JOURNAL OF FOOD COMPOSITION AND ANALYSIS (2002) 15, 359–365 doi:10.1006/jfca.2002.1075 Available online at http://www.idealibrary.com on
ORIGINAL ARTICLE Changes in Nutrient Intake in the Adult Population of the Slovak Republic K. Babinska´*,1 and A. Be´derova´w *Institute of Physiology, Faculty of Medicine of Comenius University, Sasinkova 2, 813 72 Bratislava, Slovak Republic; and wState Institute for Health, Ruzˇinovska 820 09 Bratislava, Slovak Republic Received September 28, 2001, and in revised form March 8, 2002
Major changes in social and economic conditions occurred in Slovak Republic in the last decade. Since these factors influence food choice to a great extent, changes in nutrient intake of the population were expected. Epidemiological studies focused on dietary habits of the adult Slovak population were conducted in 1991–1994 and 1995–1999. Dietary data were obtained from randomly selected 4018 subjects aged 19–80 years by a single 24-h dietary recall. Calculation of nutrient content was based on Slovak food composition database. Despite a decrease protein and fat intakes still exceed recommendations. Saturated fatty acids prevail; consumption of linoleic acid also approaches the upper limit of recommended values. On the opposite, a-linolenic acid content in food is low. Dietary fibre intake increased; however, it does not meet the recommended dietary allowance. A significant increase in the consumption of calcium, vitamin C and folate, as well as that of copper and vitamin B6 in females was found, however, vitamin and mineral intake is generally lower than the recommendation except that of iron, folate, vitamin A and vitamin E in males. In recent years only slight, but generally desirable changes in food habits of the Slovak r 2002 Elsevier Science Ltd. All rights reserved. population were observed. Key Words: nutrient intake; Slovak population.
INTRODUCTION Nutrition is one of the key factors that influence the health status. The typical dietary pattern of affluent countries is associated with increased morbidity and/or mortality from nutrition-related diseases including cardiovascular diseases, cancer, diabetes osteoporosis and other serious conditions (Hubbard et al., 1994). Food choice, and thus the nutrient content of the diet, is influenced by several factors. Strong determinants of dietary habits include indicators of socio-economic status (Johansson et al., 1999), higher social status being associated with a healthier diet. The early 1990s represented a period of major social and economic changes in Slovak Republic (Statistical Yearbook of Slovak Republic, 2001). It was expected 1 To whom correspondence and reprint requests should be addressed. Tel.: + 421-2-59-357-523. Fax: + 421-2-59-357-515. E-mail:
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that rising living expenses including higher food prices and/or the increase of unemployment rates would have negative consequences on the dietary pattern of the population. Undesirable changes of food habits in a nutritionally vulnerable group of children and adolescents from selected regions of Slovak Republic were observed by Be´derova´ et al. already in 1992 (Be´derova´ et al., 1994). At the same time growing attention focused on diet–health issues was observed in the country. Population was exposed to a more intense health and nutrition education that stressed the importance of healthy diet in the prevention of nutrition-related diseases. One of the aims of an epidemiological survey of dietary habits and nutritional status of the Slovak population was to assess changes in nutrient intake that occurred during the 1990s and to evaluate current nutrient intake in the adult population of the Slovak Republic. The final goal of these studies was to obtain results that would serve as baseline for dietary intervention programmes, educational projects, formulation of nutrition recommendations and guidelines for professionals as well as for the general public. Current pattern and major changes in intake of selected nutrients that are most relevant to the risk of chronic non-communicable diseases are presented in this article. MATERIALS AND METHODS Two epidemiological studies focused on dietary habits and nutritional status of the Slovak population were conducted in 1991–1994 and 1995–1999. The country-wide surveys involved 4018 subjects aged 18–80 years (885 males and 1483 females in 1991–1994, 439 males and 1211 females in 1995–1999). Neither of the studies was designed as a survey representative for the population of the country; however, our aim was to recruit a diverse sample of subjects of different age categories and socioeconomic background. Since practically all institutions in the country have a telephone, schools, enterprises, state institutes, private companies, farms, etc., were randomly selected from a telephone book. Employees or students in the abovementioned institutions were enrolled into the study. Higher age groups were recruited from clubs for the elderly. A high proportion of non-respondents caused the significantly lower number of males in comparison with females, since participation in the study was voluntary. Dietary habits were assessed on the basis of a single 24-h dietary recall method. The data collection included working days as well as weekends and was spread all over the year. Trained dietitians interviewed the subjects and collected detailed information on food items and their quantities consumed during the previous day, where possible food recipes were recorded. Quantities were estimated both in household measures and precise weights. Recalls were checked on quality and completeness and then quantified and coded. Coding was based on the structure of the national food composition database. Leftovers, inedible parts of the food and nutrient losses in food processing were subtracted. Correctness of the edited data was checked. Conversion to nutrients was done by using a self-developed software Nutrition based on the Slovak food composition database compiled by the Food Research Institute (Slovak Food Composition Bank, 1999). Statistical package Statgraphics 4.0 was used for the statistical analyses. Means and standard deviations of the nutrient intake were calculated. Student’s t-test was performed in order to assess the significance of difference of the mean intakes in the two study periods. The most recent version of Slovak Recommended Dietary Allowances (RDA, 1997) was used as a standard for the evaluation of the pattern of nutrient intake.
