomarker to assess the risk of developing maladaptive eating behaviors.

Decoding the Role of Gut-Microbiome in the Food Addiction Paradigm

Eating behaviour is characterised by a solid balance between homeostatic and hedonic regulatory mechanisms at the central level and highly influenced by peripheral signals. Among these signals, those generated by the gut microbiota have achieved relevance in recent years. Despite this complex regulation, under certain circumstances eating behaviour can be deregulated becoming addictive. Although there is still an ongoing debate about the food addiction concept, studies agree that patients with eating addictive behaviour present similar symptoms to those experienced by drug addicts, by affecting central areas involved in the control of motivated behaviour. In this context, this review tries to summarise the main data regarding the role of the gut microbiome in eating behaviour and how a gut dysbiosis can be responsible for a maladaptive behaviour such as “food addiction”.

Influence of COVID-19 on lifestyle behaviors in the Middle East and North Africa Region: a survey of 5896 individuals

BACKGROUND

Coronavirus disease (COVID-19) pandemic has affected health and lifestyle behaviors of people globally. This project aims to identify the impact of COVID-19 on lifestyle behavior of individuals in the Middle East and North Africa (MENA) region during confinement.

METHODS

We conducted an online survey in 17 countries (Egypt, Jordan, United Arab Emirates, Kuwait, Bahrain, Saudi Arabia, Oman, Qatar, Yemen, Syria, Palestine, Algeria, Morocco, Libya, Tunisia, Iraq, and Sudan) from the MENA region on August and September 2020. The questionnaire included self-reported information on lifestyle behaviors, including physical activity, eating habits, smoking, watching television, social media use and sleep before and during the pandemic. Logistic regression was performed to analyze the impact of COVID-19 on lifestyle behaviors.

RESULTS

A total of 5896 participants were included in the final analysis and 62.8% were females. The BMI of the participants was 25.4 ± 5.8 kg/m2. Around 38.4% of the participants stopped practicing any physical activities during the confinement (P < 0.001), and 57.1% reported spending more than 2 h on social media (P < 0.001). There were no significant changes in smoking habits. Also, 30.9% reported an improvement in their eating habits compared with 24.8% reported worsening of their eating habits. Fast-food consumption decreased significantly in 48.8% of the study population. This direct/indirect exposure to COVID-19 was associated with an increased consumption of carbohydrates (OR = 1.09; 95% CI = 1.02-1.17; P = 0.01), egg (OR = 1.08; 95% CI = 1.02-1.16; P = 0.01), sugar (OR = 1.09; 95% CI = 1.02-1.16; P = 0.02), meat, and poultry (OR = 1.13; 95% CI = 1.06-1.20; P < 0.01). There was also associated increase in hours spent on watching television (OR = 1.07; 95% CI = 1.02-1.12; P < 0.01) and social media (OR = 1.09; 95% CI = 1.01-1.18; P = 0.03). However, our results showed a reduction in sleeping hours among those exposed to COVID-19 infection (OR = 0.85; 95% CI = 0.77-0.94; P < 0.01).

CONCLUSIONS

The COVID-19 pandemic was associated with an increase in food consumption and sedentary life. Being exposed to COVID-19 by direct infection or through an infected household is a significant predictor of amplifying these changes. Public health interventions are needed to address healthy lifestyle behaviors during and after the COVID-19 pandemic.

Measurement of Motivation States for Physical Activity and Sedentary Behavior: Development and Validation of the CRAVE Scale

