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As your body’s biggest sensory organ, skin keeps you in touch with the world. The skin of an average adult male weighs nine pounds and covers about 20 square feet. That’s as much space as the floor of a very big closet, or the top of a dining table.
Skin keeps fluids inside your body and infections outside of it. It tells you if you’re too hot or too cold, warns you when some dangers are near, and lets you feel the affection of loved ones. People have survived without the use of eyes, ears, nose, or tongue. But the skin is essential.