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RDA for the Slovak population include recommendations for 18 different groups of adults according to gender, age and the level of physical activity. Thus, individuals were ranked into groups corresponding with categories considered in the recommended dietary allowances. For each subject his/her results were compared with recommended dietary allowances for the respective group and per cent of meeting the RDA for selected nutrients was calculated. Subsequently, the average intake for the total groups of males and females was determined. Research was approved by the Ethical Committee of the Ministry of Health of the Slovak Republic.
RESULTS In Table 1 the mean daily nutrient intake of the Slovak adult population in the two study periods (1991–1994 and 1995–1999) is compared. An overview of the mean nutrient intake that was observed in the recent survey (1995–1999) is presented in Figures 1 and 2 as per cent of the RDA. Total protein consumption significantly decreased in females. Only a slight decrease of borderline significance was observed in males. Despite a decrease the current protein intake exceeds RDA by 34.9% in males and 23.1% in females (Fig. 1). A significant decrease (Po0.001) in fat intake was found both in males and females. Fat content of the food still remains higher than the recommendation (Fig. 1), especially in males. A more detailed analysis of fatty acid composition of the diet (Table 2) shows predominance of saturated fatty acids. Proportion of both monoenic and polyenic fatty acids on the total energy content is within the interval of TABLE 1 Comparison of the mean daily nutrient intake in the adult population of the Slovak Republic for the periods 1991–1994 and 1995–1999 (mean, standard deviation and statistical significance of the difference between the two periods) Males Nutrient
Unit
1991–94 Mean
Protein Fat Carbohydrates Dietary fibre Vitamin A Beta-carotene Vitamin B1 Vitamin B2 Vitamin B6 Folate Vitamin C Vitamin E Calcium Iron Zinc Copper
g g g g mg mg mg mg mg mg mg mg mg mg mg mg
s.d
Females
1995–99 Mean
s.d
94.4 32.3 90.6 33.5 115.3 49.1 104.1 52.2 318.0 107 333.4 126 18.0 19.8 21.2 12.2 1.64 1.57 1.37 1.61 2.30 3.60 2.29 3.91 1.18 0.49 1.15 0.47 1.37 0.79 1.31 0.69 1.09 0.52 1.10 0.53 0.20 0.18 0.24 0.18 53.0 45.4 60.6 51.7 15.8 8.2 14.6 9.6 656.7 404.1 824.3 509.1 23.0 9.4 22.7 8.5 11.0 5.1 10.6 5.8 1.84 1.16 1.85 1.76
1991–94 P
Mean
s.d
1995–99 Mean
s.d
0.06 71.2 28.5 67.2 25.4 0.001 86.7 40.1 77.9 35.3 0.05 261.0 96.7 266.1 95.5 0.001 15.1 7.8 16.6 8.6 0.01 1.50 1.50 1.33 1.31 n.s. 2.43 3.48 2.32 2.75 n.s. 0.89 0.39 0.85 0.35 n.s. 1.05 0.64 1.03 0.52 n.s. 0.86 0.42 0.93 0.43 0.001 0.22 0.17 0.22 0.17 0.01 54.2 43.8 70.1 58.9 0.05 12.6 7.8 11.9 7.7 0.001 532.2 341.5 657.6 367.8 n.s. 18.4 8.0 18.6 7.1 n.s. 8.5 4.2 7.72 3.63 n.s. 1.51 1.06 1.63 1.28
P 0.001 0.001 n.s. 0.001 0.01 n.s. 0.01 n.s. 0.001 0.001 0.001 0.05 0.01 n.s. 0.001 0.001
BABINSKA´ AND BE´DEROVA´
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% RDA
200
100
134.9 123.1
126.1 112.8
protein
fat
70
80.1 71.2
70.3
0 carbohydrates males
dietary fibre
females
FIGURE 1. The mean daily intake of energy yielding nutrients and dietary fibre in the adult population of the Slovak Republic (as % of RDA).
