What causes the phenomenon of koilonychia (spoon-shaped nails)?
Mar 19, 2025
Source: Cainiu Health
Dr. Liu Wenmin
Introduction
Koilonychia refers to spoon-shaped nails. In general, koilonychia may be caused by genetic factors, bad habits, malnutrition, psoriasis, hyperthyroidism, and other reasons. Symptomatic treatment is required through general therapy, medication, and other methods. In daily diet, it is recommended to maintain a balanced diet, eat more fresh vegetables and fruits, and avoid picky eating, which helps maintain overall health.
The koilonychia phenomenon refers to spoon-shaped nails. Generally, spoon-shaped nails may be caused by genetic factors, bad habits, malnutrition, psoriasis, hyperthyroidism, and other factors. Symptomatic treatment through general therapy, medication, and other methods may be required. If discomfort occurs, it is recommended to seek timely medical attention and undergo appropriate treatment under the guidance of a physician. A detailed analysis is as follows:
1. Genetic Factors
Genetic factors may lead to abnormal structure or composition of the nail matrix, affecting the normal growth and shape of the nails. Usually, no special treatment is required; cosmetic repair measures may be considered, such as nail overlays or nail fillers.
2. Bad Habits
Habitual nail biting may cause damage to the surrounding skin, infection, or even paronychia, thereby affecting nail growth and presenting with spoon-shaped nail symptoms, possibly accompanied by redness, swelling, pain, or itching of the surrounding skin. It is recommended to correct bad habits and avoid nail biting or picking.
3. Malnutrition
Long-term unbalanced diet lacking in vitamins, trace elements, and other nutrients may lead to insufficient nutrient supply required for nail growth, thus causing spoon-shaped nails. This may be accompanied by systemic symptoms of malnutrition such as dry skin, hair loss, and fatigue. It is recommended to maintain a balanced diet and consume more foods rich in protein, vitamins, and minerals, such as lean meat, eggs, and fresh fruits and vegetables.
4. Psoriasis
Psoriasis is an immune-mediated inflammatory disease characterized by excessive proliferation of keratinocytes. It may cause thinning and pitting of the nails, resulting in spoon-shaped nails, possibly accompanied by skin erythema, scaling, and itching. It is recommended to follow medical advice to use medications such as calcipotriol ointment, tacalcitol ointment, or tazarotene gel to alleviate symptoms.
5. Hyperthyroidism
Autoimmune disorders, genetic factors, environmental factors, and others may lead to hyperthyroidism. Thyroid hormones regulate nail growth; excessive thyroid hormone may accelerate nail growth, but also reduce nail hardness and resilience, making deformation and spoon-shaped nails more likely. Patients may also experience symptoms such as palpitations, hand tremors, and excessive sweating. It is recommended to follow a physician's guidance and take medications such as methimazole tablets, propylthiouracil tablets, or carbimazole tablets for treatment.
In daily diet, it is recommended to maintain a balanced diet, eat more fresh vegetables and fruits, and avoid picky eating habits, which helps maintain overall health.
