Diet and behavior

This recent 2019 study provides a novel look into the importance of breakfast intake on cognitive development in primary and middle school students. Yao and co. (2019) used the academic quality monitoring data of basic education students in Jiangsu Province to measure the academic performance of the students. Skipping breakfast was found to be common in students in primary, secondary and middle school. Many factors are involved in determining whether a student has breakfast or not. The analyses demonstrated positive associations between the frequency of breakfast intake and student achievement. Those students in primary school who had breakfast every day in a week scored 31.322 points higher in academic performance than those who did not. The trend continues into middle school; as a 31.355 points difference in performance was observed between the students who had breakfast each day of the week and those who did not, in favour of those who consistently ate breakfast. It is evident in these results, having breakfast every day has a significant effect on cognitive development of young school students in China.

Of the students of Qazvin University of Medical sciences in Iran, 541 academics took part in this study evaluating the association between well-being and breakfast consumption, and fruit and vegetable intake. The web-based questionnaires completed assessed the students’ happiness, breakfast, fruit and vegetable consumption, and socio-economic and demographic information. The results showed a statistically significant improvement in happiness of those science students who were eating breakfast, consuming a greater number of meals, and more fruits and vegetables. The people who reported the highest satisfaction scores were those who: ate breakfast each day; consumed more than 8 portions of fruits and vegetables daily; and had 3 meals as well as 1-2 snacks per day. The researchers concluded a higher happiness score can be associated with a healthier diet behavior pattern in science students in Iran.

As one of the first reports of its kind, Matsumoto et. al (2020) investigated whether there was a link between skipping breakfast and the intake of adequate amounts of nutrients in junior high school female students. A self-administered diet history questionnaire was completed by each student (total 516) to identify dietary habits, while a cut point method was used for the nutrient intake adequacy where each diet was assessed based on estimated requirement for 14 nutrients (as per dietary reference intakes for Japanese, 2015 version) and on dietary goal values for 5 nutrients. The study sample was split up into 2 groups based on breakfast consumption frequency: breakfast daily consumers; and breakfast skippers (0-6 days/week). It was found that breakfast consumers ate more vegetables, fruit, dairy products and more frequently consumed the adequate levels of calcium, iron, zinc, potassium, and vitamins A, B1, C, compared to breakfast skippers. The results from this study suggest that skipping breakfast was related to insufficient vitamin and mineral intake among Japanese junior high school students.

Since most adolescents eat at least one snack per day and snacking becomes very important in dietary counseling and public health strategies for obesity prevention, this study examined how snacking behaviors can be linked to diet and weight status among 2793 school pupils. The students underwent anthropometric measurements, in addition to completing food frequency questionnaires and surveys on snacking behaviors to analyse intake of energy-dense snack foods, total number of snacks consumed, frequency of eating snacks prepared away from home, and how often the adolescents snacked while watching television. The results showed an average intake of 2.2 energy dense snack servings per day, averaging 4.3 total number of snacks daily and 3.2 average occurrence of eating purchased snacks during one week. Two-thirds of the young subjects reported that while they watch television they occasionally, usually or always have a snack. These measures of snacking behaviors were directly associated (p<0.01) with higher energy, lower fruits/vegetables, and more frequent eating at fast food restaurants, but daily servings of energy dense foods were not found to be associated with daily servings of sugar-sweetened beverages. Snacking behaviors were inversely related to BMI z scores although a direct relation between BMI z scores and daily servings of energy dense snacks was found. From these findings, it can be suggested that snacking is a risk factor for poor dieting in US adolescents but unless energy dense food products are consumed, snacking may not consistently contribute to becoming overweight.

Since there is a lack of knowledge about how children conceptualise food and the factors involved in their decision making processes according to Ogden and Roy-Stanley (2020), a qualitative study was designed to explore children’s comprehension of food and how their food related decisions are affected. This think-aloud study recruited 27 children all of the ages 9-10, who voiced their thoughts while making different meals and snacks using pictures of food. The results from the thematic analysis revealed the drivers of food decisions were hunger, health, personal liking, emotions and availability while the sources of these drivers included parents, peers and their routine. The food was often thought of as good or bad. Using these themes, the degree of deliberation in the children could be seen when making decisions which could be identified as either automatic, considered or sanctioned. The children were found to be in a transition stage, shifting between a passive child whose decisions are made for them to an active kid with autonomy and agency. Ogden and Roy-Stanley believe the results illustrate the ways in which children begin to internalise messages of others as they grow older, which enables them to take ownership of their own eating behavior.

