7 Foods to Eat for Strong and Healthy Nails

• Deterioration of the nails is a visible sign of mechanical stress or a lack of certain nutrients.
• In particular, an adequate intake of protein, vitamins, and minerals is crucial for healthy nails.
• Before turning to dietary supplements, it is advisable to focus on maintaining a varied and balanced diet.

Fragile and brittle nails affect up to 20% of the population at some point in their lives, most commonly women over the age of 50. The most frequent causes include mechanical stress, exposure to chemicals (e.g., cleaning without gloves), and a poor diet lacking important nutrients. In this article, we'll explore which nutrients have the greatest impact on nail health and what foods you can find them in.

Nutrients for healthy nails: proteins, minerals and vitamins

Nails are mostly made up of a protein known as keratin. There are several types of keratin, and nails contain both ‘hard’ hair keratin (80–90%) and ‘soft’ epithelial keratin (10–20%). Keratin is rich in sulphur amino acids, containing mainly L‑cysteine. These sulphur amino acids form disulfide bridges, which give nails their strength and hardness. It’s estimated that up to 10% of a nail’s weight is sulphur.

Because of this, it's important to consume high‑quality protein that provides the amino acids needed for keratin production. Among minerals, elements such as magnesium, iron, zinc, calcium, copper and sodium play an important role, while selenium also contributes to nail health. Of the vitamins, biotin (vitamin B7) appears to be the most essential, though some studies also highlight the importance of vitamin B12 and vitamin C.

When deficiencies in certain micronutrients are identified, dietary supplements can help replenish them. However, a varied and balanced diet should always be the foundation.

7 foods that support nail health

1. Eggs

Eggs are a rich source of high‑quality protein, which plays a key role in maintaining healthy nails. They contain a high proportion of sulphur‑containing amino acids, particularly L‑cysteine and L‑methionine (3.5–4.5% of the amino acid spectrum). These are critical components of keratin, the protein that gives nails their strength. Among common protein sources, eggs are among the richest in natural sulphur content.

In addition to protein, eggs are high in selenium (31 μg per 100g) and biotin (20 μg per 100g), both of which are essential for nail health.

2. Pumpkin seeds

Pumpkin seeds are one of the richest natural sources of minerals that are often deficient in the human diet. Their magnesium, iron and zinc content can be seen in the table below:

Pumpkin seeds also contain a relatively high amount of protein (37g per 100g), which also has a relatively high quality index (PDCAAS = 0.9).

3. Almonds

Almonds are another abundant source of minerals:

In addition, almonds are an excellent source of vitamin E  (211% RDI per 100g), which is an important antioxidant for the human body.

4. Dairy products

The proteins found in milk and dairy products — whey and casein — rank among the highest in quality, according to measures like PDCAAS or DIAAS. Ensuring adequate protein intake is essential for the body’s natural production of keratin, which forms the structure and strength of nails.

The amounts of protein in selected dairy products are as follows:

5. Beef liver

Beef liver is one of the richest dietary sources of biotin, providing 36 micrograms per 100g (72% of the recommended daily intake).

Biotin has two important roles in relation to healthy nails:

• It plays a direct role in keratin production as part of specific enzymes.
• It enhances the structure and resistance of nails to physical stress.

Although biotin is often included in “Hair–Nails–Skin” supplements, excessive intake is a matter of debate. Supplementing is typically unnecessary if your diet already provides enough biotin.

6. Black beans

Black beans are a nutritious and versatile food. They offer a good amount of protein, along withzinc, magnesium, biotin, and iron — all important for nail health.

The iron content of black beans is above average compared to other foods (36% RDI per 100g), but the lower absorption of iron compared to animal sources must be taken into account. To enhance iron absorption, pair black beans with vitamin C‑rich foods like citrus fruits, peppers, or potatoes. Low iron levels — especially serum ferritin below 10 ng/ml — are commonly linked to poor nail quality.

7. Bioactive collagen peptides

Bioactive collagen peptides produced by the hydrolysis of collagen proteins are now an increasingly popular dietary supplement. For example, in a 2017 study of 25 women aged 26 to 50 years, a 42% reduction in nail breakage and damage was observed when bioactive collagen peptides Verisol® (2.5g daily for 24 weeks) were administered.

Bioactive collagen peptides are now commonly sold as dietary supplements. However, before taking them, it is advisable to ensure a varied and balanced diet with sufficient micro- and macronutrients.

• Learn more: 8 Foods to Eat for Healthy Hair

Bottom line

Healthy, strong nails are rooted in a balanced, nutrient‑rich diet. Nail deterioration is often an early sign of nutritional deficiency.  Protein is essential, as the body uses it to produce keratin, the main structural component of nails. Other key minerals include magnesium, zinc, iron, selenium, calcium, sodium, and copper. For nail health, include important vitamins such as biotin (B7), as well as vitamin C and vitamin B12.