3.6.1 Changes in Dietary Patterns
As previously noted, emerging nations experience a dramatic transition in diet and other lifestyle behaviors due to increased industrialization, urbanization, economic development, and market globalization. These processes of modernization and eco- nomic transition ultimately result in an improved standard of living. However, the shift from the traditional to a more Westernized diet may also have produced significant negative consequences in China. Age-group-specific dietary information from the 2002 China National Nutrition Survey is not available at the time of this writing; however, we can examine the overall population trends of dietary patterns among adults (which have recently become available) to help provide some update on changes relevant for older Chinese (see Table 3.2). Figure 3.7 demonstrates changes in the intake of meat, poultry, and seafood from 1982 to 2002, as observed from three national nutrition surveys. The average intake of meat and poultry increased 68%
and more than 200% for urban and rural areas, respectively, over the past 30 years.
The intake of seafood doubled in urban areas and tripled in rural areas during the same period. In contrast, total energy intake from grain sources decreased steadily in both urban and rural areas, from 70 and 80% of total daily energy intake in 1982 to 47% and 61% in 2002, respectively (Fig. 3.8a). Meanwhile, energy consumption from fat increased 32% in both urban and rural areas of China (Fig. 3.8b). Specifically, in 2002, fat accounted for more than 35% of total calories in urban areas, reaching up to 38% of total kcal in large cities like Beijing and Shanghai.
Fifteen years ago, Popkin et al.(9) reported strong evidence that the dietary pattern of the Chinese population was rapidly changing toward the typical high-fat,
Table 3.2
Intakes (g/day) by food group in China for the years 1982, 1992, and 2002
1982 1992 2002
Grains 509.7 439.9 402.1
Dry bean 8.9 3.3 4.2
Bean products 4.5 7.9 11.8
Vegetables 316.1 310.3 276.2
Fruits 37.4 49.2 45.0
Nuts 2.2 3.1 3.8
Meat 34.2 58.9 78.6
Milk and its products 8.1 14.9 45.0
Egg and its products 7.3 16.0 23.7
Fish and other seafood 11.1 27.5 29.6
Cooking oil 12.9 22.4 32.9
Animal fat 5.3 7.1 8.7
Salt 12.7 13.9 12.0
Source: 1982, 1992, and 2002 China National Nutrition Survey.
Chapter 3/ Global Graying, Nutrition, and Disease Prevention 41
high-sugar diet of the West. The authors also indicated that higher income levels, particularly in urban areas, were associated with consumption of such a diet and the ensuing problem of obesity. Even today, there remains a large differential in animal food/fat intake between urban and rural populations and across regions of varying levels of economic development. However, as economic improvements proliferate and reach more rural areas, the predictions by Popkin et al.(9)can increasingly be applied to rural populations. Indeed, rural regions have begun following the trend of their urban peers in the transition of dietary and disease patterns.
3.6.2 Changes in Disease Patterns and Prevalences
As already emphasized, diet-related diseases (e.g., obesity, T2D, CHD, hyperten- sion, stroke, and certain cancers) are significant causes of disability and premature death in both developing and newly developed countries(10). In China, as in many other emerging countries, such diseases are replacing more traditional public health concerns such as malnutrition and infectious disease. This phenomenon has been widely demonstrated in Western societies and is likely to occur in many emerging countries, including China, as they continue to gain economic strength (11).
Although nutritional deficiency and infectious diseases have not been eradicated, these conditions are now largely confined to certain economic and age groups within particular regions of the country.
The overall mortality in China has declined from 20 per thousand in the early 1950s to 6.8 per thousand in 2006(12). Communicable diseases that caused about
62 101 104
22 44 45
23 38
70
7 19 24 0
20 40 60 80 100 120
g/day
Meat & Poultry Seafood Meat & Poultry Seafood 1982 1992 2002
Urban Rural
Fig. 3.7. Meat, poultry, and seafood intake in urban and rural areas.
Source:
For 2002 data: from 2002 national nutrition survey:Yang XG, Zhei F. Diet and Nutrition intake (Chinese). Beijing, China: People’s Publishing House; 2005(30).
For 1992 data: from 1992 national nutrition survey:Ge K. Editor, The Dietary and Nutritional Status of Chinese Population: 1992 National Nutritional Survey. People’s Medical Publishing House, Beijing China, 1996.
