Stains on nails

White Spots on toenails and fingernails (leukonychia) are relatively common.

Leukonychia is the medical term that refers to white spots.


How do spots form on the nails? Pathophysiology

The spots on the nails are color changes:

  • in the nail plate, the rigid external structure of the nail, which consists of keratin,
  • in the nail bed, this is the skin on which the nail rests.

A healthy fingernail and toenail is semi-transparent. The pink color is due to the nail bed.
The spots on the nails appear when:

  • pigments settle in the nail plate, for example, nicotine or nail polish;
  • the nail plate suffers injuries, for example during trauma;
  • the nail bed changes color, e.g. due to the formation of a bruise or hematoma.

The spots on the nails can have different colors.
Most often they are harmless, but some spots can also be an indication of:

  • diseases of the skin and nails, such as mycosis (fungal infection);
  • breathing disorders that provoke oxygen starvation in the blood;
  • systemic diseases, such as liver problems.

Types of white spots on the nails

Depending on the severity of color loss, leukonychia can be divided into:

  • Leukonychia punctata: This is the most common form that causes small white spots on the nails. Scratching and biting the nails are the main causes in young children and those who have the habit of chewing on nails.
  • Leukonychia striata: This is a whitening or discoloration in different white “transverse stripes” parallel to the base of the nail.
  • Leukonychia partiale: Here the nail tends to become partially pale or white.
  • Leukonychia totale: In this type, the entire nail turns white.

Causes of stains on the nails

Bright spots on the nails

Vitamin and mineral deficiencies
The lack of vitamins and mineral salts can cause white spots on the toenails and fingernails.
If the diet is low in zinc, this can lead to an increase in bright spots.
As a rule, the nails are also:

  • brittle
  • thin.

Among the symptoms of vitamin deficiency also include:

  • Hair loss
  • Weakness of the immune system.

Infection caused by fungi and mold: nail fungus (onychomycosis)
Often an infection that forms under the nail causes white spots.
When a fungus penetrates the nail and begins to grow, a whitish or yellowish zone may appear on the nail.
There are three types of fungal infections that affect the fingernails and toenails:

As a rule, you can see them more at the tip of the nail.
Nail fungus is commonly found on toenails, especially on the big toe.
The big toe is more exposed to trauma (e.g. wrong footwear).
People with sweaty feet are predisposed to this condition.

If the infection is not treated, the nail may peel off, but also begin to stand out or split.

Often the white spots are caused by trauma to the nails.
Sometimes a lesion can be caused by cutting the nails.
If white spots appear on the nails, it should be checked whether they have arisen due to injury. The white spots do not manifest themselves immediately after a lesion, but it can take a few days or weeks before you notice them.
The reason for this is that the trauma hits the nail matrix (needle root), where the nail plate originated.

Allergy and contact dermatitis
An allergy to certain products can lead to white nail spots.
Dermatitis can affect the following areas:

  • nail base: in some cases it reaches the nail matrix and the forming nail plate may be deformed and thickened;
  • Nail end: a hard white layer of skin may form under the nail (hyperkeratosis).

An allergic reaction can be triggered by:

  • household cleaners,
  • Nail polish
  • Nail polish remover.

Dark spots that spread on the nail

If the skin color is dark, you can probably also discover dark streaks on the nails.
This is true for about 20/<> of the over-<>s in the black population and is completely normal in most cases.
Nevertheless, dark streaks can be caused by skin cancer that affects the nail bed and is called subungual melanoma.
Usually, a subungual melanoma concerns:

  • only one nail;
  • Over time, the appearance of the strip changes (it may become darker or wider) and the pigmentation can spread to the surrounding area (nail fold).

Small red or brown stripes under the nails

If small red or brown streaks appear under the nails, these may be bleeding caused by injuries to the smallest blood vessels.
Only a few stripes under the nails are harmless, as they are more likely caused by injuries to the nail.
If these changes occur in multiple nails, it can be a sign of health problems, such as:

Yellow spots on nails

The most common cause of yellow nails are:

  • Fungal infection
  • Psoriasis.

The big toenail is most often affected by a fungal infection.

