Objective:To investigate the status of blood mineral content of children aged 3 to 12 years in Chinese cities and countryside and explore the possible related influencing factors .Methods: The multistage stratified cluster random sampling was used to select one kindergarten and one primary school in seven cities ( Beijing and Guangzhou and so on ) and two towns randomly .Firstly, we selected one bottom class , middle class , top class in one kindergarten and one second grade and fifth grade in one pri-mary school randomly .Then all of the healthful students of these classes were investigated and the blood mineral content of calcium , magnesium, lead, iron, copper, and zinc were detected.Results:In the re-search, 1 842 students were investigated .The means of calcium, magnesium, lead, iron, copper, and zinc were in the standard range .The blood lead content of the boys was higher than that of the girls .The blood mineral content of different ages had statistical significance .The blood calcium and blood copper contents of the preschool children were higher than those of the school children .However , the school children had significantly higher blood lead , iron, and zinc contents in comparison with those of the pre-school children .The incidences of iron deficiency and zinc deficiency were 35.5%and 39.6%, respec-tively .The incidence of iron deficiency and zinc deficiency of different ages had statistical significance , and with the age increasing , the incidence showed a decreasing trend .The incidences of iron deficiency and zinc deficiency of children whose age was more than or equal to 3 years and less than 4 years were up to 47.1%and 64.6%, respectively.The incidence of iron deficiency of the children in the countryside area was significantly higher than those in the first-tier cities.However, the incidence of zinc deficiency of the children in the countryside area was significantly lower than those in the first-tier cities and second-tier cities.Conclusion:The status of iron deficiency and zinc deficiency of children aged 3 to 12 years in Chinese cities and countryside were still serious .We should pay more attention to the nutrition interven-tional research on iron and zinc .

Objective: To investigate breakfast status and influencing factors among children aged 6-17 in China in 2010-2012. Methods: Data were collected from China National Nutrition and Health Surveillance in 2010-2012. By using multi-stage stratified sampling and population proportional stratified random sampling method, the research objects were 29 393 children, who aged 6 to 17 y from 150 sites in 31 provinces in mainland China. The information of breakfast frequency and the numbers of breakfast dinning out (in restaurant and at schools) in the past week with seven days were collected by questionnaire; and compared by different ages, genders and areas. Results: During the past week, 91.1% (26 776/29 393) of the children aged 6 to 17 y had their breakfast daily, and 94.6% (13 457/14 221) of children aged 6 to 11 y was higher than 87.8% (13 319/15 172) of children aged 12 to 17 y, the highest proportion of the children never eat breakfast (0 time in the past week) found in poor rural areas was 3.6% (189/5 261), the ratio of big cities, small-medium cities and normal rural areas was 1.1% (77/7 104), 0.6% (51/8 361), and 0.6% (54/8 667), respectively (P<0.001). The rate of boys and girls ate their breakfast daily in the past week were 91.3% (13 481/14 761), and 90.9% (13 295/14 632), respectively (P>0.05). Totally 42.2% (12 398/29 393) of children ate breakfast outside-home (the restaurant and the school) in the past week, the percentage of children aged 12 to 17 y and poor rural areas was higher, 50.9% (7 722/15 172), and 52.4% (2 756/5 261), respectively (P<0.001). 42.1% (6 208/14 761) boys and 42.3% (6 190/14 632) girls ate their breakfast outside-home (P>0.05). The place of most school-age children eat outside-home was school, the ratio was 32.2% (9 477/29 393). Conclusion It was common for school-aged children in China to skip breakfast during their daily lives, especially in poor rural areas and older children, lots of school-aged children ate breakfast outside-home, and most of them ate breakfast in school.

Abstract The prevalence of overweight and obesity among children and adolescents in China is increasing during recent years, which could be influenced by multiple factors such as genetics, diet and lifestyle. To understand the relationship between meal timing, frequency with childhood overweight and obesity, the paper reviews recent studies on the relationship between meal or snack timing, frequency with overweight and obesity among children and adolescents, so as to provide scientific evidence for obesity prevention and control.

Abstract The rate of overweight and obesity in Chinese children and adolescents is gradually increasing, and it has multiple hazards for their health. Overweight and obesity are affected by many factors such as genetics and environment. The home food environment is very important among the many factors affecting children s overweight and obesity. This paper analyzes the relationship between parents feeding behaviors, including pressure eating, restricted eating and food as reward, accessibility and usability of family food, with overweight and obesity of children and adolescents, aiming to provide a scientific reference for controlling children overweight and obesity by focusing on home food environment.

