https://orcid.org/0000-0002-7714-8869
Abstract
Introduction
The study aimed to investigate the associations between skipping breakfast and various health risk behaviours and mental health in university students in 28 countries.
Methods
Using a cross-sectional study design, 21,972 university students with a median age of 20 years from 28 countries in Africa, the Americas and Asia, replied to self-reported measures of breakfast consumption, health compromising behaviours, mental health measures and protective factors.
Results
In adjusted logistic regression analysis, infrequent and/or frequent breakfast skipping was associated with inadequate fruit and vegetable intake, frequent soft drink intake, not avoiding fat and cholesterol, current binge drinking, current tobacco use, gambling, not always wearing a seatbelt, inadequate physical activity, inadequate tooth brushing, not seeing a dentist in the past year and having been in a physical fight. In addition, infrequent and/or frequent breakfast skipping was associated with depression, lower happiness, posttraumatic stress disorder, loneliness, short sleep, long sleep, sleep problem, restless sleep, sleep problem due to traumatic event, and poor academic performance.
Discussion
We found evidence that skipping breakfast was associated with 10 of 15 health risk behaviours, all of nine poor mental health indicators and poor academic performance.
Introduction
In the adolescent period lifestyle patterns are developed, including breakfast consumption.Citation1 Skipping breakfast is a common practice among university students, which has been shown in various studies, eg, in Barbados, Grenada and Jamaica, 48.2% of females and 41.6% of males,Citation2 in Bahrain 50%,Citation3 47.7% in Turkey,Citation4 and significantly increases the risk of overweight/obesity, cardio metabolic risk factors, type 2 diabetes and heart disease.Citation5–Citation9 Most studies investigating the association between skipping breakfast and health compromising behaviours and mental health have been conducted with single health risk variables, among adolescents and in high-income countries. There is particularly a lack of studies investigating the effect of skipping breakfast on multiple health risk variables among university students from low- and middle-income countries and across a number of countries, which prompted this study.
Various studies among adolescents or emerging adults found associations between skipping breakfast and overweight/obesity,Citation6,Citation10-Citation15 more negative body perceptionCitation13 and unhealthy dietary behaviour,Citation16 including low fruit and vegetable intake,Citation1,Citation13,Citation16,Citation17 higher sodium intake,Citation16 lower consumption milk/dairy,Citation1,Citation11,Citation16 higher consumption of sweets, sugary or soft drinks,Citation1,Citation13 and skipping other meals.Citation11,Citation13
Mental health correlates of skipping breakfast include stress or mentally distressed,Citation18–Citation20 depressive mood,Citation10,Citation18,Citation21-Citation23 lower happiness scores,Citation24 suicidal behaviour,Citation10,Citation18 shorter sleep duration,Citation1 nocturnal sleeping problems,Citation25 and poor sleep quality.Citation26 Skipping breakfast has among adolescents or emerging adults further been associated with substance use, such as smokingCitation1,Citation12,Citation27 and alcohol use,Citation1,Citation10,Citation12 physical inactivityCitation1,Citation11,Citation15,Citation28 and sedentary behaviour.Citation1,Citation11 Other effects included poor oral hygiene, such as less frequent tooth brushingCitation29 and no dental care visit in the past year,Citation30 and poor hand hygiene, such as no hand washing before meals,Citation29 no seatbelt use,Citation29 cardio metabolic risk factors, such as systolic blood pressure,Citation5 and poorer academic performance.Citation10,Citation15,Citation19 The study aimed to investigate the associations between skipping breakfast and various health compromising behaviours and mental health in university students in 28 countries.
Methods
The cross-sectional study comprised 21,858 college or university students with a median age of 20 years (interquartile range =3 years) with complete breakfast consumption data from 28 countries in Asia: Bangladesh, India, Indonesia, Kyrgyzstan, Laos, Malaysia, Myanmar, Pakistan, Philippines, Russia, Singapore, Thailand, Turkey, and Vietnam; in Africa: Cameroon, Egypt, Ivory Coast, Madagascar, Mauritius, Namibia, Nigeria, South Africa and Tunisia; and the Americas: Barbados, Columbia, Grenada, Jamaica and Venezuela. “In each study country one or two universities were purposefully selected.”Citation31,Citation31,Citation31
In each university, research assistants administered a questionnaire and anthropometric measurements to all students in classrooms selected through a cluster random sample procedure in 2013.
Written informed consent was attained from all participating students, and ethics approvals were obtained from all participating universities (see supplementary file). The study was conducted in accordance with the Declaration of Helsinki. Participation rates were in most countries over 90%.
