Study on Dietary Nutrition Intervention Techniques for Children Obesity
Study on Dietary Nutrition Intervention Techniques for Children Obesity
With the rapid development of society and economy, children's simple obesity is the rising in
 the world and has become a chronic disease which is one of the biggest public health
 challenges in the world. It is a serious threat to the health of children and their
 adulthood. The overweight and obesity is induced by the genetic and environmental factors.
 The environmental factors are very important, while the dietary factors are the driving
 factors of many chronic diseases including obesity. This study focus on the dietary
 intervention of childhood obesity to build healthy intestinal flora. The interventing food
 was based on a natural health food - fruit and vegetable fermentation liquid, and combined
 with other probiotic dietary factors, dietary fiber and oligosaccharides. The implementation
 of the study will help to reveal the fuction mechanism of intestinal bacteria in the obese
 children and normal children, and to construct healthy micro environment of intestinal flor.
 According to the positive effect factors, the study will propose a healthy diet and nutrition
 intervention model for obese children, which is significant to social health especially to
 children's health.

 To investigate the accuracy of MRI in quantifying liver fat with magnetic resonance
 spectroscopy (MRS) as a reference. A secondary goal was to assess the prevalence of
 nonalcoholic fatty liver disease in overweight and obese Chinese children and adolescents.
Before academic examination, letter to parents, informed consent and volunteer questionnaire
 are released to school children and their guardians. We tell the volunteers and their
 guardians what about this study and invite them to participate this study. Only the
 volunteers and guardians signature on the letter to parents and informed consent are able to
 the research objects.

 Experimental procedures:

 Two times of medical exams, blood and stool sample collection is required for the whole
 experiment research. The first time exams and sample collection is carried on during academic
 examination; the second time is carried on after the intervention.

 Recruit of research objects:

 According to academic examination and volunteer questionnaires, about 300 healthy children
 without in taking antibiotics before 3 months are recruited and their BMI should be in the
 obese range. Then their waist circumference and the ratio of body fat are measured. If the
 ratio of waist size to weight of them is >0.46 and they have higher percentage of body fat
 (>20% for boys and under 12 years old girls, >25% for 12 years old girls), the data are
 collected and input to the database. About 40 healthy children between 15-18 years old are
 recruited to participate the next intervention research.

 General body examination:

 In academic examination, the student's basic medical data including height and weight are
 recorded, and then their BMI are calculated. If his/her BMI are in the obese range, his/her
 body composition are measured and recorded.

 MRI and MRS test:

 All patients underwent MRI scanning performed by an experienced technologist using a 3 Tesla
 MR unit (MAGNETOM Skyra, Siemens Healthcare, Erlangen, Germany). MRI and MRS were performed
 with multi-echo Dixon and HISTO sequences, respectively, to calculate hepatic proton density
 fat fraction (PDFF).

 Blood collection, preservation and test:

 Blood collection and preservation are proceed in standard of medical examination. When
 collecting the data of obesity, the tests of blood count, blood glucose, serum lipid and
 liver function should be processed for obese children. When intervening, more tests including
 blood count, blood glucose, blood lipids, liver function, hemoglobin, cytokines, insulin,
 high sensitivity C-reactive protein, leptin and somatomedin C should be processed.

 Stool collection, preservation and detection:

 50 ml centrifuge tubes are used to collect stool samples. Each tube is marked a unique
 encoding corresponds to a volunteer. When volunteers collecting stool samples, they transfer
 the stool samples into sterile centrifuge tube using sterile swabs or toothpicks as soon as
 possible. The collecting samples should be more than 10g. The centrifuge tubes should be put
 in low-temperature place , then transfer to refrigerator and stored at -80 ℃ until to DNA
 extraction and other testing. The tests including short chain fatty acids content (SCFA), pH,
 water content, immune factors sIgA and Calprotectin are processed.

 16S rRNA gene sequencing of bacteria in stools:

 DNA extraction:

 For each sample, about 0.2g stool is weighted and the total DNA is extracted using fecal
 genomic DNA extraction Kit (Qiagen, model DP328). And then the concentration and purity of
 extracted DNA were measured using NanoDrop (Thermo, 2000C) to guarantee each sample meets the
 sequencing requirement.

 Sample sequencing:

 PCR amplification of 16S rRNA gene (V3-V4) are performed with universal forward primers
 5'-ACTCCTACGGGAGGCAGCAG-3' and reverse primer 5'-GGACTACVSGGGTATCTAAT-3'. The amplification
 system include sterile water 19.375 ul, buffer 2.5ul, template 1ul, primers 1ul, Pyrobest DNA
 polymerase 0.125ul. PCR cycling conditions were as follows: 94 ℃ 5min, followed by some
 cycles including 94℃ denaturing for 30s, 50℃ renaturing for 30s,72℃ extending for 30s, then
 72℃ extending for 5min. PCR product electrophoresis are performed to determine the
 appropriate PCR product with different application cycles. After connecting amplified
 products to tagged primers and labels, paired-end sequencing are performed with the
 sequencing platform of Illumina MiSeq, and the read length is about 250bp.

 Intervention treatment on childhood obesity with PFE:

 After 16S rRNA gene sequencing, about 40 obese volunteers in high school and with similar
 intestinal flora profiles are selected to participate the intervention treatment research.
 The intervening food is "Dr. Ephraim" plant fermentation extract (PFE). Without changing the
 previous diets of research objects, each research object drinks drinking 30mL PFE at morning
 and evening enzymes respectively, and the intervention last for 8 weeks. Before and after
 8-week intervention, stool and blood samples of research objects are collected and analyzed
 to obtain their physiological and biochemical indexes. The all 16S rRNA gene of fecal samples
 in each stage are sequenced.
Inclusion Criteria:

 -  People whose BMI>27 and Age between 15-18;the value of waistline/weight >0.46; the
 value of body composition >20%.

 Exclusion Criteria:

 -  People treated by antibiotic drugs in 3 months;People with gastrointestinal
 diseases;People with Type I diabetes, any eating disorders such as bulimia or anorexia
 nervosa; Prader-Willi patients and obesity is part of clinical syndrome with other
 disorders.