Meet your 'newest' organ – the mesentery

A neglected membrane in the digestive tract may in fact be an undiscovered organ, a surgeon has claimed.

Professor J Calvin Coffey of the University of Limerick says the mesentery, a humble two-walled sheet of fatty membrane which holds the intestines in place, has been unfairly overlooked as the 79th organ in the human body, reports the Washington Post.

According to Coffey, the mesentery is a continuous structure and not a disjointed series of tissues as has been thought for more than a century.

Subscribe to The Week

Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.

SUBSCRIBE & SAVE

Sign up for The Week's Free Newsletters

From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.

From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.

Sign up

"Without it you can’t live," says Coffey. "There are no reported instances of a Homo sapien living without a mesentery."

Although vital organs such as the heart, brain and lungs get most of the press, the human body has 78 organs. The mesentery would be the 79th, although it is unclear who has the last word on classifying it as such.

"That's a fascinating question. I actually don't know who the final arbiter of that is," Coffey told Discover magazine.

Leonardo da Vinci knew of the mesentery in 1508, The Independent reports, but little attention has been paid to it until recently.

An update to the medical textbook Gray's Anatomy in 2015 shows the membrane to be a single, folded-over band of tissue stretching from the pancreas through the small intestine and colon. It wraps around these organs, helping to hold them together and maintain their structure, although it is unclear what it does precisely, says The Smithsonian.

Coffey is optimistic that further study could reveal more about its function, as well as help improve treatment of gut illnesses such as Crohn's disease and irritable bowel syndrome.