Body & HealthFact

Your outer skin is never more than a few weeks old.

The epidermis renews itself roughly every 4 to 7 weeks. New cells form in the deepest layer, migrate upward, harden with keratin and are shed as dead flakes, about 1 to 2 grams a day. That way you lose around half a kilogram of skin every year without noticing. At about 2 square metres, skin is your largest organ.

Useful: That is why a scratch that only reaches the epidermis heals without a scar.

Source: en.wikipedia.org

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