This Italian study published in 2018 aimed to evaluate the differences in components of the Mediterranean Diet among primary and secondary school children and adolescents (ages 6-16) living in northern Italy, and also to analyse its association with weight status. The sample population (n=669) was picked from 5 schools of Novara. The diet adherence, measured by the KIDMED (Mediterranean Diet Quality Index) questionnaire, was mostly average (63.7% scored average score), while 16.7% of the subjects showed poor adherence and 19.6% of the students scored highly in terms of adherence to the Mediterranean diet. The data demonstrated younger children exhibited unhealthy behaviors, also showing poor adherence was significantly more prevalent in primary school children than in secondary school (20.7% vs 13.7%, p< 0.04). Besides male gender and primary school, in Italian children, the risk of being overweight was directly associated with eating at fast-food restaurants (OR: 1.890), and inversely with both the consumption of vegetables more than once a day (OR: 0.588), and taking in olive oil at home (OR: 0.382). In children of other origins, the risk of being overweight was linked to skipping breakfast (OR = 16.046) and consuming commercial baked goods or pastries for breakfast (OR =10.255). Furthermore, mixed behavior was observed among the non-Italian children, with both traditional healthy and unhealthy foods chosen by this subgroup. The study found that the overall KIDMED score correlated with height (p<0.005) and that the Mediterranean dietary pattern is being replaced by poor food quality in children and adolescents of northern Italy, particularly in younger children. Archero et. al (2018) recommend tailored nutritional programs, given that the association between risk of becoming overweight and different components of the Mediterranean diet were dependent on ethnic origins.

Mounayer and colleagues (2019) state that Mediterranean countries have witnessed a decrease in adherence to their style of diet and have adopted a more westernised dietary pattern recently, so evaluates the association between Mediterranean diet adherence with sociodemographic, lifestyle and anthropometric factors among Lebanese high school students, specifically looking at the correlation between low adherence and breakfast consumption. Six hundred adolescents (268 boys: 332 girls) aged 15-18 were randomly selected from private and public schools in Beirut and Mount Lebanon. Questionnaires and anthropometric measurements were obtained, while the Mediterranean Diet Quality Index for children and adolescents was also utilised to determine diet adherence. While girls had a significantly higher adherence rate than the boys (64.2% vs 35.8%, p<0.001), a high proportion of the total subjects showed low adherence (43%). Lower adherence to the Mediterranean diet, incidentally, was associated with high risk of obesity (15.5%), skipping breakfast (69.4%), and unhealthy breakfast choices (17.4%). A significantly higher adherence to the Mediterranean diet was seen among the younger adolescents (47.4%), students from public schools (92.6%) and those with the highest grades (25.3%) compared to private school go-ers (7.4%) and older adolescents (18.9%). Mounayer et. al (2019) at the end of the study calls for increased awareness in Lebanese schools, and more support for the children to adhere to the Mediterranean diet, in order to prevent a rise in metabolic diseases in the future.

In this 2019 cross-sectional study, students from four elementary school classrooms were presented with a buffet of apple snack items varying in degree of food processing involved in manufacturing the product (unprocessed, minimally processed, processed and ultra-processed) and were asked to complete a survey on taste of these snacks, to characterise the choices, consumption, and taste preferences of the adolescents. The results indicated students enjoyed the taste of and selected greater quantities of ultra-processed snack foods (M=2.72, M=2.20 in servings) compared to minimally processed (M=1.92, M=0.56) and unprocessed (M=2.32, M=0.70). The study found a linear relationship between the selection and consumption quantities for each snack food item (R2 = 0.88). In conclusion, there was more appeal and consumption increased among elementary school students as processing levels were raised in apple food snacks, possibly explaining the high level of diet-related diseases and nutrient deficiencies across adolescents in America. This study also exposed the need for food and nutrition education, food product development and marketing efforts to improve adolescents’ food choices and to make less-processed snack food options more appealing and accessible to diverse customers.

This 2018 randomised, crossover, controlled feeding study compared the perceptions of hunger, fullness and palatability in response to a low added sugar (AS) adequate fiber diet (LASAF; 5% total energy from AS and 13.5 g fiber/1000 kcal) and a high AS low fiber diet (HASLF; 25% total energy form AS and 8.2 g/1000 kcal). The sample population (n=32, 47% male, age 15.3 ± 1.6 yrs., BMI percentile: 47 ± 4) consumed calorie-matched LASAF and HASLF diets for 7 days, separated by a 4 week washout, with bodyweight monitored daily and hunger, fullness, and palatability assessed after each feeding period. The result showed participants remained weight stable, and no differences in weight change was detected between diet conditions. The adolescents reported less hunger and greater fullness on the LASAF compared to the HASLF, whereas no difference in palatability was found between the diets. Since the low added sugar adequate fiber diet was perceived to be as palatable as the high added sugar diet but more satiating, the researchers call for LASAF diets to be investigated further as a strategy for weight control in adolescents.

