Objectives: To assess weight status, eating practices and nutritional knowledge amongst nursing students at the University of Fort Hare, Eastern Cape.

Method: A cross-sectional descriptive survey was conducted on 161 undergraduate (51 male and 110 female) students of the Department of Nursing Sciences at the University of Fort Hare. Body mass index, waist and hip circumferences and waist hip ratio were determined. Nutritional knowledge and eating practices were investigated by structured interviewer-administered questionnaires.

Results: Statically, 49.7% were overweight or obese (58.2% of the females; 31.4% of the males) and 65.2% had waist circumferences putting them at risk for non-communicable diseases. Most did not meet the recommendations for intakes from the vegetable group (97.5% ate <3 servings per day), the fruit group (42.2% ate <2 servings per day), and the dairy group (92.6% ate <2 servings per day); whilst 78.3% ate ≥4 serving per day of sugar or sweets. Most consumed margarine, oil or fat (68.3%), sugar (59.0%) and bread (55.9%) daily, but few reported daily intakes of vegetables (12.4%), fruit (23.6%), fruit juice (21.2%) and milk (15.6%). Fewer than 50% knew the recommended intakes for vegetables, fruit, dairy, starchy foods and meat or meat alternatives.

Conclusions: These nursing students had a high prevalence of overweight and obesity, poor eating habits and inadequate knowledge on key nutrition issues, which may impact negatively on their efficacy as future health ambassadors to the public.

Contexte: Les travailleurs de la santé doivent être équipés pour faire face à l’augmentation de l’obésité et de la morbidité liée à l’obésité dans les pays en développement.

Objectifs: Évaluer le statut pondéral, les pratiques alimentaires et les connaissances en matière de nutrition des étudiants en sciences infirmières à l’Université de Fort Hare, Cap oriental.

Méthode: Une enquête transversale descriptive a été réalisée auprès de 161 étudiants de premier cycle (51 hommes et 110 femmes) du département des sciences infirmières à l’Université de Fort Hare. L’indice de masse corporelle, le tour de taille et de hanches et le rapport taille-hanche ont été déterminés. Les connaissances en matière de nutrition et les pratiques alimentaires ont été examinées à partir de questionnaires administrés par un enquêteur.

Résultats: Statistiquement, 49.7% étaient en surpoids ou obèses (58.2% des femmes ; 31.4% des hommes) et 65.2% avaient un tour de taille augmentant le risque de souffrir de maladies non contagieuses. La plupart ne respectent pas les recommandations en termes d’apports alimentaires provenant du groupe alimentaire des légumes (97.5% mangeaient moins de 3 portions par jour), du groupe alimentaire des fruits (42.2% mangeaient moins de 2 portions par jour), et du groupe alimentaire des produits laitiers (92.6% mangeaient moins de 2 portions par jour); alors que 78.3% mangeaient 4 portions par jour de sucre ou de bonbons ou plus. La plupart consommaient de la margarine, de l’huile ou de la graisse (68.3%), du sucre (59.0%) et du pain (55.9%) tous les jours, mais moins de 50% mentionnaient un apport en légumes, fruits, produits laitiers, féculents et viande ou substituts de viande.

Conclusions: Ces étudiants en sciences infirmières présentaient un taux de prévalence de surpoids et d’obésité élevé, de mauvaises habitudes alimentaires et une méconnaissance des points nutritionnels clés.

