Scientists May Have Just Discovered a New Organ—And It Could Be the Biggest Yet


A new study published in Scientific Reports boldly proclaims that researchers from NYU School of Medicine and Mount Sinai Beth Israel Medical Center, both in New York City, have identified a new organ in the body, thought to be the biggest organ of them all. Called "the interstitium," what has long been thought to be merely tough, dense connective tissue running throughout the body—beneath the skin, the visceral organs, around arteries and veins, and in the fascia tissue between muscles—is really a network of fluid-filled compartments whose structure easily defies viewing by traditional methods, the researchers say.

When asked how researchers can call something found in numerous parts of the body an organ, Neil Theise, co-author of the study, and professor of pathology at NYU School of Medicine, tells Mental Floss that it satisfied both definitions of an organ, being "a tissue that is unitary in structure" that has "a unitary set of functions." It might more accurately be called "an organ system" similar to the cardiovascular system and the lymphatic system.

In all of the places that it's found, the interstitium's fluid-filled compartments (which are the source of lymph, a fluid central to immune cell function) are surrounded by bundles of collagen and elastin—strong and flexible connective tissues that seem to form a sturdy framework for the compartments.

They have the "same cell types, same sort of structure [and] architecture, and the same relationship with the lymphatic system wherever they're found," Theise says. This makes sense, because the compartments drain directly into the lymphatic system. This might explain why cancer cells that get into the lymph nodes spread so rapidly.

This connection to the lymphatic system is also interesting because the last time scientists discovered a new part of the body, it too was connected to the lymphatic system: a system of vessels called the "central nervous system lymphatic vessels," which drain lymphatic fluid from the brain to the surrounding lymph nodes.

They believe the interstitium compartments act as a shock absorber that protects organs from tearing as they squeeze and pump during their daily functions. Moreover, since collagen bundles in lab settings are shown to generate electrical current, they suspect the same thing is happening within the compartments as organs and muscles bend and move. Theise thinks this might account for some of the responses people have to alternative medical treatments like acupuncture and myofascial release, which involves applying sustained pressure to myofascial connective tissue to relieve pain.


Prior to this study, Theise says, the literature describing this interstitial space—often called "the third space" after the cardiovascular and lymphatic systems—has been vague. Part of the problem is that the structure of the interstitium can't be viewed when it's flat—and that's generally how it's been seen. When scientists prepare tissue to put onto slides for viewing under a microscope, they use chemicals to remove the fluids from it, and slice it thinly, causing the normally fluid-filled interstitial compartments to collapse.

Researchers had noticed "cracks" between collagen fibers in fixed slides, but, Theise says, they were always told these were just "artifacts of having torn the tissue."

However, in the fall of 2015, researchers from Mount Sinai Beth Israel Medical Center discovered the true shape of the interstitium by accident when testing out a new technology called probe-based confocal laser endomicroscopy, which offers a microscopic view of living tissue. In this procedure, a thin, camera-bearing probe called an endoscope is snaked down a patient's throat, where scientists can view the insides of organs with a laser that lights the tissues, and a sensor that analyzes the reflected light. There, while scoping a patient's bile ducts, the researchers, who are co-authors on the current paper, saw something they'd never seen before: the interconnected, fluid-filled compartments.

The discovery opens numerous avenues for research. Theise's team will most immediately use the research to look at a rare liver disease they now think may begin inside the interstitial compartments. Next, they'll be gathering all the bits and pieces of information they have on the interstitium for a comprehensive literature review, Theise says, "organ by organ, cell by cell, and disease by disease."

Wayfair’s Fourth of July Clearance Sale Takes Up to 60 Percent Off Grills and Outdoor Furniture


This Fourth of July, Wayfair is making sure you can turn your backyard into an oasis while keeping your bank account intact with a clearance sale that features savings of up to 60 percent on essentials like chairs, hammocks, games, and grills. Take a look at some of the highlights below.

Outdoor Furniture

Brisbane bench from Wayfair

- Jericho 9-Foot Market Umbrella $92 (Save 15 percent)
- Woodstock Patio Chairs (Set of Two) $310 (Save 54 percent)
- Brisbane Wooden Storage Bench $243 (Save 62 percent)
- Kordell Nine-Piece Rattan Sectional Seating Group with Cushions $1800 (Save 27 percent)
- Nelsonville 12-Piece Multiple Chairs Seating Group $1860 (Save 56 percent)
- Collingswood Three-Piece Seating Group with Cushions $410 (Save 33 percent)

Grills and Accessories

Dyna-Glo electric smoker.

- Spirit® II E-310 Gas Grill $479 (Save 17 percent)
- Portable Three-Burner Propane Gas Grill $104 (Save 20 percent)
- Digital Bluetooth Electric Smoker $224 (Save 25 percent)
- Cuisinart Grilling Tool Set $38 (Save 5 percent)

Outdoor games

American flag cornhole game.

- American Flag Cornhole Board $57 (Save 19 percent)
- Giant Four in a Row Game $30 (Save 6 percent)
- Giant Jenga Game $119 (Save 30 percent)

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30 Pungent Facts About Farts

This man is clearly not trying to hide the fact he just passed gas.
This man is clearly not trying to hide the fact he just passed gas.
BrilliantEye/iStock via Getty Images

Whether you openly admit it or desperately try to hide it, it’s an undeniable fact that every living and breathing human being farts. And while passing what you thought was going to be silent gas only to be wrong in certain situations can definitely be embarrassing, there’s something undeniably humorous about flatulence—no matter your age.

If you do love a good fart joke, you’re in good company. The very first recorded joke, which was written by the Sumerians and dates all the way back to 1900 BCE, was about—you guessed it—breaking wind. And some of the world's great thinkers, from William Shakespeare to J.D. Salinger, have slipped a fart joke (or 10) into their work.

In this episode of The List Show, we're sniffing out 30 fascinating facts about farts—from why humans expel gas to how often the average adult squeezes the cheese. You can watch the full episode below.

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