Vertical stripes, or longitudinal striations, are common with aging, but if they appear suddenly or become more pronounced, they may point to nutritional deficiencies, such as lack of vitamin B12, iron, or magnesium. They could also signal conditions like anemia or thyroid imbalances.
Horizontal stripes, known as Beau’s lines, are often caused by trauma or illness that disrupts nail growth. Conditions like malnutrition, diabetes, respiratory diseases, or heart attacks can cause these grooves. If Beau’s lines appear on all nails, it may indicate a systemic disease, making a doctor’s visit essential.
