Have you ever noticed white lines on your toenails? As with white spots on toenails after polish, this condition, known as leukonychia, can be a bit alarming when you first spot it. After all, our nails can tell us a lot about our overall health, and changes in their appearance often signal an underlying issue that needs attention.
That’s why it’s important to keep an eye on your nail health and consult with a healthcare professional about any unusual changes you may notice. The white lines in pictures of white lines on toenails can be caused by a number of different things, and it’s important to determine what’s behind the symptom.
This article provides a comprehensive overview of white lines on toenails, including what causes them and when it’s time to seek medical attention. We’ll explore the anatomy of the nail, discuss the different types of leukonychia (both true and apparent), and look at other conditions that might present with similar white lines. By the end of this article, you’ll have a better understanding of what those white lines might mean and how to address them.
Basic Nail Anatomy
To understand what those white lines could mean, let’s do a quick anatomy lesson. Your toenail isn’t just one solid piece; it’s a whole system working together.
- Nail plate: This is the hard, visible part of the nail that you paint with polish. It’s made of keratin, the same protein that makes up your hair.
- Nail bed: This is the skin underneath the nail plate. It provides support and helps the nail stay attached.
- Nail matrix: This is where the magic happens! Located under the cuticle, the matrix is responsible for nail growth. Cells in the matrix divide and create new nail cells.
- Lunula: That little half-moon shape at the base of your nail? That’s the lunula, and it’s part of the matrix.
- Nail folds: The skin that surrounds and protects the nail plate on three sides.
Toenails grow much slower than fingernails, only about 1 mm per month. So, any changes you see will take a while to grow out. Keep that in mind as you watch your white lines to see if they disappear.
Nail Examination Essentials
It’s important to examine your toenails regularly. Changes in your nails can be an indication of systemic disease. That’s why podiatrists will often look at your nails during routine exams.
Here’s how to properly examine your toenails:
- Remove any nail polish from your toenails.
- Find a well-lit area. Use a magnifying glass, if needed.
- Look at the color, shape, thickness, and texture of each nail.
- Note any abnormalities, such as white lines, ridges, or pits.
If you notice anything unusual, it’s best to show your doctor.
What do white lines on toenails mean? Leukonychia striata
Leukonychia (loo-koh-NIK-ee-uh) is the term for white lines or spots on the nails. It’s a common condition, and there are two main types.
True Leukonychia
With true leukonychia, the whiteness originates in the nail matrix (the area where the nail begins to grow) and moves up the nail as it grows. It happens when there’s a defect in the way the nail matrix forms keratin (the protein that makes up your nails).
Causes of true leukonychia include:
- Trauma to the nail matrix. This can happen from stubbing your toe or wearing shoes that are too tight.
- Systemic diseases. These are rarely the cause when the white lines are in horizontal stripes.
- Inherited conditions, such as Hailey-Hailey disease and Darier disease.
- Medications. This is also rare.
Apparent Leukonychia
With apparent leukonychia, the whiteness is in the nail bed (the skin under your nail) and doesn’t move as the nail grows. If you press on the nail, the white discoloration disappears briefly.
Causes of apparent leukonychia include:
- Muehrcke lines. These are transverse (horizontal) white lines that are associated with hypoalbuminemia (low levels of albumin, a protein, in the blood). These usually appear in pairs and disappear when you press on the nail.
- Half-and-half nails (Lindsay’s nails). With this condition, the half of the nail closest to the cuticle is white, and the half farthest from the cuticle is red or brown. This is often associated with chronic kidney disease.
- Terry’s nails. In this case, most of the nail is white, except for a narrow band of pink or brown at the very tip. This is associated with liver disease, heart failure, and diabetes.
How to Tell the Difference
The easiest way to tell the difference between true and apparent leukonychia is to watch the nail as it grows. True leukonychia will move up the nail as it grows, while apparent leukonychia will stay in the same place. Also, apparent leukonychia may disappear briefly if you press on the nail.
Other causes of white lines and spots on toenails
While injury is often the first thing that comes to mind, white marks on your toenails can have a variety of causes. Here are some other possibilities:
Onychomycosis (Fungal Nail Infection)
Did you know that fungal nail infections can cause white marks? Superficial white onychomycosis, in particular, shows up as white spots or streaks right on the surface of the nail. Onychomycosis is common, accounting for up to half of all nail diseases, and proximal subungual onychomycosis may present a serious threat in some cases.
Your doctor can diagnose a fungal infection by examining nail clippings under a microscope using a potassium hydroxide (KOH) stain or by sending the clippings off for a fungal culture.
Trauma
I know I said trauma wasn’t the only cause, but it’s still a common one! Even minor injuries can lead to small white spots (called punctate leukonychia), which will eventually grow out as your nail grows.
