The new ”organ” is called the interstitium and is the tissue that lines our digestive tracts, lungs and urinary systems, surrounds the arteries and veins and supports the tissue between our muscles.

(Jill Gregory/Mount Sinai Health System)

Scientists have long known about this tissue but its importance was never really understood.

Experts at New York University’s School of Medicine say it’s time to re-think the ”previously unappreciated” tissue that can shrink and expand, sort of like shock absorbers, transports fluids within organs and around the body.

Researchers say because of its ”dynamic” role in these and many other functions, they feel the interstitium should be called an organ.

Their findings are in the journal Scientific Reports.