Your eyes may be the window to your soul—but your nails can be the window to your health, says Andrea Cambio, M.D., a board-certified dermatologist in Cape Coral, FL. If yours could talk, they'd tell you to head to a dermatologist if you see any of these symptoms:
White or yellow spots
What it might be: A fungal infection. If left untreated, nails can thicken and crumble around the edges. Doctor-prescribed topical ointments and oral meds work best.
Brittleness or splitting
What it might be: Usually a sign of daily wear and tear (frequent hand washing, harsh cleaning products, polish remover, etc.). But sometimes brittle nails can signal a thyroid condition, especially if you're feeling weak and fatigued.
What it might be: A bacterial infection; often there's pain and swelling, too. Oral antibiotics should clear it up.
A dark spot or vertical brown stripes
What it might be: A benign mole or freckle under the nail, or possibly melanoma (skin cancer). See a dermatologist ASAP.
Horizontal ridges or depressions
What it might be: A symptom of a nutritional deficiency (usually iron) or the result of trauma—physical or emotional. Your doctor will need your medical history to determine the best treatment plan.