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Updated: Mar 30, 2026

Oral Biofilm Sampling for Microbiome Analysis in Healthy Children
Published on: December 31, 2017
Correlation between body mass index and faecal microbiota from children
A Ignacio1, M R Fernandes1, V A A Rodrigues1
1Anaerobe Laboratory, Department of Microbiology, Institute of Biomedical Science, University of Sao Paulo, Sao Paulo, SP, Brazil.
Childhood obesity is linked to specific gut bacteria. Obese children have higher levels of Bacteroides fragilis group and Lactobacillus spp., while lean children have more Bifidobacterium spp.
Area of Science:
- Microbiology
- Pediatric Health
- Nutritional Science
Background:
- Childhood obesity is a growing global health concern, increasing the risk of adult obesity and related diseases.
- The gut microbiome plays a crucial role in host metabolism and health.
- Understanding the gut microbial ecosystem in obese children is vital for developing targeted interventions.
Purpose of the Study:
- To investigate the differences in gut microbiota composition between obese, overweight, and lean children.
- To determine the correlation between specific bacterial groups and Body Mass Index (BMI) in children.
Main Methods:
- Faecal samples from 84 children (30 obese, 24 overweight, 30 lean) were analyzed.
- Bacterial populations including Bacteroides fragilis group, Clostridium spp., Bifidobacterium spp., Escherichia coli, Lactobacillus spp., and Methanobrevibacter smithii were quantified using culture techniques and quantitative PCR.
- Statistical analysis was performed to correlate bacterial concentrations with BMI.
Main Results:
- The Bacteroides fragilis group and Lactobacillus spp. were found in significantly higher concentrations in obese and overweight children compared to lean children.
- Faecal concentrations of the B. fragilis group and Lactobacillus spp. showed a positive correlation with BMI.
- Bifidobacterium spp. were more abundant in lean children and exhibited a negative correlation with BMI.
Conclusions:
- Significant differences exist in the gut microbial ecosystem of obese children compared to lean children.
- The abundance of Lactobacillus spp. and the B. fragilis group is significantly associated with higher BMI in children.
- Gut microbiota composition may serve as a potential biomarker or therapeutic target for childhood obesity.
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