Nutrition in Chinese-Korean Children and Adolescents*

2016-09-21YINXiaoJianXUYaTaoJILiuandJIChengYe

Biomedical and Environmental Sciences 2016年1期

YIN Xiao Jian， XU Ya Tao， JI Liu， and JI Cheng Ye

1. Key Laboratory of Adolescent Health Assessment and Exercise Intervention， Ministry of Education， College of Physical Education & Health， East China Normal University， Shanghai 200241， China； 2. Institute of Child and Adolescent Health， Peking University Health Science Center， Beijing 100191， China

Original Article

Nutrition in Chinese-Korean Children and Adolescents*

YIN Xiao Jian1，#， XU Ya Tao1， JI Liu1， and JI Cheng Ye2

Abstract

Objective To study the nutrition habits among Chinese-Korean children and adolescents in Yanbian Autonomous Prefecture， Jilin， China.

Methods Data were obtained from the Chinese National Survey on Students' Constitution and Health in 1995， 2000， 2005， and 2010 for Chinese-Korean children and adolescents aged 7-18 years. The number of the subjects included was 4789， 4704， 5875， and 5315， respectively.

Results The rate of the occurrence of stunting showed a declining trend from 1995 to 2010 （for boys：urban， 6.3%； rural， 12.7% in 1995 and 3.5% for both in 2010. For girls： urban， 7.8%； rural， 13.4% in 1995 and 4.2% and 5.5%， respectively， in 2010）. Although the ratio of wasting did not show significant differences between the urban and rural children and adolescents in 1995， 2000， 2005， and 2010 respectively， the ratio of occurrence of overweight or obesity increased （for boys： urban， 7.3% and 1.3% in 1995， 17.6% and 12.9% in 2010； rural， 7.0% and 1.3% in 1995， 14.6% and 12.8% in 2010， respectively. For girls： urban， 8.1% and 1.0% in 1995， 17.3% and 8.6% in 2010； rural 5.7% and 0.7% in 1995， 16.4% and 7.4% in 2010， respectively）.

Conclusion The ratio of malnutrition in children and adolescents in Chinese-Korean areas declined from 1995 to 2010， and the distinction in malnutrition between the urban and rural areas was negligible in 2010. Further， the ratio of overweight and obesity increased over this period.

Chinese-Korean children and adolescents； Nutrition； Stunting/Wasting； Overweight/Obesity

INTRODUCTION

C hildhood is a critical period of physical development， during which nutrition plays a very important role in the growth and development of children and adolescents， as nutrition constitutes the most important foundation of physical growth［1］. People of Chinese-Korean ethnicity live mainly in the Northeastern provinces，such as Heilongjiang， Liaoning， and Jilin， among which the population in Yanbian Korean Autonomous Prefecture is the largest， accounting for 97.1% of all people of Chinese-Korean ethnicity in China. The Chinese-Korean ethnicity originates from the Korean Peninsula， including the Democratic People's Republic of Korea （DPRK） and the Republic of Korea. From the mid-19th century to the early 20th century， many Koreans immigrated to China in order to escape from the chaos caused by the war （Figure 1）［2］. Although people of Korean ethnicity can speak the same language and have a similar ancestry as the Chinese people［3］， they live in different countries and have different lifestyles. Therefore， we believe that the physical characteristics of people ofChinese-Korean ethnicity differ from those of people from the DPRK and the Republic of Korea. The Chinese-Korean ethnicity is distinguished from Han ethnicity in terms of the lifestyle involved unique customs， and social and economic conditions. Therefore， to improve the nutrition of children and adolescents， promote the physical health， and improve the quality of life of the population， it is important to understand the nutritional conditions of these populations and identify their present nutritional problems.

Although several studies have reported the nutritional status of children and adolescents in Korea， they mainly focused on people of the Republic of Korea and the Chinese-Korean minority. In addition， a few studies aimed at exploring children's malnutrition in the DPRK［4-6］. Studies on the nutritional status of children and adolescents in the Republic of Korea chiefly focused on cross-sectional studies， many of which were on overweight and obesity rates［7-8］. Many studies reported that the number of overweight and obese children and adolescents had dramatically increased in the Republic of Korea. The prevalence of childhood obesity doubled from 5.4% in 1998 to 10.8% in 2008 in the Republic of Korea， although this figure was still lower than that in Western countries［7-8］. Some studies showed that overweight and obesity in Korean children and adolescents were related to the consumption of high-energy food［9］and poor physical activity［10］. Other studies argued that overweight or obesity in children were associated with other socio-economic factors［11-12］. Lee G et al.［11］reported that obesity in girls was associated with their mothers' long working hours， because long working hours can influence the health of the workers' families. Moreover， Kang HT et al.［12］indicated that low socio-economic status such as low parental education is a risk factor for childhood obesity.

