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Updated: Jun 15, 2026
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Applying Advanced In Vitro Culturing Technology to Study the Human Gut Microbiota
Published on: February 15, 2019
Acquisition, evolution and maintenance of the normal gut microbiota
G T Macfarlane1, L E Macfarlane
1University of Dundee, Microbiology and Gut Biology Group, Ninewells Hospital Medical School, Dundee, UK. g.t.macfarlane@dundee.ac.uk
Digestive Diseases (Basel, Switzerland)
|March 6, 2010
Summary
The human gut microbiota develops after birth, with bacterial numbers increasing along the digestive tract, especially in the colon. Aging and external factors like antibiotics alter this complex gut ecosystem, particularly in older adults.
Area of Science:
- Microbiology
- Gastroenterology
- Human Physiology
Background:
- The gut microbiota is established post-birth from maternal sources and evolves over time.
- Bacterial colonization varies along the digestive tract, with low numbers in the stomach and higher counts in the distal ileum and colon.
- The colonic microbiota is a complex ecosystem influenced by numerous host and environmental factors.
Purpose of the Study:
- To describe the development and composition of the human gut microbiota.
- To identify factors influencing microbial community structure and function.
- To characterize age-related changes in the gut microbiota.
Main Methods:
- Review of existing literature on gut microbiota development and composition.
- Analysis of factors affecting microbial growth and metabolism in the digestive tract.
- Comparison of gut microbiota profiles in different age groups and under various conditions.
Main Results:
- Bacterial populations increase distally through the gastrointestinal tract, with the colon hosting the most complex communities.
- Diet, host physiology, genetics, and external factors like drugs and hospitalization significantly impact microbiota composition.
- Older adults exhibit altered microbiota profiles, with reduced bifidobacteria and increased enterobacteria and clostridia compared to younger adults.
Conclusions:
- The gut microbiota is dynamic and influenced by a multitude of factors throughout life.
- Aging leads to significant shifts in gut microbial composition, with potential implications for host health.
- Environmental exposures, such as antibiotic use and hospitalization, can disrupt the colonic microbiota, though the metabolic consequences require further investigation.
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