What your appendix does for you

Finger-sized and dangling off the bottom of the right side of the large intestine, the appendix is a worm-shaped, blind ended tube that forms part of the human gastrointestinal tract. Long dismissed as of little clinical consequence or use to modern man, most of us ignore it until it occasionally goes wrong and ends up being removed by a surgeon. Indeed, we’ll talk to one about that shortly.

But, more recently, scientific research has begun reappraising this enigmatic organ. It is now believed that it performs potentially valuable roles in the body - including as a reboot-refuge for friendly bacteria, and it might even serve to protect us from a serious infection and even Parkinson’s Disease. On the other hand, some studies claim it might even be a risk factor for Parkinsons.

Either way, we need to look more closely. So, today, we’re going to be doing our own biopsy on the appendix. What is it? How did it evolve? What’s its role? And what might be the consequences of taking it away?

To kick us off, here’s the science writer and author of Growing Young, Marta Zaraska. She recently wrote a fascinating piece in Medscape about why it might be time to completely reconsider what we know about this fascinating organ…

Marta - I think it caught my attention, this story, because I don't have an appendix myself, and it was something that I completely disregarded in the past. So whenever I would go to see a doctor and they would ask me whether I had any surgeries in the past, I would say that I did indeed have an appendectomy, my appendix removed, when I was 17. But really, what does it matter, right? It's been such a long time and it's not an issue. It's gone. It doesn't matter. Then I came across a research paper that was actually a study done by French researchers on primates in a French zoo, and they discovered that the primates that had an appendix actually suffered much fewer episodes of diarrhoea. And it really caught my attention because it said that, you know, there was something to the appendix that was actually important, and here I was not having one. So I started digging into research and then I came across another paper by the same group of researchers from France that showed that mammals that have an appendix actually live longer. And I started reading more and more papers, and indeed I found all those connections between appendix and plenty of different conditions such as Parkinson's disease, colon cancer, ulcerative colitis, even allergies in children.

Chris - Has this been a recent kind of flourishing interest in the appendix, or have scientists been looking at this for a long time and, because it was regarded as a bit backwater-y, people didn't pay much attention.

Marta - I mean, scientists have been looking at the appendix for a very long time. Indeed it was discovered in the 16th century by an Italian surgeon, but it took a very, very, very long time for us to realise that the appendix actually had a function. And this is a very recent change in perspective because even Darwin thought that the appendix is completely useless. He basically thought it was some kind of remnant of our past. When our ancestors switched our diets from eating leaves to fruits. Some physicians went so far, there was this American physician in the early 20th century called Miles Breuer, that actually suggested that people who have an appendix are some kind of inferior. And those who have an infected appendix, like I did myself, should be left to perish because their inferior DNA should be removed from the gene pool. And this view has only very recently begun to change. I've actually even stumbled upon a paper from 2019 that still said that appendix was basically a useless organ.

Chris - We used to be a bit more gung ho, medically, didn't we? 'If in doubt, chop it out' was one of the things that surgeons used to sometimes say. Is it now that we are beginning to say then, well, maybe we should be a bit more conservative and a bit more minimally invasive maybe, rather than just default straight to surgical options. Are doctors increasingly beginning to question maybe treating it with antibiotics and letting an appendicitis settle down before we go in with the scalpel?

Marta - I mean, definitely there have been some very big studies done recently that do show that in certain cases antibiotics may be enough. Of course, it's not always the case and in more severe cases you have to have your appendix removed. But certainly just assuming that, if it's infected it has to come out, is no longer seen as a given. So the view is definitely changing here. You know, in North America there are about 400,000 cases of appendicitis every single year. So there are lots of appendixes being removed each year. Some of them might have perhaps been cured simply with antibiotics. So definitely there is a change in perspective right now that it doesn't always have to come out.