A few studies have previously reported on malnutrition in children and adolescents in DPRK. Katona-Apte J et al.［4］noted that the overall prevalence of stunting and wasting was 38.2% and 16.5%， respectively， and that boys had a higher prevalence of both than girls among children and adolescents in the DPRK. Hoffman DJ et al.［5］showed that the prevalence of stunting and wasting was 39.4% and 8.2%， respectively. Although the prevalence of wasting decreased from 16.5% （1997） to 8.2% （2002）， the prevalence of stunting did not show a significant change in those years （38.2 vs. 39.4%）. Therefore， we concluded that acute undernutrition was decreasing in the DPRK， but chronic undernutrition that resulted in stunting was still highly prevalent. The latest 2012 report on the nutrition status in the DPRK［6］showed that malnutrition and mortality rates among children in the DPRK had improved. However， the prevalence of stunting was still at a moderate-severe level and the regional deviation had increased.

The previous studies that aimed to determine the nutritional status of Chinese-Korean children and adolescents were mainly cross-sectional studies. Many studies indicated that Chinese-Korean children and adolescents had a higher prevalence of overweight and obesity and were shorter and heavier than the Han children in other areas of China. In a sample of 1697 school-aged students， Fang JN et al.［13］reported that in all age groups， regardless of sex， Chinese-Korean children and adolescents were shorter than Han children， but the prevalence of overweight and obesity among Chinese-Korean girls aged 7-18 years was higher than that of Han girls of the same age group. In a study of 1682 （boys， 503；girls， 1179） Korean college students and 2239 （boys，906； girls， 1333） Han college students aged 20 years，Jin YJ et al.［14］found that students of Korean ethnicity were shorter and heavier than those of Han ethnicity. Xiong NN et al.［15］showed that both Chinese-Korean children and adolescents， including boys and girls aged 7-18 years， had a higher prevalence of overweight and obesity than those of Han children. Some longitudinal studies comparedthe status of Chinese-Korean children's growth and development by analyzing the data derived from the students' health testing in 1985 and 2005， but most studies focused only on the physical development and did not compare these values with the average in China and international standards ［e.g.， World Health Organization （WHO） standard］. Dong ZF et al.［16］showed that in a span of 20 years， the average growth rate of height， weight， and bust size of students of Chinese-Korean ethnicity aged 7-18 years and Inner Mongolia increased： the peak height velocity of the Chinese-Korean students in 2005 was higher than that in 1985， but the peak chest velocity of students in 2005 was lower than that in 1985. Li CY et al.［17］found that within 20 years， 3 morphological indices （height， weight， and bust） that are indicative of Chinese-Korean students' physical form and development in Yanbian of Jilin province tended to increase.

Although previous studies from China reported that Chinese-Korean children had shorter height and higher prevalence of overweight and obesity than Han children， most of these studies were cross-sectional. Further， no studies have thus far assessed the status of both malnutrition and overnutrition simultaneously among Chinese-Korean children and adolescents. Therefore， the purpose of this longitudinal study was to examine the nutritional status of Chinese-Korean children and adolescents in China and compare the values with the WHO growth references.

METHODS

Subject and Sampling

In the years 1995， 2000， 2005， and 2010， 4 rounds of the Chinese National Survey on Students' Constitution and Health （CNSSCH） were carried out separately and data were collected. This study could be regarded as the greatest nationwide representative sample of Chinese school-aged children and adolescents. Since 1985 many national government departments such as the Ministry of Education， National Health， Family Planning Commission of the People's Republic of China， the Ministry of Science and Technology， and the State of National Affairs have managed the CNSSCH every 6 years . The target groups of the CNSSCH were mainly divided into 2 categories： 1） Chinese Han students aged 7-22 years， from primary schools， secondary schools， and universities and 2） Chinese ethnic students aged 7-18 years， from primary and secondary schools［18-21］.

