More Than Just Nails

Leilani W
Apr 1
8 min read

Whether it’s scratching an itch, flipping through pages, or adding a touch of color, our nails are involved in more of our daily routines than we realize. Most people don't give much attention to their nails. You might see people frequently scrolling for inspiration for their next polish job, but not often do we wonder what our nails are trying to show us. Today, to answer some mysteries of this highly used tool, we'll look at what nails even are and why we have them, their structure, conditions and signs of concern, and treatments and prevention for lasting health.

What are Nails?

As you may know by now, nails are the things found at the tips of your fingers and toes. They are part of our integumentary system (the body’s outer layer). More specifically, though, nails are structures made from 3 layers of nonliving keratin cells (which is why you can cut your nails). Keratin is a protein with amino acids that help keep your nails healthy and strong. Water and lipids can also be found in nails to prevent dryness and fragility. In comparing fingernails to toenails, fingernails grow at a much faster rate, with about 3 millimeters per month, while toenails grow about 1.5 millimeters per month.

Why do we have Nails?

Fingernails are essential for protecting the fragile skin layer underneath including blood vessels and nerves from injury and infection; enhancing the sense of touch (several nerves are under the nails, making injuries very painful); and serving as a tool for everyday tasks such as scratching, picking up small objects (the many blood vessels maintain blood flow even when gripping things tightly), or flipping through a book. Toenails mostly function to protect the toes, which are pretty vulnerable to injuries such as stubbing.

Structure

The nail plate is the largest visible part of the nail, where you get painted or shaped at nail salons. It is formed by layers of keratin that originate from the nail’s matrix (more on this soon). If you look very closely at this hard, slightly curved surface, you’ll see very small vertical ridges that are unique to you. The white tip that you see at the end of each nail is the free edge, which you can cut/trim. Majority of where this plate originates from is the nail matrix, a part that is mostly hidden under the nail plate; some people’s lunula (the visible white/lighter shade, half-moon shaped section) is visible, while others’ isn’t; you can see it at the base of some nails. The matrix, being the nail’s growth center, produces keratin that is gathered and pushed slowly forward, causing a nail to grow. Any damage to this area can cause permanent issues. Covering the matrix is the mantle. The mantle is the skin that acts as a protective barrier for the matrix and aids in nail health, making any damage to the mantle problematic for nail growth.

The nail bed, as the name suggests, is the bottom part where the nail is laid on top of. It’s composed of blood vessels, nerves, soft tissue, and skin under the nail plate, which firmly attach it (except for the tip of the finger or toe, which we use as a tool for the earlier mentioned tasks).

The nail folds, lateral and proximal, are located around the nail and serve as borders that provide protection and support. The lateral nail fold is the skin on the sides of the nail; it helps protect the edges of the nail plate from any external damage and guides nail growth. The proximal nail fold, the skin bordering the bottom of your nail, protects the nail matrix from trauma, ultraviolet light that could cause cancer, and any other irritants that could affect nail growth. Also found at the base of the nail are the cuticle and eponychium. These two structures are often mixed up. Essentially, the cuticle is the thin layer of dead tissue that grows from the nail bed and attaches directly to the nail plate. Although you can trim it or push it back, as most nail stylists do before manicures, this can harm your nail health because the cuticle is there for further protection of the nail matrix. The eponychium is the living tissue connected to the nail plate that is between the proximal fold and the cuticle. The eponychium shouldn’t be cut or trimmed, and it’s another seal against foreign irritants.

Going back up to the top of your nail, we’ll see the hyponychium and onychodermal band under the free edge of the nail plate. Both prevent bacteria and debris from entering under the nail bed and act as barriers against physical threats. The very thin onychodermal band is more easily spotted with its pinkish or brownish visible line that marks the border between the nail bed and hyponychium. The hyponychium is where the nail bed meets the skin on the exterior (where the nail plate separates from the nail bed).

Throwing all these words around might sound confusing, but by visually seeing it on my very well drawn out illustrations, each structure is made clearer, especially location-wise.

Diagrams of the structure of the nail; one shows an above view of the finger with the nail components, and the other is of a side view.

Types of Conditions

Your nails, being formed from previously living keratin cells, are big signifiers for underlying medical conditions. Some of these conditions may be systemic, meaning it affects your entire body or many parts, while others solely affect your nails. Nails being able to predict one's health can help doctors distinguish and treat conditions.

Some common signs of concern include:

-color change

-pits, ridges, or lines

-flaking or peeling

-pain and swelling

Although sometimes visual changes in nail color, shape, or texture aren’t always an issue, they can point to a disease. For example, a subungual hematoma, a common nail injury where direct trauma to the nail causes blood to pool and dry under the nail plate, causes visual changes but isn’t a signifier of a condition or disease.

