Reviews

UDC 371.716:378(100)

Doctor of Medical Sciences A. D. Ignatyev

Study of the Nutritional Status of Students in Different Countries

Department of Food Hygiene, First Moscow Medical Institute named after I. M. Sechenov

As the number of students and their role in society increase, they are being studied ever more intensively from a variety of perspectives, including nutrition. Nutrition can be assessed objectively only by taking into account the physiological characteristics of metabolism, which determine the quantity, quality, and timing of food required; the effects of academic and other demands; living conditions and financial circumstances; health status; beneficial and harmful habits; cultural level and adaptability to life; and the range of foods and dishes available through retail outlets and public catering. An objective assessment also requires establishing a clear relationship between actual food consumption and health status, using the most appropriate indicators. An analysis of the literature available to us—which, incidentally, is quite limited—shows that student nutrition has not been studied in such comprehensive detail in any country.

Most publications on this subject have appeared in the United States (Chalmers et al.; Grindley et al.; Odland et al.; Walters). American researchers study student nutrition from many different perspectives: to optimize retail trade and organize different forms of public catering (Kahn); to identify possible links among nutrition, metabolism (Pittman et al., 1946; Remington and Culp; Tilt), and the development of certain diseases; and to foster sound habits. Three specialized journals covering student nutrition are published in the United States. Yet students have been recognized as a population group requiring an individual approach to nutritional study only since 1947. No marked differences have been found between the diets of students and those of the rest of the population. This is also true of other countries. Given that the diet of the US population deteriorated between 1950 and 1968 (Davis et al., 1969), the unsatisfactory nutritional status of American students is not unexpected (Myers et al.).

In India in 1966, 31,000 students at 512 educational institutions were surveyed by questionnaire (Rao). In 1951–1963, the diets of small groups of students (Ball; Banerjee, 1951, 1962, 1962, 1963; Sarkar; Taylor et al.) and the state of public catering (Rao) were studied in detail. The results were unsatisfactory.

At one university, the diets of 785 students were studied longitudinally over six years (Walker). Mean fluctuations from year to year were ±10%, whereas individual differences were 5–10 times greater. This indicates that such prolonged studies of the same group of people, whose living conditions remain practically unchanged over that period, are of little practical value. One in-depth study is preferable to several fragmentary, superficial ones. It is better to repeat the work after several years to determine the effectiveness of the recommendations made following the initial observation. Our own experience and an analysis of the literature from the USSR and other countries support this conclusion.

There are individual publications on the subject of interest to us from Japan (Kawabata et al.); the Netherlands (Den Haag and Vermey-Scheltema); Norway (Eeg-Larsen and Solumsmoen); Switzerland (Ritzel and Schlettwein-Gsell); Australia (Rogers et al.); Spain (Peña Yañez et al.); Canada (Crampton et al.); Malaysia (Chandra and Bhattathiry); England (Canning and Mayer); the Federal Republic of Germany (Wiss); the German Democratic Republic (Becker; Wirth); Czechoslovakia (Šidlova et al.); Poland (Wilczińska; Krauze et al.; Witkowska); and other countries. Most of these publications are too fragmentary to provide even an approximate picture of the problem as a whole.

The only exceptions are the data concerning Czechoslovakia and Poland. In Czechoslovakia, for example, 10,800 students were surveyed in 1955–1957, representing approximately 53.5% of the total number in Prague (Kopiesczna et al.), as were 916 students in Bratislava (Kukura et al.). In the German Democratic Republic, where 830 students were surveyed (Becker; Wirth), students eat better than those in Poland and Czechoslovakia, but somewhat worse than those in the USSR (A. P. Borisov; V. M. Brabich; R. A. Gdalevich et al.; A. D. Ignatyev et al.; A. K. Koshcheev et al.; V. Stepanovichene et al.; R. Sh. Tagirova et al.; Z. F. Turuk-Pchelina et al.; E. G. Sharina et al.; N. G. Shchepkin and A. F. Legun; and others). Yet there are almost no publications on the practical implementation of the findings. One gains the impression that science and practice in this field are taking separate paths. In Poland, for example, standards for student food service have been developed, but they are not observed.

In France, a special team has been studying student nutrition for the past 10 years. It has concluded that fundamental reforms are needed in this area. Since the principal cause of inadequate nutrition among young people in education is their limited knowledge of hygiene, it has been recommended that a course in food hygiene be introduced in all educational institutions (Kytspotter). As in other countries, food service in France is characterized by meager and monotonous menus, failure to observe food storage and sale periods and food-processing procedures, and so forth. In response, the French government issued a special circular (Tracq and Kytspotter).