The subjects of this study were Chinese-Korean students aged 7-18 years， from primary and middle schools in Jilin province. The research was conducted in the Yanbian Korean Autonomous Prefecture， Jilin province. To ensure the effectiveness and comparability of the research， the following inclusion criteria were applied［22］： 1） The Chinese-Korean students should have lived in Yanbian Korean Autonomous Prefecture for a long time， and 2） the Chinese-Korean students' parents and grandparents should have been of Korean ethnicity. Subsequently，we randomly selected 4789 students in 1995 （2392 boys and 2397 girls）， 4704 students in 2000 （2349 boys and 2355 girls）， 5875 students in 2005 （2876 boys and 2999 girls）， and 5315 students in 2010 （2680 boys and 2635 girls）. The data for this research were provided by Peking University and approved by the Medical Ethics Committee of Peking University. All students' names were digitally coded to avoid leaking of personal information.

Methods of Measurement

All participants underwent a medical examination before testing to exclude those who were physically or mentally disabled. The equipment for measuring height and weight were standardized，and all the experimenters were trained for the anthropometric method of measurement for 1 week. All the tests were conducted according to the standardized program using the unified equipments. All the participants were required to urinate fully and defecate before the test； boys wore only underwear， and girls wore a T-shirt and thin trousers. None of the participants wore shoes during the tests［22］. For the height measurement， the subjects were required to stand up straight on the measuring device with bare feet， and the test result was recorded to 0.1 cm. For weight measurements， the subjects were also required to stand barefoot， and the test result was recorded to 0.1 kg.

Analytic Method

Evaluation Criteria for Nutrition This study was based on the 2007 report of the WHO's Child Growth development standard［23］and examined the presence of malnutrition and overnutrition among Chinese-Korean children and adolescents of different ages. The study regarded stunting and wasting as indices of malnutrition， and overweight and obesityas overnutrition. For evaluation of stunting， we used height-for-age screening （when the height was below the 3rd percentile， it was defined as stunting）；for wasting， overweight， and obesity， we adopted BMI-for-age screening ［when the body mass index （BMI） was minus 2Z-Score， it was considered as wasting， above or equal to 1Z-Score， as overweight，and above 2Z-Score， as obesity］［23］. BMI was calculated as weight （kg）/height （m）2. We evaluated malnutrition according to the values of stunting and wasting obtained in the study from two aspects. On the one hand， we measured the stunting ratios by the height-for-age criterion of the WHO， on the other hand， we could base our calculation of wasting ratios on the BMI-for-age criterion of the WHO，regardless of the stunting group.

Statistical Analysis We used a t-test to separately assess each subject's physical indices （height， weight， and BMI） in urban and rural areas within 15 years （from 1995 to 2010）. We also compared the subjects' residency （urban and rural）in 2010 and 1995. Subsequently， we used a with the chi-square test to inspect the prevalence of malnutrition （stunting and wasting） and overnourishment （overweight and obesity） in urban and rural areas in 1995 and 2010. The 3rd， 50th， and 97th percentiles of height-for-age， and the minus 2Z-Score， M（0）Z-Score， and 1Z-Score of BMI-for-age were computed using the LMS［24］method for Chinese-Korean children and adolescents aged 7-18 years. The level of statistical significance was set at 0.05， and all analyses were conducted using the SPSS version 15.0 statistical software. Data input was performed using the Epidata 3.1 software.

RESULTS

The average height， weight， and BMI of boys and girls of all age groups showed a gradual increase over time among Chinese-Korean children and adolescents aged 7-18 year （Tables 1 and 2）. Among boys， significant differences were noted between rural and urban children and adolescents in 1995 for the following age groups and parameters： height in subjects aged 7 and 10-14 years， weight in subjects aged 7 and 10-13 years， and BMI in subjects aged 9，11， and 16 years； however， no such significant difference was noted between rural and urban children and adolescents in 2010 （except for height aged 10-11）. On the other hand， all physical indices （except height in urban boys aged 18 and BMI in rural boys aged 16 and 17 years） were significantly different between urban areas and rural areas in 2010 and 1995 （Table 1）. Among girls， we found significant differences （height for subjects aged 7-9，12， and 13 years， weight for subjects aged 7-9 and 13 years， and BMI for subjects aged 9 years） between rural and urban children and adolescents in 1995. However， there were no significant differences （except for height in subjects aged 7 years， weight in subjects aged 7 and 16 years， BMI in subjects aged 7，8， and 16 years） between rural and urban children and adolescents in 2010 （Table 2）.

