If you want some clues about your overall health, look down at your fingernails.
“Your nails are a very good reflection of your health. Many things can occur in the nails that can signify systemic or skin problems,” says dermatologist Christine Poblete-Lopez, MD.
Pay attention to anything on or around your fingernails or toenails that suddenly appears different, she says. “Anything that doesn’t look normal ought to be addressed. Your best course of action is to see a doctor as soon as possible.”
Here are six conditions that can also cause symptoms in the nails. However, for a diagnosis, it’s important to see your doctor, who will take many factors into account besides nail symptoms.
1. Stress
Fingernails and toenails are closely related to hair, Dr. Poblete-Lopez says. Just as your hair might fall out after an illness or a prolonged period of stress, your nails can also exhibit symptoms. Most frequently, stress will cause side-to-side lines to appear on your nails.
2. Moles or melanoma
A concern about nail color is one of the most common complaints dermatologists hear, Dr. Poblete-Lopez says. Discolorations usually appear in lines that run from cuticle to tip, and they can be benign moles or cancerous melanomas. African-Americans and Asians are more likely to experience normal pigmentation changes that are related to ethnicity.
You should consult a dermatologist if the skin under the nail plate – the hard part of the nail, covering the fingertips – develops any brown coloring, she says. These developments are always more of a concern if they affect a single finger instead of all. Brown lines that run into the cuticle could be a sign of melanoma. Ones that stop at or before the cuticle are likely caused by moles.
3. Arthritis
Small cysts that grow near or on the cuticles may arise with arthritis. These are benign and best addressed by a hand surgeon.
4. Kidney disease
Several nail changes can indicate the presence of acute or chronic kidney disease, Dr. Poblete-Lopez says:
Beau’s lines: These side-to-side lines can be a symptom of acute kidney disease.
Ridged nails: Also called koilonychia, rough nails with ridges can exist in the presence of kidney disease. These nails are also frequently spoon-shaped and concave, and they can point to iron-deficiency anemia.
White streaks/spots: Similar to psoriasis cases, distinct white streaks and spots on nails can point to chronic kidney disease.
5. Darier disease
Darier disease is a rare genetic disorder that appears mostly in adolescence. It shows up in the fingernails and toenails as broad, white or reddish stripes that run from cuticle to tip. A V-shaped nick near the fingertip can also indicate this condition, Dr. Poblete-Lopez says.