6 Things Your Nails Say About Your Health

“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 (not cancerous) and best addressed by a hand surgeon.

4. Psoriasis

This common skin condition is usually characterized by scaly, red patches, but it can also impact fingernails and toenails, Dr. Poblete-Lopez says.

If you have yellow-red discoloring on your nail, often called an “oil drop” or “salmon patch,” you should consult your dermatologist. Here are other symptoms that can also indicate psoriasis:

Indentations: Nicks or pits on the nail plate, which is the hard part of the nail that covers the fingertips.

Beau’s lines: Lines that run side-to-side across the nail.

Skin thickening/nail loosening: Thickening of skin under the nail, which can dislodge the nail (onycholysis) from the nail bed. This generally starts at the tip and works their way toward the cuticle.

White areas: Distinct white spots on the nails, also called leukonychia. (The cloudy white spots that sometimes appear on fingernails and toenails do not fall into the category, and aren’t cause for concern, according to Dr. Poblete-Lopez.)

Black lines: Black lines running from tip to cuticle could be tiny clots called splinter hemorrhages or dilated and burst capillaries — potential symptoms of psoriasis.

Redness: The usually pale areas near the cuticle turn red, which could be caused by congested capillaries, another possible sign of psoriasis.

RELATED: How to Deal If Your Psoriasis Leads to Psoriatic Arthritis

5. 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.

6. Darier disease

Darier disease is a rare genetic disorder that causes a skin rash and 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.

Prevention

Preventing underlying conditions that impact your nails isn’t always possible, Dr. Poblete-Lopez says, but you can care for your nails by staying hydrated and eating a well-balanced diet. Be sure you’re consuming enough Vitamin B and zinc because those nutrients greatly strengthen your nails.

In many cases, she says, changes to your nails can be normal and don’t point to any undiagnosed health changes. But, if you have a question, consulting your doctor is always best.

“Some nails may not appear smooth or they might have longitudinal strips or ridges. As long as whatever you see is consistent throughout the distribution of the nail, it’s likely OK,” she says. “If there’s something out of the ordinary, though, it’s reasonable to see a dermatologist.”