The most serious problems concern students’ meal schedules. Young people in education in every country fail to maintain regular meal schedules, and breakfast—the most important meal—is the one most often affected. In Czechoslovakia, for example, this is observed in 61% of students (Kukura et al.); in the USSR, the figure is 31% at the Kaunas Medical Institute, and at the Perm Medical Institute it is 52% among fourth-year students and 25% among first-year students. Medical students eat not better but worse than students at other higher education institutions. In Vilnius, for example, 20% of students eat twice or even once a day.

In the United States, more than 50% of students skip breakfast at least once a week, and 30% do so twice or more (Dunkerley and Kramer). This is also characteristic of the country’s population as a whole, with adolescents most frequently failing to maintain regular meal schedules. They bring this harmful habit with them to college. Women, who, owing to their bodies’ tendency toward obesity, should eat more frequently, eat less often than men.

The reasons for skipping breakfast and disrupting meal schedules in general are highly varied (Haseba and Brown), but the chief among them is the students’ own lack of discipline and their disregard of elementary hygienic principles of proper eating. At the same time, their breakfasts are often biologically inadequate. It is therefore not surprising that, one to two hours after breakfast, more than half of students begin to feel hungry (Harris), and their capacity for work declines (Tuttle et al., 1951, 1960). Since opportunities for a snack are not always available at college, the sensation of hunger becomes dulled and students’ bodies adapt to later but heavier meals, after which their capacity for work falls still further.

Breakfast is a key issue in the provision of adequate nutrition for students and needs to be addressed nationwide, taking local conditions into account.

An optimal breakfast, after which hunger is not felt for 6 hours, provides 700–800 kcal, 25–35 g of protein, 30 g of fat, and 100 g of carbohydrates (Addison et al.; Daum et al.; Thornton and Horvath). The younger the person, the more substantial the breakfast should be; conversely, the older the person, the less substantial it should be. Even so, two breakfasts are preferable to one, however optimal.

The daily allocation of time and energy is approximately the same among students in all countries, with about 70% of the day spent in physical inactivity (L. S. Kadzyauskene; Walker). Over the past 40 years, for example, energy expenditure among medical students in Moscow has changed by only 10% (A. P. Borisov; N. G. Shchepkin and A. F. Legun). Nutritional standards, however, have changed several times over this period and differ from country to country. This points to deficiencies in the setting of nutritional standards, which in turn reduces the objectivity of conclusions about the true physiological adequacy of actual dietary intake.

Comparison of data reported by different authors is greatly complicated by the wide variation in students’ ages (from 15 to 37 years) and body weights. Overall, however, students do not suffer from obesity. Excess weight, for example, was found in 2.4% of American students (Pargman), but in 20–30% of adolescents in the United States (Hammer). It is caused not by excessive food intake, since students of limited means also suffer from obesity (Canning and Mayer), but by insufficient physical activity (Johnson et al.), which reduces energy expenditure.

Differences in basal metabolism associated with local climatic conditions are more pronounced. It is therefore inappropriate to compare the diets of students in countries with cool and hot climates. In a warm climate, basal metabolism is lower (Remington and Culp; Tilt; Young and Donelsen; Young et al.), and consequently the need for food is lower. Moreover, metabolic rates are lower in summer than in winter (Pittman et al., 1943, 1946), and individual variation is ±20% (Banerjee et al.). This must be regarded as normal, with a differentiated approach guided by local nutritional standards.

In light of the foregoing, we present for comparison a series of figures characterizing the actual diets of young people in education. The energy value of the diets of students in different U.S. states during 1932–1962 was 2,670–3,040 kcal for men and 1,700–3,699 kcal for women (Davis and Scoular; McCord; Myers et al.; Odland et al.; Scoular and Foster; Young et al.); in Japan it was 2,530 and 2,200 kcal, respectively (Kawahata), and in South Africa 2,780 and 1,900 kcal, respectively (Walker), with variation of ±10% over all the years of observation. Day-to-day fluctuations are greater than week-to-week fluctuations. The energy value of the daily diets of male and female students in Czechoslovakia is 2,844 and 2,235 kcal, respectively (Kopieszna and Vanečkova); in the GDR, 3,031 and 2,300 kcal (Wirth; Becker); in India, 2,000–1,500 kcal (Banerjee, 1962); and in Vilnius, 2,905 and 2,346 kcal, respectively (L. S. Kadzyauskene).

