GioNails: Anatomy of the Nail

Good morning dear NPAs!

Today's post is different. It's been a while that I want to make a post talking about the anatomy of the nail, out of personal curiosity, to spread the information among the new NPAs that just entered our colourful world; and also for those who are already around and would like to know a bit more about this part of the body we love so much! Be ready because it's a long post, but I think it's worth reading!

The nails are made of a hard protein called keratin and consist of:

Free margin or distal edge: is the anterior part of the nail plate corresponding to the abrasive or cutting edge of the nail.
Matrix: is the tissue which the nail protects. It is the part of the nail bed that is beneath the nail and contains nerves, lymph and blood vessels. It’s the only part of the nail that is alive.
Eponychium or cuticle: is the small band of epithelium that extends from the posterior nail wall onto the base of the nail.
Paronychium: is the border tissue around the nail.
Hyponychium: is the epithelium located beneath the nail plate at the junction between the free edge and the skin of the fingertip.
Nail plate: is the hard part we think about when we say the nail, made of translucent keratin protein.
Nail bed: is the skin beneath the nail plate. It's made of two types of tissues: the deeper dermis, the living tissue which includes capillaries and glands; and the epidermis, the layer just beneath the nail plate, which moves toward the fingertip with the plate.
Lunula: is the visible part of the matrix, the whitish crescent-shaped base of the visible nail. Also called small moon.
Nail wall: is the cutaneous fold overlapping the sides and proximal end of the nail.

The nail is made of 3 layers:

Superficial layer: formed by devitalisation of cells (the cells lose their nucleus and accumulate keratin) which come from the matrix.
Intermediate layer: it's the thickest and has the same origin as the surface, but with much more living cells joined together and with lower density of keratin fibers.
Deeper layer: only 2 layers of cells that come from the epidermis bed.

In principle, the nails are not very susceptible to fungal infections, but they can happen very easily when they are damaged by trauma or even manipulations of the nail and cuticle; between the skin and the cuticle is a small epithelial fold called proximal fold, that protects the nail matrix. The cuticle protects the area between the nail and this proximal fold from the exposure to bacteria. The cuticle should not be cut or pushed back. This makes the nail more vulnerable to paronychia, a painful infection that can last several months. Besides, to damage the cuticle will not prevent loose skin of ingrown toenails.

Changes in color, in shape and texture of the nails can indicate health problems:

Whitish spots: anaemia, zinc and proteins deficiency, contact dermatitis (allergy to nail polish, soaps, detergents, etc…), psoriasis, fungal infections, heavy metal poisoning, renal failure.
Yellow spots or yellowish nails: common in smokers, also indicate the chronic use of antibiotics, excess intake of beta-carotene (precursor of vitamin A, found in carrots, beets, papaya…), diabetes, mycoses and liver ailments.
Purplish: mycoses, tumors, use of coagulant medications, cardiac ailments, lupus erythematosus.
Greenish or swelling, redness and pain that spreads around the fingers: bacterial infections and mycoses.
Half White half reddish: kidney problems.
Black stripes: hormonal disorders, fungal infections, tumors in the nail matrix, skin cancer (melanoma).
Weak, dry, brittle, prone to flaking: lack of calcium, besides zinc and vitamins A, which are the nails nutrients. Anaemia, hypothyroidism.
Yellowish, thickened and without growth: pulmonary disorders
Ripples that become apparent even with two layers of nail polish: generally indicate trauma (the cuticle pushing spatula is used with strength). And also: anaemia and heart or lung disease.

If the bad appearance is only from aesthetic origin, the use of moisturizers for the nails helps a lot, as well as the habit of always washing the hands with cold or lukewarm water not to dry the skin. Another good tip is to perfect the nutrition. Eating whole grains and nuts (rich in zinc), and eggs and lean meats (protein sources) enhances the formation of keratin. The ideal is to eat two daily portions of these foods. And the freshest, the best.

I would like to add the knowledge I acquired in 1 year and 7 months of blogging:

It is extremely important not to trim the cuticles in any way. The argument that the nails need to "breathe" between manicures is a myth, because the only living part of the nail is the matrix. The nail polish penetrates the first layer of keratin and protects the nail against friction. In the other hand, this interval between manicures is good for the cuticles, which are always in contact with the chemical compounds present in the polishes. For those who had or still have problems with the cuticles (like me), leaving a gap between the polish and the cuticles is very useful, but only if done in a natural way, which means not letting the brush touch the cuticles.

Avoid using your fingernails as tools to pick up or open things. Avoid contact with cleaning products, always using rubber gloves when working with water. And if you do not want to paint your nails, at least keep them with a clear base coat to protect them from daily friction (like when we look for something inside the purse).