Fardet in 2016 tested the hypothesis that was based on a data set of 98 ready-to-eat foods, that the degree of food processing would correlate with the satiety index (SI) and glycaemic response [evaluated using the Glycaemic Index (GI) and the glycemic glucose equivalent (GGE)]. Foods were clustered within three processing groups based on the international NOVA classification: raw and minimally processed foods; processed foods; and ultra-processed foods [industrial formulations of substances extracted or derived from food and additives, typically with five or more and usually many (cheap) ingredients]. Fardet (2016) discovered strong correlations between GGE, SI and the degree of food processing, while GI was not associated with the degree of processing. The conclusion was drawn that the more processed the food was, the greater the glycaemic response and the lower its satiety potential. This study suggests that complex, natural, minimally and/or processed foods should be consumed rather than highly unstructured and ultra-processed foods when choosing weakly hyperglycaemic and satiating foods.

According to Hilger et. al (2017), young adults have been neglected in health promotion strategies which is why this study aimed to investigate a total of 689 university students from all over Germany on their baseline dietary intake, common barriers to healthy eating, and changes in eating behavior since their first day in university. The data was taken from the cross-sectional online survey in the Nutrition and Physical Activity Study (NuPhA), which recruited students from more than 40 universities. Hilger, Loerbroks and Diehl (2017) found that there was room for improvement in terms of consumption of certain food groups such as fruits and vegetables. Also identified were the main barriers to healthy eating for the academics: lack of time due to studies; lack of healthy meals at the university canteen; and the high prices of healthy food. Cluster analysis indicated the possibility that these barriers to consuming healthy foods in university may only affect specific subgroups such as first-year students. Since matriculation, changes in dietary behavior included the consumption of meat, fish and regular meals but this suggests future qualitative studies are warranted to explore the reason for these changes in behavior, hopefully producing useful information for health promotion strategies in the university setting.

An increasing number of students are concerned about their body shape and body mass index (BMI) and thereby develop disordered eating attitudes (DEAs) and engage in unhealthy weight control behaviors, which is why this 2017 Egyptian study’s objective was to measure how common DEAs are among students from Ain Shams university and to identify the barrier to healthy eating and physical activity for these students. A sample of 445 academics (aged 17-26, 40.7:59.3 male:female) from different faculties were assessed on eating attitudes using the Eating Attitude Test-26 questionnaire, along with their height and weight measurements in order to calculate their BMI. The research found that the majority of the students (50.8%) had normal BMI, with around 39% reported to be either overweight or obese. DEAs were observed in 73.3% of the participants, although no significant association could be made between presence of DEAs and variables such as age, sex, faculty, and BMI. The biggest barrier to both physical activity and healthy eating was lack of time. Since the prevalence of obesity and DEAs were high in this student population, this highlights more effort is required to help youths control their body weights and correct unhealthy behaviors.

Kyrkou et. al (2018) compared the dietary habits of university students residing away from the family home in two different time periods (2006 and 2016), and also explored the possible impact of gender on the behavioral changes in nutritional choices among the same target population. A total of four hundred and five university students (242 in 2006; 163 in 2016) were assessed on their diets using the food frequency questionnaire, while data on demographic and lifestyle factors were also collected. The consumption of several plant-based foods increased over the 10 years, indicating a generally positive change in the students’ eating habits. Gender was significantly associated with body mass index (BMI) and changes in dietary attitudes. The authors believe that factors such as the budgetary constraints facing Greece in the last decade, the rise in nutritional awareness and other socio-cultural factors may explain the transition towards healthier and more balanced dietary habits. What would be useful is to be able to deeply understand these relations in order to foster nutritional education and additively improve the effectiveness of health promotion campaigns.

Young adults attending community mental health services took part in this 2020 study, which aimed to comprehensively assess dietary consumption, nutritional knowledge and food addiction in young people with mental illness. In this three-arm cross-sectional study, those 16-25 year olds (n=30) who were included in this experiment had either first-episode psychosis (FEP)(10), were at ultra-high risk for psychosis (UHR)(10) or depression/anxiety (10). The participants were asked to complete 3 validated questionnaires: Australian Eating Survey; General Nutrition Knowledge Questionnaire-Revised; and Yale Food Addiction Score Questionnaire. Forty-three percent of the energy intake by the subjects was obtained from energy-dense, non-nutritious foods, even higher than the recommended upper limit (<15%) and the levels reported in the general population (35%). Prevalence of food addiction was 37% and mean food addiction symptom score was 3.3 ± 3.7. Although the difference was not statistically significant, nutrition knowledge was lower in individuals with FEP and UHR than the depression/anxiety group. Since unhealthy dietary consumption was observed in the early stages of mental illness, the consensus was that this likely leads to poor future physical health, and thus there needs to be more studies on the role of food addiction in those with mental illnesses.