Looking more specifically, here are some common nail conditions:

Clubbing: Curved and rounded appearance of nails downwards. It can begin gradually, and as it continues to curve downwards, the finger or toe begins to swell. This can be an indicator of low oxygen levels and disease in the lungs, heart, liver, stomach, or intestine.
Yellow nail syndrome: Yellow nails can occur from wearing red nail polish with no base coat, smoking, or a nail infection. But if paired with thickening and cessation of growth, it can signify an internal problem such as lung disease and rheumatoid arthritis (a chronic autoimmune disease where the immune system attacks the synovium, or joint lining).
Koilonychia: Concavity or bending upwards of nails to where they appear like spoons. This can be seen in people who have a chronic iron deficiency, usually due to a lack of nutrition, stomach or intestine health issues, celiac disease (small intestines hypersensitive to gluten), or high altitudes.
Brittle nails: Characterized by dry, fragile, and prone to breaking nails. Can point to nutritional deficiencies, medication, skin diseases like eczema (itchy, inflamed, dry skin), or underlying medical conditions.
Subungual melanoma (nail cancer): Appears as a black, brown, or dark red line or band. Affects a single nail (fingernail or toenail) at a time. The line goes deeper below the nail and can cause other symptoms like bleeding, cracking, and/or brittleness. As melanoma is the most deadly type of skin cancer, this condition can be fatal, and treatment is required promptly.
Paronychia: nail infection caused by bacteria entering exposed skin around the nail plate. This leads to redness and swelling around the nail, and your nail can also turn a greenish-black color.
Nail psoriasis & Pitting: this type of psoriasis most commonly affects your fingernails and leads to pitting, or many icepick-looking dents. Most times, these small depressions on the surface of the nail plate are seen as a symptom of diseases such as alopecia areata, atopic dermatitis, and psoriasis.
Nail lines: discolored streaks that can run vertically or, at times, horizontally on your fingernails or toenails. Some causes include minor injuries, vitamin or mineral deficiency, medication reaction, or medical conditions.
Pincer: very rounded nail plate where the sides grow almost inward. The tips of the nails look narrowed and severely arched, leading to a painful compression on the nail bed. Aging and medication are common causes.
Onychocryptosis & Retronychia: Aka ingrown toenails. Onychocryptosis is when the nail plate grows into the lateral fold (side skin). Retronychia is when the nail grows into the proximal fold (skin at the base), which can cause a “nail-under-nail” appearance.
Onycholysis: aka nail separation. It occurs when your nail plate lifts from the nail bed. The nail lifting up shows a white discoloration. This is usually due to medications, fungal infections, a disease such as psoriasis, or repeated trauma from manicures/pedicures.
Onychonycosis: toenail fungus that can affect any of your nails, but especially your big toe. Walking barefoot in public showers or pools can raise the risk of developing this.
Onychogryphosis: aka Ram’s horn nails, are nails that appear thickened and overgrown. The nails also turn an opaque yellow-brown color and curve into a claw-like shape. Causes include genetics, diseases, or circulation issues.
Onychotillomania: it’s an irresistible urge to pick, tear, or pull at one's own fingernails or toenails. It’s considered a psychocutaneous disorder (conditions involving interactions between the mind and the skin) and is often linked to underlying mental conditions. The nails look to have grooves and ridges in the middle.

Treatments

There are several treatments that can heal or improve these conditions. Of course, each condition has its specific treatment and suggested medication, but as a broad view, here are some treatment types:

-Topical medications (those that are applied as creams or droplets) that target infection and the reduction of pain

-Oral medications that target specific conditions

-Supplements like vitamins and minerals that help strengthen our nails

-Nail surgery or avulsion (removal), which involves applying a chemical to the nails

Some recommended things you could do to prevent the development of any of the previously mentioned conditions include:

Wearing gloves when doing dishes or specific chores
Cutting your nails straight across so as not to develop an ingrown nail
Not biting or picking your nails
Do not overwhelm your nails with constant nail polish, and avoid or limit gel manicures
Wearing shoes that don’t fit and squish your toes
Avoid walking barefooted n places that coil contain a lot of bacteria or fungi, like public showers or next to swimming pools
Curate a “nail care routine” if you have specific concerns, such as brittle nails, to effectively hydrate and moisturize them
And most important of all, if symptoms seem to not improve or are causing immense dysfunction, then it’s better to visit your dermatologist.

Final Thoughts

Despite their small nature, our nails play a big role in our lives. From serving as daily tools to being a form of expression through the artistry of pedicures, our nails make their presence very impactful. But above all, nails can be our guides in signifying potential problems from developing too intensely internally. They are a reflection of our overall health; thus, proper consideration and care are crucial.