Mirror mirror how I look? Is something we ask every day? But have you ever asked; skin; the organ we are all obsessed with; as to- who you are, what are you made of, how do you help us, what factors affect you, etc etc..
Well if not, then today I will share the basic information about human skin.
WHAT IS SKIN?
It is the largest organ of human body which covers the entire external body surface and accounts for around 16% of the body weight.
Skin is a dynamic organ in a constant state of change, as cells of the outer layers are continuously shed and replaced by inner cells moving up to the surface.
WHAT IS THE STRUCTURE OF SKIN?
There are three structural layers of the skin namely:
EPIDERMIS: the epidermis is the outermost layer of the skin, serving as the barrier between the interior body and exterior environment.
- The epidermis varies in thickness from thinnest (0.05 mm) on the eyelids to thickest (0.8±1.5 mm) on the soles of the feet and palms of the hand.
- The epidermis is further divided into 4-5 layers, the bottom most layer of the epidermis has cells that divide and push already formed cells into higher layers.
As the cells move into the higher layers, they flatten and eventually die. The top most layer of the epidermis is thus made up of dead, flat skin cells that shed about every 2 weeks and it is this that gets removed when we scrub our face.
- The main cells of the epidermis are the keratinocytes (which synthesise the protein keratin) and melanocytes (which produces the pigment melanin).
DERMIS: The dermis is found below the epidermis.
- It is a thick layer of fibrous and elastic tissue (made mostly of collagen, elastin, and fibrillin) that gives the skin its flexibility and strength.
- The dermis contains nerve endings, sweat glands and oil (sebaceous) glands, hair follicles and blood vessels.
HYPODERMIS: The hypodermis lies below the dermis and is the innermost layer.
- It is made up of loose connective tissue and majorly fat.
- The fat cells help insulate the body from heat & cold, provide protective padding and serve as an energy storage area.
- The thickness of this layer varies depending on the place in the body and from person to person.
WHAT ARE THE MAJOR FUNCTIONS OF SKIN?
1.) PROTECTION of the body: skin provides a protective barrier against mechanical, thermal and physical injury.
- The outermost portion of the epidermis; known as the stratum corneum; is relatively waterproof and; when undamaged; prevents most bacteria, viruses, and other foreign substances from entering the body.
- Melanin (the pigment found in skin) protects against harmful UV radiations coming from the sun.
2.) PREVENT LOSS OF MOISTURE from the body: our skin acts as a barrier to prevent the loss of water and necessary body fluids from the body.
3.) REGULATE BODY TEMPERATURE: retention or release of heat; depending on outside body temperature. This is brought about by sweat glands and blood flow regulation.
4.) IMMUNOLOGICAL SURVEILLANCE from microorganisms: certain cells in the skin work closely with the immune system to fight off bacteria, viruses and other nasty things that land on your skin. The skin prevents them from getting into your body and making you sick.
5.) EXCRETION OF WASTE PRODUCTS from the body: some wastes are excreted through the skin, such as urea, water, uric acid and ammonia along with sweat. This helps rid your body of the things that might make you sick if your skin didn’t serve as a gateway to the outside.
6.) SENSATION: the nerve endings in the skin identify five different kinds of sensations: heat, cold, pressure, pain and contact. This means you can react to hot or cold, to pain or injury, and even to a gentle touch in the appropriate manner.
WHAT FACTORS AFFECT THE SKIN?
a) Biological factors: genes and genetics.
b) Intrinsic factors: stress, vitamin deficiency, improper nutrition, sleep deprivation, hormones, alcohol, smoking and various medical conditions.
c) Extrinsic factors: sun/UV ray exposure, free radicals, smoke & other air pollutants, harsh weather conditions, poor maintenance and misuse of products.
d) Mechanical: regular beauty procedures, facial expressions, sleeping positions, and gravity.
WHAT ARE THE MOST COMMON SKIN CONDITIONS/ DISEASES?
- SUN BURNS
- VITILIGO/ LEUCODERMA
- DERMATITIS (Atopic and Contact)
- MACULAR AMYLOIDOSIS
- FUNGAL INFECTIONS (Skin, Scalp and Nails)
- RASH/ ALLERGY
- INSECT BITES
- PITYROSPORUM FOLLICULITIS
- MOLLUSCUM CONTAGIOSUM
- CORNS/ CALLUS
- CHICKENPOX (Varicella)
- SKIN CANCER