Why Your Nails Split Vertically: Causes & Solutions

Vertical nail splitting, characterized by the longitudinal splitting or fraying of the nail plate, is a common condition that affects many people. This type of nail splitting, medically known as onychoschizia, can be unsightly and uncomfortable. It often signals underlying issues, ranging from simple environmental factors to more complex health conditions. Understanding the causes behind vertical nail splits and how to address them can significantly improve your nail health and prevent future occurrences.

The Structure of Nails

Nails are primarily composed of keratin, a type of protein that’s also found in your skin and hair. Healthy nails are smooth, without pits or grooves, and free of discoloration or splitting. The nail itself is made up of several parts, including the nail plate (the visible part of the nail), the nail bed (the skin beneath the nail plate), and the nail matrix (the root of the nail). When any part of this structure is compromised, problems like splitting can occur.

A basic understanding of nail anatomy is essential to grasp why nails split.

  • Keratin: The Building Block Keratin, a tough protein, is the primary component of nails. It gives nails strength and resilience, but splitting occurs when keratin layers separate.
  • Layers of the Nail Nails are composed of several layers stacked on each other. When these layers dry out or get damaged, they can peel apart, leading to splits.
  • The Nail Matrix The matrix, located at the nail’s base, is responsible for nail growth. Damage or health issues affecting the matrix can lead to nail abnormalities, including splitting.

Causes of Vertical Nail Splitting

Numerous factors can lead to vertical nail splitting. Understanding these can be crucial in addressing the issue effectively.

  • Brittle, Dry Nails: Dryness is one of the most common reasons for nail splitting. Nails lacking moisture are more prone to brittleness and splitting. Environmental conditions, such as low humidity, can exacerbate this, as can excessive hand washing or harsh chemicals without protective gloves.
  • Nutritional Deficiencies: Poor nutrition, especially deficiencies in vitamins and minerals essential for nail health, such as biotin, iron, and vitamin C, can lead to weakened nails that split easily. Iron deficiency anemia is notorious for causing brittle nails that may split or crack.
  • Nail Trauma and Bad Habits: Physical injury to the nail or repetitive trauma, such as regular typing or nail biting, can cause vertical splits. Improper nail care, including the inappropriate use of nail tools, can also contribute to this problem.
  • Health Conditions: Several health conditions can affect nail health. Fungal infections can lead to nail splitting, as can skin conditions like psoriasis and eczema. Thyroid disorders, hormonal changes, and even genetics may play a role in weakening nails.
  • Exposure to Harsh Chemicals: Regular use of nail polish, especially those containing acetone and other harsh nail products, can strip nails of their natural oils, leading to splits.

Diseases That Affect Nail Health

Diseases affecting nail health and potentially leading to vertical nail splitting can range from local infections to systemic conditions. Understanding these diseases can help identify the underlying causes of nail problems and seek appropriate treatment. Here are some of the most common diseases associated with nail splitting:

Fungal Infections (Onychomycosis)

Fungal infections are among the leading causes of nail splitting and degradation. Fungi thrive in warm, moist environments, making the nail bed an ideal location for fungal growth. This can make nails thick, discolored, and brittle, eventually causing splits. Treatment typically involves antifungal medications, either topical or oral, depending on the infection’s severity.


Nail psoriasis is a chronic autoimmune condition that affects the skin and can also impact the nails. It can cause various nail problems, including pitting, discoloration, thickening of the nail, and splitting. Treatment for nail psoriasis may involve topical treatments, light therapy, or systemic medications designed to treat psoriasis more broadly.

Eczema (Atopic Dermatitis)

Eczema is a condition that causes the skin to become inflamed, itchy, and cracked. When eczema affects the hands, it can also impact nail health, leading to brittle nails that may split or peel. Managing eczema through moisturizing, avoiding triggers, and using prescribed medications can help improve nail health.

Thyroid Diseases

Both hypothyroidism and hyperthyroidism can profoundly impact nail health. Thyroid diseases can cause nails to become brittle, thin, and prone to splitting. Medication can help mitigate these nail issues.

Iron Deficiency Anemia

Iron is crucial for many bodily functions, including nail growth. Iron deficiency anemia can lead to spoon-shaped nails (koilonychia) and increased brittleness, making nails more susceptible to splitting. Iron supplements and dietary changes can help improve the anemia and the associated nail problems.

Aging and Hormonal Changes

Nails can become dryer and more brittle as people age, partly due to decreased blood flow and hormone changes. This increased brittleness can lead to more frequent nail splitting. While aging is a natural process, maintaining good nail care and hydration can help minimize its impact on nail health.

Lichen Planus

Lichen planus is an inflammatory condition affecting skin and nails, potentially leading to nail damage and splitting. The exact cause of lichen planus is unknown, but treatment options include corticosteroids and other medications that help control inflammation.