According to a study published on the website of the American Family Physician (Scher RK. Acquired immunodeficiency syndrome and yellow nails. J Am Acad Dermatol. 1988;18(4 pt 1):758–9), yellow nails can be caused by any of the following:

  1. Frequent use of colored nail polish: the color pigments can stain the nail plate. To avoid yellowing of the nails, a layer of colorless nail polish should first be applied under the colored one.
  2. lymphedema, a disease of the lymphatic system that causes congestion of lymph (a body fluid) in the limbs and swelling of the skin;
  3. respiratory problems such as: bronchiectasis (a chronic widening of the bronchi), sinusitis (inflammation of the inner walls of the sinuses), tuberculosis (a bacterial infection that affects the lungs);
  4. inflammation of the thyroid gland (thyroiditis);
  5. jaundice (yellowing of the skin) due to liver disease such as cirrhosis;
  6. some medicines, such as those containing thiols;
  7. Immunodeficiency;
  8. rheumatoid arthritis.

A red or yellow spot under the nail

A red or yellow spot under the nail

If there is a salmon-colored (orange) spot under the nail on the nail bed, it may be a skin condition called psoriasis.

In psoriasis, other changes to the nail are usually noticeable, such as:

  • dimpled nails (pitting): small holes form on the surface of the fingernails;
  • Nail detachment (onycholysis): the outer edge of the nail detaches from the nail bed. The detached nail is white and the part still adhering to the finger may be reddened.

Half white and half brown nails

Nails that are half white and half brown-red (brown at the edge of the nail) are called half-and-half nails.
They are an indication of renal insufficiency, a disorder of correct renal activity.
The connection is not fully understood, but the theory is that renal insufficiency can cause chemical changes in the blood that stimulate the formation of melanin (a skin pigment) in the nail bed.
It is possible that renal insufficiency causes an increase in the small blood vessels in the nail bed. It is estimated that up to 50% of patients with renal insufficiency have half and half nails.
Half-and-half nails are also observed in:

  • some people with AIDS,
  • in children after chemotherapy.

Different colored spots on the nails

  • Green-black nails can be observed after rapid growth of so-called Pseudomonas bacteria, especially under nails that peel off. These can be treated by applying antibiotics to the skin and under the detached nail.
  • Blue-gray nails can be caused by medications such as antimalarials or antibiotics such as minocycline.
    As a rule, a few months after the suspension of pharmacological therapy, the nails return to their normal color.
  • Black-brown spots can be caused by:
    • thyroid diseases,
    • pregnancy,
    • Malnutrition (lack of vitamin B12).
  • Blue or purple nails indicate circulatory or lung problems that cause lack of oxygen in the blood, such as asthma or emphysema.

Diseases that provoke nail problems

Beau Lines

The white horizontal furrows on the nails are called Beau lines.
According to an article published in Indian Dermatol Online J, apart from trauma, they can be caused by:

If the Beau lines appear on all nails (on toes and fingers), the following causes are possible:

  • Parotitis (inflammation of the parotid gland)
  • Anaemia
  • Pneumonia
  • Thrombosis of the coronary arteries
  • Kawasaki disease
  • Syphilis
  • Hypoparathyroidism (underactive parathyroid glands)

Onycholysis, brittle and cracked nails
Oncholysis (the detachment of the nail plate from the nail bed) and nail dystrophy (change in shape, color or thickness) can be caused by:

  • Psoriasis
  • Thyroid disorders such as hypothyroidism or hyperthyroidism ;
  • Lack of iron or vitamin A.

Vertical stripe

Parallel longitudinal stripes can be caused by:

What to do? Therapy for stains on the nails

Treatment is not necessary if the stains:

  • are small,
  • occur in isolation,
  • lie in the middle of the nail.

These spots are located in the hard nail plate and shift further and further upwards as the nail grows, so they pass by themselves.
The type of spots is not a sign of health problems, usually they are provoked by small traumas on the nail.

If the white spots are very extensive or streaks appear all over the nail, a doctor should be consulted because they can be signs of disease.

Various over-the-counter therapies and natural remedies (home remedies) are available to treat this disorder.

Antifungal agents and antibiotics
There are local or oral medications that are often used for nail spots caused by fungal infections.
In case of infections, the doctor prescribes:


Hydration of fingers and toes: Fingers and toes, including nails, must be regularly hydrated.
Vitamin E-containing oil nourishes the nails and surrounding skin and keeps them moist. In this way, dry skin can be prevented, which can lead to cracks and infections.

Manicure: Proceed carefully, because a too bold manicure can have consequences:

  • trauma at the root of the nail,
  • white spots.

Diet and nutrition: The diet should be rich in fruits and raw vegetables.
These foods contain nutrients that are important for nail health:

  • Calcium
  • Iron
  • Roughage
  • Vitamins
  • Minerals.

Avoidance of irritants: It is important not to expose the nails to chemical products.

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