10 Nail Changes That May Indicate an Underlying Health Issue

4. White Spots and Lines - Nutritional Deficiencies and Systemic Disease

White spots, lines, and patches on nails, collectively known as leukonychia, can manifest in various patterns that provide important clues about nutritional status, systemic diseases, and metabolic disturbances affecting nail growth and development. Punctate leukonychia, appearing as small white spots scattered across the nail plate, is often attributed to minor trauma or zinc deficiency, though it can also indicate protein malnutrition or certain medications. More concerning are transverse white lines known as Mees' lines, which appear as horizontal bands across multiple nails and typically indicate severe systemic illness, heavy metal poisoning (particularly arsenic), or chemotherapy treatment. These lines form when nail matrix function is temporarily disrupted by severe physiological stress, creating areas of altered nail composition that appear white as they grow out. Muehrcke's lines present as paired horizontal white lines that disappear with pressure and are characteristically associated with hypoalbuminemia, often seen in liver disease, kidney disease, or severe malnutrition. Terry's nails, where the entire nail appears white except for a small pink or red band at the tip, can indicate liver cirrhosis, congestive heart failure, or diabetes mellitus. The timing and pattern of these white changes can help healthcare providers determine when the underlying condition occurred and monitor treatment response, as healthy nail growth gradually replaces the affected areas over several months.