Protein intake among male and female students in the United States is 150 and 113 g, respectively (Bricker et al.; McKay et al.; Schuck; Scoular et al., 1957); in Czechoslovakia, 100 and 77 g; in the GDR, 98 and 53 g; and in India, 50 and 40 g (Banerjee et al., 1962, 1963; Nirmala et al.). In Vilnius the corresponding figures are 73 and 57 g, and in Kazan, 75 and 97 g per day (R. Sh. Tagirova et al., 1969).

Male and female students in the United States consume 133 and 153 g of fat, respectively, including 53 and 55 g of vegetable fat; those who engage in sports consume 230 g. In India the figures are 62 and 31 g, and in the GDR, 220 and 63 g. Male and female students in Vilnius consume 131 and 101 g of fat and 337 and 284 g of carbohydrates, respectively. Consumption by male and

Carbohydrate intake among male and female students is 330 and 218 g in South Africa, 400 and 303 g in Czechoslovakia, and 662 and 265 g in the GDR; in India it is 249 and 157 g per day.

Vitamin C intake among students is 71–102 mg in the United States (Dunkerley and Kramer; Scoular and Foster; Young and Donelsen), 50 mg in India (Banerjee; Nageswara), 47–209 mg in the GDR (Wirth), 60 mg in Switzerland (Ritzel and Schlettwein-Gsell), and 20–31 mg in Czechoslovakia (Šidlova et al.). In Vilnius, vitamin C intake is 50 mg among male students and 37 mg among female students. Vitamin A intake is 5,351–10,798 IU in the United States, 5,000 IU in Switzerland, 4,588 IU in the GDR, excluding β-carotene (Becker), and 5,089 IU in India (Banerjee et al., 1963). In Vilnius, vitamin A intake is 1.7 mg among male students and 1.2 mg among female students, or 5,000 and 4,000 IU, respectively. Vitamin B₁ intake is 1–2.8 mg in the United States (Henshaw et al.), 1.2 mg in Switzerland, 0.8–4.0 mg in the GDR (Wirth), and 0.66–1.86 mg (0.29–1.13 mg) in Australia (Rogers et al.). Riboflavin intake is 1.7–2.7 mg in the United States, 0.3–2.9 mg in the GDR, 2.4 mg in India, 1.6 mg in Switzerland, and, in Vilnius, 1.5 mg among male students and 1.1 mg among female students.

Calcium intake is 717–1,496 mg in the United States (Myers et al.), 264–1,919 mg in Australia, 550 ± 31 mg in India (Nageswara Rao), 352–1,215 mg in the GDR, 323–346 mg in Czechoslovakia (Šidlova et al.), and, in the USSR, 290–738 mg in Kazan (R. F. Tagirova et al.) and 652 mg among male students and 492 mg per day among female students in Vilnius. All these figures exclude calcium consumed in water. Phosphorus intake is 700–1,453 mg in the United States (McKay et al.), 2,280 ± 88 mg in India, 635–2,350 mg in the GDR, 420–1,800 mg in Australia (Dale), and, in the USSR, 1,024–1,700 mg in Kazan and 1,362 mg among male students and 1,039 mg among female students in Vilnius. Potassium intake in Poland is 3,020 mg (Witkowska); iron intake is 6.6–13.6 mg in the United States (Holt and Scoular; White), 16.6 ± 2.2 mg in India (Nageswara Rao), 5–22 mg in the GDR, and 8.4–23.4 mg per day in Australia.

The literature, however, provides very little specific information on consumption of the foods through which students obtain these nutrients. For example, meat products are consumed by 90–100% of students in the United States and the Netherlands (Den Haag et al.; Myers et al.; Seshadri and Harill; Young, 1946); in the GDR, students consume 0–179 g of meat products, while in India they eat almost none. In Vilnius, meat products are consumed in sufficient quantities and are predominantly fatty. Fish products are consumed by 80–90% of students in the United States (Balley et al.); in the GDR, consumption is 0–57 g, while in India students eat almost no fish. American students eat eggs in 90% of cases (Balley et al.). In the GDR, consumption ranges from 0 to 1.4 eggs per student, and students at Leiden University eat eggs almost every day (Den Haag et al.). Students in India eat almost no eggs. Cheese and cottage cheese are consumed by students in the United States in 80–100% of cases, in quantities of 25–80 g; in the GDR, consumption of these products ranges from 0 to 104 g. Milk is consumed by students in the United States in 90–100% of cases, in quantities of 750 ml (Anonimouse, 1963; Stasch et al.); consumption is 0–775 ml in the GDR, 500 ml in the Netherlands (Den Haag et al.), and 100–500 ml per day in India.