For 1982 data:Report on 1982 National Nutritional Survey. Institute of Nutrition and Food Hygiene, Chinese Academy of Preventive Medicine. Institute document, 1986.
42 Wang and Bales
8% of deaths in 1957 have been largely reduced, while chronic diseases are now considered a major cause of death. A large, international collaborative study found heart disease (23%), cancer (22%), and cerebrovascular (21%) diseases to top the list of the leading causes of death for the total population of China. Pneumonia and influenza (3.2%), infectious disease (3.1%), accidents (2.8%), COPD (1.8%), chronic liver disease (1.5%), diabetes (1.5%), and kidney disease (1.4%) rounded out the list of causes of mortality(13).
3.6.2.1 OBESITY
Dietary energy and fat intakes are known to be positively and significantly associated with body mass index (BMI: note that Asian BMI criteria are overweight¼OW : BMI
70
57.4 47.4
80 71.7
60.7
0 10 20 30 40 50 60 70 80 90
%
Urban Rural
1982 1992 2002
25 28.4
35.4
14.3 18.6
27.7
0 10 20 30 40
(b) (a)
%
Urban Rural
1982 1992 2002
Fig. 3.8. a: Percent of energy intake from grains: 1982, 1992 and 2002.b:Percent of energy intake from fat: 1982, 1992 and 2002.
Source:
For 2002 data: from 2002 national nutrition survey:Yang XG, Zhei F. Diet and Nutrition intake (Chinese). Beijing, China: People’s Publishing House; 2005(30).
For 1992 data: from 1992 national nutrition survey:Ge K. Editor, The Dietary and Nutritional Status of Chinese Population: 1992 National Nutritional Survey. People’s Medical Publishing House, Beijing China, 1996.
For 1982 data:Report on 1982 National Nutritional Survey. Institute of Nutrition and Food Hygiene, Chinese Academy of Preventive Medicine. Institute document, 1986.
Chapter 3/ Global Graying, Nutrition, and Disease Prevention 43
24.0–27.9 and obesity¼OB : BMI >28.0) in the Chinese population. Although the prevalence is still much lower in China than in Western societies and other developing countries, a 10 year increase of 84% and 38%, for OW and OB, respectively (Fig. 3.9), is a potential forerunner of OB-associated chronic diseases and a subsequent public health burden(14,15). Rates of OW/OB are generally higher in urban than rural areas, but Zhang et al.(16)recently reported an 18.6% prevalence of OW in a rural Chinese population. Zhao et al. used the third (2002) National Health Services Survey to assess direct medical costs attributable to OW/OB in Mainland China and estimated the figure to be about 21.11 billion Yuan (approximately US $2.74 billion)(17).
3.6.2.2 HYPERTENSION
Hypertension, a major risk factor for stroke, accounts for 11.7% of the total mortality in the Chinese population and does not vary substantially by gender, extent of urbanization, or geographic region(13). The prevalence of hypertension has been increasing in China in recent decades, whereas rates of awareness, treat- ment, and control remain unacceptably low (18). Figure 3.10 shows that the prevalence of hypertension has increased 3.5 times from 1959 to 2002 in a steady fashion. Considering the large total population of the country, this increase has already created a huge burden for public health and with especially immense effects in the older population.
3.6.2.3 TYPE2 DIABETES(T2D)
In recent years, the prevalence of T2D, which is closely associated with high-risk dietary behaviors and OW/OB issues, has spread nationwide; this is particularly true in the urban population. In the last review of T2D prevalence, we reported an increase by fivefold between 1995 and 1982(19). The overall prevalence of T2D in China is now at an all time high, with increases of 39 and 15% reported for large and middle-sized Chinese urban cities, respectively, between 1996 and 2002 (Fig. 3.11)(20).
12.8
17.5
3.1
5.7
0 5 10 15 20
%
Overweight Obesity
1992 2002
Fig. 3.9. Percentage of overweight and obese Chinese: 1992 and 2002.
Source: China National Nutrition and Health Survey: 1992 and 2002.
44 Wang and Bales
3.7 RAPID GROWTH OF THE ELDERLY POPULATION IN CHINA