During 1995-2010， the rates of stunting for both boys and girls seemed to decline gradually； however，the ratios of wasting did not show significant differences over time （Tables 3 and 4）. Among boys，the rate of stunting showed a significant difference between rural and urban children and adolescents in 1995 （total stunting rate： urban， 6.3%； rural， 12.7%），but this difference was not seen in 2010 （total stunting rate： urban， 3.5%； rural， 3.5%）. Similarly，there were significant differences （except for subjects aged 15， 16， and 18 years） between rural children and adolescents in 1995 and 2010， but no such significant differences were noted between urban children and adolescents in 1995 and 2010 （except for the 12-year age group）（Table 3）. Among girls， the rates of stunting were significantly different between rural and urban children and adolescents in 1995 （total stunting rate： urban 7.8%； rural 13.4%），but there was no significant difference in 2010 （total stunting rate： urban， 4.2%； rural， 5.5%）. Similarly，there were significant differences between rural children and adolescents in 1995 and 2010 （except for subjects aged 8， 14， 16， and 17 years）， but no significant differences between urban children and adolescents in 1995 and 2010 （except for 7， 10， and 17 years）（Table 4）.

During 1995-2010， regardless of sex or rural and urban areas， the ratio of overweight and obesity increased steadily （Tables 5 and 6）. Among boys， a significant difference in the rate of obesity between rural and urban children and adolescents was found in both 2000 and 2005 （total rate of obesity in 2000：urban， 3.1%； rural， 1.6% and total rate of obesity in 2005： urban， 8.6%， rural， 5.8%）. Similarly， there were significant differences in 1995 and 2010 between children and adolescents in urban as well as rural areas （Table 5）. Among girls， there was no significant difference in the rate of obesity （except for subjects aged 8 and 17 years in 1995， 8 years in 2000， 10 years in 2005， and 9 years in 2010） between rural and urban children and adolescents. In contrast， a significant difference in the rate of obesity was seen in 1995 and 2010 among urban children and adolescents， as well as in 1995 and 2010 among rural children and adolescents （Table 6）.

Figures 2-5 present the 3rd， 50th， and 97th percentiles of height-for-age for ethnical Chinese-Korean children and adolescents from 1995 to 2010， according to the 3rd （the WHO stunting standard）， 50th， and 97th percentiles of the WHO data. Compared with data in 1995， 2000， 2005，figures 2-5 showed that the differences in height between urban and rural children and adolescents declined gradually in 2010， regardless of sex and age. Nearly all the percentiles of boys below the ages of 14-15 years and girls below the ages 13-14 years were close to the WHO reference indexes of height in 1995 and 2000. However， the abovementioned values were higher than the WHO reference indices of height in 2005 and 2010. Moreover， among older subjects （boys，＞14-15 years； girls， above ＞13-14 years）， these values gradually deviated from the WHO reference indexes， and at the higher percentiles， this gap increased.

Figures 6-9 show the minus 2Z-Score，M（0）Z-Score， and 1Z-Score of BMI-for-age of ethnically Chinese-Korean children and adolescents from 1995 to 2010， according to the of WHO standards for minus 2Z-Score （the WHO wasting standard）， M（0）Z-Score， and 1Z-Score （the WHO overweight standard）. Except for data of 1995， when the minus 2Z-Scores of rural boys were below the WHO wasting standards， data of all years showed that minus 2Z-Scores of Korean rural-urban children and adolescents were nearly consistent with the WHO wasting standards. Compared with the data of 1995， 2000， and 2005， regardless of sex and urban or rural setting， the M（0）Z-Score and 1Z-Score of BMI-for-age of Chinese-Korean children and adolescents in 2010 were higher than those of the WHO BMI-for-age.

DISCUSSION

The Yanbian Korean Autonomous Prefecture， a minority region， is located in the east of Jilin province， close to the boundary of China and North Korea. Its capital city is Yanji. With a total area of 43，474 square kilometers and a population of 2，170，000 （2010）， Yanbian is the largest area where Korean people gather in China， among which people of the Korean ethnicity account for 39% （those of the Han ethnicity accounts for 59%）. Yanbian is also located in the Changbai mountainous region，wherein people of the Korean ethnicity account for 54.8% of the population in this region. This region receives 2150-2480 hours of sunshine annually. Its average annual rainfall is 400-650 mm， and its average temperature is 2-6 °C （lowest temperature，-23 °C to -34 °C and highest temperature， 34-38 °C）. People of Chinese-Korean ethnicity mainly consume rice and millet， but their diet also includes beef， dog meat， fish， eggs， milk， and sea products［25］.