The etiology of obesity involves a complex interplay between genetics and environmental or lifestyle factors.^{7, 8} Eating practices associated with the global obesity epidemic include increased consumption of energy-dense, but nutrient-poor foods;^{7, 9} low consumption of dairy products¹⁰, fruits and vegetables⁹, skipping breakfast¹¹; and insufficient physical activity.^7,8 South Africa, like other developing countries, has been undergoing a transition from traditional high fibre, low fat diets, to typical Western diets that are high in fat, sodium and added sugars, and low in unrefined carbohydrate, dairy, fruits and vegetables; and from traditionally more active lifestyles, to more sedentary practices.^{1, 12, 13} These trends have been associated with the high prevalence of obesity amongst Black South African people, particularly women living in urban areas.^{3, 12, 13}

Studies have shown that counselling interventions are effective in reducing risk and burden of disease in adults with hyperlipidemia and other risk factors for cardiovascular diseases.¹⁴ Since the public views primary care providers as valuable sources of nutritional guidance and lifestyle advice to prevent and treat NCD, health care professionals play a key role in this regard through patient education.^15,16,17 However, studies identify significant barriers which prevent health care workers from offering dietary support; these include lack of time, of teaching materials, of nutritional knowledge and of confidence, on the part of the provider.^18,19 Moreover, it seems from a recent systematic review, that health care professionals are more likely to discuss weight, diet and lifestyle issues with their patients and use strategies to prevent obesity in patients, if they themselves have a normal BMI.²⁰ No published studies to date have addressed these issues amongst South African health care professionals.

The baseline information gathered in this study may highlight knowledge, attitude or practice gaps which need to be addressed in order to empower nurses towards efficient diet and lifestyle counselling in South Africa.

Structured interviews with the participants were performed by the main researcher, who had been trained in nutrition at the University of the Free State. Interviews were conducted in a room at the Department of Nursing Sciences of the University at Fort Hare, and food photos and packaging were used to assist participants in recalling portion sizes and food choices. Eating practices were established by 24-hour recalls obtained during structured interviews with the participants. As a single 24-hour recall does not adequately represent usual food intake, three recalls (for Tuesdays, Thursdays and Saturdays) were recorded for each participant, and the average daily intakes were calculated. The United States Agricultural Department’s Food Guide Pyramid 1992 (USAD-FGP)²² was used to evaluate the food intake, as this tool is familiar to South African students in health care, and quantifies the recommended daily number of portions to be consumed from each food group (as opposed to the South African Food-Based Dietary Guidelines [SAFBDG]²³). The Dietary Guidelines for Americans 2010²⁴ was also used to interpret fat and sugar intakes (not included in the USDA-FGP 1992). Average daily energy intakes were quantified from the data collected in the 24-hour recalls, using a standard exchange list based on the recommendations of the American Dietetic Association²⁵, with portion sizes quantified from the South African Medical Research Council’s (MRC) Food Composition Tables²⁶ and the SA MRC Food Quantity Tables.²⁷ During the same interview, a food frequency questionnaire, which was adapted to reflect food choices of students and used to determine how often a particular food was consumed, was also administered.

Nutritional knowledge was recorded during structured interviews with the participants in their language of choice, using a questionnaire based on the recommendations of the USDA-FGP²², the Dietary Guidelines for Americans 2010²⁴ and the SAFBDG.²³ Questions were asked regarding the food group to be eaten most frequently; the food group to be eaten the least; recommended number of daily servings from each food group; foods with high fat, sugar and fibre content; foods with low fat, sugar and fibre content; and foods high in vitamin C and beta carotene. Students who had an overall score of more than 50% on the knowledge questionnaire were regarded as knowledgeable, whilst individuals who scored less than 50% were regarded as less knowledgeable. Students were also asked to identify their sources of nutritional information – be it their parents, their friends, the media or a school or institution of learning.

Most participants reported that they consumed margarine, oil or fat (68.3%), sugar (59.0%) and bread (55.9%) daily, but few consumed vegetables (12.4%), fruit (23.6%), fruit juice (21.2%), and dairy or dairy products (15.6%) on a daily basis (Table 4). A large number (77.0%) of the participants did not consume low fat or skim milk. Most participants (73.9%) reported not using any alcohol and less than one per cent reported daily consumption of alcohol (Table 4). Self-reported alcohol intakes (Table 3) of most participants (98.8%) were within the prudent guidelines of two or fewer drinks per day.²⁸

Almost two-thirds of the participants (65.4%) had an overall score of more than 50% on the nutritional knowledge questionnaire and were classified as knowledgeable, whilst 34.6% of the participants had an overall score of less than 50% and were classified as not knowledgeable.

