What does the appendix do? A lot more than we thought…

If someone mentions their appendix, you might also expect to hear “had to be removed” and “useless thing anyway,” but new research suggests it might not be as pointless as once thought.

Published: December 3, 2015 at 12:00 am

If you hear someone mention their appendix, you might expect the words “had to be removed” and “useless thing anyway” to follow. But new research by scientists in Australia and France suggests that this little-appreciated part of your gut might not be quite as pointless as once thought.

Their study, published in Nature Immunology, shows that the appendix may in fact act as a reservoir for ‘good bacteria’. These bacteria contribute to keeping the gut healthy and helping you recover from infections. The study’s findings contradict a commonly held belief that the appendix has no function.

The appendix is a cul-de-sac of a tube attached to your colon. Most people only become aware of it if it becomes inflamed, requiring an emergency operation to remove it.

But in this study, researchers showed that a group of white blood cells called innate lymphoid cells (ILCs) help the appendix play a role in the body’s immune response to infection.

"We've found that ILCs may help the appendix to potentially reseed 'good' bacteria within the microbiome -- or community of bacteria -- in the body,” explained Gabrielle Belz, a professor at Melbourne’s Walter and Eliza Hall Institute. “A balanced microbiome is essential for recovery from bacterial threats to gut health, such as food poisoning."

Without this balance, she said that some people are faced with the unpalatable option of restoring populations of good bacteria by ‘faecal transplant’. (And yes, that means what you think it means, albeit with a bit of cleaning and straining of the faeces in between.)

Around 40,000 people in the UK are hospitalized with appendicitis each year, and appendix removal is one of the country’s most common surgical procedures.

Although removing it is not thought to be harmful, if it’s a part with a purpose, it certainly requires more research, said Belz.

“We may wish to rethink whether the appendix is so irrelevant for our health.”