Larson and her team (2017) surveyed a total of 2540 adolescents in 2009-2010 to identify individual and environmental influences that make this population eat energy-dense nutrient-poor snack foods. The aim was to inform strategies for reducing the adolescents’ intake of energy-dense snacks. The participants selected from Minneapolis-St. Paul, Minnesota schools were 54% female, 80% non-white, and had the average age of 14.5 ± 2.0. Daily servings of energy-dense snack food were assessed using a food frequency questionnaire that asked about consumption of 21 common snack food items, such as potato chips, cookies, and candy. Accounts of the adolescents’ environments were taken from parents/caregivers, friends, school personnel, Geographic Information System sources, and a content analysis of favorite television shows. The factors found to be significantly associated with greater consumption of energy-dense snacks were individual attitudes/behaviors (e.g., snacking while watching television) and characteristics of home/family (e.g., unhealthy food accessibility at home), peers (friends' energy-dense snack food intake), and school (e.g., student snack consumption norms) environments. In total, 25.5% of the variance in adolescents' energy-dense snack food consumption was explained when factors from within each context were examined together. The implications of these results were that if one plans to improve the dietary quality of adolescents’ snack food choices, the following factors need to be addressed: individual; home/family characteristics; peers and school environments.

In this 2018 study, adolescents studying at high schools, trade schools and technical institutes in the Pomerania Province were assessed on their nutritional behaviors by using an anonymous questionnaire that asked for dietary information such as nutritional self-assessment, interests in healthy dietary patterns, type and quantity of food consumed daily, the time of consumption of the last meal of the day, snacking between main meals, frequency and quality of snacks eaten, and sources of dietary knowledge acquisition. Data analysis on the 198 subjects (121 girls: 77 boys) revealed that boys ate dinner and supper significantly more frequently than girls, and chose to eat white bread, dumplings, pasta, milk, red meat, poultry and eggs more often. Snacking was seen in 99% of the study group, although there were three times as many underweight girls as there were boys. In addition, diet regimens were adopted statistically more often by girls (37.5%) compared to boys (6.3%). Bartkowicz and Mironiuk (2018) stated a number of abnormal nutritional behaviors were observed in the study group and calls for workshops and youth training by nutritionists to correct these habits and educate both young people and their parents and legal guardians.

Llanaj et. al (2018) examined food intakes of 289 young students taken from three universities in Albania, to assess their consumption of foods and drinks both at home (AH) and out of home (OH) along with how these relate to nutritional contribution to their daily diet. Through using a single day Automated Multiple Pass Method (AMPM) 24-hour dietary recall, the study assessed the contributions of eating OH to the students’ total energy intake daily and also to consumption of macronutrients. Foods and drinks consumed OH contributed 46.9% of total daily energy intake, representing, on average, 1169.1kcal, although consumption of fruits and vegetables were very low. Out of the house, the more frequently consumed items were sweets, soft drinks and meat products. At home, the average quantity of sugars and dietary fats per day was higher than OH (76.9g vs. 33.7g, 173.7g vs. 142g, respectively). Dietary composition of AH intake was richer in sugars, total fats and proteins, while OH intake consisted of more saturated fats. Although the overall diet appeared unhealthy when nutrients were assessed as energy percentages against WHO proposed nutrient standards for sugar and saturated fats, eating OH was not clearly associated with poor diet quality. The writers believe the data provided can prove useful for designing and conducting future studies and interventions targeting malnutrition in all of its forms.

The objective of this 2020 cross-sectional study was to determine the relationship between students’ eating habits during the school day with sociodemographic, family and physical activity variables, as well as the existence of a cafeteria. A stratified random sample of 8068 students of Public Secondary Education High Schools of Andalusia (Spain) was carried out in this cohort. A number of trends were identified such as: students 14 years old and over were more likely to skip breakfast at home (OR = 0.81) than those under this age; students whose mothers did not have an university education were more likely to consume incomplete breakfast (OR = 0.83); and in schools with a cafeteria, the children were more likely to eat more snacks with sweets (OR = 0.93), candy in general (OR = 2.75), and bagged crisps (OR = 3.06). It was highlighted the factors that significantly influence the eating habits of secondary students in Andalusia include age, sex, parental level of education, physical activity and the existence of a cafeteria.

This 2018 explorative study aimed to qualitatively analyse what U.S. college students perceive as the barriers and enablers that influence healthy eating behaviors. A group of Cornell University students (n = 35) participated in six semi-structured focus groups. With the help of a qualitative software (CAQDAS Nvivo11 Plus), common barriers to healthy eating were identified: time constraints; unhealthy snacking; convenience high-calorie food; stress; high prices of healthy foods; and easy access to junk food. Conversely, enablers to healthy behavior were improved food knowledge and education, meal planning, involvement in food preparation, and being physically active. Parental food behavior and friends' social pressure were considered to have both positive and negative influences on individual dietary habits. Sogari and colleague (2018) point out the importance of consulting college students when developing dietary interventions across the campus as well as considering individual-level factors and socio-ecological aspects in the analysis.