Measures
Breakfast consumption was measured with the item, “How often do you eat breakfast?” (“Almost every day, sometimes, rarely or never”).Citation32 Skipping breakfast was defined as sometimes, rarely or never having breakfast.
Socio-demographic information comprised gender, age, residence status, subjective wealth status and country income.
Overweight or obesity was determined based on measured body mass index (BMI) and defined as ≥23.0 kg/m2 in South and East Asian countriesCitation33 (WHO, 2004) and ≥25.0 kg/m2 in the other countries.Citation34 “Standing height was measured to the nearest 0.1 cm without shoes, using a stadiometer. Participants, wearing light clothes were weighed to the nearest 0.01 kg on a load-cell-operated digital scale, which was first calibrated using a standard weight and re-checked daily”.Citation2
Fruit and vegetable intake was measured with two questions, 1) “How many servings [80 grams] of fruit do you eat on a typical day?” and 2)”How many servings [80 grams] of vegetables do you eat on a typical day?”Citation35 Inadequate fruit and vegetable intake was defined as “less than 5 servings a day.”Citation36
Other dietary items comprised: 1) “avoiding foods containing fat and cholesterol”, 2) “frequency of eating red meat” 3) adding salt to food (“usually, sometimes, occasionally, never”).Citation36
Binge drinking (past-month) was assessed with the item, “How often do you have (for men) five or more and (for women) four or more drinks on one occasion?”Citation37
Tobacco use was defined as currently using “tobacco products (cigarettes, snuff, chewing tobacco, cigars, etc.).”Citation38
Gambling behaviour was measured with 5 different gambling behaviours, eg, “Played cards for money,” from the “South Oaks Gambling Screen (SOGS).”Citation39 Gambling in the past week was defined as any of the five assessed gambling behaviours once a week or more. (Cronbach alpha 0.78)
Seatbelt use was measured with the item, “When driving or riding in the front seat of a car do you wear a seat belt?” (“1 = all of the time, 2 = some of the time, 3 = never and 4 = I don’t ride in cars”).Citation36
Physical activity was measured using the “International Physical Activity Questionnaire (IPAQ) short form,”Citation40 and physical activity levels were defined following IPAQ guidelines.Citation41
Sedentary behaviour was assessed with one item from the IPAQCitation40 and defined as eight or more hours per day.
Oral health risk behaviour was measured with two items, 1) “Do you brush your teeth? … Twice or more a day, about once a day, less than once a day, and seldom or never.”Citation36 and 2) “How frequently do you go for dental check-ups? … Twice a year, once a year, rarely and never.”Citation42
Having been in a physical fight was defined as one or more times in the past 12 months.Citation43
The “Centres for Epidemiologic Studies Depression Scale (CES-D: Ten items)” measured with 15 or more scores severe depressive symptoms.Citation44 (Cronbach’s alpha = 0.76).
“Post-traumatic stress disorder (PTSD)” was measured with “Breslau’s 7-item screener”.Citation45
Loneliness was defined as most (5–7 days) feeling lonely in the past week.Citation44
Happiness was measured with a four-item “Subjective Happiness Scale (SHS),”Citation46 a score of 13 and above was used to describe high happiness. (Cronbach’s alpha 0.94)
Sleep duration: “On average, how many hours of sleep do you get in a 24 h period?” “Responses were divided into three categories: short sleep (≤6 h), reference category (7–8 h), and long sleep (≥9 h).”Citation24
Sleep quality was assessed with the question, overall in the last 30 days, how much of a problem did you have with sleeping, such as falling asleep, waking up frequently during the night, or waking up too early in the morning? Response options ranged from 1 (none) to 5 (extreme/cannot do),Citation47 Restless sleep. ”Much of the time in the past week, your sleep was restless?” Response option ranged from “1=rarely (<1 day) to 4= most (5–7 days)”. Restless sleep was defined as “much (3–4 days) or most (5–7 days).”Citation44
Sleep problem due to traumatic event. “In your life, have you ever had any experience that was so frightening, horrible, or upsetting that, in the past 30 days you had more trouble than usual falling asleep or staying asleep? (Yes/No)Citation45
Poor academic performance was self-reported as “not satisfactory academic performance.”Citation48
Social support was sourced from three questions of the “Social Support Questionnaire.”Citation49 (Cronbach’s alpha 0.94).
Religiosity was assessed with two dimensions (one item organized religious activity and three items intrinsic religiosity) from the “Duke University Religion Index.”Citation50 (Cronbach’s alpha = 0.80).
