Eating habits and body-weights of students of the university of belgrade, serbia: a cross-sectional study.

The purpose of this survey was to quantify the prevalence of overweight and obesity among a sample of students in Belgrade University, Serbia and to describe their main eating habits. A total of 1,624 questionnaire responses were analyzed (response rate 97.3%). The students were recruited during mandatory annual check-ups in April-June 2009. All subjects completed the questionnaire; height (in cm) and weight (in km) were measured by two physicians. Results were assessed statistically. Almost every fourth male student was overweight. Strikingly, 15% of female students were underweight. Highly-significant difference was found between average body mass index (BMI) of male and female students (F=317.8, p=0.001). Students' BMI did not correlate with average family income or with the frequency of taking breakfast (p=-0.064, p=0.152 for males and p=0.034, p=0.282 for females respectively). There is a growing demand for global health strategies which would encourage healthy body-image and figure; thus, these initiatives should mobilize the society on a national and international level.


INTRODUCTION
Meal habits usually depend on lecture schedules attended by students and availability of food inside or in the vicinity of the university campus. As a result of the expansion in the fast-food market and lack of appropriate food courts, students usually face meal skipping, inadequate variety of foods, and snacking (1). Despite a plethora of publications on habits of university students and their health in the available literature, there has been no evaluation of nutritional status of this population in the Republic of Serbia. The purpose of this study was to quantify the prevalence of overweight and obesity among a sample of students in Belgrade University and to describe their main eating habits. This study is part of a larger analytical investigation among Belgrade University students, which estimated factors associated with quality of life (2). comprised demographic data, social status, place of residence during university schooling, regularity in breakfast-taking, frequency of consumption (meat and coffee), and portion-sizes (fruits and vegetables) consumed daily. One portion of fruit was defined as one medium-sized fruit (such as apple, orange, banana, and pear). One portion of vegetables was defined as ½ cup of raw, cooked, canned, or frozen vegetables. Height (in cm) and weight (in kg) were measured in each participant by two physicians (TG and AP, the first and third author of this artcile) before distributing the questionnaire. Body mass index (BMI) was calculated as the ratio of body mass in kg and the square of height in metre. Division of BMI into four categories was done according to the Centers for Disease Control and Prevention (CDC) guidelines: underweight <18.5, normal weight 18.5 to 24.9, overweight 25 to 29.9, and obese >30.

Data analysis
Differences in analyzed parameters were assessed by using chi-square test and ANOVA. Bonferroni post-hoc test for locating differences between multiple groups was performed. Spearman's correlation coefficient (ρ) was used for investigating the association between the variables.

RESULTS
Basic demographic data were shown elsewhere (2).
Male students were, in average, significantly taller and weighed more than females (BMI 23.4±2.7 and 21.0±2.6 respectively, p<0.001). Mean BMI across genders varied within the normal weight range. According to BMI categories, three-quarters had normal weight (Table 1). Almost every fourth male student was overweight. In contrast, 15% of females were underweight. Obese students were the least common category with prevalence of only 1.5%. Students' BMI did not correlate with average family income or with the frequency of taking breakfast (ρ=-0.064, p=0.152 for males and ρ=0.034, p=0.282 for females respectively). Mean BMI did not differ between those who ate breakfast and those who skipped it (21.8 vs 21.9, F=0.092, p=0.912). In addition, BMI did not differ according to students' residence (with parents/alone/student dormitory, F=1.065, p=0.363). More than half of the students (57.3%) ate their breakfast regularly. Onethird of subjects drank coffee every day, opposed to 27.3% who never drank it. Majority of students (80.1%) ate meat at least two times a week. Half of them ate one portion of fruits and vegetables daily ( Table 2). There were no gender differences between consumption of fruits, vegetables, and meat (χ 2 =11.5, p=0.650).

DISCUSSION
Most of the Belgrade University students were of normal nutritional status. Similar mean BMI was In contrast, striking overall prevalence of underweight among Serbian students was recorded to be 10.6%. Proportion of females who were underweight was even higher (15.3%). Bodily proportions and BMI are certainly subject to emotional and physical well-being (6), which is particularly addressed in concomitant eating disorders (7). Also, university setting may have an important role in weight loss in the young adults as well. Academic pressures and time limits might often prevent students from regular meal consumption, leading to unintentional weight loss. Another possible explanation for such a high prevalence of underweight in female students might be related to eating disorders.
In this study, BMI in students did not differ among diverse place of residence during university schooling, implicating that parental involvement in meal regularity does not have impact upon weight change. On the other hand, individuals who take care of meal frequency on their own, accomplish this in a responsible manner without experiencing dramatic weight losses or gains. Survey by Milosevic et al. (8) revealed that the motives of primary food choice in general population in Serbia are sensory appeal and price. Staple foods in this region include potatoes and meat, usually that of pork. This reflects the prevalence of daily meat consumption by students (40%). Eighty percent of the subjects ate meat at least 2 times a week. Almost half ate two portions of fruits and vegetables daily, which, along with meat, expands the variety of daily food to a satisfactory level. In the Belgrade University, each faculty has its own cafe where students can spend time during the lecture breaks, however, without possibility of taking a proper meal. In our study, more than half of the students ate their breakfast regularly. The importance of taking breakfast was emphasized because of the local circumstance that university schooling schedule covers the period from 8 am to 6 pm. Therefore, it is crucial that students have regular morning meal before the start of daily duties. Additionally, in the Belgrade University, there were no organized lunch breaks between classes. Being the largest urban area of the country, Belgrade has recently been experiencing expansion of the food market that enables students to eat outside the faculty area. Such organization with higher-education facilities (i.e. faculty buildings in the centre of the city) differs, to a great extent, from the isolated campus structure in the USA. Consequently, recent investigation in California, USA (9), has documented a decrease in fruit and vegetable intake after starting college and living on-campus.
Since the students were filling in the questionnaire independently, we may consider reliability of data and potential information as well as recall bias.
Additionally, there were no food intake diaries to quantify exact consumption of the ingredients.

Conclusions
Nutritional interventions among students have already shown positive results (10). Therefore, promotion of healthy food consumption, with abundant fibres, whole grains, dairy products, and low energy-dense foods is needed. In addition, there is a growing demand for global health strategies which would encourage healthy body-image and figure; thus, these initiatives should mobilize the society on a national and international level.