Objective: To analyze the height changes among children who had received subsidies of the National Nutrition Improvement Program for Rural Compulsory Education Students (NNIPRCES) by comparing data from the year of 2012 and 2017. Methods: Among 699 counties where NNIPRCES was implemented, at least 10% of elementary schools and primary middle schools with different food supply modes (school canteen meals, company meals, and mix meals) in the county were selected randomly. Forty students from one or two classes from each grade (grade 1 to grade 9) were randomly selected, to ensure equal proportion of boys and girls in each grade were surveyed, data on height from 1 655 793 students measured in 2012 were compared with 1 419 281 students measured in 2017. Height was measured by metal height pole within 0.1 cm accuracy. Results: From 2012 to 2017, the average increase of height in boys and girls aged 6-15 years was 1.9 and 2.0 cm, respectively. Among them, maximum increment was found in boys at the age of 13 years and in girls at the age of 12 years, respectively, which was 3.0 and 2.8 cm. The average increase in boys from the central and western region was 2.1 and 2.2 cm, respectively, while increase in girls from the central and western region was both 2.2 cm. Compared with the results from 2012, height of boys with the 5th, 50th and 95th height percentiles in 2012 increased by 1.7, 2.0 and 2.1 cm, respectively in 2017, while the increase in girls was 2.1, 2.0 and 2.2 cm, respectively. The average increment of western students with the 5th and 95th height percentiles was higher than those of students from the central region. Conclusion The average height of students has increased after the implementation of NNIPRCES. However, the development was unbalanced between the central and western region, which requires more targeted intervening strategies to improve the nutritional status of students.

Objective: To explore the prevalence of anemia and related factors among left-behind children in poverty-stricken rural areas in China, to provide basic information for anemia prevention and treatment for children. Methods: Data from the National Nutrition Improvement Program for Rural Compulsory Education Students in 2016 were used to express the prevalence of anemia among left-behind children. By using the multistage stratified random cluster sampling method, left-behind children of the 6-17-years-old in poverty-stricken rural areas were recruited in this study. Blood hemoglobin concentration of these students was determined by cyanmethemoglobin method. Anemia was judged by the WHO recommended standard and combined with the sea level elevation correction standard. Frequencies of food intake were collected through questionnaires. Data was then available for analysis including the level of hemoglobin and anemia rates. Relationship between anemia and food intakes as well as other influential factors was also analyzed. Results: The overall anemia prevalence (AP) was 11.6% among the participants. Rates of AP among the 6-, 7-, 15- and 16-17-years-old were 21.1%, 18.0%, 20.6% and 17.3%, respectively. Rates of AP among left-behind girls of 10-11-years-old and the 13-15-years-old were significantly higher than those in boys at the same age (P<0.01) group. Factors including: being girls (OR=1.34, 95%CI: 1.23-1.45), at grade 7 to 9 (OR=1.47, 95%CI:1.30-1.67) and mother being migrant worker (OR=1.32, 95%CI:1.16- 1.50) had higher proportions of getting anemia. Factors as living in the western area (OR=0.85, 95%CI: 0.78-0.93), taking breakfast every day (OR=0.70, 95%CI: 0.64-0.76), having meat more than twice per week (OR=0.84, 95%CI: 0.75-0.93) and having two kinds of vegetables per day (OR=0.85, 95%CI: 0.75-0.96) appeared protective. Conclusions Prevalence of anemia in left-behind children from the poverty-stricken rural areas was high, including junior middle school students from grade 7 to 9 at the early stage of youth development, girls and children with mothers as migrant workers. Anemia should be reduced by promoting the protective factors as having breakfast, increasing intakes of meat and fresh vegetables.

Objective: To analyze changes of school canteen construction and canteen meal provision in surveilled schools after the initiation of the National Nutrition Improvement Program for Rural Compulsory Education Student (NNIPRCES), therefore to provide data basis for improving efficacy of school canteen meals. Methods: From 2012 to 2017, among the 699 trial counties in 22 provinces under NNIPRCES, at least 10% of elementary schools and middle schools with each food supply model (canteen meals, enterprise meals, and family meals) were randomly selected in each county in each year. Questionnaire survey was conducted to collect school canteen construction and meal provision information. The sample size were around 8 000 to 11 000 schools every year. Results: From 2012 to 2017, the proportion of schools that have canteens only, have both canteen and dining room, as well as those have canteen and dining room with tables and chairs significantly increased with years(χ 2=3 043.95, 6 383.85, 6 731.17, P<0.01). The proportion of schools having canteen increased from 59.5% in 2012 to 87.0% in 2017. The proportion of schools with canteen providing breakfast, lunch or dinner varied across years(χ 2=51.85, 144.96, 189.19, P<0.01). The varieties of food groups of three meals all significantly increased during 2012, 2014 and 2017(χ 2=702.30, 892.38, 550.55, P<0.01). The canteen construction indicators, proportion of canteens providing three meals, and food groups included in three meals all significantly differed between elementary schools and middle schools, also between schools of central area and western area(P<0.05). The changing patterns with year were significantly different in elementary schools and middle schools, and in schools of central area and western area(P<0.05). Conclusion After the implementation of NNIPRCES, canteen construction and food variety in canteen meals significantly improved during 2012 to 2017. However, there are still gaps between changes of canteen construction and canteen meal provision. It is necessary to overcome obstacles to further increase the proportion of schools with canteen offering meals and the variety of food of meals.

