Brittle Nails: 9 Common Causes (& What To Do)

Updated in April 2024

Brittle nails can occur as a result of direct contact with chemical products, such as detergents or acetone, which can dry-out the nails and make them weak. Brittle nails can also occur due to frequent nail biting, which causes microtrauma to the nail.

However, weak, dry or brittle nails can also be a sign of a health condition, such as vitamin and mineral deficiencies, anemia, thyroid problems or changes in circulation. These health conditions are generally accompanied by other symptoms, such as muscular weakness, fatigue excessively dry skin or swollen fingers.

Therefore, it is important to consult a general practitioner or dermatologist if you notice brittle nails with other symptoms. The doctor will likely order testing to determine the underlying cause and initiate treatment as appropriate.

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Why are my nails so brittle?

The most common causes of brittle nails include:

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. It can also increase the risk for infection around the nail.

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. Check-out other tips to stop biting your nails that you can use.

2. Cleaning products

Using cleaning products without gloves can dry out your hand skin and nails, leading to brittle nails. These products contain chemicals that can dry-out the skin and nails, leaving them more prone to breaking.

Acetone used in nail polish or formaldehyde used in other nail products can also lead to the appearance of spots on the nails and can also make nails weaker. 

Also recommended: White Spots on Nails: What Causes Them & How to Treat

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, especially deficiencies in vitamins and minerals like iron, folic acid, vitamin A, vitamin B12 or vitamin C, can also result in weak and brittle nails. These are nutrients needed to produce protein that strengthens the nails.

Also recommended: Vitamin B12 Deficiency: Symptoms, Causes & Treatment

Nutritional deficiencies can develop due to low intake of nutritious foods, such as meat and eggs, for example, or due to restrictive diets or bariatric surgery, which can alter the absorption the way nutrients are absorbed from food.

In addition to weak and brittle nails, nutritional deficiencies can lead to symptoms such as excessive fatigue, dizziness, paleness or changes in vision

What to do: You should see a doctor if you suspect a nutrient deficiency so that testing can be ordered to confirm a diagnosis. If confirmed, the doctor may refer you to a registered dietitian to assess your current diet and provide meal recommendations to correct any deficiencies through diet. 

Also recommended: Vitamin C Foods: 21 Foods, Supplements & How to Consume

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. Read more about the symptoms of anemia and how they can present.

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 experience 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. 

Also recommended: 6 Thyroid Tests That Detect Thyroid Abnormalities

6. Skin infections

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. 

Also recommended: Nail Fungus: Symptoms, Causes & Treatment

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. 

7. Prolonged use of gel nails

Prolonged use of gel nails can make your nails weaker and more brittle, as it can cause dehydration and dryness in your nails.

Removing gel nails incorrectly or at home using a spatula, acetone, nail polish remover, or by filing the nail, can also damage the nails, leaving them thinner, weaker and more brittle.

What to do: You should attend maintenance appointments to keep your gel nails and cuticles in good shape. You should also use moisturizing creams that are appropriate for your hands. Furthermore, gel nails should be removed by a manicurist, and care at home after removal includes keeping nails short and clean. You can moisturize the nails with grape seed oil, or use a strengthening base polish, or light-colored nail polish. Be sure to avoid removing the cuticles, especially during this time.

Also recommended: Yellow Nails: 9 Common Causes & What to Do

8. Circulatory problems

Circulatory problems, such as Raynaud's syndrome, can make the nails weaker, due to a narrowing of the blood vessels. This leads to reduced blood flow, which means that less oxygen reaches the hands and fingers. Other symptoms of this condition include swelling, pain, or increased sensitivity in the hand and fingers.

Raynaud's syndrome can be caused by prolonged cold exposure, or other health problems such as scleroderma, hypothyroidism or polycythemia vera.

What to do: You should consult a general practitioner or angiologist, to confirm a diagnosis and to guide the best treatment approach. Antihypertensive medications are generally prescribed to improve blood circulation and relieve symptoms.

9. Excessively removing cuticles

Cuticles are a layer of thin skin at the base of the nail that provide a protective barrier against trauma, inflammation or infections caused by fungi or bacteria.

By deeply removing the cuticles, or biting or pulling at the cuticles, it can damage the base of the nail, leaving the nails weaker, brittle, wavy or with white spots. It can also increase the risk for infections, such as paronychia or ingrown toenails.

What to do: You should ideally avoid removing the cuticles to ensure the nails remains protected and strong. A great way to keep your nails beautiful, without removing the cuticles, is to use moisturizing hand creams after washing your hands or bathing. You should also drink plenty of water during the day to remain hydrated, and to wear gloves whenever you handle  detergents or other cleaning products.