A good gut feeling
Diversity of ’good’ bacteria in our gut is essential in maintaining good health, writes MICHELLE McDONAGH
ADVANCES IN molecular technologies have seen the humble gut microbiota become a crucial target for improving human health and reducing disease risk over the past decade. It is now accepted that the human intestinal microbiota plays an important and complex role in the maintenance of our health – this knowledge has the potential to offer targeted dietary intervention to promote and maintain health in vulnerable populations throughout life, particularly during periods such as infancy and old age.
“The human intestine is full of bacteria which is why we are always urged to wash our hands after going to the toilet. We think it’s all bad, but it turns out there is a community of organisms down there that is essential for normal health,” explains Dr Paul O’Toole of the department of microbiology and alimentary pharmabiotic centre in University College Cork.
The human body relies on vast numbers of microbes to function efficiently and healthily. (Microbiota refer to the complete set of micro-organisms present in an environment including viruses, bacteria, protozoa, fungi and yeast.) There are up to 100 trillion microbes in the human gastrointestinal tract alone. There are in fact, 10 times more bacterial cells in the GI tract than human cells in the body and 100 times more bacterial genes than human genes inside the human body.
“If Martians came to earth and looked at the human body, they would say ‘Wow, isn’t that a clever thing the microbiota have developed to carry themselves around in’,” Dr O’Toole quips.
The landmark Eldermet project at UCC ( eldermet.ucc.ie) is one of several worldwide projects that is working to catalogue the microbiota of the human gut. Researchers on the project are exploring interactions between the microbiota, diet, health and lifestyle in older Irish adults.
Eldermet, which is co-funded by the Department of Agriculture, Food and Marine, and the Health Research Board’s food for health research initiative, will provide fundamental evidence upon which future functional health foods, specific to older populations, will be based. The project is a collaborative effort between scientists and clinicians at UCC, Teagasc Moorepark’s Food Research Centre and the HSE hospitals in the Cork area.
Dr O’Toole, who is the project co-ordinator of Eldermet explains: “It’s only since we have had the ability to examine the composition of the microbiota of the gut relatively recently with cutting-edge, culture-independent techniques that we have begun to realise how much more important it is than was previously thought. Alterations in the gut bacteria have been increasingly linked to variations in health, including obesity, heart disease and inflammatory conditions and there is emerging evidence that gut microbiota can even affect how the brain works and could be related to the rate of loss of mental function. It’s still not clear which body defence functions and mechanisms are most dependent on gut bacteria and this is what we aim to find out.”