The Keratin Foundation: How Nails Are Built
Your nails are primarily made of keratin, a fibrous structural protein. The strength and growth rate of your nails depend on a steady supply of nutrients. A lack of these nutrients can result in brittle, weak, or breaking nails, medically known as onychoschizia.
The Primary Nutritional Culprits Behind Brittle Nails
Nutritional imbalances are a common reason for nail brittleness. Addressing these deficiencies can help.
Iron Deficiency
Iron deficiency, which can lead to anemia, is a frequent cause of brittle nails. Iron is essential for transporting oxygen to cells, including those involved in nail growth. Low iron can cause pale nail beds and, in severe cases, 'spoon nails' (koilonychia). Other symptoms may include fatigue and shortness of breath.
Biotin (Vitamin B7)
Biotin helps produce keratin. While severe deficiency is uncommon, some studies suggest biotin supplements can improve nail thickness and hardness in those with brittle nails. Foods like eggs, nuts, and seeds contain biotin.
Zinc
Zinc is vital for protein synthesis and cell growth, including nail cell regeneration. A lack of zinc can cause brittle, discolored nails that grow slowly. It can also result in horizontal grooves called Beau's lines.
Protein
Since nails are made of keratin protein, insufficient protein intake directly impacts nail strength. This can lead to weak and peeling nails.
The Impact of Other Key Nutrients
- Vitamin B12: Important for red blood cells and iron absorption; deficiency can cause discolored, weak nails.
- Magnesium: Involved in protein synthesis; deficiency can result in soft, flaky nails.
- Calcium: Severe lack linked to soft nails (hapalonychia) and longitudinal ridges.
Beyond Diet: Other Factors That Cause Brittle Nails
Aside from nutrition, other factors contribute to nail brittleness.
- External Factors: Frequent handwashing and exposure to harsh chemicals or acetone removers can dry out and weaken nails.
- Aging: Nails naturally become more brittle and grow slower with age.
- Medical Conditions: Hypothyroidism, Raynaud's syndrome, nail fungus, and psoriasis can cause brittle nails.
Comparison of Key Deficiencies and Nail Symptoms
| Deficiency | Primary Symptom(s) | Other Associated Signs |
|---|---|---|
| Iron | Koilonychia (spoon nails), thinness, pale nail beds | Fatigue, weakness, shortness of breath, pale skin |
| Biotin (B7) | Brittle, splitting, or thin fingernails | Red scaly rash, thinning hair |
| Zinc | Brittle nails, Beau's lines (horizontal grooves), white spots | Hair loss, slow wound healing, decreased appetite |
| Protein | Weak, peeling nails, slowed growth | Muscle wasting, fatigue |
How to Strengthen Brittle Nails
To improve nail strength:
- Optimize Your Diet: Eat foods rich in protein, iron, biotin, and zinc.
- Protect Your Hands: Wear gloves for wet work or chemical exposure.
- Moisturize Regularly: Use hand cream or cuticle oil.
- Avoid Harsh Products: Choose acetone-free removers and limit gels/acrylics.
- File Gently: File in one direction.
- Stay Hydrated: Drink enough water.
For more information on nutrients, refer to the NIH Office of Dietary Supplements.
Conclusion
Brittle nails can stem from various causes. While external factors play a role, nutritional deficiencies, particularly in iron, biotin, and zinc, are common culprits. Deficiencies in other nutrients and medical conditions also contribute. Improving nail health often requires a balanced diet and good nail care habits. Consulting a healthcare provider is recommended for diagnosis and treatment, especially if symptoms persist.