Medications
Certain medications can mess with your nails and cause white lines or spots to appear. Chemotherapy drugs are a common culprit, so if you’re undergoing chemo and notice nail changes, be sure to talk to your doctor.
Nutritional Deficiencies (less common, but possible)
Though less common than the other causes on this list, a lack of certain nutrients could be to blame. Zinc deficiency, for example, has been linked to nail abnormalities in some cases. Talk to your doctor about getting your nutrient levels checked, especially if you have a history of malabsorption or dietary restrictions.
Longitudinal melanonychia: Vertical brown-black nail lines
Okay, now let’s talk about something a little scarier: dark vertical lines on your toenails. This condition is called longitudinal melanonychia, and it means you have a brown or black line running from the base of your nail all the way to the tip.
What causes this? A few things, really. Sometimes it’s just trauma, an infection, or even a medication you’re taking. Endocrine disorders can also cause it. In some cases, it can be caused by a mole in your nail matrix. But, rarely, it can be a sign of subungual melanoma, which is a type of skin cancer.
Here’s when you need to worry and see a doctor immediately:
- Hutchinson’s sign: This is when the pigmentation extends beyond the nail and onto the skin around it.
- Rapid change: If the line changes quickly in appearance, get it checked out.
- Bandwidth: A band that’s wider than 6 mm should be evaluated.
- Blurred borders: If the edges of the line aren’t sharp and well-defined, see a doctor.
- No improvement: If you’ve had trauma to the nail or other abnormalities and the line isn’t improving with treatment, get it checked.
- Personal or family history: If you or your family have a history of melanoma, you should be extra cautious.
Basically, if you see a dark line on your toenail and anything about it seems off, get it checked by a professional. It’s always better to be safe than sorry when it comes to melanoma. Don’t panic, but don’t ignore it either.
Longitudinal erythronychia: vertical red nail lines
Okay, so we’ve talked about white lines. Now let’s talk about red ones. If you see red vertical lines on your toenails (or fingernails), you may have a condition called longitudinal erythronychia. Here’s what you need to know:
- What it looks like: You’ll notice red lines running from the cuticle to the tip of your nail. You might have one nail affected, or several. The red bands are usually about 3 mm wide.
- What causes it: If it’s just one nail, it could be a glomus tumor (a non-cancerous growth under the nail), trauma, or even a wart. If it’s multiple nails, it could be lichen planus or Darier disease.
- What to do about it: If the red line(s) are stable and you have no other symptoms, you can monitor it with photos and measurements. But if you notice any changes, you should see a doctor for a biopsy to rule out anything serious.
Beau lines
Beau lines are horizontal grooves that run across your nails, like tiny little ditches. They’re a sign that your nail growth was temporarily interrupted.
What causes them?
- Stress
- Systemic illness
- Certain medications
Because nails grow at a predictable rate, doctors can sometimes use Beau lines to estimate when the event that caused them occurred. Pretty neat, huh?
Frequently Asked Questions
What vitamin deficiency causes white lines on nails?
While not always the cause, white lines on nails (leukonychia) can sometimes be linked to deficiencies in zinc or calcium. However, it’s more often due to minor injuries to the nail matrix (the area where your nail grows from). A proper diagnosis requires a consultation with a healthcare professional.
What do kidney disease nails look like?
Kidney disease can manifest in several nail changes. One common sign is “half-and-half” nails (also called Lindsay’s nails), where the lower portion of the nail is white and the upper portion is brown or pink. Other possible signs include pale nails and horizontal lines (Beau’s lines).
What do liver disease nails look like?
Liver disease can sometimes cause Terry’s nails, where most of the nail appears white or pale, with a narrow band of pink or brown at the tip. Yellowing of the nails (jaundice) can also occur in severe liver conditions.
What do diabetic toenails look like?
Diabetes can lead to poor circulation and nerve damage, which can affect toenail health, and may even exacerbate issues such as autoimmune disease and toenail fungus. Diabetic toenails are more prone to fungal infections (onychomycosis), which can cause thickening, discoloration, and brittleness. It’s crucial for individuals with diabetes to maintain good foot hygiene and seek prompt treatment for any nail issues.
Why is there a streak on my toenail?
A dark streak on your toenail (melanonychia) can have several causes, ranging from harmless to concerning. It can be caused by injury, fungal infection, medication side effects, or, in rare cases, melanoma (a type of skin cancer). If you notice a new, dark streak on your toenail, especially if it’s widening, blurring, or associated with changes in the surrounding skin, it’s essential to get it evaluated by a dermatologist or podiatrist to rule out any serious conditions.
Closing Thoughts
White lines on your toenails can be caused by a number of things. Sometimes, they’re due to a minor injury, but they can also be a symptom of a health condition.
When you find something unusual on your nails, it’s important to check it out closely. If you have other symptoms or risk factors along with the white lines, it’s a good idea to see a doctor. They can help you figure out what’s causing the changes in your nails and recommend the best course of action.