Investigation Of Dietary Nutrition Status And Analysis Of Intestinal Microbial Characteristics Of Children Aged 8～12 Years In A School In Maqu County,Gannan Prefecture

Objective:To investigate the physical development and dietary nutrition status of children aged 8～12 years in Chengguan nine-year school in Maqu County,Gannan Tibetan Autonomous Prefecture,and the intestinal microbiological characteristics of children of different ethnic groups（Han and Tibetan）in the school,and to conduct correlation analysis to clarify the current status of children’s physical development and its influencing factors,so as to provide a basis for further suggestions of targeted interventions.Methods:Children aged 8～12 years in Chengguan nine-year school in Maqu County,Gannan Prefecture,were used as the study subjects.（1）Basic information and dietary information of the study subjects were collected through questionnaires,and physical measurements were taken.Children were divided into three groups:lean,normal and overweight/obesity according to body mass index（BMI）by age,and the dietary and nutrient intake of each group was evaluated and compared among the three groups;（2）Stool samples were collected for 16S r DNA sequencing,and the differences in gut microbial composition and diversity between Han and Tibetan children with different body sizes from 8～12 were analyzed using R language and SPSS,and the correlation between dietary and nutrient intake and gut microbial abundance was explored by Spearman’s rank correlation analysis.Results:（1）A total of 155 children were investigated,including 70 boys and 85girls.Approximately 63.9%（99/155 cases）of the children had normal physical development,and the detection rates of lean and overweight/obesity were 21.3%（33/155 cases）and 14.8%（23/155 cases）,respectively.There were no statistical differences in gender,ethnicity,parental education,occupation and monthly family income between the lean,normal and overweight/obesity groups（P>0.05）.（2）The surveyed children had the highest intake of cereals and potatoes（76.8%）,followed by soybeans and nuts,fruits,livestock and meat,and eggs（34.8%,29.7%,29.7%,and 25.8%）,and the intake of vegetables,aquatic products,and milk and milk products did not meet the standard.There was a statistical difference（P<0.05）in the intake of fruits and livestock and poultry meat among the three groups of children in the lean,normal and overweight/obesity groups,with the lean group having the highest intake of fruits and the normal group having the highest intake of livestock and poultry meat.There was no statistical difference between the three groups in the intake of other food groups（P>0.05）.（3）The surveyed children had the highest rate of attainment of protein intake（65.8%）,followed by vitamin B₁,carbohydrate,vitamin E,and vitamin C（61.9%,46.5%,40.6%,and 36.8%）,and the lowest rate of attainment of fat,vitamin B₂,and zinc.The daily intakes of energy,protein,fat,carbohydrate,dietary fiber,vitamin E,vitamin B₁,and zinc were statistically different among children in the lean,normal,and overweight/obesity groups（P<0.05）,and the overweight/obesity group had the highest intakes of all of these nutrients.While the intakes of other nutrients were not statistically different between the three groups（P>0.05）.（4）The dominant organisms at the phylum level in both Han and Tibetan children were Firmicutes,Bacteroidetes,Actinomyces and Proteobacteria.In Han Chinese children,the relative abundance of the four dominant phyla was statistically different among the Han lean group,the Han normal group and the Han overweight/obesity group（P<0.05）.Among Tibetan children,only the relative abundance of Proteobacteria was statistically different between the Tibetan lean group,Tibetan normal group and Tibetan overweight/obesity group（P<0.05）.（5）At the genus level,the relatively abundant microorganisms were from the genera Faecalibacterium,Bacteroides,Prevotella＿9,Megamonas,Agathobacter,Subdoligranulum,Dialister,unclassified＿Lachnospiraceae,Roseburia,and unclassified＿[Eubacterium]＿coprostanoligenes＿group.Among them,the relative abundances of Faecalibacterium and Bacteroides were statistically different between HL,HN,and HO groups（P<0.05）,while the relative abundances of Megamonas were statistically different between TL,TN,and TO groups（P<0.05）.（6）There were statistical differences among Han children with different body types in the composition,diversity and community structure of intestinal microorganisms（P<0.05）,while no statistical differences among Tibetan children with different body types in the above indicators（P>0.05）.Han Chinese children had a higher proportion of intestinal microorganism intestinal type 2（representative bacteria Bacteroides）,and Tibetan children had a higher proportion of intestinal microorganism intestinal type 1（representative bacteria Dialister）and intestinal type3（representative bacteria Prevotella＿9）,and the difference in intestinal type composition between the two ethnic groups was statistically significant（P<0.05）.（7）Correlation analysis showed that dietary and nutrient intakes were correlated with the relative abundance of microorganisms such as Desulfovibrio and Bifidobacterium at the phylum and genus levels（P<0.05）.Conclusions:（1）The detection rates of lean and overweight/obesity were high in children aged 8～12 years in Chengguan Nine-Year School of Maqu County,Gannan Prefecture,and there was an unreasonable dietary structure,mainly in the form of low intake of vegetables,aquatic products,milk and dairy products,and significantly insufficient intake of some dietary nutrients such as energy,vitamin A,vitamin C and vitamin B₂.（2）Compared with Tibetan children,there were statistical differences in the abundance,diversity and community structure of intestinal microflora among Han children with different body sizes,suggesting that ethnic factors may have a greater influence on the composition of intestinal microflora.