89.6 90.2
er
100.4 75.7
nc
91.4
169.6 123.6 zi
n iro
pp co
ca
lc
in ta m vi
79.6
107 86.6
iu m
E
C in ta m
vi
fo
la t
e
6
73.2 88.4
119.5 112.2
57.6 51.7
71.8 69 B in ta m vi
in
B
1 B ta m vi
in ta m
vi
te
be
ta
vi
-c a
ro
ta m
in
ne
A
0
2
75.7 73.2
49.7
38.3
157.6
100
148.5
% RDA
200
males
females
FIGURE 2. The mean intake of selected vitamins, mineral and trace elements in the adult population of the Slovak Republic (as % of RDA).
recommended values (Newton, 1996). The intake of linoleic and a-linolenic acid meets the recommendation. Content of eicosapentaenoic and docosahexaenoic acid in the diet is low. Carbohydrate consumption increased only slightly, the change being statistically significant only in males (Po0.05). A significant (Po0.001) rise in dietary fibre content of the diet was observed, which was more pronounced in males.
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NUTRIENT INTAKE IN THE SLOVAK REPUBLIC TABLE 2
Mean intake of fatty acids in the adult population of the Slovak Republic (as % of the total energy intake) Observed intake
Saturated FA (%) Monoenic FA (%) Polyenic FA (%) Linoleic acid (%) a-Linolenic acid (%) Eicosapentaenoic acid (mg) Docosahexaenoic acid (mg)
Recommended intake
Males
Females
7–10 10–13 7–10 5–10 0.5–1 150–200 150–200
13.2 12.1 8.3 7.1 0.53 50 50
12.8 11.6 9.1 8.8 0.54 20 20
Content of fat-soluble vitamins A and E in the diet decreased (Po0.05) both in males and females. Thus, the mean intake of vitamin E in females fell even deeper below the RDA. Vitamin E consumption in males, as well as that of vitamin A in both sexes remained higher than the recommended value. Consumption of vitamin C significantly increased; however, it did not reach the recommended value. Similarly, a rise in folate consumption was found and the current intake meets the recommended dietary allowance. No significant change in intake of vitamin B1, B2, and B6 was found in males; consumption of vitamin B1 in females slightly, but significantly decreased, on the opposite, that of vitamin B6 increased. In general, current intake of these vitamins is significantly lower than the RDA. Similarly, b-carotene content of the diet remains below the recommendation. No significant change in iron intake was found and the mean value still exceeds the RDA. An increase in consumption of calcium was found; however, a further rise is desirable in order to meet the recommended value. No significant change in the content of zinc and copper in the diet was found in males. Zinc consumption in females significantly decreased, on the opposite, a rise in copper intake was found. DISCUSSION The presented study represents the most extensive nutritional survey that was carried out in recent years in Slovakia; and it provides some insight into the dietary habits of the adult population. A large nutritional survey was performed in 1980s in Slovakia; however, it focused on the nutritional status of the population and did not include dietary assessment (Kajaba, 1985). Comparing time periods 1991–1994 and 1995–1999 slight, but generally desirable changes in intake of several nutrients were found. Similar trends were observed in all age–gender groups. Considering the macronutrient intake shifts towards the recommended dietary allowances occurred including a decrease in protein and fat intake, associated with a rise in consumption of carbohydrates and dietary fibre. The decline in protein consumption was caused mainly by a major decrease in animal protein intake. This corresponds with data from food balance sheets, which show a decrease in intake of milk, meat and eggs (Statistical Yearbook of Slovak Republic, 2001). At the same time, plant protein consumption slightly increased,
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which resulted in a balanced intake from both sources (animal to plant protein ratio 1:1). These results indicate a favourable trend of including more plant food in the diet. The effect of excessive fat intake on the increased risk of serious disorders including cardiovascular diseases, cancer, elevated cholesterol levels and obesity is supported by considerable scientific evidence. In this context, the decrease in total fat intake both in males and females can represent a highly desirable change. Despite this fact, current fat consumption in Slovakia remains excessive and currently 35.5% of the total daily energy in Slovak population is derived from fat. Further decrease of fat intake remains a challenge for the future. The fatty acid composition of diet shows that nutrition recommendations should be directed especially towards a decrease of saturated fatty acids intake. In general, the population is aware that animal fat should be replaced by plant fats and oils, and consumption of monoenic and polyenic fatty acids is, in fact, within the limits of recommended values. The problem is that individual types of plant fats are not sufficiently distinguished by the general public and consequently the intake of individual fatty acids diverges from recommendations. Sunflower oil represents the most popular type of oil, at the same time most spreads that are available in the market are also based on sunflower oil. This contributes to a high proportion of linoleic acid in the diet, on the opposite, the intake of a-linolenic acid is just above the lower limit of recommended values. Thus, the ratio of linoleic acid: a-linolenic acid does not meet the recommended value of 1:4–1:10. This imbalance in n-3 and n-6 is typical of a western type of diet and it is believed to be the cause of a