How is your skin made?
Know its structure and functions. Know Your Skin
The skin is the largest organ of the
body and is made up of multiple layers of cells
that are constantly going through self shedding and
regeneration once every 30 days. The skin is made up
of 3 main layers: Epidermis, Dermis and Subcutaneous
or hypodermis. These layers are held together by the
protein, collagen and elastin fibres. Collagen
provides durability and strength. Time taken for
deepest layer to come to the top is 45-75 days.
The epidermis is the outer layer of
skin. The thickness of the epidermis varies in
different types of skin. It is the thinnest on the
eyelids at .05 mm and the thickest on the palms and
soles at 1.5 mm.
The epidermis contains 5 layers. From
bottom to top the layers are named:
The bottom layer, the stratum basale,
has cells that are shaped like columns. In this
layer the cells divide and push already formed cells
into higher layers. As the cells move into the
higher layers, they flatten and eventually die.
The top layer of the epidermis, the
stratum corneum, is made of dead, flat skin cells
that shed about every 2 weeks
Specialized Epidermal Cells
There are three types of specialized
cells in the epidermis.
The melanocyte produces pigment
The Langerhans' cell is the
frontline defense of the immune system in the skin
The Merkel's cell's function is not
The dermis also varies in thickness
depending on the location of the skin. It is .3 mm
on the eyelid and 3.0 mm on the back. The dermis is
composed of three types of tissue that are present
throughout - not in layers. The types of tissue are:
Layers of the Dermis
The two layers of the dermis are the
papillary and reticular layers.
The upper, papillary layer,
contains a thin arrangement of collagen fibers.
The lower, reticular layer, is
thicker and made of thick collagen fibers that are
arranged parallel to the surface of the skin.
Specialized Dermal Cells
The dermis contains many specialized
cells and structures.
The hair follicles are situated
here with the erector pili muscle that attaches to
Sebaceous (oil) glands and apocrine
(scent) glands are associated with the follicle.
This layer also contains eccrine
(sweat) glands, but they are not associated with
Blood vessels and nerves course
through this layer. The nerves transmit sensations
of pain, itch, and temperature.
There are also specialized nerve
cells called Meissner's and Vater-Pacini
corpuscles that transmit the sensations of touch
The subcutaneous tissue is a layer of
fat and connective tissue that houses larger blood
vessels and nerves. This layer is important is the
regulation of temperature of the skin itself and the
body. The size of this layer varies throughout the
body and from person to person.
The skin is a complicated structure
with many functions. If any of the structures in the
skin are not working properly, a rash or abnormal
sensation is the result. The whole specialty of
dermatology is devoted to understanding the skin,
what can go wrong, and what to do if something does
These are fat cells that conserve
body heat while protecting other organs from injury.
They provide a cushioning effect and are a source of
energy in lean times.
Thickness of layer varies - the
thinnest layer is on our eyelids making them light
and flexible, the thickest is on our hands and feet
Functions of Skin
This skin provides a protective layer
for organs and tissues from pathogens, heat and
light. It regulates body temperature. It stores
water, fat and Vitamin D and has touch receptors
that sense pain or pleasure. Skin is an excretory
and absorption organ.
Skin has a natural moisturising
factor (NMF). Teen skin is prone to oiliness as
hormones are regulating. At 20-30 years skin cell
turnover provides optimum condition. At 30-40 years
cell turnover starts to decrease and fine lines
start to appear. At 40-50 years skin becomes more
dry. Over 50 years of age, cell turnover drops by
50% resulting in flaky patches and deeper lines.
The skin may be sensitive. Sensitive
skin reddens easily due to environmental changes or
cosmetic products. Skin can become permanently
sensitive due to allergy, shaving, and use of skin
care productscontaining alpha hydroxy and retinoic
Skin has several jobs
It holds the body together
It stops water and body fluids from
leaking out of the body.
It stops germs and dirt from
getting into the body.
It senses how things feel (touch).
It can sense the temperature of
It can tell you when you have been
It is waterproof so that rain
TYPES OF SKIN
Skin can be divided into various types according to
its texture. It is essential to know the various
types of skin, so that its treatment can be done
It has a fine even texture with a supple and smooth
surface. It has a proper balance between oil and
moisture contents and is therefore moist and neither
greasy nor dry. It looks clear and does not develop
spots and blemishes. The pores of the skin are fine
and barely visible. It reflects good health and
needs gentle treatment.
Dry skin has a dry parched appearance and has a
tendency to flake easily. It is prone to wrinkles
and lines. It is due to the inability to retain
moisture as well as the insufficient production of
sebum by the sebaceous glands. Dry skin often has
problems in cold weather and ages faster than normal
or oily skin. Constant protection is very important.
It needs a moisturiser during the day and a good
cream at night.
This type of skin is caused by the over secretion of
sebum making the skin surface oily. The excess oil
on the surface of the skin attracts dirt and dust
from the environment. oily skin is also prone to
black heads, white heads, spots, pimples and such
skin will never be clear. This type of skin needs to
be cleansed thoroughly.
This type of skin is very common. As the name
suggests, it is a combination of both oily and dry
skin with certain areas of the face oily and the
rest dry. Usually there is a Central greasy panel
consisting of the forehead, nose and chin and a dry
panel consisting of cheeks and the areas around the
eyes and mouth. The greasy central panel is referred
to as T - Zone. In such cases, each part of the face
should be treated accordingly - the dry areas as for
dry skin and the central panel as for oily skin.
This type of skin has a fine texture and is very
sensitive to changes in the climate. They show the
disadvantage of bleaching, Waxing, threading etc.
Choosing Your Skin Type
best way to get the most out of your natural skin
care products is to choose them on the basis of your
There are four basic skin types:
oily, normal, dry and sensitive. When it comes to
the skin of the face and neck, most people have a
combination of two or more of these, so when
choosing your skin care products consider how each
product is going to affect your skin.
to choose your skin type
Normal / Dry
Normal / Oily
enlarged, especially on nose
occasional or often
occasionally. Tends to rashes
and reacts often
develops an oily sheen
throughout the day
seldom a problem
seldom burns or readily burns
tans easily and generally does
readily burns and becomes
soft and supple
red, irritated, flaky and itchy
many around mouth and eyes
Take the tests to see if you
have any problems with your skin
Run a pencil over your cheeks and
neck with gentle force, if this results in reddening
or swelling, you have very sensitive skin.
Press a small mirror against various
parts of your face, if you have a dry skin, only a
very slight touch of grease will show on the mirror
surface, With combination skin, more grease will
show when using the mirror on the middle part of the
face. Greasy skin is recognizable by obtaining
greasy spots from the cheeks.