Skin and Hair

Human Skin

• The skin is the largest organ in our body (1^✔ ✔Trusted Source
  Skin explained
  
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•  The human skin contains 45 miles of nerves.
• There are 3 million cells in one square inch of skin.

Weight of the Skin

• Our skin weighs around one-seventh of our total weight and is the largest and heaviest organ in our body (2^✔ ✔Trusted Source
  How does skin work?
  
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• The total weight of skin in an average human adult is 61 pounds.

Nail Growth

• Fingernails grow faster than toenails (3^✔ ✔Trusted Source
  Clinical Methods: The History, Physical, and Laboratory Examinations
  
  Go to source). The nails of the toes and fingers take about 6 months to grow from base to tip (4^✔ ✔Trusted Source
  Understanding the Formidable Nail Barrier: A Review of the Nail Microstructure, Composition and Diseases
  
  Go to source).

Receptors

• There are 100 receptors at each of our fingertips.
• The human skin contains 280,000 heat receptors.

Fastest Growing Tissue

• Next to the bone marrow, hair is the fastest-growing tissue in the body (5^✔ ✔Trusted Source
  Low-Level Laser (Light) Therapy (LLLT) for Treatment of Hair Loss
  
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Thick Skin Vs Thin Skin

• The thickest skin is found on your feet, whereas the thinnest areas of skin are your eyelids (6^✔ ✔Trusted Source
  Anatomy, Skin (Integument)
  
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Sweat Glands

• Our feet contain about 250,000 sweat glands.
• The palms of the hands and soles of the feet contain more sweat glands than other parts of the body (7^✔ ✔Trusted Source
  Physiology of sweat gland function: The roles of sweating and sweat composition in human health
  
  Go to source).

UV Radiation and Sun Exposure

• About 80% of the ultra-violet rays from the sun can get through the cloud and can cause sunburn or tan even on a cloudy day (8^✔ ✔Trusted Source
  Comprehensive review of ultraviolet radiation and the current status on sunscreens
  
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Color of the Skin

• Melanin, a pigment present in the skin is responsible for the color of the skin of a person (9^✔ ✔Trusted Source
  The structure of people's hair
  
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Outermost Layer of the Skin

• The epidermis, the outermost layer of the skin, renews itself constantly on its own (2^✔ ✔Trusted Source
  How does skin work?
  
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Dead Skin Cells

• Every minute, 30,000 to 40, 000 dead skin cells fall from our body.

Human Hair

• Adult human hair can grow up to a length of approximately 90cm (9^✔ ✔Trusted Source
  The structure of people's hair
  
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• The life span of hair is two to seven years (10^✔ ✔Trusted Source
  Aging changes in hair and nails
  
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• On average, the human scalp has 100,000 hairs (11^✔ ✔Trusted Source
  Advances in hair growth
  
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• A hair grows by 0.35 mm per day, 0.5 inches per month and 6 inches per year (12^✔ ✔Trusted Source
  Anatomy, Hair
  
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• 100 hairs are likely to fall every day (13^✔ ✔Trusted Source
  The Diagnosis and Treatment of Hair and Scalp Diseases
  
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Hair Follicles

• Circular hair follicles produce straight hair, whereas oval follicles make curlier hair (14^✔ ✔Trusted Source
  Trichonodosis
  
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• Goosebumps arise when tiny muscles called arrector pili muscles in our skin's hair follicles pull hair upright (15^✔ ✔Trusted Source
  What goosebumps are for
  
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Color of the Hair

• The color of our hair is determined by melanin, a pigment present in the human body (16^✔ ✔Trusted Source
  Is hair color determined by genetics?
  
  Go to source).

Ability of Hair

• A single strand of hair has the ability to support up to 100 grams of weight, and all the hair has the ability to support up to 12 tones of weight.