Preventive Measures and Solutions

Preventing vertical nail splits involves a combination of good nail care practices and lifestyle adjustments.

  • Proper Nail Care: Keeping your nails trimmed and filed can prevent splits from worsening. It’s also essential to avoid using your nails as tools to pick or pry things open, as this can cause trauma to the nail.
  • Moisturize: Regularly applying moisturizer to your nails and cuticles can help maintain moisture levels and prevent splitting. Wearing gloves while doing dishes or cleaning products can protect your nails from harsh chemicals and excessive water exposure.
  • Nutrition: Eating a balanced diet rich in vitamins and minerals supports overall health, including nail health. Supplements like biotin have been shown to improve nail strength in some people.
  • Hydration: Drinking plenty of water is crucial for maintaining the moisture balance in your nails and preventing them from becoming brittle.
  • Minimize Exposure to Harsh Chemicals: Use acetone-free nail polish removers and limit the use of nail polish and other harsh nail care products.
  • Professional Treatment: For those with persistent nail splitting, especially if caused by underlying health conditions, seeking advice from a dermatologist or healthcare provider is essential. They can offer treatments tailored to your specific condition, whether it’s a fungal infection, a skin condition, or a nutritional deficiency.

Treatment Options

Treatment options for vertical nail splitting vary depending on the underlying cause. A comprehensive approach, combining proper nail care with specific treatments targeting the root cause, can help manage and even resolve nail-splitting issues. Here are some general and specific treatment options for dealing with vertical nail splitting:

General Nail Care

  • Moisturizing: Regular application of moisturizers or nail oils can help maintain nail hydration, making them less prone to splitting.
  • Protective Gloves: Wearing gloves during household chores that involve water or chemicals can protect the nails from damage.
  • Proper Trimming: Keeping nails trimmed and filed can prevent splits from worsening. Avoid overly aggressive trimming or filing, as this can cause further damage.
  • Avoid Harsh Chemicals: Limit exposure to harsh nail products, including acetone-based polish removers and certain nail polishes that can weaken nails.

Nutritional Supplements

  • Biotin is a vitamin known for promoting hair and nail health. Supplements can strengthen brittle nails and reduce splitting.
  • Iron Supplements: Iron supplements can improve overall health and nail strength for individuals with iron deficiency anemia.
  • Vitamins and Minerals: A balanced intake of essential vitamins and minerals, through diet or supplements, supports nail health. Vitamins A, C, D, and E and zinc and calcium are particularly important.

Medical Treatments

  • Antifungal Medications: For nail splitting caused by fungal infections, antifungal creams, gels, or oral medications may be prescribed.
  • Topical Steroids: In cases where skin conditions like psoriasis or eczema contribute to nail issues, topical steroids can reduce inflammation and improve nail appearance.
  • Phototherapy: A treatment option for nail psoriasis where UV light reduces skin and nail psoriasis symptoms.

Lifestyle Adjustments

  • Hydration: Drinking plenty of water is crucial for maintaining nail moisture and preventing splitting.
  • Dietary Changes: Incorporating foods rich in proteins, omega-3 fatty acids, and antioxidants can support nail health and reduce brittleness.

Advanced Treatments

  • Laser Therapy: Some fungal nail infections resistant to traditional treatments may benefit from laser therapy, which targets the fungus directly without harming the surrounding nail or skin.
  • Nail Removal: In severe cases, particularly when pain is present, or the nail structure is severely compromised, removing the damaged nail might be considered to allow a healthy nail to grow in its place.

Professional Care

  • Consult a Dermatologist or Podiatrist: Persistent nail splitting, especially if associated with signs of infection or other health conditions, requires consulting a healthcare professional. They can diagnose, rule out serious conditions, and tailor treatments to the specific cause.
  • Regular Check-ups: Ongoing monitoring by a professional can ensure that the chosen treatment is effective and adjusted as necessary.

Experimental and Emerging Therapies

In some cases, newer treatments might be explored, like biological therapies for psoriasis or innovative nail repair technologies. These options are typically considered when conventional therapies have failed and are under a healthcare professional’s guidance.


Vertical nail splitting can be frustrating and sometimes painful. However, by understanding the causes and implementing preventive measures, you can significantly reduce the risk of splits. Remember, while home remedies and preventive strategies can be effective for minor issues, a healthcare professional should evaluate persistent or severe nail problems to rule out underlying health conditions. Proper nail care, a balanced diet, and protecting your nails from injury and exposure to harsh chemicals are key steps in maintaining healthy, strong nails free from splits.


  • Michael Reed

    Michael Reed is a medical writer at Sumlab, focusing on dermatological studies and treatments. His articles help demystify complex clinical results for a broad audience.