Microbiologists believe that the human gut contains approximately three trillion bacteria that aid digestion and provide protection against infections. The human gut refers to the gastrointestinal tract, which begins at the end of the mouth and ends at the rectum.
From the treatment of cancer to the management of chronic diseases, scientists are increasingly finding a link back to the good bacteria that live in our stomachs and intestines.
Now, research by a UK doctor argues that the presence of a certain type of bacteria in the gut might be linked with colorectal cancer. To be sure, the researchers said they need to study the matter in more detail before they can say whether the bacteria increases one’s chances of getting the disease or if the bacteria are merely present in larger numbers in people who already have colon cancer.
How do gut microbes help us?
Research shows that the good bacteria in our tummies and intestines may have more far-reaching consequences than we realised earlier (researchers have found that some of these good bacteria might live in the appendix – so it’s probably not as useless as we thought). Broadly, these bacteria help in:
Digestion: Gut microbes help in the digestion of foods like plant polysaccharides (a type of carbohydrate) that are rich in xylan, pectin and arabinose compounds.
Staying healthy: Along with ensuring maximum absorption and a good bowel movement, gut microbes also synthesize some essential micronutrients such as vitamin B and K.
Fighting infection: They interact with the immune cells to prevent the growth of pathogens (microorganisms that cause infection) in the gut.
Some species of bacteria in the gut may be linked to colorectal cancer, according to research by Dr Kaitlin Wade, PhD, Bristol Medical School, UK. Dr Wade shared her findings during the 2019 National Cancer Research Institute (NCRI) Cancer Conference in Glasgow, UK, on 4 November.
Dr Wade and her research team conducted a genome-wide association study (GWAS) with 3,890 people who had participated in any of three genome-wide association studies: the Flemish Gut Flora Project, the German Food Chain Plus study, and the PopGen study. Additionally, the team analyzed data from 120,328 people in the international Genetics and Epidemiology of Colorectal Cancer Consortium. Genome-wide association studies compare genes of two different people with a similar health condition. All to find out if any variation in the human gut microbiome, like the number of bacteria or the numbers of different types of bacteria, could have an impact on colorectal cancer.
The research showed that an unclassified type of bacteria from a bacterial group called “Bacteroidales” increases the risk of colorectal cancer by 2-15%.
Dr Wade further added that the research supports some previous studies which have shown the presence of Bacteriodales in larger numbers in people with colorectal cancer than those without the disease.
Need for more research
Although the research showed the involvement of gut bacteria in colon cancer, Dr Wade said it’s really difficult to conclude whether components of the gut microbiome are causing bowel cancer or the disease itself leads to variation in the gut microbiome.
The scientist further added that there is a need for extended research to classify the exact species or strain of bacteria in the Bacteroidales group that might be causing cancer.
This article was written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health. For more information, please read Colorectal Cancer: Symptoms, Diagnosis, Treatment.