The Importance of the Appendix

The human appendix, a narrow pouch that projects off the caecum in the digestive system, has long been known as a vestigial organ with unknown function. It is largely ignored until it gets inflamed (causing appendicitis) when it can cause high fever and a lot of pain leading, usually, to surgical removal. However, this has always puzzled me, knowing the intelligence of the body, why it would continue to sustain a defunct organ with the energy expenditure that entails? It seems the answer is that it could have a function to do with immunity.

Recent research on comparing different species morphology has “found that species with an appendix have higher average concentrations of lymphoid (immune) tissue in the caecum. This finding suggests that the appendix may play an important role as a secondary immune organ.”[i] Indeed, it may serve as a reservoir for beneficial gut bacteria and removal would therefore be potentially problematic as it would reduce our capacity to keep our gut microbiome balanced. This exciting new research is based on a comparison of different species and is not related to humans alone, but it does have implications for avoiding surgical removal in the future, if this discovery is supported by human studies.

Keep yourself informed and your gut healthy (with a diverse gut flora) should help minimise problems and hopefully surgical removal should become something belonging to medical history.

p.s. there could be a similar fate awaiting gall bladder surgery – also not necessary if fat digestion is not compromised.


[i] Smith, Heather et al (2017). Morphological evolution of the mammalian cecum and cecal appendix. Comptes Rendus Palevol,; 16 (1): 39.