The results of this study indicated the following：1） The height and weight of Chinese-Korean children and adolescents gradually increased over time， and the physical differences between urban and rural children were waning. 2） Irrespective of the areas （rural or urban）， the rate of malnutrition among Chinese-Korean children and adolescents （mainly stunting） had decreased， and the difference in the malnutrition status （mainly wasting） between the urban and rural populations was negligible. Many studies showed that inheritance as well as nutritional and socio-economic factors， which are usually reflected by a family's income and parents' educational background， affected children's growth and development. Family income influenced the ability to purchase healthy items， which in turn affects growth in children： A poor family was much more likely to buy a large amount of cheap，unhealthy food to feed their children， rather than a small amount of nutritious food， owing to which， the children were malnourished. This inadequate dietary habit stunted children's growth［26-27］. Furthermore，many poor families might not be able to afford necessary health care services［28-29］. Many studies have shown that parental education had a profound influence on children's physical growth［30-35］. Children whose parents had a high level of education have better physiques than those whose parents had a low level of education［36-38］. Further， parents with a high level of education had resources to promote the health of their children and were in a better position to prevent or alleviate disease. Moreover， parents with a high level of education may have a higher standard of living and healthier behaviors， which directly influenced their children's growth. Maternal education showed a strong association with child care and thus affected children's development［39-40］. In this study， data were obtained from a cross-sectional survey. Therefore，ethnical Chinese-Korean children and adolescents aged 7-18 years in 1995， 2000， 2005， and 2010 were from 4 respective birth cohorts groups for the followingperiods： 1977-1988， 1982-1993， 1987-1998， and 1992-2003. Yanbian Korean Autonomous Prefecture，a minority area， has been highly valued and supported by the Chinese central government. The central government has consistently provided special help from fund investment to policy support， which has resulted in the swift development of the economy and improvement in people's standard of living in Yanbian Korean Autonomous Prefecture. In 1978， the household income per capita of Yanbian was343.4 RMB in urban areas and113.6 RMB in rural areas. In 2010， this value increased to17，469 RMB and7867 RMB， respectively. Further， the urban family income per capita in 2010 was 50.2 times that in 1978， and 69.3 times that of rural family income per capita. This difference decreased from 3.02 times in 1978 to 2.2 times in 2010［41］. It showed Chinese-Korean people in Yanbian rural areas had a better life. With China's reforms taking a greater hold， people's educational level in Yanbian Korean Autonomous Prefecture has greatly increased. The number of college students increased from 4483 in 1991 to 17，856 in 2010. Therefore， with the continuous development of society and economy in Yanbian Korean Autonomous Prefecture，the rural-urban disparities seem to be disappearing. Children and adolescents in Yanbian are growing stronger and taller， and the ratio of malnutrition （mainly stunting） has gradually decreased. At the same time， the urban-rural setting differences in terms of physical condition and malnutrition have also decreased. These findings are consistent with those of previous studies［42-43］. 3） Regardless of the setting （urban or rural）， the ratio of overweight and obesity between Chinese-Korean children and adolescents increased to a higher level. Many studies showed that， with continuous development of the Chinese social economy， the incidence of overweight and obesity between children and adolescents is increasing［44-45］. In a developing country， such as China， children with a high socio-economic status in urban areas were more likely to be overweight and obese than those in rural areas. In contrast， in developed countries， children with a low socio-economic status were more likely to be overweight and obese［46-48］. Wang Youfa previously provided possible explanations for these difference in the socio-economic status［49］. Lifestyles such as diet， acquiring knowledge about health， and physical activity may have an effect on obesity in developed and developing countries such as the US and China， respectively. For instance， in terms of food-consumption patterns， the richer people in China could easily access meat and other energy-dense foods［50］. Several studies found that Chinese-Korean children and adolescents had a higher occurrence of overweight and obese than a similarly aged Han group'［51-53］. Jin XC et al.［54］indicated that one of the reasons for this high risk was that Chinese Koreans had a higher rate of smoking and drinking than Hans in the rural area of Yanbian. Han CJ et al.［55］believed that people of the Korean ethnicity had some unique living habits such as favoring high-calorie and high-fat foods like beef and dog meat， and consuming high-salt foods and refined carbohydrates， which might explain why the prevalence of obesity in Chinese-Koreans is higher than that of Hans. Furthermore， Piao HL et al.［56］showed that compared with those of the Han ethnicity， people of the Chinese-Korean ethnicity preferred the static way of living such as sitting with their legs crossed， and they undertook less physical activities， both of which could lead to the accumulation of subcutaneous fat and consequently increase the rate of overweight and obesity continuously.