The purpose of this 2019 study was to discover the perceived barriers and enablers of healthy eating in college students (aged 18-24) at the University of Hawai’i at Mānoa. Firstly an interview guide developed based on literature review of relevant studies was successfully tested in a focus group before being applied to the eleven main focus groups conducted in this study. The transcripts of these focus groups were used to identify overarching ideas based on the socio-ecological model of health, consisting of four levels of influence: individual (intrapersonal); social environmental (interpersonal); physical environmental (community settings); and macrosystem (societal). The final results showed the largest barriers to healthy eating according to level of influence in the socio-ecological model were deficiency in nutrition knowledge (individual), peer pressure (social environmental), unsupportive institutional environment (physical environmental), and cost (macrosystem). On the other hand, the largest enablers were nutrition knowledge (individual), parental influence (social environmental), an institutional environment with consistent healthy offerings (physical environmental), and social media (macrosystem). Parental influence was one of several factors that served as both barriers for some and enablers for other participants. Factors such as individual knowledge and parental support were cited as having a positive influence in promoting healthy eating, while the cost of living and food availability at college served as barriers even for motivated students. This research highlighted the areas of study potentially requiring interventions such as nutrition knowledge which may deserve attention to improve upon, reducing cost of food or increasing the healthy options on offer. However, it is still unclear which level of intervention would be most effective in altering eating habits and which barriers/enablers are key deciding factors in determining this population’s food choices.

Johnson et. al (2019) reported the findings of the Colorado Longitudinal Eating and Physical Activity (LEAP) Study, which was an intervention aimed at improving children’s liking and consumption of a target food via repeated exposure and positive experiential learning. There was consistent evidence supporting the use of repeated exposure to improve liking for new foods but Johnson et. al (2019) believes there is not much information on longitudinal effects lasting greater than 6 months. This quasi-experimental study targeted four sites in rural Colorado (2 intervention and 2 control sites) that housed Head Start preschool programs and matched on state vital statistics for childhood obesity rates. A total of 250 children and families took part (41% Hispanic, 69% low-income), with 143 involved in the intervention and the other 107 in the control group. There were 4 time points used in this study: baseline; post-intervention; one-year (Y1) and two-year (Y2) follow ups. The intervention was called “Food Friends - Fun With New Foods”, was delivered by trained preschool teachers, lasted 12-weeks, and focused on positive and repeated experiences with new foods, while a 5-month (1 unit/month) social marketing “booster program” was delivered in kindergarten (one-year follow up) and 1st grade (two-year follow up). The intervention overall was found to be delivered with good fidelity (87%). An increase in liking for the target food was observed for both intervention and control groups over time (p = 0.0001) but the change in intake between baseline and post-intervention was significantly greater in the intervention group compared to the control (p<0.0001). This trend disappeared when intake between baseline and Y2 follow up was compared. The pattern of consumption of the target food was different over time for both intervention and control groups (p<0.005). Moreover, children in the intervention group who liked the target food consumed nearly double their baseline consumption at post-intervention (p < 0.0001) and maintained this increase at Y2 follow up (p < 0.0001). The researchers conclude this study claiming the Food Friends intervention saw larger improvements in children’s eating behaviors than would be expected with developmentally-based changes in dietary behaviors.

One of the objectives of this 2015 cross-sectional study was to examine associations between young adults’ meal routines and practices such as food preparation, meal skipping and eating on the run, with key dietary indicators like consumption of vegetables/fruits, fast food and sugar-sweetened beverages. Another aim for Laska and her team (2015) was to develop indices of protective and risky meal practices most strongly associated with diet. The target group was community college and public university students in the Minneapolis/St. Paul metropolitan area, Minnesota (USA). Among the 1013 students who participated in this study, the meal routines and practices most strongly associated with healthy dietary patterns were related to home food preparation (i.e. preparing meals at home, preparing meals with vegetables) and meal regularity (i.e. routine consumption of evening meals and breakfast). Conversely, the factors most strongly associated with poor dietary patterns included eating on the run, using media while eating and purchasing foods/beverages on campus. A Protective Factors Index, summing selected protective meal routines and practices, was positively associated with fruit/vegetable consumption and negatively associated with fast-food and sugar-sweetened beverage consumption (P<0·001), while a Risky Factors Index revealed significant, positive associations with fast-food and sugar-sweetened beverage consumption (P<0·001). Furthermore, the probability test for the association between the Risky Factors Index and fruit/vegetable intake was P=0·05. Laska and her colleagues (2015) conclude that the young adults’ food choice may have been influenced by the ways in which they structure mealtimes and by their contextual characteristics of eating, suggesting it may be important to consider the context of mealtimes in developing dietary messages and guidelines.

Vilaro et. al (2018) recruited 1149 first-year college students from eight U.S. universities to assess their food choice priorities (FCP) and examine its associations with consumption of fruits and vegetables (FV), fiber, added sugars from non-beverage sources, and sugar-sweetened beverages (SSBs). To help determine the students’ influencing factors in making food choices, the Food Choice Priorities Survey was completed, as well as the NCI Dietary Screener Questionnaire. The research inspected the associations between FCP and dietary intake documented from fall 2015 to spring 2016, controlling for sex, age, race, and BMI. FCP importance changed across the freshmen year and significantly predicted dietary intake. The most important FCP were price, busy daily life and preferences, and healthy aesthetic: both price, and busy daily life and preferences (taste, convenience, routine, ability to feel full) predicted lower FV, higher SSB, and more added sugar while the advertising environment was positively associated with SSB intake; while those who endorsed healthy aesthetic factors (health, effect on physical appearance, freshness/quality/in season) as important in terms of food choice, consumed more FV and fiber and less added sugar and SSB. The analyses indicated that FCP and demographic factors explained between 2%⁻17% of the variance in dietary intake across models and that the strongest relationship was between healthy aesthetic factors and SSB (p < 0.01). Since some FCP fluctuated in importance across the first year of college, it may be possible to design an intervention that shifts the students’ FCP in a way that positively impacts their diet quality.

