How Much Does Your Skin Weigh?

Tyler Olson | Dreamstime

You might guess the brain or lungs -- or some other hefty internal organ -- but you'd be off by a large margin. And that's because the heaviest organ is not one that most people would consider an organ at all, nor would one expect it to be so heavy.

We're talking about your skin.

The skin consists of three layers: the epidermis , dermis and subcutaneous tissue. The thickness of skin varies greatly throughout the body. For example, the delicate skin around your eyes is only as thick as a few sheets of paper; the pads on your feet are about as thick as a pencil eraser. It may have different characteristics in many areas, but it's all one organ.

But skin isn't all "fleshy" stuff. As an organ, skin is made up of everything that covers one's body, including the nails and hair . In total, skin accounts for about 16 percent of a person's total body weight.

Most adults' skin weighs in at 20 pounds or more. Of course, the weight of skin varies depending on its owner, with skinnier people 's skin weighing less than their heavier brethren. If you were to tear off and spread out the average adult's skin, it would cover approximately 22 square feet (2 square meters).

After the skin, here are the five heaviest organs in the body:

Intestines - 7.5 pounds (4 pounds for the large intestine, 3.5 pounds for the small)

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Follow Remy Melina on Twitter @RemyMelina

Remy Melina was a staff writer for Live Science from 2010 to 2012. She holds a bachelor’s degree in Communication from Hofstra University where she graduated with honors.