Most of us don’t pay much attention to the nails on our fingers and toes. However, checking in regularly on the appearance of our nails can be helpful in monitoring our health status. Abnormalities in the appearance of your nails may indicate a health problem that could be serious.

Changes in the appearance of your nails, such as pitting or ridges, may indicate some sort of change in your health. Another condition that can affect the nails is hapalonychia, sometimes called “eggshell nails.” Hapalonychia causes your nails to be soft and thin. Nails affected by this condition tend to bend or break more easily than healthy nails, and often split or flake at the end. They may also take on a bluish tint.

There are several reasons a person may develop hapalonychia. These environmental factors, genetic conditions, nutritional deficiencies, diseases, medicines, and trauma. While most causes of hapalonychia may not cause severe or long-term harm to your health, there are also a few serious conditions that can cause hapalonychia.

If you notice your nails seem more soft or brittle than usual, it can be helpful to speak with a doctor. They may help you better understand and treat the underlying cause.

Here are some common causes of hapalonychia:

Environmental factors

Most commonly, hapalonychia is caused by environmental factors. Repeated wetting and drying of the fingernails can cause them to lose their moisture and weaken. This is a common problem for people who live in places that get cold and dry in the winter. Exposure to chemicals may also weaken your nails and cause hapalonychia. Some common chemicals associated with weaker nails include detergents, cleaning fluids, and nail polish removers (particularly those with acetone).

Iron deficiency

A lack of iron in the body, also called iron deficiency anemia, can cause hapalonychia. There are several causes for iron deficiency in the body. They range from blood loss (including that lost during menstruation), to a lack of iron in your diet.

Iron deficiency anemia may also be caused by a condition that prevents your body from absorbing iron from food, such as celiac disease. Pregnancy may also cause iron deficiency anemia. Other symptoms of iron deficiency anemia include:

  • fatigue
  • pale skin
  • weakness
  • chest pain
  • headaches
  • lack of appetite


One of the most common causes of hapalonychia is malnutrition, which means your body is either getting too little (or in some cases, too much) of a certain nutrient or nutrients. Hapalonychia is frequently linked to deficiencies of B vitamins, calcium, iron or fatty acids (like omega-3s). Those experiencing malnutrition may also feel tired, have dry skin or hair, and experience weight loss.

Raynaud’s phenomenon

Raynaud’s phenomenon is a condition that causes the body’s blood vessels in the hands and feet to react more strongly than usual to cold temperatures and stress. People with this condition experience “attacks” where fingers and/or toes become extremely cold, and may even change color. Upon warming or stress relief, you may feel numbness, stinging, or a prickly feeling.

Various factors may contribute to a person’s development of Raynaud’s phenomenon, such as arterial diseases, smoking tobacco, or injuries, though the exact cause is not well understood. People with Raynaud’s phenomenon often experience hapalonychia due to constricted blood flow to the fingers.

Side effect of medications

Some medications and medical treatments, such as chemotherapy and immunotherapies, can cause your nails to develop hapalonychia. The drugs used to treat cancer are particularly strong and may stop the growth of your nails temporarily. This can cause horizontal lines, called Beau’s lines, to develop on your nails.

Thyroid diseases

The thyroid is a gland in our necks that sends out chemicals called hormones that regulate our metabolism and other body functions. Hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid) place stress on the body that can contribute to a person’s development of hapalonychia.

There are many possible causes of issues affecting the thyroid, including inherited conditions, cancers, and certain medications. You may be experiencing thyroid problems if you’ve noticed a change in your:

  • weight
  • nails
  • skin
  • hair
  • energy levels
  • appetite
  • blood pressure
  • ability to tolerate the cold

Treatment for hapalonychia depends on its cause.

Treatment for environmental factors

Environmental factors tend to be easiest to cope with. Protect your hands and fingers from extreme cold and heat. Avoid direct contact with chemicals, and cover your hands with gloves when cleaning or doing other activities that involve handling chemicals. Trading harsh cleaning products for those made of natural and less toxic chemicals may also be easier on your nails. You could swap acetone nail-polish remover for acetone-free remover, for example.

Treating nutrition-related causes

If your hapalonychia is caused by malnutrition or iron deficiency anemia, you’ll need to correct your nutrient intake. A doctor may first run tests to determine what might be causing your deficiency. Nutrient deficiencies may be corrected by a change in diet or addition of supplements to the diet. In some cases, malnutrition or iron deficiency could be caused by an underlying health issue such as parasites or a food intolerance.

Medication interactions and more serious underlying causes

If you’re taking a medication that may be causing hapalonychia, speak with your doctor about your options. Similarly, if you have a thyroid issue or Reynaud’s disease, taking care of the underlying condition should clear up your hapalonychia.

General nail and skincare

Regularly applying lotion to clean hands can help keep your nails healthy and moisturized. Taking good care of your nails can also improve their health and appearance: Filing, shaping, and trimming your nails on a daily basis can possibly help prevent hapalonychia.

Some people add a protective layer of nail hardener to their nails to add protection. Some also find their nail health is boosted by taking a daily dose of biotin, a vitamin associated with nail growth. Do not take biotin if you are pregnant.

Try to avoid biting and picking your fingernails. Also avoid using harsh nail products and pulling off hangnails.

If you’ve noticed hapalonychia or other nail changes that do not improve over a few weeks, make an appointment with a doctor. They will be able to help find out what’s causing your hapalonychia, so that you can develop a treatment plan that will help this pesky nail issue go away.

Some causes of hapalonychia can be corrected at home, such as trading out acetone nail-polish remover for nail-polish remover that’s acetone-free. However, to treat hapalonychia caused by medical issues, you may require treatment from your doctor.