Wadolowska et. al (2019) aimed to identify nutrition knowledge-related lifestyle (including diet quality, physical activity and screen time) and socioeconomic correlates of skipping breakfast, a school meal, or both and assessed their associations with adiposity markers in Polish teenagers. Using a short form of a food frequency questionnaire the organisers were able to gather data related to the consumption of selected food items and meals, physical activity, screen time, sociodemographic factors and nutritional knowledge from the sample population of 1566 fourth and fifth grade elementary school students aged 11-13. Respondents reported the usual consumption of breakfast (number of days/week) and a meal or any food eaten at school (number of school days/week) labelled as 'a meal at school'. Also taken were the measurements of body weight, height, and waist circumference, where BMI-for-age ≥25 kg/m2 was considered as a marker of overweight/obesity (general adiposity) while waist-to-height ratio ≥0.5 as a marker of central obesity (central adiposity). The results showed that 17.4% of teenagers frequently skipped breakfast (4-7 days/week), 12.9% frequently skipped a meal at school (3-5 school days/week), while 43.6% skipped both of these meals a few times a week. Predictors of skipping breakfast and/or a meal at school included: female gender, age over 12 years old, urban residence, lower family affluence, lower nutritional knowledge, greater screen time, and lower physical activity. Moreover, in comparison to "never-skippers," "frequent breakfast skippers" were more likely to be overweight/obese (odds ratio, OR 1.89; 95% confidence interval, 95%CI 1.38, 2.58) and centrally obese (OR 1.63; 95%CI 1.09, 2.44), while skippers a few times a week of both of these meals were more likely to be overweight/obese (OR 1.37; 95%CI 1.06, 1.78). Wadolowska and her team of researchers (2019) believed special attention should be paid to help shorten the amount of screen time and increase physical activity and nutritional knowledge of teenagers. An estimated 44% of Polish children usually skipped both breakfast and a school meal a few times a week, which were associated with general adiposity and even central adiposity in the case of frequently missing breakfast.

Kelishadi et. al (2017) selected students aged between 6 and 18 via multistage cluster sampling method from rural and urban areas of 30 provinces of Iran, and asked the subjects to complete a validated questionnaire of food behaviors including questions on snacking and taking/skipping meals. The aim was to assess the relationship between snack consumption and meal skipping in these Iranian children and adolescents. From the selected 14,880 students, a total of 13,486 individuals completed the study (90.6% participation rate). Among them, 32.08% skipped breakfast, 8.89% skipped lunch and 10.90% did not have their dinners. Compared to their counterpart groups, the frequency of meal skipping was higher in girls, urban inhabitants, and students in higher school grades (P < 0.05). The findings also demonstrated a positive association in many types of snack groups between snack consumption and incidence of meal skipping. It was found that meal skipping and snack intake were common among iranian children and adolescents, suggesting evidence-based dietary interventions are warranted to improve the students’ eating habits.

In this 2020 study, a total of 14,440 school go-ers aged 7-18 years from 30 different provinces of Iran were assessed to examine the relationship between skipping main meals with fruit and vegetable intake among children and adolescents. This study was conducted in the framework of the fifth survey of a national surveillance program entitled Childhood and Adolescence Surveillance and Prevention of Adult Non-communicable Disease study (CASPIAN- V). The number of students who completed the study was 14,274 (99% participation rate) with the average age of 12.3, varying in gender (50.6% male) and living area (71.3% urban). Statistically significant associations were found between skipping main meals and low fruits and vegetables intake, with skipping breakfast, lunch and dinner all associated with vegetables intake (ORs = 1.19, 1.61, and 1.52, respectively) and fruit consumption (ORs = 5.33, 9.11, and 2.21, respectively). These findings highlight the importance of promoting regular meal consumption along with higher intake of fruits and vegetables in children and adolescents.

