Vertical lines on the nails are extremely common, especially as we get older. In most cases, they’re harmless and simply reflect normal nail growth. However, when ridges become more noticeable, nails start to break easily, or changes appear in texture or color, nutritional factors may be involved.

Making improvements to your diet can help promote stronger, smoother nails over time.

1. Protein: Essential for Nail Structure

Nails are primarily composed of keratin, a type of protein. When protein intake is too low, nails may become thin, weak, or more prone to ridging and splitting.

Good protein sources include:

• Eggs
• Lean poultry
• Fish
• Greek yogurt
• Beans and lentils
• Tofu

Including protein at each meal supports consistent keratin production and healthier nail growth.

2. Biotin (Vitamin B7): Supports Nail Strength

Biotin is widely known for its role in improving brittle nails. Many people can meet their needs through food alone.

Biotin-rich foods include:

• Fully cooked eggs
• Almonds and walnuts
• Sweet potatoes
• Spinach
• Salmon

Biotin helps reinforce keratin, allowing nails to grow thicker and less fragile, which may make ridges less visible.

3. Iron: Helps Prevent Weak or Grooved Nails

Low iron levels can lead to thin, fragile nails and, in more severe cases, spoon-shaped nails.

Iron-rich foods include:

• Lean red meat
• Chicken thighs
• Lentils
• Chickpeas
• Pumpkin seeds
• Dark leafy greens

To enhance absorption from plant-based sources, pair iron-rich foods with vitamin C options like citrus fruits or bell peppers.

4. Zinc: Supports Growth and Repair

Zinc plays a role in cell regeneration and tissue repair. A deficiency may show up as ridges, white spots, or slowed nail growth.

Foods high in zinc include:

• Oysters
• Beef
• Cashews
• Sunflower seeds
• Whole grains

Because the body doesn’t store much zinc, regular intake is important.

5. Omega-3 Fatty Acids: Improve Moisture and Flexibility

Dry, brittle nails can make ridges appear more pronounced. Omega-3s help maintain moisture in the nail bed and reduce inflammation.

Good sources include:

• Fatty fish such as salmon, sardines, and mackerel
• Chia seeds
• Flaxseeds
• Walnuts

Healthy fats also support circulation, helping nutrients reach the nail matrix.

6. Don’t Forget Hydration

Dehydration can worsen nail dryness and make ridges more noticeable.

Support hydration by:

• Drinking adequate water daily
• Eating water-rich foods like cucumbers, oranges, and watermelon

Well-hydrated nails are more flexible and less likely to crack.

When to Consult a Doctor

While nutrition can help over time, some nail changes require medical attention, including:

• Deep horizontal grooves (Beau’s lines)
• Dark streaks
• Painful nail changes
• Sudden shifts in color or texture

These may indicate underlying health issues rather than dietary causes alone.

The Takeaway

Stronger, healthier nails start from within.

Focus on:

• Adequate protein
• Biotin
• Iron
• Zinc
• Omega-3 fats
• Proper hydration

Be patient—nails grow slowly, so noticeable improvements may take several months. With consistent nutrition and healthy habits, nails can naturally become smoother, stronger, and more resilient over time.