Brittle Nails: 6 Common Causes & What To Do

Updated in June 2022

Brittle nails and broken nails are not a concerning symptom. It can happen with daily use of cleaning products, or from having a bad habit of nail biting.

However, brittle nails can also be a sign of a health problem, especially if accompanied by weakness, headache or dizziness. These can happen with illnesses like anemia, nutritional deficiencies or hormonal changes. 

If you nails are notably fragile and thin, you should see your doctor or dermatologist for assessment to investigate what is causing brittle nails and start adequate treatment. 

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1. Nail biting

Biting your nails constantly can lead to them becoming for fragile, due to the presence of microtraumas that cause them to break easily. 

What to do: In this case, you should stop biting your nails. Ensure they are cut short and filed down to avoid this habit and promote regrowth. You can also apply a bitter-tasting nail polish specifically formulated for nail biters. 

2. Cleaning products

Using cleaning products without gloves can dry out your hand skin and nails, leading to brittle nails. Acetone used in nail polish remover can also lead to the appearance of spots on the nails and can also make nails weaker. 

What to do: Be sure you protect your hands and nails with gloves if using cleaning products frequently. To remove nail polish, you should look for nail polish remover that does not contain acetone. 

3. Low nutrient and vitamin intake 

Nutritional deficiencies can also lead to brittle nails, especially in diets with low iron, vitamin D, zink, selenium and vitamin B. These nurtients are found in meat and eggs, and promote healthy skin, hair and nails. 

What to do: You should see a registered dietitian if you have any nutritional deficiencies so that a customized diet plan can be formulated to address your brittle nails. Learn more about foods that are rich in vitamin D

4. Anemia

Anemia is one of the main causes of brittle nails. It is characterized by a decreased level of circulating hemoglobin, which means that less oxygen is being transported and delivered to tissues. 

Because of decreased oxygen levels in the blood, people may notice symptoms like brittle nails as well as fatigue, weakness, and decreased mood. 

What to do: If anemia has been confirmed through blood work, you and your doctor should discuss what is causing it, as this will help to guide treatment and reduce related symptoms. 

5. Thyroid changes

Thyroid changes can also lead to brittle, breaking nails. With hypothyroidism, for example, people often expereince decreased metabolism and a reduction of nutrients in the body, causing fragile nails. 

With hyperthyoidism, there is an increase in circulating thyroid problems, which can stimulate rapid nail growth and also cause fragile nails. Learn more about symptoms related to thyroid problems

What to do: You should follow treatment as recommended by your doctor or endocrinologist, as restoring normal thyroid levels may be necessary to resolve symptoms of brittle nails. 

6. Skin diseases

Some skin diseases, especially fungal infections, can lead to weak and breaking nails. Infections can alter nail appearance and cause them to peel. In these cases, you should see a dermatologist for assessment. 

What to do: Treatment will depend on the underlying cause, therefore you should follow treatment as prescribed. If a fungal infection is confirmed, treatment should be initiated with topical antifungals applied directly to the affected nail.