The aim of this 2020 study was to determine the association between meal skipping and subjective health complaints among children and adolescents living in Iran. As a part of the fifth national school-based surveillance program (CASPIAN-V) in Iran, a total of 14,400 academics aged between 7-18 years old (mean age 12.3) were selected from 30 Iranian provinces using multistage stratified cluster sampling method. Breakfast was found to be associated with an increase in risk of the following: stomachache (OR = 1.77), backache (OR = 1.68), difficulty getting to sleep (OR = 1.66), feeling nervous (OR = 1.59), and irritability (OR = 1.29). The same pattern was seen in skipping lunch, with greater incidences of stomachache (OR = 1.63), headache (OR = 1.27), backache (OR = 1.58), and also difficulty getting to sleep (OR = 2.07). While dinner skipping was related to 39, 59 and 52% increase in odds of headache, feeling low and difficulty in getting to sleep, respectively, it was associated with decreased odds of stomachache (OR 0.33). Azemati and others (2020) concluded that since meal skipping was associated with some somatic and psychological health complaints among children in this study, regular meal consumption, that is at least three times a day, is highly recommended in this young population.

Since meal skipping is associated with diet-related chronic disease risk and is highly prevalent in young adults, the focus of this 2019 study was to assess individuals aged 18-30 on the prevalence and correlates of meal skipping among this age group. An aggregate of 578 people signed up for this study (24% male, 76% female) and used the real-time smartphone application called “FoodNow” to report their food and beverage consumption over 4 non-consecutive days. The day after each reporting day, participants were asked about their previous day’s eating occasions to confirm any eating occasions not recorded or skipped meals. The information from this application was used to categorise participants into specific meal skippers (breakfast, lunch and/or dinner skipper). The subjects also completed an online questionnaire, which contained measures of correlates from the social-ecological framework across the individual, social-environmental and physical-environment domains. While correlates from the social-environmental and physical-environmental domains of the social-ecological framework were not linked to any meal skipping behaviors, individual domain correlates like time scarcity, education and smoking status were associated with varying meal skipping behaviors. Participants with a university education were less likely to be a meal skipper (any meal) (OR = 0.46; 95%CI: 0.22, 0.95; p = 0.035), while those who previously or currently smoked cigarettes were more likely to be breakfast skippers (OR = 1.10; 95%CI: 1.15, 3.86; p = 0.016) compared to those who had never smoked before. Furthermore, there was an increase in chance for those subjects who noted time scarcity to be breakfast (OR = 1.12; 95%CI: 1.00, 1.26; p = 0.036) or lunch skippers (OR = 1.11; 95% CI: 1.01, 1.23; p = 0.033). No variables were significantly associated with dinner skipping. What these findings told us was that the correlates of meal skipping vary according to the specific meal skipped, university status should be considered when designing interventions with the goal of decreasing the amount of meal skipping among young adults, while correlates such as time management and smoking status may also offer potential behavior change targets within these interventions.

Since there is evidence that learning is positively affected by breakfast consumption in children, Adolphus, Lawton & Dye (2019) focused on examining the associations between habitual school-day breakfast intake frequency with academic performance among British adolescents. School performance was measured by the General Certificate of Secondary Education (GCSE), a national academic qualification obtained by most British children/adolescents during secondary education. The 294 participants aged between 16 and 18 (77.2% female) completed a retrospective 7-day food diary and a questionnaire to obtain data on breakfast intake and on their GCSE grades, respectively. Breakfast was defined as any food or drink containing ≥5% of total energy expenditure (TEE) consumed up to 10:00 a.m. on school days. The frequency of breakfast consumption on a normal habitual week was categorized as rare (0-1 school days), occasional (2-3 school days), or frequent (4-5 school days). The results demonstrated that habitual school-day breakfast consumption amongst adolescents was a significant correlate of GCSE achievement, since those “rare” breakfast consumers had a significantly lower capped score and mean point score when compared to frequent breakfast eaters. Moreover, low/middle socio-economic status (SES) adolescents who rarely consumed breakfast were significantly less likely to achieve higher Mathematics grades compared to low/middle SES adolescents who frequently consumed breakfast [adjusted cumulative odds ratio (OR): 0.35, 95% confidence interval (CI): 0.17-0.72]. The team of researchers believe these findings offer potential and should be further explored in well controlled studies.

With large populations of adolescents imprisoned with limited access to nutritional care and lack of diet required for optimal brain function, Gesch (2013) tested the theory that poor diet may be a modifiable causal factor in antisocial behavior by introducing nutrients in the deficient diets of violent young adult prisoners (aged 18-21 years) and assessing whether it has an impact on behavior. In this double-blind study, the young prisoners were administered either a placebo or a capsule with required daily doses of vitamins, minerals and essential fatty acids. Taking the multinutrient intervention capsule significantly reduced the number of offences committed compared to the placebo group, and after 2 weeks of supplementation, even the number of the most serious offences (including violence) dropped by 37%. Since the Dutch Ministry of Justice has also reported a 48% difference in outcomes in their double-blind study, these results can be replicated and suggests that these supplements provide a simple and humane means to help cut down on violent and antisocial behavior.