Data Analysis
Data analysis was conducted with “STATA software version 15.0 (Stata Corporation, College Station, TX, USA)”. Unadjusted and adjusted logistic regression analyses were used to assess the associations between skipping breakfast categories (sometimes and never or rarely having breakfast), with almost daily having breakfast as reference category, relevant confounders (age, sex, subjective economic status, residence status, country, social support, and religiosity) and dependent variables (15 health risk behaviours, nine poor mental health indicators and academic performance). Due to the clustered nature of the data, country was entered in the survey command. Missing data were excluded from the analysis. P values <0.05 were considered significant.
Results
The sample consisted of 21,972 university students (median age 20 years, interquartile range 3 years), 58.4% were females and 41.6% males, 51.2% rated their economic status as high, 53.9% were living away from parents (on their own or in university residences), 53.9% were residing in low- or lower middle-income countries, 63.8% had high social support, 39.8% high organized religiosity and 33.0% high intrinsic religiosity. In all, 13.8% of university students had rarely or never, 34.2% sometimes and 51.9% had almost every day breakfast (see ).
Table 1 Sample and Breakfast Intake Characteristics
Associations Between Skipping Breakfast and Health Risk Behaviour and Mental Health
In adjusted logistic regression analysis, infrequent and/or frequent breakfast skipping was associated with inadequate fruit and vegetable intake, frequent soft drink intake, not avoiding fat and cholesterol, current binge drinking, current tobacco use, gambling, not always wearing a seatbelt, inadequate physical activity, inadequate tooth brushing, not seeing a dentist in the past year and having been in a physical fight. In addition, infrequent and/or frequent breakfast skipping was associated with depression, lower happiness, PTSD, loneliness, short sleep, long sleep, sleep problem, restless sleep, sleep problem due to traumatic event, and poor academic performance (see and ).
Table 2 Breakfast Consumption and Its Associations with Body Weight and Health Risk Behaviours
Table 3 Breakfast Consumption and Its Associations with Mental Health and Academic Performance
Discussion
In agreement with a number of previous studies,Citation1,Citation10,Citation11,Citation13,Citation15-Citation30 this study found that skipping breakfast increased the likelihood of 11 of 15 health risk behaviours, all of nine poor mental health indicators and poor academic performance. These findings replicate earlier results showing the wide range of possible effects of skipping breakfast on various health risk behaviours and poor mental indicators.Citation16,Citation18,Citation20,Citation29
Possible mechanisms to explain the effects of skipping breakfast on health risk behaviours and mental health, may be that having breakfast assists university students to “function better cognitively and psychosocially.”Citation18,Citation51 University students who had almost daily or daily breakfast tended to make healthier food choices throughout the day, as found in an earlier study among Chinese adolescents.Citation1 Some mechanisms through which breakfast contributes to reducing poor mental health have been proposed.Citation52 For example, after eating breakfast, carbohydrates are converted into glucose which is essential for the formation of tryptophan, a precursor protein for the synthesis of serotonin, which regulates depressive symptoms, irritable mood and cognitive functioning.Citation51–Citation53
This study suggests that skipping breakfast is part of an unhealthy behaviour pattern, including poor mental health, which clusters in the form of multiple risk behaviours.Citation16,Citation29 However, various previous studies found an association between skipping breakfast and overweight or obesity,Citation6,Citation10-Citation15 while this study only found such an association in unadjusted analysis. This study did also not find an association between skipping breakfast and sedentary behaviour and high sodium intake, as this was found in previous investigations.Citation1,Citation11,Citation16
Study Limitations
The study survey was limited to a cross-sectional design, participants attending university and most of the questionnaire administered was by self-report. In order to identify causal associations, further longitudinal research is indicated. It is possible, for example, that students with poor mental health adopt skipping breakfast because of their poor mental health. Skipping breakfast was only assessed with one question and did not include diet quality and information about other meals, and future studies should consider several questions, including diet quality, information about other meals, provide definitions of terminology, such as what constitutes breakfast, and reasons or explanations of skipping breakfast. Further, some health risk behaviours, such as fast food consumption, and poor mental health indicators, such as suicidal behaviour, were not assessed in this investigation and should be included in further research.
Conclusion
This investigation added evidence for a large university population from 28 countries that skipping breakfast was associated with 10 of 15 health risk behaviours, all of nine poor mental health indicators, and poor academic performance. Interventions programmes targeting breakfast consumption in this population should address health risk behaviours and poor mental health linked with skipping breakfast identified in this survey.
Disclosure
The authors report no conflicts of interest for this work.
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