The present study indicated that the ratio of overweight and obese Chinese-Korean children and adolescents increased to a higher level， although the rate of malnutrition of Chinese-Korean children and adolescents （mainly stunting） had decreased in the past 15 years. Children and adolescents of the Chinese-Korean ethnicity and Han ethnicity had the same tendency［42，57］. Since the Reform and Opening-Up Policy （1978）， China has made great progress in economic development and improvement of the standard of living. Moreover，the government initiated a scheme to reduce malnutrition in children and adolescents， such as nutritious breakfast and lunch［58-59］. Therefore， the high prevalence of malnutrition in Chinese children and adolescents gradually decreased in recent decades［60-61］. However， the ratio of children and adolescent obesity had increased dramatically in urban areas during the last 2 decades［62］. Many studies have reported that risk factors of obesity in children and adolescents included high socio-economic status， parents with poor health knowledge， high-calorie food intake， and poor physical activity in China［63-64］. The local government should focus on preventing childhood obesity by shaping policies and practices that influence the environments wherein children live， play， and learn and thereby improve their health. Over the pastdecade， a 43% reduction in the obesity rate was noted among children aged 2-5 years in the United States in 2014［65］， owing to a combination of the state， local， and federal policies aimed at reducing obesity. In China， despite decades of efforts to alleviate the problem of childhood obesity， there has been very little improvement.

The study demonstrated that during the survey period， irrespective of the setting （urban or rural），the minus 2Z of BMI-for-age of Chinese-Korean children and adolescents gradually approached the WHO wasting reference value （Minus 2Z-Score）. The averages and 1Z-Scores of the BMI-for-age of Chinese-Korean children and adolescents were higher than those of the WHO references. These values， as previously mentioned， increased concurrently with the gradual improvement of family income and education level in Yanbian， which led to a decrease in the ratio of wasting of Chinese-Korean children and adolescents aged 7-18 years and the value approached the WHO reference value［66-67］. There were 2 criteria to evaluate the nutritional state of children and adolescents in China， which can be listed as following： 1） The boundary range formulated by the Working Group of Obesity，China［68］in 2004 to use BMI-for-age of school children and adolescents in order to screen for overweight and obesity， and 2） the boundary range set by Ji Cheng-Ye et al.［69］in 2014 to use age-related screening for malnutrition of the school children and adolescents. The universal criterion worldwide is the WHO Child Growth Standard［23］（2007 version）， which also was adopted in this study. Our results show that it was reasonable to evaluate the malnutrition status （stunting and wasting） of Chinese-Korean children and adolescents using this criterion， but there might be some deficiencies in evaluating overweight and obesity. Therefore， further studies are needed to establish a better evaluation criterion that can be used to determine the state of nutrition in Chinese-Korean children and adolescents.

CONCLUSION

From the point of historical development， we used cross-sectional data from the national physical constitution surveys of 1995， 2000， 2005， and 2010，and analyzed the gradual change in nutrition in Chinese-Korean children and adolescents aged 7-18 in Yanbian， China. From our results， we conclude the following：

1） The height and weight of Chinese-Korean children and adolescents have gradually increased in the past 15 years， and the physical differences between children in the urban and the rural areas of Yanbian have waned. Irrespective of rural or urban areas， the rate of malnutrition of Chinese-Korean children and adolescents （mainly stunting） has decreased， with a reduction in the difference in malnutrition status between the urban and rural populations.

2） Regardless of urban or rural areas， the rate of overweight and obesity among Chinese-Korean children and adolescents has increased to a higher level.

ACKNOWLEDGEMENTS

We would like to make a grateful acknowledgement to all persons who have helped us with the CNSSCH. Our deepest gratitude also goes to Professor CHEN Chun Ming for his constructive suggestions，insightful comments and selfless assistance. We also greatly appreciate the assistance from Lu Jinkui and Deng Yuqiang in the College of Physical Education & Health， East China Normal University.

Accepted： December 10， 2015

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Biomed Environ Sci， 2016； 29（1）： 24-40 10.3967/bes2016.003 ISSN： 0895-3988

August 5， 2015；

*This study was supported by Philosophy and Social Sciences Planning of Shanghai， China （2010BTY003）.

#Correspondence should be addressed to YIN Xiao Jian， Tel/Fax： 86-21-54345481， E-mail： xjyin1965@163.com

Biographical note of the first author： YIN Xiao Jian， male， born in 1965， PhD， professor of child and adolescent health.

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Biomedical and Environmental Sciences

2016年1期