It should be noted that 30–50% of students in Asia cannot tolerate milk, which is an uncommon food in their diets (Davis A. et al., 1967). Milk intolerance is also observed among students in other countries. The figures are 10.6% in Spain (Peña Yañez et al.), 5% in the United States (Bayless et al.), and 6.5% in Europe as a whole (Stasch et al.). Bread consumption among students in the GDR ranges from 19 to 343 g. No more than 70% of students in the United States consume pasta, whereas in other countries, particularly Italy and Japan (Kawahata) and India, it is consumed in large quantities. In the GDR, pasta consumption among students ranges from 0 to 109 g. According to data from the United States, students consume 10–30 g of butter (Myers et al.); according to GDR data, consumption is 0–74 g.

Potato consumption in the German Democratic Republic is 21–429 g, and consumption of other vegetables is 7–443 g; in the United States, potato consumption is 120–170 g, and consumption of other vegetables is 113–115 g cooked and 57–113 g raw (Myers et al.). Students in India consume particularly large quantities of vegetables and legumes (Nageswara Rao), since most are vegetarians out of necessity (Seshadri and Harill). Fresh and preserved fruit is never available in the Oslo student cafeteria (Eeg-Larsen and Solumsmoen).

Students’ choice of foods depends on various factors—health, habits, availability of money and free time, and so on (Hein). Men eat twice as much as women (Den Haag and Vermey-Scheltema), are less particular about food, and prefer hot dishes to cold ones (Anonymous, 1966). On weekends they eat more than usual (Becker); students living in dormitories eat less well than those living at home (Kawabata).

The state of student food services has received very little attention in the literature. Most publications are from the United States. All cafeterias in that country operate on a self-service basis and serve up to 10,000 students or more per day (Pridenaux and Shugart). They are equipped with automated serving lines, receive centrally supplied convenience foods and partially prepared frozen meals (Jones), make extensive use of computers (Tavis), and so on. Nevertheless, as the Americans themselves acknowledge, food services do not meet present-day requirements. There is a shortage of experienced cooks and dietitians. Cafeterias organize social evenings, banquets, and beauty contests, along with lectures and talks, film screenings, and television programs on the principles of sound nutrition. They also hold countryside picnics and sporting competitions, create a pleasant atmosphere in dining halls, set up counters for ordering food packages, add dietitians to their staffs, and so forth. There is, however, no uniform approach to menu planning: one-day, weekly, and two-week menus are used. Nor are there general guidelines for food-service establishments.

In Poland, inspections of student food services revealed inadequate compliance with sanitary and food-preparation standards, as well as discrepancies between the meals actually served, the prescribed menus and recipes, and physiological nutritional requirements (Wilczińska; Krauze et al.; Witkowska; Bulinski and Glowniak). In Czechoslovakia, a survey found that 70% of students were satisfied with the quantity of food, but only 40% with its quality (Kukura et al.). Certain shortcomings have also been noted in the diets of Soviet students—in Kaunas (V. Steponavičienė et al.) and in Perm, Leningrad, and Kazan (R. M. Tagirova et al., 1969).

In many countries, nutrition is further impaired by factors such as excessive consumption of coffee, cocoa, and alcohol; smoking; and examination-related and other stresses (Ball; Lipman and Mueller; Scrimshaw et al.). Students’ poor knowledge of food hygiene must also be noted (Alpert and Bitzer; Gormican and Dickie; Gyorgy; Kintzer; Sabine; Stasch et al.).

There are almost no studies on the effects of nutrition on students’ health and academic performance. Poor nutrition has been associated with rapid fatigue among students (Luhanova), reduced visual perception (Anonymous, 1968), increased incidence of dental caries—which affects approximately 95% of students—and disturbances of cholesterol metabolism (Cagánová et al.; Davis; Luhanova; Kasl et al.), among other effects.

Overall, student nutrition is a serious problem in every country; it can be successfully addressed only on a nationwide scale. The time has come to move from collecting and collating facts to seeking and testing new approaches and reviving effective older methods of sound nutrition. This is essential for the successful implementation of the Resolution of the Central Committee of the CPSU and the Council of Ministers of the USSR “On Measures to Further Improve the Material, Housing, and Living Conditions of Students at Higher and Specialized Secondary Educational Institutions.”

References

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Received June 30, 1973.