Lines or Ridges on Nails: Why Do They Appear?

Nail lines develop due to a variety of factors, from skin disorders to nutrient deficiencies. We show you everything there is to know about this phenomenon.
Lines or Ridges on Nails: Why Do They Appear?

Written by Daniela Andarcia

Last update: 24 April, 2023

Nail care isn’t only related to aesthetics; it’s also important for health, as different anomalies that develop on them can reveal different conditions. One of the most common and noticeable irregularities are the lines or ridges on nails.

Despite being harmless, these ridges in nails function as signs of systemic diseases or nutritional deficits, among others. According to a study published in the Indian Dermatology Online Journal, those on the hands provide more accurate information than those on the feet. Find out the cause for lines and ridges on nails and what to do to eliminate them.

What causes the appearance of ridges on nails?

Lines or ridges on nails appear for various reasons – from skin disorders such as atopic dermatitis or eczema, to protein, calcium, zinc and vitamin A deficiencies. The orientation and size of the lines are crucial to determine what is happening.

Anemia in the blood.
One of the signs of anemia can be the lines or ridges on nails.

Vertical lines

Vertical lines are grooves or ridges that extend from the cuticle to the tip of the nail. In general, older adults tend to develop slight vertical ridges as a result of a decrease in cell renewal. This happens when new cells wait below the skin’s surface to replace the dead cells on the outside.

If other abnormalities are also experienced, such as changes in color and texture, a disease can be suspected. For example, in trachyonychia, a condition that may be an isolated phenomenon or associated with other skin disorders, the nail grooves change color and their surface takes on a rough, brittle appearance.

Similarly, people with iron deficiency anemia may also develop vertical lines. Similarly, changes in shape give it a concave or spoon-like appearance.

Horizontal lines

For its part, horizontal furrows, also known as Beau’s lines, are considered a symptom of more serious diseases. These indentations on the nail surfaces can prevent their growth until the condition causing them is detected and treated.

Beau’s lines are an indication of acute kidney disease and, when they develop on all nails both on the hands and feet, then this can suggest the presence of mumps, thyroid disease, diabetes, or syphilis. According to a study published in Acta Haematologica, they also appear in patients receiving chemotherapy treatment.

A blow or trauma is another reason why red or brown spots develop under the nails. One must be very careful not to confuse these color changes with symptoms of diseases such as endocarditis or melanoma. In those cases, you should be on the lookout for a dark brown, black, or red color.

How to determine what’s causing the lines on the nails?

Since the nails can provide valuable information about the state of health, the doctor must be aware of all sudden changes. If you hurt a nail, you should wait a few weeks to see the healing process before going to the doctor. However, if there’s a bad cut with bleeding or if the nail gets crushed or even falls off, then you should go as soon as possible.

In a routine consultation, the doctor examines the nails and, according to what they observe, they can request different tests. Usually, a blood and urine test is sufficient if kidney disease, diabetes, or nutritional deficiencies are suspected.

On the other hand, if the lines on the nails are believed to be related to a skin disease, the dermatologist will initiate treatment. When the cause of the appearance of these grooves isn’t clear, samples are taken to be analyzed in the laboratory.

Ridges in nails.
A biopsy sample may be taken from the nail if there is any question as to the underlying cause.

How to treat or eliminate the lines on the nails?

As we have seen, the appearance of ridges on nails is usually a symptom of other conditions, so it’s necessary to treat them in order to eliminate them. For example, if it has been determined that the grooves are the product of iron deficiency anemia, a medication based on supplements of this mineral will contribute to their disappearance.

Similarly, if the cause is a skin disease such as atopic dermatitis, treatment should include moisturizing hand creams that reduce symptoms. For your part, you can also choose to polish your nails to give them more shine and smooth the irregular surface caused by grooves.

A dermatologist can be consulted on the best way to manage these ridges. It’s essential that you don’t push down on them too hare, in order to prevent more serious problems.

What to remember about the ridges on nails?

The ridges on nails can appear due to different factors. Vertical ridges often develop in the elderly and nutritionally deficient, while horizontal ridges, or Beau’s lines, are symptoms of acute kidney disease, mumps, thyroid disease, diabetes, and syphilis.

It’s important not to underestimate their presence or let time pass. Perhaps a simple medical solution will solve the problem without leading to major complications.



  • Singal, A., & Arora, R. (2015). Nail as a window of systemic diseases. Indian dermatology online journal, 6(2), 67–74. https://doi.org/10.4103/2229-5178.153002
  • Jacobsen, A. A., & Tosti, A. (2016). Trachyonychia and Twenty-Nail Dystrophy: A Comprehensive Review and Discussion of Diagnostic Accuracy. Skin appendage disorders, 2(1-2), 7–13. https://doi.org/10.1159/000445544
  • Rathod DG, Sonthalia S. Spoon Nails. [Updated 2020 Aug 12]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK559311/
  • Ben-Dayan, D., Mittelman, M., Floru, S., & Djaldetti, M. (1994). Transverse nail ridgings (Beau’s lines) induced by chemotherapy. Acta haematologica, 91(2), 89–90. https://doi.org/10.1159/000204261
  • Tikoo, M., Bardia, A., Gupta, A., & Pandey, A. (2015). Dermatological Manifestations of Infective Endocarditis. Journal of general internal medicine, 30(8), 1229–1230. https://doi.org/10.1007/s11606-015-3256-z

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