Objective: To analyze the usage of catering software and the creation of recipes by schools, as part of the Nutrition Improvement Program for Rural Compulsory Education Students (NIPRCES) 2013-2017. Methods: In each county of the 699 trial counties across 22 provinces in central and western area of China under the NNIPRCES, no less than 10% of primary and junior middle schools were randomly selected according to their catering mode (i.e., school feeding, food packages, and family feeding). School questionnaires were used to collect information concerning the schools and the creation of recipes. Results: From 2013 to 2017, the utilization rate of catering software was 11.7%, 8.0%, 17.8%, 16.9%, and 14.0%, respectively with significant differences(χ 2=345.09，P<0.01). The creators of school-meal recipes included schools, the Education Bureau, hospitals and colleges, the centers of disease prevention and control. Differences were observed in the proportion of recipe creators across school type, area, and catering mode, while annual trends also varied (P<0.01), as indicated by the following proportions: 74.9%, 20.0%, 3.7%, 1.3%, respectively. Food safety was identified as the main factor that needs to be considered when creating school recipes, the proportions of which were 58.0%, 78.4%, 70.6%, and 87.4% from 2014 to 2017. Conclusion From 2013 to 2017, the utilization rate and the frequency of catering software were both relatively low, and recipe creation was in need of professional guidance. It is necessary to strengthen the popularization of catering software and improve the nutritional knowledge and skills of canteen workers to ensure the quality of school meals.

Objective: To analyze the status of parents sharing meal expenses in the national pilot areas of the Nutrition Improvement Program for Rural Compulsory Education Students (NIPRCES) and its influencing factors, so as to provide scientific data for promoting the proper implementation of the NIPRCES and the healthy development of students. Methods: In the 726 national pilot counties in 22 provinces where the NIPRCES was implemented, 8 109 primary and junior high schools were selected as the survey objects and included in the analysis according to the three feeding methods of canteen feeding, enterprise feeding and mixed feeding. Data such as the basic information of the schools and counties, and the status of parents sharing meal expenses were collected through questionnaires. Multivariate Logistic regression analysis was used to analyze the influencing factors of parents sharing meal expenses. Results: In the national pilot areas of the NIPRCES, schools where parents shared meal costs accounted for 30.2% of all monitored schools in 2019. In central and western areas, the proportion of schools where parents shared meal costs were 51.5% and 20.3%, respectively. In schools where parents shared meal costs, no matter in primary school or junior high school, the difference in the amount of meal expenses shared by parents of students in middle and western schools was statistically significant ( χ 2= 181.78 , 89.54, P <0.01). Among 38.7% of the parents of primary school students in the central region shared meal expenses of ≥2 yuan, and 47.5% of the parents of primary school students in the western region. Multivariate Logistic regression analysis showed that the parents of schools in the central region, junior high schools or nine year system schools, canteen feeding or other feeding, large school size, the nutritious meal subsidy used for lunch, middle and high family income level, medium and low input level of the monitoring counties, monitoring counties with other nutrition public welfare projects and insufficient working funds share a higher proportion of meal expenses ( OR=3.22, 1.51, 1.36, 1.74, 3.74, 1.38, 11.58, 2.40, 3.15, 1.50, 2.12, 3.36, 1.34, P < 0.05). Conclusion The proportion of meals shared by parents of school students in the NIPRCES implementation area was relatively low, which may be affected by factors such as economic level, feeding mode, school scale, etc.

Objective: To analyze the usage and influencing factors of quantified recipes in schools in the pilot areas of the Nutrition Improvement Program for Rural Compulsory Education Students (NIPRCES), and to provide references for student meal quality improvement. Methods: In 726 national pilot counties in 22 provinces where the NIPRCES was implemented, a total of 7 808 schools were included in the analysis as the survey objects in 2019. Data, including the usage of quantified recipes in schools and related factors, were collected through questionnaires. Multivariate Logistic regression was used to analyze the influencing factors of the schools use of quantified recipes. Results: Among the national pilot counties where the NIPRCES was implemented, 66.6 % of the monitored schools used quantified recipes, of which 69.7% of schools in the central region used quantified recipes, it was higher than that in the west region(65.2%) ( χ 2=15.13, P <0.01). Multivariate Logistic regression analysis showed that factors such as the schools in the central region, county based schools, the training frequency of canteen with 1-2 times per semester or once or more per month, regular training of nutrition knowledge, recipes provided by other departments, consideration of nutrition matching when formulating recipes, using catering software, providing local dietary allowances were positively correlated with the use of quantified recipes in schools( OR=1.31,0.72,1.44,1.73,1.75,3.20,2.15,2.72,1.17,P <0.05). Conclusion The proportion of using quantified recipes of schools in the NIPRCES area was relatively low, which might be affected by factors including the regional economic level, canteen training, and recipes sources. It is recommended to strengthen the construction of professional teams and canteen training. Schools need to be encouraged to use quantified recipes and promote school catering scientifically to improve healthy growth of students.