Move over skin, there's a new largest human organ in town, and it comes with a fancy name to boot: the interstitium. This newfound organ has been identified for the first time by researchers from New York University's School of Medicine, who just published a study in the journal, Scientific Reports, detailing its anatomy and functions.
The paper defines the newly discovered organ as a "fluid-filled space within and between tissues" that spreads throughout the body and can be found nearly everywhere: under the skin, between our organs, around arteries and veins, along the fibrous tissue between muscles, and even around the digestive tract and urinary system.
Medicine is already acquainted with interstitial tissue (the tissue found between our cells) and interstitial fluid (the liquid that fills the space between the cells), but the interstitium ties everything together in a network of fluid-filled compartments strung together by collagen and elastin, the study explains.
Co-senior author, Dr. Neil Theise, a pathologist at NYU Langone Health in New York, points out that the interstitium may actually be the largest organ in the human body.
"I think it's bigger than the skin," Dr. Theise told CNN.
He estimates the interstitium makes up 20 percent of the body's volume, "which is equivalent to about 10 liters in a young adult."
By comparison, the skin — until now considered to be the largest human organ — only holds about 16 percent of the body mass.