Skin Facts and Functions

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Skin Facts and Functions

Interesting Skin Facts:
  • Skin is a vital organ that covers the entire outside of the body, forming a protective barrier against pathogens and injuries from the environment.
  • The skin is the human body's largest organ, both in weight and surface area. Thickness varies from 0.5 mm to 5 mm thick or more and weighs approximately 6 pounds.
  • Fresh skin cells come to the surface every 20 to 28 days, as they push the dead skin layers off the skin surface.
  • The skin renewal process slows down with age.
  • Aging skin also loses collagen and elasticity.
Skin's Primary Functions:
  • Protection: The skin protects from ultraviolet (UV) light, abrasions, infections (eg, bacterial or fungal), chemicals, and excess water.
  • Sensation: The skin is the largest sensory organ with a wide range of receptors for touch, pressure, temperature, and pain.
  • Temperature regulation: The skin warms the body through a thick layer of adipose tissue and hair. The body is cooled through sweat glands.
  • Metabolic functions: The skin synthesizes vitamin D, which assists bone formation. Underneath the skin, adipose tissue acts as an energy warehouse.