This 2017 study used the data from the Mater-University of Queensland Study of Pregnancy (a prospective Australian pre-birth mother-child dyads study) to analyze the association between maltreatment experienced in childhood with high dietary fat consumption in adulthood, and the potentially predictive role of gender-childhood maltreatment interaction in this relationship. The connection between age at which maltreatment was verified, number of childhood maltreatment cases, and high dietary fat intake-related behaviors, were also explored. The 7223 mother-child dyads enrolled in this study were recruited early on in pregnancy, and followed up 3-5 days postpartum and also when the child was 6 months, 5, 14 and 21 years of age. The cases of child maltreatment between the ages 0-14 years were substantiated by agencies. Complete data on dietary fat intake behaviors after 21 years was gathered for 3766 (47.4% female) participants. The results from unadjusted and adjusted analyses showed a link between confirmed childhood maltreatment (including physical abuse) with behaviors related to high fat consumption. Variables significantly related with high dietary fat intake-related behaviors were: being mistreated between the ages 5-14 years; and two or more substantiations of maltreatment. The influence of gender-childhood maltreatment interaction on the size and direction of the association was insubstantial. Future studies should replicate this correlation between chronic and severe forms of childhood maltreatment with a higher rate of dietary fat intake in young adulthood, while possibly exploring neuro-hormonal mechanisms that may explain this behavior.

This 2019 study assessed the relationship between interpersonal violence (family physical violence, body appearance-related bullying and bullying for other reasons), social isolation, and unhealthy weight control practices (self-induced vomiting/taking laxatives and trying any diet pills, powders, or liquids to lose/gain weight/muscle mass without medical advice), based on data from the National School Health Survey (PeNSE, 2015). A total of 102,072 Brazilian adolescents in 9th Grade were recruited from public and private schools. Logistic regression models revealed the correlation between family physical violence and social isolation with increased unhealthy weight control habits in both sexes. Boys who experienced family physical violence were nearly twice as likely to exhibit unhealthy weight control patterns than girls who suffered this same type of violence. Other trends included increased incidence of self-inducing vomiting/taking laxatives (OR 2.29), taking of any diet pills, powders, or liquids to lose (OR 1.92) or gain weight/muscle mass (OR 1.51) among girls who had been bullied based on their body appearance. These associations were stronger than those involving other types of bullying. To summarize, interpersonal violence (family physical violence and bullying) and social isolation were related with a higher chance of practising unhealthy weight control habits.

The purpose of this 2018 study was to find an association between mental health problems, eating behavior patterns, nutrient intakes and health related quality of life (HRQoL) among the 107 Iranian adolescent girls (aged 15-17 years old) signed up from 3 different high schools in Tabriz city, Iran. The dietary information of the adolescents were collected using an Iranian version of the semi-quantitative Food-Frequency Questionnaire (FFQ), while HRQoL, mental health problems and eating behavioral patterns were assessed by adopting the Short Form 36 (SF-36), Strengths and Difficulties Questionnaires (SDQ) and Eating Behavioral Pattern Questionnaire (EBPQ), respectively. The most common mental health problem among this young female sample were indicators of conduct problems (25.2%) and indicators of hyperactivity disorders (18.6%). While hyperactive disorders were prevalent in 35.5% of the studied population. The study also found that the young subjects who scored highly for 'snacking and convenience', 'planning ahead' and 'meal skipping' eating habits were significantly likely to show indicators of emotional disorders (P < 0.05). Moreover, those in the highest tertile for the 'low fat eating' eating pattern were associated with reduced risk of developing hyperactivity disorders (P < 0.05). The prevalence of emotional, conduct, and hyperactivity disorders were all lower among participants who scored highly on the vitality and mental health components of HRQoL. Differences in BMI and nutrient intake between the various categories of mental health problems was determined to be insignificant. The data here suggests that unhealthy eating habits such as 'snacking and convenience', 'planning ahead' and 'meal skipping' positively predict "emotional disorders'' while the "low fat" eating pattern was identified as a negative predictor of hyperactive disorders.

Wickham et al. (2020) set out to find out which one of sleep, physical activity and diet has the strongest influence on mental health and well-being among young adults, and also investigated their higher-order relationships in predictive models. An online survey was designed to measure the respondents’ sleep quality and quantity, physical activity, consumption of raw and processed fruit and vegetables, fast food, sweets, and soda, as well as to collect data on demographics, socioeconomic status, and other covariates. Depressive symptoms and well-being were assessed using the Center for Epidemiological Depression Scale (CES-D) and the Flourishing Scale, respectively. There were 1,111 young adults (28.4% men) from New Zealand and the United States (aged 18-25) who responded to the survey. Among these participants, the strongest predictor of depressive symptoms and well-being was sleep quality, followed by sleep quantity and physical activity, after controlling for covariates. The intake of raw vegetables and fruit was the greatest predictor of well-being but not depressive symptoms. The study also determined several higher-order interactions among health behaviors in predicting the outcomes, but these did not survive cross-validation. These results indicate sleep quality is an important predictor of mental health and well-being among young adults while diet and physical activity have significant influence. Interventions targeted at improving the psychological health and well-being of young adults should consider focusing on sleep quality.

Late eating is associated with obesity, inflammatory markers and circadian-related disturbances in school-aged children