Gut bacteria can manufacture defences against cancer and inflammatory bowel disease

Feb 06, 2009

(PhysOrg.com) -- Bacteria naturally present in the human gut could produce substances that help to protect against colon cancer and provide therapy for inflammatory bowel disease.

In a paper published in the journal Microbiology, researchers from the University of Aberdeen Rowett Institute of Nutrition and Health and from the MTT Agrifood Research Institute in Finland report initial studies showing that bacteria in the human gut convert linoleic acid, a naturally-occurring fat in the diet, into a form called conjugated linoleic acid (CLA) which is absorbed by the gut wall.

There are different types of CLA and not all of them have beneficial effects. The "good" form of CLA is present in dairy foods such as milk and cheese," said Dr John Wallace of the Rowett Research Institute, "but eating lots of dairy foods won't necessarily help our gut health as most of the fats are digested in the small intestine before they get to the large intestine, where most of our gut bacteria are found."

The results of these latest studies showed that several different forms of CLA are produced by gut bacteria. Fortunately, most was of the "good" kind, but Dr Wallace stressed that more extensive studies are needed. One subject produced small amounts of a CLA whose beneficial or otherwise effects are much less clear.

The implications are that, if small quantities of dietary linoleic acid can be delivered to the large intestine, the effects on gut health will be generally beneficial in most people. He added, "The results are of special interest for individuals using anti-obesity treatments that prevent the small intestine from absorbing fats.

This means that those fats - including linoleic acid - will pass into the large intestine and the gut bacteria will produce CLA. It has to be the correct CLA, so it is important to understand how individuals produce different CLA. This must depend on which types of bacteria are present."

More information: The paper, "Differences between human subjects in the composition of th faecal bacterial community and faecal metabolism of linoleic acid" by Dr John Wallace et al is published in the February issue of Microbiology (Vol. 155, part 2, pp. 513-520). mic.sgmjournals.org

Provided by University of Aberdeen

Explore further: Dwindling wind may tip predator-prey balance

add to favorites email to friend print save as pdf

Related Stories

Scientists discover tropical tree microbiome in Panama

11 hours ago

Human skin and gut microbes influence processes from digestion to disease resistance. Despite the fact that tropical forests are the most biodiverse terrestrial ecosystems on the planet, more is known about ...

Bacteria harbor secret weapons against antibiotics

Sep 09, 2014

The ability of pathogenic bacteria to evolve resistance to antibiotic drugs poses a growing threat to human health worldwide. And scientists have now discovered that some of our microscopic enemies may be ...

Recommended for you

Dwindling wind may tip predator-prey balance

Sep 19, 2014

Bent and tossed by the wind, a field of soybean plants presents a challenge for an Asian lady beetle on the hunt for aphids. But what if the air—and the soybeans—were still?

Environmental pollutants make worms susceptible to cold

Sep 19, 2014

Some pollutants are more harmful in a cold climate than in a hot, because they affect the temperature sensitivity of certain organisms. Now researchers from Danish universities have demonstrated how this ...

Research helps steer mites from bees

Sep 19, 2014

A Simon Fraser University chemistry professor has found a way to sway mites from their damaging effects on bees that care and feed the all-important queen bee.

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

fixer
not rated yet Feb 06, 2009
Buteric acid does this too.
How about making them available to the people who need them!
snwboardn
not rated yet Feb 07, 2009
CLA's killing cancer cells is old news, by like 30 years. http://en.wikiped...eic_acid