Physical activity, and likely the motivation for it, varies throughout the day. The aim of this investigation was to create a short assessment (CRAVE: Cravings for Rest and Volitional Energy Expenditure) to measure motivation states (wants, desires, urges) for physical activity and sedentary behaviors. Five studies were conducted to develop and evaluate the construct validity and reliability of the scale, with 1,035 participants completing the scale a total of 1,697 times. In Study 1, 402 university students completed a questionnaire inquiring about the want or desire to perform behaviors "at the present moment (right now)." Items related to physical activity (e.g., "move my body") and sedentary behaviors (e.g., "do nothing active"). An exploratory structural equation model (ESEM) revealed that 10 items should be retained, loading onto two factors (5 each for Move and Rest). In Study 2, an independent sample (n = 444) confirmed these results and found that Move and Rest desires were associated with stage-of-change for exercise behavior. In Study 3, 127 community-residing participants completed the CRAVE at 6-month intervals over two years- two times each session. Across-session interclass correlations (ICC) for Move (ICC = 0.72-0.95) and Rest (ICC = 0.69-0.88) were higher than when they were measured across 24-months (Move: ICC = 0.53; Rest: ICC = 0.49), indicating wants/desires have state-like qualities. In Study 4, a maximal treadmill test was completed by 21 university students. The CRAVE was completed immediately pre and post. Move desires decreased 26% and Rest increased 74%. Changes in Move and Rest desires were moderately associated with changes in perceived physical fatigue and energy. In Study 5, 41 university students sat quietly during a 50-min lecture. They completed the CRAVE at 3 time points. Move increased 19.6% and Rest decreased 16.7%. Small correlations were detected between move and both perceived energy and tiredness, but not calmness or tension. In conclusion, the CRAVE scale has good psychometric properties. These data also support tenets of the WANT model of motivation states for movement and rest (Stults-Kolehmainen et al., 2020a). Future studies need to explore how desires to move/rest relate to dynamic changes in physical activity and sedentarism.

A Laboratory-Based Study of the Priming Effects of Food Cues and Stress on Hunger and Food Intake in Individuals with Obesity

OBJECTIVE

This study aimed to assess the effects of exposures to food cues and stress on hunger and food intake and examine whether cue responses differ by weight status.

METHODS

In a laboratory-based experimental study, participants (n = 138) were exposed to stress, neutral, and food cues delivered using an individualized script-driven imagery task on three separate days. After each cue exposure, participants ate high- and low-calorie snack foods ad libitum (Food Snack Test). Hunger was measured by visual analog scales.

RESULTS

Food cues elicited significantly greater increases in hunger compared with neutral and stress stimuli. Cue-induced hunger did not differ by weight status. Participants consumed a similar number of total calories across stimuli. In response to food cue provocation, participants with obesity consumed [mean (SE)] 81.0% (4.0%) of calories from high-calorie foods, which was significantly greater than participants with normal weight (63.5%  [3.6%]; P = 0.001). After the stress cue, participants with obesity consumed 81.4% (4.0%) of calories from high-calorie foods, which was significantly more than participants with normal weight (70.2% [3.6%]; P = 0.04). Energy intake from high-calorie foods did not differ by weight status after the neutral cue.

CONCLUSIONS

Among individuals with obesity, exposure to food and stress cues shifted consumption to high-calorie snack foods within a well-controlled experimental setting.

Brain-gut-microbiome interactions in obesity and food addiction

Normal eating behaviour is coordinated by the tightly regulated balance between intestinal and extra-intestinal homeostatic and hedonic mechanisms. By contrast, food addiction is a complex, maladaptive eating behaviour that reflects alterations in brain-gut-microbiome (BGM) interactions and a shift of this balance towards hedonic mechanisms. Each component of the BGM axis has been implicated in the development of food addiction, with both brain to gut and gut to brain signalling playing a role. Early-life influences can prime the infant gut microbiome and brain for food addiction, which might be further reinforced by increased antibiotic usage and dietary patterns throughout adulthood. The ubiquitous availability and marketing of inexpensive, highly palatable and calorie-dense food can further shift this balance towards hedonic eating through both central (disruptions in dopaminergic signalling) and intestinal (vagal afferent function, metabolic endotoxaemia, systemic immune activation, changes to gut microbiome and metabolome) mechanisms. In this Review, we propose a systems biology model of BGM interactions, which incorporates published reports on food addiction, and provides novel insights into treatment targets aimed at each level of the BGM axis.