Most participants listed the media (47.8%) and school or institution of teaching (35.4%) as their sources of nutritional information. Parents (13.7%) and friends (22.9%) did not rank high as sources of information.

Significantly more overweight or obese (25%), than normal weight (12.2%), participants consumed full cream milk on a daily basis [95% CI: -24.7%;-0.4%]. On the other hand, more underweight participants (57.1%) than both overweight or obese participants (15%) [95% CI: 8.7%; 69.9%], and normal weight participants (16.2%) [95% CI: 7.3%; 68.8%] consumed low fat or skim milk on a daily basis.

Participants with adequate nutritional knowledge (who scored ≥50% on the knowledge questionnaire) did not eat significantly different from those with inadequate nutritional knowledge (who scored <50) regarding any of the food items listed (Table 4).

In contrast, the percentages of overweight or obesity reported in this study were higher than those reported for Black participants at other South African universities in the past. For example, Morar et al.³¹ reported a prevalence of overweight or obesity of 24.3% for Black medical students at the University of Natal. Cilliers et al.³² reported a prevalence of overweight or obesity of 24.7% in Black first-year students at the University of Stellenbosch; whilst the prevalence of overweight or obesity amongst first-year female students was 25% at the University of Limpopo (Turfloop Campus) in 2000.³³

Overweight or obesity figures of the Black nursing students in the current study are however similar to statistics reported for students at universities or colleges in North America^34,35 (where similar statistics have also been reported amongst graduate health care professionals²⁰), but was higher than those reported for some other developing countries in the Middle East³⁶ and Asia.³⁷ This might indicate that the problem of overweight or obesity amongst Black students in South Africa is escalating, possibly due to rapid urbanisation and nutrition and lifestyle transitions to Western patterns.

In the current study, two-thirds of the nursing students (65.2%) had waist circumferences that put them at risk for insulin resistance and the metabolic syndrome according to the guidelines of the New Joint Classification for the Diagnosis of Metabolic Syndrome.⁵ Moreover, 38.5% of the participants had a waist circumference indicating substantial risk for NCD (≥102cm for males; ≥88cm for females).⁴ The high levels of truncal obesity in these participants was also confirmed by 37.3% of participants who had waist-hip-ratios indicative of increased health risk (≥0.9 for males; ≥0.8 for females). These figures are similar to the 42% reported by the SADHS 1998³⁸ (using waist-hip-ratio cut-off points of ≥0.9 for males; ≥0.8 for females); and higher than what was reported by the SADHS 2003 (but which used higher waist-hip-ratio cut-off points of ≥1.0 for males; ≥0.85 for females) for Black men (5.1%) and women (31.7%).³

Quantification of the 24-hour recalls revealed quite low energy intakes, which in the light of the levels of overweight or obesity in this group, raised suspicions that the ’flat-slope syndrome’ – which refers to the phenomenon that participants with high actual consumptions often underestimate the amount of food and drink they recall²¹ – may have occurred; and/or may reflect low activity levels (which were not assessed in this study). Analysis of the 24-hour recalls of these predominantly Black nursing students, according to the food groups on the USDA-FGP, revealed low intakes of vegetables, fruit and dairy, which is characteristic of the nutritional transition reported by numerous studies amongst urbanised Black South African communities.^1,12 These signs of nutritional transition were also evident from the food frequency questionnaires obtained from this group: most participants consumed margarine, oil or fat and sugar on a daily basis, whilst few consumed vegetables, fruit, fruit juice and milk on a daily basis. Interestingly, most of the participants were from rural areas (42.2%) or townships (37.3%) and resided at the university hostels. The fact that they were living on campus may have contributed to fast-track the nutrition transition.