variety of disease symptoms (Newton, 1996). Fatty acids derived from fishFeicosapentaenoic and docosahexaenoic acidFare consumed in very low amounts, since the intake of these food items is rather rare in the Slovak population. Since the data from our first survey do not allow to assess the fatty acid composition of the diet, we had no possibility to follow the trend in fatty acid intake. However, food balance sheets show an increase in per capita consumption of plant fats and oils in recent years (Statistical Yearbook of Slovak Republic, 2001). More pronounced positive changes in macronutrient intake were observed in males; however, current intake in females remains more in conformity with the recommendations. The high intake of vitamin A and relatively satisfactory consumption of vitamin E is probably achieved by fortification of edible fats and oils with these vitamins. The observed decrease in intake of these vitamins may be caused by a decrease of fat consumption. In general, consumption of most of the water-soluble vitamins, as well as that of minerals does not meet the RDA. Their current level of intake does not represent a risk of serious clinical forms of deficiency; on the other hand, even mild deficiencies can lead to impairment of functional status of the body. Moreover, recent studies show that low intake of vitamins is associated with an increased risk of oxidative damage, which is the underlying process of either cardiovascular diseases or cancer (Gey, 1993). Similarly, levels of homocysteine, which is considered a new risk factor of atherosclerosis are influenced by folate, vitamin B6 and B12 (Jacobsen, 1998). According to our data fruit and vegetables that represent an important vitamin source are consumed in insufficient quantities, especially in males in the winter period. An international comparison shows that the nutritional behaviour of the Slovak population is similar to other European countries (Koch and Pokorn, 1999; Koenig and Elmadfa, 1999; Hermann-Kunz and Thamm, 1999).
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The social and economic situation in the country during the planning period of the study indicated that rather undesirable trends in nutrition situation were to be expected; however, our results show the opposite trend. This may be explained by a more stabilized socio-economic situation in the second half of the 1990s, contribution of a marked increase in food choice and nutrition education. It was shown that education and nutritional knowledge may be the most important social predictor for a healthy diet and it may be more closely associated with dietary intake than traditional socio-economic variables, e.g., income (Blaxter, 1990). Results of our surveys served as baseline information for the preparation of the National Healthy Nutrition Promotion Programme that was adopted in the country at the end of the 1990s. A decade represents a relatively short period of time and the observed trends should be interpreted with caution. To confirm the observed trends in nutrient intake further monitoring of dietary habits is required. CONCLUSIONS In recent years only slight, but generally desirable changes in food habits and nutritional status of the Slovak population were observed. Despite these changes the current intake of many nutrients still deviates from the recommended dietary allowances and the food pattern corresponds to a typical Western-type diet with all its possible consequences on the health status. Considering these findings it is necessary to support nutrition intervention plans in the Slovak Republic and to promote healthy life-style into educational projects. Moreover, the rapidly changing food supply requires regular updating of national food composition tables. REFERENCES Be´derova´, A., Babinska´, K., Maga´lova´, T., and Brtkova´, A. (1994). Comparison of selected nutritional indicators in children in Slovakia in 1988 and 1992. Eur. J. Epidemiol. 10, 115 119. Blaxter, M. (1990). Health and Lifestyles. Tavistock/Routledge, London. Gey, K. F. (1993). Prospects for the prevention of free radical disease, regarding cancer and cardiovascular disease. Br. Med. Bull. 49, 679–699. Hermann-Kunz, E. and Thamm, M. (1999). Dietary recommendations and prevailing food and nutrient intakes in Germany. Br. J. Nutr. 81, S61–S69. Hubbard, R. W., Mejia, A., and Horning, M. (1994). The potential of diet to alter disease processes Nutr. Res. 14, 1853–1895. Jacobsen, D. W. (1998). Homocysteine and vitamins in cardiovascular disease. Clin. Chem. 44, 1833–1843. Johansson, L., Thelle, D. S., Solvol, K., Bjorneboe, G. A., and Drevon C. A. (1999). Healthy dietary habits in relation to social determinants and lifestyle factors. Br. J. Nutr. 81, 211–220. Kajaba, I. (1985). Survey of the nutrition situation in changed living conditions. Final Report, Research Institute of Human Nutrition, Bratislava. Koch, V. and Pokorn, D. (1999). Comparison of nutritional habits among various adult age groups in Slovenia. Nutr. Res. 19, 1153–1164. Koenig, J. and Elmadfa, I. (1999). Food-based dietary guidelinesFthe Austrian perspective. Br. J. Nutr. 81, S31–S35. Newton, I. S. (1996). Long chain fatty acids in health and nutrition. J. Food Lipids 3, 233–249. RDA. (1997). Recommended Dietary Allowances for the Population of Slovak Republic. Off. J. Ministry Health Slovak Republic 45, 58–64. Slovak Food Composition Bank (1999). Revision 1999. Food Research Institute, Bratislava. Statistical Yearbook of Slovak Republic (1991–1999) (2001). Editor: SPNFSlovak Pedagogical Press, Bratislava.