Ghrelin as a Stress Hormone: Implications for Psychiatric Illness

The stress response is an adaptive means of maintaining physiological homeostasis in the face of changing environmental conditions. However, protracted recruitment of stress systems can precipitate wear and tear on the body and may lead to many forms of disease. The mechanisms underlying the connection between chronic stress and disease are not fully understood and are likely multifactorial. In this review, we evaluate the possibility that the hormone ghrelin may contribute to the pathophysiology that follows chronic stress. Since ghrelin was discovered as a pro-hunger hormone, many additional roles for it have been identified, including in learning, memory, reward, and stress. We describe the beneficial effects that ghrelin exerts in healthy mammals and discuss that prolonged exposure to ghrelin has been linked to maladaptive responses and behaviors in the realm of psychiatric disease. In addition, we consider whether chronic stress-associated altered ghrelin signaling may enhance susceptibility to posttraumatic stress disorder and comorbid conditions such as major depressive disorder and alcohol use disorder. Finally, we explore the possibility that ghrelin-based therapeutics could eventually form the basis of a treatment strategy for illnesses that are linked to chronic stress and potentially also ghrelin dysregulation, and we identify critical avenues for future research in this regard.

Late Eating Is Associated with Obesity, Inflammatory Markers and Circadian-Related Disturbances in School-Aged Children

Late eating has been shown to promote metabolic dysregulation and to be associated with obesity in adults. However, few studies have explored this association in children. We compared the presence of obesity, metabolic alterations and circadian-related disturbances between school-aged children who were early dinner eaters (EDE) or late dinner eaters (LDE). School-age children (n = 397; 8-12 years; mean BMI (range): 19.4 kg/m² (11.6-35.1); 30.5% overweight/obesity) from Spain were classified into EDE and LDE, according to dinner timing (Median: 21:07). Seven-day-dietary-records were used to assess food-timing and composition. Non-invasive tools were used to collect metabolic biomarkers (saliva), sleep and circadian-related variables (body-temperature and actigraphy). Compared to EDE, LDE were more likely to be overweight/obese [OR: 2.1 (CI: 1.33, 3.31); p = 0.002], and had higher waist-circumference and inflammatory markers, such as IL-6 (1.6-fold) (p = 0.036)) and CRP (1.4-fold) than EDE (p = 0.009). LDE had alterations in the daily patterns of: (a) body-temperature, with a phase delay of 26 min (p = 0.002), and a reduced amplitude (LDE = 0.028 (0.001) and EDE = 0.030 (0.001) (Mean (SEM); p = 0.039); (b) cortisol, with a reduced amplitude (LDE = 0.94 (0.02) and EDE = 1.00 (0.02); p = 0.035). This study represents a significant step towards the understanding of novel aspects in the timing of food intake in children.

Violence and obesogenic behavior among adolescents aged 12-15 years from 62 countries: A global perspective

Exposure to violence may be associated with increased risk for obesogenic behavior among adolescents but studies providing a global perspective are lacking. The aim of this work was to assess the relationship between violence and obesogenic behaviors among young adolescents from 62 countries. Cross-sectional data from the Global School-based Student Health Survey 2009-2016 were analyzed. Information on violence (intentional injury, physical attack, physical fight) and obesogenic behavior (anxiety-induced sleep problems, low physical activity, sedentary behavior, fast-food consumption, carbonated soft-drink consumption) were self-reported. Associations were analyzed using meta-analysis based on country-wise multivariable logistic regression analyses. A total of 165,380 adolescents aged 12-15 years [mean (SD) age 13.8 (1.0) years; 50.9% boys] were included in the analysis. All types of violence were positively associated with higher odds for all types of obesogenic behavior with the exception of low physical activity. Associations were particularly pronounced for anxiety-induced insomnia. In contrast, intentional injury (OR = 0.72; 95%CI = 0.64-0.81) and physical fight (OR = 0.90; 95%CI = 0.86-0.95) were associated with lower odds for low physical activity. In this large global sample of adolescents, exposure to violence was associated with all obesogenic behaviors apart from low physical activity. Multidimensional government programs and policies addressing exposure to violence among young adolescents may lead to reduction in obesogenic behavior and hence curtail the global obesity epidemic.