Vegetables and fruits are sources of vitamins, minerals, fibre and numerous phytochemicals which offer protection against NCD, including cardiovascular disease, type 2 diabetes and cancer, by various mechanisms which include acting as anti-oxidants that scavenge free radicals, enhancing the performance of the liver detoxification enzyme systems, and suppressing cancer cell initiation and/or proliferation.³⁹ The finding that only 2.5% of these participants ate at least three vegetables daily, that almost half the participants (42.2%) did not eat at least two portions of fruit or fruit juice per day, and that the overall frequency of the intake of vegetables and fruits was very low, therefore poses a serious health risk. The nutritional knowledge questionnaire revealed that most of the participants also did not know the daily recommended number of servings that should be consumed from the vegetable and fruit groups. Nutritional knowledge is believed to play an important role in promoting healthier eating practices, and increased knowledge of dietary guidelines has been positively linked to more healthy eating practices amongst college students.⁴⁰

Osteoporosis is another chronic disease risk posed by the fact that 92.6% of the participants consumed less than two servings of milk or dairy products per day, whilst only 15.8% indicated that they consume milk daily. Once again, the nutritional knowledge questionnaire revealed that most participants (60.2%) did not know how much milk or dairy products they ought to consume. The prevalence of osteoporosis is on the rise in SA – even amongst the Black population who is less prone to low bone density than Whites and Asians.⁴¹ The majority of the participants in the current study were in their twenties and had not reached peak bone density (at around 30 years) yet. Reaching an optimum peak bone density is considered one of the best ways to counteract the early onset of osteoporosis, and consuming adequate amounts of milk or dairy products is considered the most practical, effective and relatively inexpensive (when compared to the cost of supplements) way to acquire adequate calcium to optimise bone density.⁴² As the majority of the participants were Black South Africans, a high level of lactose intolerance may be expected amongst them.⁴³ However, amongst South African Black persons, the use of fermented buttermilk, such as amazi which contains low levels of lactose, is part of the traditional eating habits.⁴³ When students in a recent study (2010 – as yet unpublished results) amongst students on the University of the Free State (where 55% of students were Black students in 2010), were however asked to rank their preferences for foods that they would buy if available and affordable on campus, amazi and other traditional foods were ranked surprisingly low. This may confirm that the food preferences of Black South African students at University are westernised. A recent study confirmed a decrease in calcium intake with urbanisation amongst Black woman in the North West Province of South Africa.⁴¹ Weight-bearing exercise and other osteoprotective factors were not assessed in the current study.

Both the 24-hour recalls and the food frequency questionnaires pointed out high intakes of fat and sugar or sweets, although most participants were knowledgeable about the fact that these foods should be consumed sparingly. A practical way of cutting back on total and saturated fat intake is by substituting full cream milk with low fat or skim milk, however 76.5% of the participants reported that they do not use low fat or skim milk. Some significant associations could also be shown between higher fat and sugar intake in the overweight or obese participants compared to normal and/or underweight participants.

Self-reported alcohol intakes (Table 3) were within prudent guidelines.²⁷ Most participants (73%) reported not using any alcohol and less than 1% reported daily consumption of alcohol. This is in contrast with reports of high alcohol consumption amongst university or college students in South Africa (2010 – yet unpublished study amongst students at the University of the Free State) and abroad⁴⁴yet underreporting is a possibility.

However, knowledge of good eating habits and a healthy lifestyle is not necessarily enough to motivate health care professionals to practice what they (ought to) preach. Creating an environment that is supportive of healthy eating habits and an active lifestyle, as well as requiring health care students to show competence at applying these principles in their own lives, may go a long way towards achieving this aim. Future research should be directed at finding the most appropriate ways in which to create such structures for different student populations in different cultural settings. This would at least empower the future health care professionals to take charge of their own health, which may increase their efficacy in dealing with nutrition, health and weight issues in their patients.

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